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published/20180710 Building a Messenger App- Messages.md
Normal file
315
published/20180710 Building a Messenger App- Messages.md
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@ -0,0 +1,315 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (gxlct008)
|
||||
[#]: reviewer: (wxy)
|
||||
[#]: publisher: (wxy)
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||||
[#]: url: (https://linux.cn/article-12680-1.html)
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[#]: subject: (Building a Messenger App: Messages)
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[#]: via: (https://nicolasparada.netlify.com/posts/go-messenger-messages/)
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[#]: author: (Nicolás Parada https://nicolasparada.netlify.com/)
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构建一个即时消息应用（四）：消息
|
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======
|
||||
|
||||
|
||||
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本文是该系列的第四篇。
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* [第一篇: 模式][1]
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* [第二篇: OAuth][2]
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* [第三篇: 对话][3]
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在这篇文章中，我们将对端点进行编码，以创建一条消息并列出它们，同时还将编写一个端点以更新参与者上次阅读消息的时间。 首先在 `main()` 函数中添加这些路由。
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```
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router.HandleFunc("POST", "/api/conversations/:conversationID/messages", requireJSON(guard(createMessage)))
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router.HandleFunc("GET", "/api/conversations/:conversationID/messages", guard(getMessages))
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router.HandleFunc("POST", "/api/conversations/:conversationID/read_messages", guard(readMessages))
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```
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消息会进入对话，因此端点包含对话 ID。
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### 创建消息
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该端点处理对 `/api/conversations/{conversationID}/messages` 的 POST 请求，其 JSON 主体仅包含消息内容，并返回新创建的消息。它有两个副作用：更新对话 `last_message_id` 以及更新参与者 `messages_read_at`。
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```
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func createMessage(w http.ResponseWriter, r *http.Request) {
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var input struct {
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Content string `json:"content"`
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}
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defer r.Body.Close()
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if err := json.NewDecoder(r.Body).Decode(&input); err != nil {
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http.Error(w, err.Error(), http.StatusBadRequest)
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return
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}
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errs := make(map[string]string)
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input.Content = removeSpaces(input.Content)
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if input.Content == "" {
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errs["content"] = "Message content required"
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} else if len([]rune(input.Content)) > 480 {
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errs["content"] = "Message too long. 480 max"
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}
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if len(errs) != 0 {
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respond(w, Errors{errs}, http.StatusUnprocessableEntity)
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return
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}
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ctx := r.Context()
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authUserID := ctx.Value(keyAuthUserID).(string)
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conversationID := way.Param(ctx, "conversationID")
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tx, err := db.BeginTx(ctx, nil)
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if err != nil {
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respondError(w, fmt.Errorf("could not begin tx: %v", err))
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return
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}
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defer tx.Rollback()
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isParticipant, err := queryParticipantExistance(ctx, tx, authUserID, conversationID)
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if err != nil {
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respondError(w, fmt.Errorf("could not query participant existance: %v", err))
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return
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}
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if !isParticipant {
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http.Error(w, "Conversation not found", http.StatusNotFound)
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return
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}
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var message Message
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if err := tx.QueryRowContext(ctx, `
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INSERT INTO messages (content, user_id, conversation_id) VALUES
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($1, $2, $3)
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RETURNING id, created_at
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`, input.Content, authUserID, conversationID).Scan(
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&message.ID,
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&message.CreatedAt,
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); err != nil {
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respondError(w, fmt.Errorf("could not insert message: %v", err))
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return
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}
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if _, err := tx.ExecContext(ctx, `
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UPDATE conversations SET last_message_id = $1
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WHERE id = $2
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`, message.ID, conversationID); err != nil {
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respondError(w, fmt.Errorf("could not update conversation last message ID: %v", err))
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return
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}
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if err = tx.Commit(); err != nil {
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respondError(w, fmt.Errorf("could not commit tx to create a message: %v", err))
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return
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}
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go func() {
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if err = updateMessagesReadAt(nil, authUserID, conversationID); err != nil {
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log.Printf("could not update messages read at: %v\n", err)
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}
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}()
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message.Content = input.Content
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message.UserID = authUserID
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message.ConversationID = conversationID
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// TODO: notify about new message.
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message.Mine = true
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respond(w, message, http.StatusCreated)
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}
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```
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首先，它将请求正文解码为包含消息内容的结构。然后，它验证内容不为空并且少于 480 个字符。
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```
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var rxSpaces = regexp.MustCompile("\\s+")
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func removeSpaces(s string) string {
|
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if s == "" {
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return s
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}
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|
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lines := make([]string, 0)
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for _, line := range strings.Split(s, "\n") {
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line = rxSpaces.ReplaceAllLiteralString(line, " ")
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line = strings.TrimSpace(line)
|
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if line != "" {
|
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lines = append(lines, line)
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}
|
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}
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return strings.Join(lines, "\n")
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}
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```
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这是删除空格的函数。它遍历每一行，删除两个以上的连续空格，然后回非空行。
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验证之后，它将启动一个 SQL 事务。首先，它查询对话中的参与者是否存在。
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```
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func queryParticipantExistance(ctx context.Context, tx *sql.Tx, userID, conversationID string) (bool, error) {
|
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if ctx == nil {
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ctx = context.Background()
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}
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var exists bool
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if err := tx.QueryRowContext(ctx, `SELECT EXISTS (
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SELECT 1 FROM participants
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WHERE user_id = $1 AND conversation_id = $2
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)`, userID, conversationID).Scan(&exists); err != nil {
|
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return false, err
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}
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return exists, nil
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}
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```
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我将其提取到一个函数中，因为稍后可以重用。
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如果用户不是对话参与者，我们将返回一个 `404 NOT Found` 错误。
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然后，它插入消息并更新对话 `last_message_id`。从这时起，由于我们不允许删除消息，因此 `last_message_id` 不能为 `NULL`。
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接下来提交事务，并在 goroutine 中更新参与者 `messages_read_at`。
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```
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func updateMessagesReadAt(ctx context.Context, userID, conversationID string) error {
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if ctx == nil {
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ctx = context.Background()
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}
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if _, err := db.ExecContext(ctx, `
|
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UPDATE participants SET messages_read_at = now()
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WHERE user_id = $1 AND conversation_id = $2
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`, userID, conversationID); err != nil {
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return err
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}
|
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return nil
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}
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```
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|
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在回复这条新消息之前，我们必须通知一下。这是我们将要在下一篇文章中编写的实时部分，因此我在那里留一了个注释。
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### 获取消息
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这个端点处理对 `/api/conversations/{conversationID}/messages` 的 GET 请求。 它用一个包含会话中所有消息的 JSON 数组进行响应。它还具有更新参与者 `messages_read_at` 的副作用。
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|
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```
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func getMessages(w http.ResponseWriter, r *http.Request) {
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ctx := r.Context()
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authUserID := ctx.Value(keyAuthUserID).(string)
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conversationID := way.Param(ctx, "conversationID")
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tx, err := db.BeginTx(ctx, &sql.TxOptions{ReadOnly: true})
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if err != nil {
|
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respondError(w, fmt.Errorf("could not begin tx: %v", err))
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return
|
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}
|
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defer tx.Rollback()
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|
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isParticipant, err := queryParticipantExistance(ctx, tx, authUserID, conversationID)
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if err != nil {
|
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respondError(w, fmt.Errorf("could not query participant existance: %v", err))
|
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return
|
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}
|
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|
||||
if !isParticipant {
|
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http.Error(w, "Conversation not found", http.StatusNotFound)
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return
|
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}
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|
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rows, err := tx.QueryContext(ctx, `
|
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SELECT
|
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id,
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content,
|
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created_at,
|
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user_id = $1 AS mine
|
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FROM messages
|
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WHERE messages.conversation_id = $2
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ORDER BY messages.created_at DESC
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`, authUserID, conversationID)
|
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if err != nil {
|
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respondError(w, fmt.Errorf("could not query messages: %v", err))
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return
|
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}
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defer rows.Close()
|
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|
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messages := make([]Message, 0)
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for rows.Next() {
|
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var message Message
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if err = rows.Scan(
|
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&message.ID,
|
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&message.Content,
|
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&message.CreatedAt,
|
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&message.Mine,
|
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); err != nil {
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respondError(w, fmt.Errorf("could not scan message: %v", err))
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||||
return
|
||||
}
|
||||
|
||||
messages = append(messages, message)
|
||||
}
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|
||||
if err = rows.Err(); err != nil {
|
||||
respondError(w, fmt.Errorf("could not iterate over messages: %v", err))
|
||||
return
|
||||
}
|
||||
|
||||
if err = tx.Commit(); err != nil {
|
||||
respondError(w, fmt.Errorf("could not commit tx to get messages: %v", err))
|
||||
return
|
||||
}
|
||||
|
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go func() {
|
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if err = updateMessagesReadAt(nil, authUserID, conversationID); err != nil {
|
||||
log.Printf("could not update messages read at: %v\n", err)
|
||||
}
|
||||
}()
|
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|
||||
respond(w, messages, http.StatusOK)
|
||||
}
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```
|
||||
|
||||
首先，它以只读模式开始一个 SQL 事务。检查参与者是否存在，并查询所有消息。在每条消息中，我们使用当前经过身份验证的用户 ID 来了解用户是否拥有该消息（`mine`）。 然后，它提交事务，在 goroutine 中更新参与者 `messages_read_at` 并以消息响应。
|
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|
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### 读取消息
|
||||
|
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该端点处理对 `/api/conversations/{conversationID}/read_messages` 的 POST 请求。 没有任何请求或响应主体。 在前端，每次有新消息到达实时流时，我们都会发出此请求。
|
||||
|
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```
|
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func readMessages(w http.ResponseWriter, r *http.Request) {
|
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ctx := r.Context()
|
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authUserID := ctx.Value(keyAuthUserID).(string)
|
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conversationID := way.Param(ctx, "conversationID")
|
||||
|
||||
if err := updateMessagesReadAt(ctx, authUserID, conversationID); err != nil {
|
||||
respondError(w, fmt.Errorf("could not update messages read at: %v", err))
|
||||
return
|
||||
}
|
||||
|
||||
w.WriteHeader(http.StatusNoContent)
|
||||
}
|
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```
|
||||
|
||||
它使用了与更新参与者 `messages_read_at` 相同的函数。
|
||||
|
||||
* * *
|
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|
||||
到此为止。实时消息是后台仅剩的部分了。请等待下一篇文章。
|
||||
|
||||
- [源代码][4]
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://nicolasparada.netlify.com/posts/go-messenger-messages/
|
||||
|
||||
作者：[Nicolás Parada][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[gxlct008](https://github.com/gxlct008)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://nicolasparada.netlify.com/
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://linux.cn/article-11396-1.html
|
||||
[2]: https://linux.cn/article-11510-1.html
|
||||
[3]: https://linux.cn/article-12056-1.html
|
||||
[4]: https://github.com/nicolasparada/go-messenger-demo
|
||||
@ -0,0 +1,175 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (gxlct008)
|
||||
[#]: reviewer: (wxy)
|
||||
[#]: publisher: (wxy)
|
||||
[#]: url: (https://linux.cn/article-12685-1.html)
|
||||
[#]: subject: (Building a Messenger App: Realtime Messages)
|
||||
[#]: via: (https://nicolasparada.netlify.com/posts/go-messenger-realtime-messages/)
|
||||
[#]: author: (Nicolás Parada https://nicolasparada.netlify.com/)
|
||||
|
||||
构建一个即时消息应用（五）：实时消息
|
||||
======
|
||||
|
||||
|
||||
|
||||
本文是该系列的第五篇。
|
||||
|
||||
* [第一篇: 模式][1]
|
||||
* [第二篇: OAuth][2]
|
||||
* [第三篇: 对话][3]
|
||||
* [第四篇: 消息][4]
|
||||
|
||||
对于实时消息，我们将使用 <ruby>[服务器发送事件][5]<rt>Server-Sent Events</rt></ruby>。这是一个打开的连接，我们可以在其中传输数据流。我们会有个端点，用户会在其中订阅发送给他的所有消息。
|
||||
|
||||
### 消息户端
|
||||
|
||||
在 HTTP 部分之前，让我们先编写一个<ruby>映射<rt>map</rt></ruby> ，让所有客户端都监听消息。 像这样全局初始化：
|
||||
|
||||
```go
|
||||
type MessageClient struct {
|
||||
Messages chan Message
|
||||
UserID string
|
||||
}
|
||||
|
||||
var messageClients sync.Map
|
||||
```
|
||||
|
||||
### 已创建的新消息
|
||||
|
||||
还记得在 [上一篇文章][4] 中，当我们创建这条消息时，我们留下了一个 “TODO” 注释。在那里，我们将使用这个函数来调度一个 goroutine。
|
||||
|
||||
```go
|
||||
go messageCreated(message)
|
||||
```
|
||||
|
||||
把这行代码插入到我们留注释的位置。
|
||||
|
||||
```go
|
||||
func messageCreated(message Message) error {
|
||||
if err := db.QueryRow(`
|
||||
SELECT user_id FROM participants
|
||||
WHERE user_id != $1 and conversation_id = $2
|
||||
`, message.UserID, message.ConversationID).
|
||||
Scan(&message.ReceiverID); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
go broadcastMessage(message)
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
func broadcastMessage(message Message) {
|
||||
messageClients.Range(func(key, _ interface{}) bool {
|
||||
client := key.(*MessageClient)
|
||||
if client.UserID == message.ReceiverID {
|
||||
client.Messages <- message
|
||||
}
|
||||
return true
|
||||
})
|
||||
}
|
||||
```
|
||||
|
||||
该函数查询接收者 ID（其他参与者 ID），并将消息发送给所有客户端。
|
||||
|
||||
### 订阅消息
|
||||
|
||||
让我们转到 `main()` 函数并添加以下路由：
|
||||
|
||||
```go
|
||||
router.HandleFunc("GET", "/api/messages", guard(subscribeToMessages))
|
||||
```
|
||||
|
||||
此端点处理 `/api/messages` 上的 GET 请求。请求应该是一个 [EventSource][6] 连接。它用一个事件流响应，其中的数据是 JSON 格式的。
|
||||
|
||||
```go
|
||||
func subscribeToMessages(w http.ResponseWriter, r *http.Request) {
|
||||
if a := r.Header.Get("Accept"); !strings.Contains(a, "text/event-stream") {
|
||||
http.Error(w, "This endpoint requires an EventSource connection", http.StatusNotAcceptable)
|
||||
return
|
||||
}
|
||||
|
||||
f, ok := w.(http.Flusher)
|
||||
if !ok {
|
||||
respondError(w, errors.New("streaming unsupported"))
|
||||
return
|
||||
}
|
||||
|
||||
ctx := r.Context()
|
||||
authUserID := ctx.Value(keyAuthUserID).(string)
|
||||
|
||||
h := w.Header()
|
||||
h.Set("Cache-Control", "no-cache")
|
||||
h.Set("Connection", "keep-alive")
|
||||
h.Set("Content-Type", "text/event-stream")
|
||||
|
||||
messages := make(chan Message)
|
||||
defer close(messages)
|
||||
|
||||
client := &MessageClient{Messages: messages, UserID: authUserID}
|
||||
messageClients.Store(client, nil)
|
||||
defer messageClients.Delete(client)
|
||||
|
||||
for {
|
||||
select {
|
||||
case <-ctx.Done():
|
||||
return
|
||||
case message := <-messages:
|
||||
if b, err := json.Marshal(message); err != nil {
|
||||
log.Printf("could not marshall message: %v\n", err)
|
||||
fmt.Fprintf(w, "event: error\ndata: %v\n\n", err)
|
||||
} else {
|
||||
fmt.Fprintf(w, "data: %s\n\n", b)
|
||||
}
|
||||
f.Flush()
|
||||
}
|
||||
}
|
||||
}
|
||||
```
|
||||
|
||||
首先，它检查请求头是否正确，并检查服务器是否支持流式传输。我们创建一个消息通道，用它来构建一个客户端，并将其存储在客户端映射中。每当创建新消息时，它都会进入这个通道，因此我们可以通过 `for-select` 循环从中读取。
|
||||
|
||||
<ruby>服务器发送事件<rt>Server-Sent Events</rt></ruby>使用以下格式发送数据：
|
||||
|
||||
```go
|
||||
data: some data here\n\n
|
||||
```
|
||||
|
||||
我们以 JSON 格式发送：
|
||||
|
||||
```json
|
||||
data: {"foo":"bar"}\n\n
|
||||
```
|
||||
|
||||
我们使用 `fmt.Fprintf()` 以这种格式写入响应<ruby>写入器<rt>writter</rt></ruby>，并在循环的每次迭代中刷新数据。
|
||||
|
||||
这个循环会一直运行，直到使用请求上下文关闭连接为止。我们延迟了通道的关闭和客户端的删除，因此，当循环结束时，通道将被关闭，客户端不会收到更多的消息。
|
||||
|
||||
注意，<ruby>服务器发送事件<rt>Server-Sent Events</rt></ruby>（EventSource）的 JavaScript API 不支持设置自定义请求头😒，所以我们不能设置 `Authorization: Bearer <token>`。这就是为什么 `guard()` 中间件也会从 URL 查询字符串中读取令牌的原因。
|
||||
|
||||
* * *
|
||||
|
||||
实时消息部分到此结束。我想说的是，这就是后端的全部内容。但是为了编写前端代码，我将再增加一个登录端点：一个仅用于开发的登录。
|
||||
|
||||
- [源代码][7]
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://nicolasparada.netlify.com/posts/go-messenger-realtime-messages/
|
||||
|
||||
作者：[Nicolás Parada][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[gxlct008](https://github.com/gxlct008)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://nicolasparada.netlify.com/
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://linux.cn/article-11396-1.html
|
||||
[2]: https://linux.cn/article-11510-1.html
|
||||
[3]: https://linux.cn/article-12056-1.html
|
||||
[4]: https://linux.cn/article-12680-1.html
|
||||
[5]: https://developer.mozilla.org/en-US/docs/Web/API/Server-sent_events
|
||||
[6]: https://developer.mozilla.org/en-US/docs/Web/API/EventSource
|
||||
[7]: https://github.com/nicolasparada/go-messenger-demo
|
||||
@ -1,38 +1,38 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: translator: (gxlct008)
|
||||
[#]: reviewer: (wxy)
|
||||
[#]: publisher: (wxy)
|
||||
[#]: url: (https://linux.cn/article-12692-1.html)
|
||||
[#]: subject: (Building a Messenger App: Development Login)
|
||||
[#]: via: (https://nicolasparada.netlify.com/posts/go-messenger-dev-login/)
|
||||
[#]: author: (Nicolás Parada https://nicolasparada.netlify.com/)
|
||||
|
||||
Building a Messenger App: Development Login
|
||||
构建一个即时消息应用（六）：仅用于开发的登录
|
||||
======
|
||||
|
||||
This post is the 6th on a series:
|
||||
|
||||
|
||||
* [Part 1: Schema][1]
|
||||
* [Part 2: OAuth][2]
|
||||
* [Part 3: Conversations][3]
|
||||
* [Part 4: Messages][4]
|
||||
* [Part 5: Realtime Messages][5]
|
||||
本文是该系列的第六篇。
|
||||
|
||||
* [第一篇: 模式][1]
|
||||
* [第二篇: OAuth][2]
|
||||
* [第三篇: 对话][3]
|
||||
* [第四篇: 消息][4]
|
||||
* [第五篇: 实时消息][5]
|
||||
|
||||
我们已经实现了通过 GitHub 登录，但是如果想把玩一下这个 app，我们需要几个用户来测试它。在这篇文章中，我们将添加一个为任何用户提供登录的端点，只需提供用户名即可。该端点仅用于开发。
|
||||
|
||||
We already implemented login through GitHub, but if we want to play around with the app, we need a couple of users to test it. In this post we’ll add an endpoint to login as any user just giving an username. This endpoint will be just for development.
|
||||
首先在 `main()` 函数中添加此路由。
|
||||
|
||||
Start by adding this route in the `main()` function.
|
||||
|
||||
```
|
||||
```go
|
||||
router.HandleFunc("POST", "/api/login", requireJSON(login))
|
||||
```
|
||||
|
||||
### Login
|
||||
### 登录
|
||||
|
||||
This function handles POST requests to `/api/login` with a JSON body with just an username and returns the authenticated user, a token and expiration date of it in JSON format.
|
||||
此函数处理对 `/api/login` 的 POST 请求，其中 JSON body 只包含用户名，并以 JSON 格式返回通过认证的用户、令牌和过期日期。
|
||||
|
||||
```
|
||||
```go
|
||||
func login(w http.ResponseWriter, r *http.Request) {
|
||||
if origin.Hostname() != "localhost" {
|
||||
http.NotFound(w, r)
|
||||
@ -81,9 +81,9 @@ func login(w http.ResponseWriter, r *http.Request) {
|
||||
}
|
||||
```
|
||||
|
||||
First it checks we are on localhost or it responds with `404 Not Found`. It decodes the body skipping validation since this is just for development. Then it queries to the database for a user with the given username, if none is found, it returns with `404 Not Found`. Then it issues a new JSON web token using the user ID as Subject.
|
||||
首先，它检查我们是否在本地主机上，或者响应为 `404 Not Found`。它解码主体跳过验证，因为这只是为了开发。然后在数据库中查询给定用户名的用户，如果没有，则返回 `404 NOT Found`。然后，它使用用户 ID 作为主题发布一个新的 JSON Web 令牌。
|
||||
|
||||
```
|
||||
```go
|
||||
func issueToken(subject string, exp time.Time) (string, error) {
|
||||
token, err := jwtSigner.Encode(jwt.Claims{
|
||||
Subject: subject,
|
||||
@ -96,33 +96,33 @@ func issueToken(subject string, exp time.Time) (string, error) {
|
||||
}
|
||||
```
|
||||
|
||||
The function does the same we did [previously][2]. I just moved it to reuse code.
|
||||
该函数执行的操作与 [前文][2] 相同。我只是将其移过来以重用代码。
|
||||
|
||||
After creating the token, it responds with the user, token and expiration date.
|
||||
创建令牌后，它将使用用户、令牌和到期日期进行响应。
|
||||
|
||||
### Seed Users
|
||||
### 种子用户
|
||||
|
||||
Now you can add users to play with to the database.
|
||||
现在，你可以将要操作的用户添加到数据库中。
|
||||
|
||||
```
|
||||
```sql
|
||||
INSERT INTO users (id, username) VALUES
|
||||
(1, 'john'),
|
||||
(2, 'jane');
|
||||
```
|
||||
|
||||
You can save it to a file and pipe it to the Cockroach CLI.
|
||||
你可以将其保存到文件中，并通过管道将其传送到 Cockroach CLI。
|
||||
|
||||
```
|
||||
```bash
|
||||
cat seed_users.sql | cockroach sql --insecure -d messenger
|
||||
```
|
||||
|
||||
* * *
|
||||
|
||||
That’s it. Once you deploy the code to production and use your own domain this login function won’t be available.
|
||||
就是这样。一旦将代码部署到生产环境并使用自己的域后，该登录功能将不可用。
|
||||
|
||||
This post concludes the backend.
|
||||
本文也结束了所有的后端开发部分。
|
||||
|
||||
[Souce Code][6]
|
||||
- [源代码][6]
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
@ -130,16 +130,16 @@ via: https://nicolasparada.netlify.com/posts/go-messenger-dev-login/
|
||||
|
||||
作者：[Nicolás Parada][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
译者：[gxlct008](https://github.com/gxlct008)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://nicolasparada.netlify.com/
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://nicolasparada.netlify.com/posts/go-messenger-schema/
|
||||
[2]: https://nicolasparada.netlify.com/posts/go-messenger-oauth/
|
||||
[3]: https://nicolasparada.netlify.com/posts/go-messenger-conversations/
|
||||
[4]: https://nicolasparada.netlify.com/posts/go-messenger-messages/
|
||||
[5]: https://nicolasparada.netlify.com/posts/go-messenger-realtime-messages/
|
||||
[1]: https://linux.cn/article-11396-1.html
|
||||
[2]: https://linux.cn/article-11510-1.html
|
||||
[3]: https://linux.cn/article-12056-1.html
|
||||
[4]: https://linux.cn/article-12680-1.html
|
||||
[5]: https://linux.cn/article-12685-1.html
|
||||
[6]: https://github.com/nicolasparada/go-messenger-demo
|
||||
@ -1,8 +1,8 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (rakino)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: reviewer: (wxy)
|
||||
[#]: publisher: (wxy)
|
||||
[#]: url: (https://linux.cn/article-12689-1.html)
|
||||
[#]: subject: (How to Disable IPv6 on Ubuntu Linux)
|
||||
[#]: via: (https://itsfoss.com/disable-ipv6-ubuntu-linux/)
|
||||
[#]: author: (Sergiu https://itsfoss.com/author/sergiu/)
|
||||
@ -14,31 +14,33 @@
|
||||
|
||||
### 什么是 IPv6？为什么会想要禁用它？
|
||||
|
||||
<ruby>**[网际协议第6版][1]**<rt>Internet Protocol version 6</rt></ruby>[（][1] **[IPv6][1]**[）][1]是网际协议（IP）的最新版本。网际协议是一种通信协议，它为网络上的计算机提供识别和定位系统，并在互联网上进行通信路由。IPv6 是在 1998 年以取代 **IPv4** 协议为目的被设计出来的。
|
||||
<ruby>[互联网协议第 6 版][1]<rt>Internet Protocol version 6</rt></ruby>（IPv6）是互联网协议（IP）的最新版本。互联网协议是一种通信协议，它为网络上的计算机提供识别和定位系统，并在互联网上进行通信路由。IPv6 于 1998 年设计，以取代 IPv4 协议。
|
||||
|
||||
**IPv6** 意在提高安全性与性能的同时保证地址不被用尽；它可以在全球范围内为每台设备分配唯一的以 **128 位元**存储的地址，而 IPv4 只使用了 32 位元。
|
||||
**IPv6** 意在提高安全性与性能的同时保证地址不被用尽；它可以在全球范围内为每台设备分配唯一的以 **128 位比特**存储的地址，而 IPv4 只使用了 32 位比特。
|
||||
|
||||
![Disable IPv6 Ubuntu][2]
|
||||
|
||||
尽管 IPv6 的目标是取代 IPv4，但目前还有很长的路要走；互联网上只有少于 **30%** 的网站支持 IPv6（[这里][3] 是谷歌的统计），IPv6 有时也会导致 [一些程序出现问题][4]。
|
||||
尽管 IPv6 的目标是取代 IPv4，但目前还有很长的路要走；互联网上只有不到 **30%** 的网站支持 IPv6（[这里][3] 是谷歌的统计），IPv6 有时也给 [一些应用带来问题][4]。
|
||||
|
||||
由于 IPv6 使用全球（唯一分配的）路由地址，以及（仍然）有<ruby>互联网服务供应商<rt>Internet Service Provider</rt></ruby>（ISP）不提供 IPv6 支持的事实，IPv6 这一功能在提供全球服务的<ruby>**虚拟私人网络**<rt>Virtual Private Network</rt></ruby>（VPN）供应商的优先级列表中处于较低的位置，这样一来，他们就可以专注于对 VPN 用户最重要的事情：安全。
|
||||
|
||||
不想让自己暴露在各种威胁之下可能是另一个让你想在系统上禁用 IPv6 的原因。虽然 IPv6 本身比 IPv4 更安全，但我所指的风险是另一种性质上的。如果你不积极使用 IPv6 及其功能，[启用 IPv6 后，你会很容易受到各种攻击][5]，因而为黑客提供另一种可能的利用工具。
|
||||
不想让自己暴露在各种威胁之下可能是另一个让你想在系统上禁用 IPv6 的原因。虽然 IPv6 本身比 IPv4 更安全，但我所指的风险是另一种性质上的。如果你不实际使用 IPv6 及其功能，那么[启用 IPv6 后，你会很容易受到各种攻击][5]，因而为黑客提供另一种可能的利用工具。
|
||||
|
||||
同样，配置基本的网络规则是不够的；就像对 IPv4 一样，你需要密切关注 IPv6 的配置，这可能会是一件相当麻烦的事情（维护也是）。并且随着 IPv6 而来的将会是一套不同于 IPv4 的问题（鉴于这个协议的年龄，许多问题已经可以在网上找到了），这又会使你的系统多了一层复杂性。
|
||||
同样，只配置基本的网络规则是不够的；你必须像对 IPv4 一样，对调整 IPv6 的配置给予同样的关注，这可能会是一件相当麻烦的事情（维护也是）。并且随着 IPv6 而来的将会是一套不同于 IPv4 的问题（鉴于这个协议的年龄，许多问题已经可以在网上找到了），这又会使你的系统多了一层复杂性。
|
||||
|
||||
据观察，在某些情况下，禁用 IPv6 有助于提高 Ubuntu 的 WiFi 速度。
|
||||
|
||||
### 在 Ubuntu 上禁用 IPv6 [高级用户]
|
||||
|
||||
在本节中，我会详述如何在 Ubuntu 上禁用 IPv6 协议，请打开终端（**默认键：** CTRL+ALT+T），让我们开始吧！
|
||||
在本节中，我会详述如何在 Ubuntu 上禁用 IPv6 协议，请打开终端（默认快捷键：`CTRL+ALT+T`），让我们开始吧！
|
||||
|
||||
**注意：**_接下来大部分输入终端的命令都需要 root 权限（**sudo**）。_
|
||||
**注意：** 接下来大部分输入终端的命令都需要 root 权限（`sudo`）。
|
||||
|
||||
警告！
|
||||
> 警告！
|
||||
>
|
||||
> 如果你是一个普通 Linux 桌面用户，并且偏好稳定的工作系统，请避开本教程，接下来的部分是为那些知道自己在做什么以及为什么要这么做的用户准备的。
|
||||
|
||||
如果你是普通 Linux 桌面用户，并且偏好稳定的工作系统，请避开本教程，接下来的部分是为那些知道自己在做什么以及为什么要这么做的用户准备的。
|
||||
|
||||
#### 1\. 使用 Sysctl 禁用 IPv6
|
||||
#### 1、使用 sysctl 禁用 IPv6
|
||||
|
||||
首先，可以执行以下命令来**检查** IPv6 是否已经启用：
|
||||
|
||||
@ -50,7 +52,7 @@ ip a
|
||||
|
||||
![IPv6 Address Ubuntu][7]
|
||||
|
||||
在教程 [在 Ubuntu 中重启网络][8] 中，你已经见过 sysctl 命令了，在这里我们也同样会用到它。要**禁用 IPv6**，只需要输入三条命令：
|
||||
在教程《[在 Ubuntu 中重启网络][8]》（LCTT 译注：其实这篇文章并没有提到使用 sysctl 的方法……）中，你已经见过 `sysctl` 命令了，在这里我们也同样会用到它。要**禁用 IPv6**，只需要输入三条命令：
|
||||
|
||||
```
|
||||
sudo sysctl -w net.ipv6.conf.all.disable_ipv6=1
|
||||
@ -58,8 +60,6 @@ sudo sysctl -w net.ipv6.conf.default.disable_ipv6=1
|
||||
sudo sysctl -w net.ipv6.conf.lo.disable_ipv6=1
|
||||
```
|
||||
|
||||
（译注：这篇文章 LCTT 有翻译，在 [这里：《Linux 初学者：如何在 Ubuntu 中重启网络》][patch-1]；不过尴尬的是，并没有提到使用 sysctl 的方法……）
|
||||
|
||||
检查命令是否生效：
|
||||
|
||||
```
|
||||
@ -70,11 +70,11 @@ ip a
|
||||
|
||||
![IPv6 Disabled Ubuntu][9]
|
||||
|
||||
然而这种方法只能**临时禁用 IPv6**，因此在下次系统启动的时候， IPv6 仍然会被启用。
|
||||
然而这种方法只能**临时禁用 IPv6**，因此在下次系统启动的时候，IPv6 仍然会被启用。
|
||||
|
||||
（译注：这里的临时禁用是指这次所做的改变直到此次关机之前都有效，因为相关的参数是存储在内存中的，可以改变值，但是在内存断电后就会丢失；这种意义上来讲，下文所述的两种方法都是临时的，只不过改变参数值的时机是在系统启动的早期，并且每次系统启动时都有应用而已。那么如何完成这种意义上的永久改变？答案是在编译内核的时候禁用相关功能，然后要后悔就只能重新编译内核了（悲）。）
|
||||
（LCTT 译注：这里的临时禁用是指这次所做的改变直到此次关机之前都有效，因为相关的参数是存储在内存中的，可以改变值，但是在内存断电后就会丢失；这种意义上来讲，下文所述的两种方法都是临时的，只不过改变参数值的时机是在系统启动的早期，并且每次系统启动时都有应用而已。那么如何完成这种意义上的永久改变？答案是在编译内核的时候禁用相关功能，然后要后悔就只能重新编译内核了（悲）。）
|
||||
|
||||
一种让选项持续生效的方式是修改文件 **/etc/sysctl.conf**，在这里我用 vim 来编辑文件，不过你可以使用任何你想使用的编辑器，以及请确保你拥有**管理员权限**（用 **sudo**）：
|
||||
一种让选项持续生效的方式是修改文件 `/etc/sysctl.conf`，在这里我用 `vim` 来编辑文件，不过你可以使用任何你想使用的编辑器，以及请确保你拥有**管理员权限**（用 `sudo`）：
|
||||
|
||||
![Sysctl Configuration][10]
|
||||
|
||||
@ -92,7 +92,7 @@ net.ipv6.conf.lo.disable_ipv6=1
|
||||
sudo sysctl -p
|
||||
```
|
||||
|
||||
如果在重启之后 IPv6 仍然被启用了，而你还想继续这种方法的话，那么你必须（使用 root 权限）创建文件 **/etc/rc.local** 并加入以下内容：
|
||||
如果在重启之后 IPv6 仍然被启用了，而你还想继续这种方法的话，那么你必须（使用 root 权限）创建文件 `/etc/rc.local` 并加入以下内容：
|
||||
|
||||
```
|
||||
#!/bin/bash
|
||||
@ -112,20 +112,20 @@ sudo chmod 755 /etc/rc.local
|
||||
|
||||
这会让系统（在启动的时候）从之前编辑过的 sysctl 配置文件中读取内核参数。
|
||||
|
||||
#### 2\. 使用 GRUB 禁用 IPv6
|
||||
#### 2、使用 GRUB 禁用 IPv6
|
||||
|
||||
另外一种方法是配置 **GRUB**，它会在系统启动时向内核传递参数。这样做需要编辑文件 **/etc/default/grub**（请确保拥有管理员权限）。
|
||||
另外一种方法是配置 **GRUB**，它会在系统启动时向内核传递参数。这样做需要编辑文件 `/etc/default/grub`（请确保拥有管理员权限）。
|
||||
|
||||
![GRUB Configuration][13]
|
||||
|
||||
现在需要修改文件中分别以 **GRUB_CMDLINE_LINUX_DEFAULT** 和 **GRUB_CMDLINE_LINUX** 开头的两行来在启动时禁用 IPv6：
|
||||
现在需要修改文件中分别以 `GRUB_CMDLINE_LINUX_DEFAULT` 和 `GRUB_CMDLINE_LINUX` 开头的两行来在启动时禁用 IPv6：
|
||||
|
||||
```
|
||||
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash ipv6.disable=1"
|
||||
GRUB_CMDLINE_LINUX="ipv6.disable=1"
|
||||
```
|
||||
|
||||
（译注：这里是指在上述两行内增加参数 ipv6.disable=1，不同的系统中这两行的默认值可能有所不同。）
|
||||
（LCTT 译注：这里是指在上述两行内增加参数 `ipv6.disable=1`，不同的系统中这两行的默认值可能有所不同。）
|
||||
|
||||
保存文件，然后执行命令：
|
||||
|
||||
@ -133,7 +133,7 @@ GRUB_CMDLINE_LINUX="ipv6.disable=1"
|
||||
sudo update-grub
|
||||
```
|
||||
|
||||
（译注：该命令用以更新 GRUB 的配置文件，在没有 update-grub 命令的系统中需要使用 `sudo grub-mkconfig -o /boot/grub/grub.cfg` ）
|
||||
（LCTT 译注：该命令用以更新 GRUB 的配置文件，在没有 `update-grub` 命令的系统中需要使用 `sudo grub-mkconfig -o /boot/grub/grub.cfg` ）
|
||||
|
||||
设置会在重启后生效。
|
||||
|
||||
@ -147,7 +147,7 @@ sudo sysctl -w net.ipv6.conf.default.disable_ipv6=0
|
||||
sudo sysctl -w net.ipv6.conf.lo.disable_ipv6=0
|
||||
```
|
||||
|
||||
否则想要持续启用的话，看看是否修改过 **/etc/sysctl.conf**，可以删除掉之前增加的部分，也可以将它们改为以下值（两种方法等效）：
|
||||
否则想要持续启用的话，看看是否修改过 `/etc/sysctl.conf`，可以删除掉之前增加的部分，也可以将它们改为以下值（两种方法等效）：
|
||||
|
||||
```
|
||||
net.ipv6.conf.all.disable_ipv6=0
|
||||
@ -161,19 +161,19 @@ net.ipv6.conf.lo.disable_ipv6=0
|
||||
sudo sysctl -p
|
||||
```
|
||||
|
||||
（译注：这里可选的意思可能是如果之前临时启用了 IPv6 就没必要再重新加载配置文件了）
|
||||
（LCTT 译注：这里可选的意思可能是如果之前临时启用了 IPv6 就没必要再重新加载配置文件了）
|
||||
|
||||
这样应该可以再次看到 IPv6 地址了：
|
||||
|
||||
![IPv6 Reenabled in Ubuntu][14]
|
||||
|
||||
另外，你也可以删除之前创建的文件 **/etc/rc.local**（可选）：
|
||||
另外，你也可以删除之前创建的文件 `/etc/rc.local`（可选）：
|
||||
|
||||
```
|
||||
sudo rm /etc/rc.local
|
||||
```
|
||||
|
||||
如果修改了文件 **/etc/default/grub** ，回去删掉你所增加的参数：
|
||||
如果修改了文件 `/etc/default/grub`，回去删掉你所增加的参数：
|
||||
|
||||
```
|
||||
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"
|
||||
@ -186,7 +186,7 @@ GRUB_CMDLINE_LINUX=""
|
||||
sudo update-grub
|
||||
```
|
||||
|
||||
**尾声**
|
||||
### 尾声
|
||||
|
||||
在这篇文章中，我介绍了在 Linux 上**禁用 IPv6** 的方法，并简述了什么是 IPv6 以及可能想要禁用掉它的原因。
|
||||
|
||||
@ -199,7 +199,7 @@ via: https://itsfoss.com/disable-ipv6-ubuntu-linux/
|
||||
作者：[Sergiu][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[rakino](https://github.com/rakino)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
@ -212,11 +212,10 @@ via: https://itsfoss.com/disable-ipv6-ubuntu-linux/
|
||||
[5]: https://www.internetsociety.org/blog/2015/01/ipv6-security-myth-1-im-not-running-ipv6-so-i-dont-have-to-worry/
|
||||
[6]: https://itsfoss.com/remove-drive-icons-from-unity-launcher-in-ubuntu/
|
||||
[7]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2019/05/ipv6_address_ubuntu.png?fit=800%2C517&ssl=1
|
||||
[8]: https://itsfoss.com/restart-network-ubuntu/
|
||||
[8]: https://linux.cn/article-10804-1.html
|
||||
[9]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2019/05/ipv6_disabled_ubuntu.png?fit=800%2C442&ssl=1
|
||||
[10]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2019/05/sysctl_configuration.jpg?fit=800%2C554&ssl=1
|
||||
[11]: https://linuxhandbook.com/chmod-command/
|
||||
[12]: https://itsfoss.com/find-which-kernel-version-is-running-in-ubuntu/
|
||||
[13]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2019/05/grub_configuration-1.jpg?fit=800%2C565&ssl=1
|
||||
[14]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2019/05/ipv6_address_ubuntu-1.png?fit=800%2C517&ssl=1
|
||||
[patch-1]: https://github.com/LCTT/TranslateProject/blob/master/published/201905/20190307%20How%20to%20Restart%20a%20Network%20in%20Ubuntu%20-Beginner-s%20Tip.md
|
||||
380
published/20200512 Scan your Linux security with Lynis.md
Normal file
380
published/20200512 Scan your Linux security with Lynis.md
Normal file
@ -0,0 +1,380 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (wxy)
|
||||
[#]: reviewer: (wxy)
|
||||
[#]: publisher: (wxy)
|
||||
[#]: url: (https://linux.cn/article-12696-1.html)
|
||||
[#]: subject: (Scan your Linux security with Lynis)
|
||||
[#]: via: (https://opensource.com/article/20/5/linux-security-lynis)
|
||||
[#]: author: (Gaurav Kamathe https://opensource.com/users/gkamathe)
|
||||
|
||||
使用 Lynis 扫描 Linux 安全性
|
||||
======
|
||||
|
||||
> 使用这个全面的开源安全审计工具检查你的 Linux 机器的安全性。
|
||||
|
||||
|
||||
|
||||
你有没有想过你的 Linux 机器到底安全不安全？Linux 发行版众多，每个发行版都有自己的默认设置，你在上面运行着几十个版本各异的软件包，还有众多的服务在后台运行，而我们几乎不知道或不关心这些。
|
||||
|
||||
要想确定安全态势（指你的 Linux 机器上运行的软件、网络和服务的整体安全状态），你可以运行几个命令，得到一些零碎的相关信息，但你需要解析的数据量是巨大的。
|
||||
|
||||
如果能运行一个工具，生成一份关于机器安全状况的报告，那就好得多了。而幸运的是，有一个这样的软件：[Lynis][2]。它是一个非常流行的开源安全审计工具，可以帮助强化基于 Linux 和 Unix 的系统。根据该项目的介绍：
|
||||
|
||||
> “它运行在系统本身，可以进行深入的安全扫描。主要目标是测试安全防御措施，并提供进一步强化系统的提示。它还将扫描一般系统信息、易受攻击的软件包和可能的配置问题。Lynis 常被系统管理员和审计人员用来评估其系统的安全防御。”
|
||||
|
||||
### 安装 Lynis
|
||||
|
||||
你的 Linux 软件仓库中可能有 Lynis。如果有的话，你可以用以下方法安装它：
|
||||
|
||||
```
|
||||
dnf install lynis
|
||||
```
|
||||
|
||||
或
|
||||
|
||||
```
|
||||
apt install lynis
|
||||
```
|
||||
|
||||
然而，如果你的仓库中的版本不是最新的，你最好从 GitHub 上安装它。（我使用的是 Red Hat Linux 系统，但你可以在任何 Linux 发行版上运行它）。就像所有的工具一样，先在虚拟机上试一试是有意义的。要从 GitHub 上安装它：
|
||||
|
||||
```
|
||||
$ cat /etc/redhat-release
|
||||
Red Hat Enterprise Linux Server release 7.8 (Maipo)
|
||||
$
|
||||
$ uname -r
|
||||
3.10.0-1127.el7.x86_64
|
||||
$
|
||||
$ git clone https://github.com/CISOfy/lynis.git
|
||||
Cloning into 'lynis'...
|
||||
remote: Enumerating objects: 30, done.
|
||||
remote: Counting objects: 100% (30/30), done.
|
||||
remote: Compressing objects: 100% (30/30), done.
|
||||
remote: Total 12566 (delta 15), reused 8 (delta 0), pack-reused 12536
|
||||
Receiving objects: 100% (12566/12566), 6.36 MiB | 911.00 KiB/s, done.
|
||||
Resolving deltas: 100% (9264/9264), done.
|
||||
$
|
||||
```
|
||||
|
||||
一旦你克隆了这个版本库，那么进入该目录，看看里面有什么可用的。主要的工具在一个叫 `lynis` 的文件里。它实际上是一个 shell 脚本，所以你可以打开它看看它在做什么。事实上，Lynis 主要是用 shell 脚本来实现的：
|
||||
|
||||
```
|
||||
$ cd lynis/
|
||||
$ ls
|
||||
CHANGELOG.md CONTRIBUTING.md db developer.prf FAQ include LICENSE lynis.8 README SECURITY.md
|
||||
CODE_OF_CONDUCT.md CONTRIBUTORS.md default.prf extras HAPPY_USERS.md INSTALL lynis plugins README.md
|
||||
$
|
||||
$ file lynis
|
||||
lynis: POSIX shell script, ASCII text executable, with very long lines
|
||||
$
|
||||
```
|
||||
|
||||
### 运行 Lynis
|
||||
|
||||
通过给 Lynis 一个 `-h` 选项来查看帮助部分，以便有个大概了解：
|
||||
|
||||
```
|
||||
$ ./lynis -h
|
||||
```
|
||||
|
||||
你会看到一个简短的信息屏幕，然后是 Lynis 支持的所有子命令。
|
||||
|
||||
接下来，尝试一些测试命令以大致熟悉一下。要查看你正在使用的 Lynis 版本，请运行：
|
||||
|
||||
```
|
||||
$ ./lynis show version
|
||||
3.0.0
|
||||
$
|
||||
```
|
||||
|
||||
要查看 Lynis 中所有可用的命令：
|
||||
|
||||
```
|
||||
$ ./lynis show commands
|
||||
|
||||
Commands:
|
||||
lynis audit
|
||||
lynis configure
|
||||
lynis generate
|
||||
lynis show
|
||||
lynis update
|
||||
lynis upload-only
|
||||
|
||||
$
|
||||
```
|
||||
|
||||
### 审计 Linux 系统
|
||||
|
||||
要审计你的系统的安全态势，运行以下命令：
|
||||
|
||||
```
|
||||
$ ./lynis audit system
|
||||
```
|
||||
|
||||
这个命令运行得很快，并会返回一份详细的报告，输出结果可能一开始看起来很吓人，但我将在下面引导你来阅读它。这个命令的输出也会被保存到一个日志文件中，所以你可以随时回过头来检查任何可能感兴趣的东西。
|
||||
|
||||
Lynis 将日志保存在这里：
|
||||
|
||||
```
|
||||
Files:
|
||||
- Test and debug information : /var/log/lynis.log
|
||||
- Report data : /var/log/lynis-report.dat
|
||||
```
|
||||
|
||||
你可以验证是否创建了日志文件。它确实创建了：
|
||||
|
||||
```
|
||||
$ ls -l /var/log/lynis.log
|
||||
-rw-r-----. 1 root root 341489 Apr 30 05:52 /var/log/lynis.log
|
||||
$
|
||||
$ ls -l /var/log/lynis-report.dat
|
||||
-rw-r-----. 1 root root 638 Apr 30 05:55 /var/log/lynis-report.dat
|
||||
$
|
||||
```
|
||||
|
||||
### 探索报告
|
||||
|
||||
Lynis 提供了相当全面的报告，所以我将介绍一些重要的部分。作为初始化的一部分，Lynis 做的第一件事就是找出机器上运行的操作系统的完整信息。之后是检查是否安装了什么系统工具和插件：
|
||||
|
||||
```
|
||||
[+] Initializing program
|
||||
------------------------------------
|
||||
- Detecting OS... [ DONE ]
|
||||
- Checking profiles... [ DONE ]
|
||||
|
||||
---------------------------------------------------
|
||||
Program version: 3.0.0
|
||||
Operating system: Linux
|
||||
Operating system name: Red Hat Enterprise Linux Server 7.8 (Maipo)
|
||||
Operating system version: 7.8
|
||||
Kernel version: 3.10.0
|
||||
Hardware platform: x86_64
|
||||
Hostname: example
|
||||
---------------------------------------------------
|
||||
<<截断>>
|
||||
|
||||
[+] System Tools
|
||||
------------------------------------
|
||||
- Scanning available tools...
|
||||
- Checking system binaries...
|
||||
|
||||
[+] Plugins (phase 1)
|
||||
------------------------------------
|
||||
Note: plugins have more extensive tests and may take several minutes to complete
|
||||
|
||||
- Plugin: pam
|
||||
[..]
|
||||
- Plugin: systemd
|
||||
[................]
|
||||
```
|
||||
|
||||
接下来，该报告被分为不同的部分，每个部分都以 `[+]` 符号开头。下面可以看到部分章节。（哇，要审核的地方有这么多，Lynis 是最合适的工具！）
|
||||
|
||||
```
|
||||
[+] Boot and services
|
||||
[+] Kernel
|
||||
[+] Memory and Processes
|
||||
[+] Users, Groups and Authentication
|
||||
[+] Shells
|
||||
[+] File systems
|
||||
[+] USB Devices
|
||||
[+] Storage
|
||||
[+] NFS
|
||||
[+] Name services
|
||||
[+] Ports and packages
|
||||
[+] Networking
|
||||
[+] Printers and Spools
|
||||
[+] Software: e-mail and messaging
|
||||
[+] Software: firewalls
|
||||
[+] Software: webserver
|
||||
[+] SSH Support
|
||||
[+] SNMP Support
|
||||
[+] Databases
|
||||
[+] LDAP Services
|
||||
[+] PHP
|
||||
[+] Squid Support
|
||||
[+] Logging and files
|
||||
[+] Insecure services
|
||||
[+] Banners and identification
|
||||
[+] Scheduled tasks
|
||||
[+] Accounting
|
||||
[+] Time and Synchronization
|
||||
[+] Cryptography
|
||||
[+] Virtualization
|
||||
[+] Containers
|
||||
[+] Security frameworks
|
||||
[+] Software: file integrity
|
||||
[+] Software: System tooling
|
||||
[+] Software: Malware
|
||||
[+] File Permissions
|
||||
[+] Home directories
|
||||
[+] Kernel Hardening
|
||||
[+] Hardening
|
||||
[+] Custom tests
|
||||
```
|
||||
|
||||
Lynis 使用颜色编码使报告更容易解读。
|
||||
|
||||
* 绿色。一切正常
|
||||
* 黄色。跳过、未找到，可能有个建议
|
||||
* 红色。你可能需要仔细看看这个
|
||||
|
||||
在我的案例中，大部分的红色标记都是在 “Kernel Hardening” 部分找到的。内核有各种可调整的设置，它们定义了内核的功能，其中一些可调整的设置可能有其安全场景。发行版可能因为各种原因没有默认设置这些，但是你应该检查每一项，看看你是否需要根据你的安全态势来改变它的值：
|
||||
|
||||
```
|
||||
[+] Kernel Hardening
|
||||
------------------------------------
|
||||
- Comparing sysctl key pairs with scan profile
|
||||
- fs.protected_hardlinks (exp: 1) [ OK ]
|
||||
- fs.protected_symlinks (exp: 1) [ OK ]
|
||||
- fs.suid_dumpable (exp: 0) [ OK ]
|
||||
- kernel.core_uses_pid (exp: 1) [ OK ]
|
||||
- kernel.ctrl-alt-del (exp: 0) [ OK ]
|
||||
- kernel.dmesg_restrict (exp: 1) [ DIFFERENT ]
|
||||
- kernel.kptr_restrict (exp: 2) [ DIFFERENT ]
|
||||
- kernel.randomize_va_space (exp: 2) [ OK ]
|
||||
- kernel.sysrq (exp: 0) [ DIFFERENT ]
|
||||
- kernel.yama.ptrace_scope (exp: 1 2 3) [ DIFFERENT ]
|
||||
- net.ipv4.conf.all.accept_redirects (exp: 0) [ DIFFERENT ]
|
||||
- net.ipv4.conf.all.accept_source_route (exp: 0) [ OK ]
|
||||
- net.ipv4.conf.all.bootp_relay (exp: 0) [ OK ]
|
||||
- net.ipv4.conf.all.forwarding (exp: 0) [ OK ]
|
||||
- net.ipv4.conf.all.log_martians (exp: 1) [ DIFFERENT ]
|
||||
- net.ipv4.conf.all.mc_forwarding (exp: 0) [ OK ]
|
||||
- net.ipv4.conf.all.proxy_arp (exp: 0) [ OK ]
|
||||
- net.ipv4.conf.all.rp_filter (exp: 1) [ OK ]
|
||||
- net.ipv4.conf.all.send_redirects (exp: 0) [ DIFFERENT ]
|
||||
- net.ipv4.conf.default.accept_redirects (exp: 0) [ DIFFERENT ]
|
||||
- net.ipv4.conf.default.accept_source_route (exp: 0) [ OK ]
|
||||
- net.ipv4.conf.default.log_martians (exp: 1) [ DIFFERENT ]
|
||||
- net.ipv4.icmp_echo_ignore_broadcasts (exp: 1) [ OK ]
|
||||
- net.ipv4.icmp_ignore_bogus_error_responses (exp: 1) [ OK ]
|
||||
- net.ipv4.tcp_syncookies (exp: 1) [ OK ]
|
||||
- net.ipv4.tcp_timestamps (exp: 0 1) [ OK ]
|
||||
- net.ipv6.conf.all.accept_redirects (exp: 0) [ DIFFERENT ]
|
||||
- net.ipv6.conf.all.accept_source_route (exp: 0) [ OK ]
|
||||
- net.ipv6.conf.default.accept_redirects (exp: 0) [ DIFFERENT ]
|
||||
- net.ipv6.conf.default.accept_source_route (exp: 0) [ OK ]
|
||||
```
|
||||
|
||||
看看 SSH 这个例子，因为它是一个需要保证安全的关键领域。这里没有什么红色的东西，但是 Lynis 对我的环境给出了很多强化 SSH 服务的建议：
|
||||
|
||||
```
|
||||
[+] SSH Support
|
||||
------------------------------------
|
||||
- Checking running SSH daemon [ FOUND ]
|
||||
- Searching SSH configuration [ FOUND ]
|
||||
- OpenSSH option: AllowTcpForwarding [ SUGGESTION ]
|
||||
- OpenSSH option: ClientAliveCountMax [ SUGGESTION ]
|
||||
- OpenSSH option: ClientAliveInterval [ OK ]
|
||||
- OpenSSH option: Compression [ SUGGESTION ]
|
||||
- OpenSSH option: FingerprintHash [ OK ]
|
||||
- OpenSSH option: GatewayPorts [ OK ]
|
||||
- OpenSSH option: IgnoreRhosts [ OK ]
|
||||
- OpenSSH option: LoginGraceTime [ OK ]
|
||||
- OpenSSH option: LogLevel [ SUGGESTION ]
|
||||
- OpenSSH option: MaxAuthTries [ SUGGESTION ]
|
||||
- OpenSSH option: MaxSessions [ SUGGESTION ]
|
||||
- OpenSSH option: PermitRootLogin [ SUGGESTION ]
|
||||
- OpenSSH option: PermitUserEnvironment [ OK ]
|
||||
- OpenSSH option: PermitTunnel [ OK ]
|
||||
- OpenSSH option: Port [ SUGGESTION ]
|
||||
- OpenSSH option: PrintLastLog [ OK ]
|
||||
- OpenSSH option: StrictModes [ OK ]
|
||||
- OpenSSH option: TCPKeepAlive [ SUGGESTION ]
|
||||
- OpenSSH option: UseDNS [ SUGGESTION ]
|
||||
- OpenSSH option: X11Forwarding [ SUGGESTION ]
|
||||
- OpenSSH option: AllowAgentForwarding [ SUGGESTION ]
|
||||
- OpenSSH option: UsePrivilegeSeparation [ OK ]
|
||||
- OpenSSH option: AllowUsers [ NOT FOUND ]
|
||||
- OpenSSH option: AllowGroups [ NOT FOUND ]
|
||||
```
|
||||
|
||||
我的系统上没有运行虚拟机或容器，所以这些显示的结果是空的：
|
||||
|
||||
```
|
||||
[+] Virtualization
|
||||
------------------------------------
|
||||
|
||||
[+] Containers
|
||||
------------------------------------
|
||||
```
|
||||
|
||||
Lynis 会检查一些从安全角度看很重要的文件的文件权限：
|
||||
|
||||
```
|
||||
[+] File Permissions
|
||||
------------------------------------
|
||||
- Starting file permissions check
|
||||
File: /boot/grub2/grub.cfg [ SUGGESTION ]
|
||||
File: /etc/cron.deny [ OK ]
|
||||
File: /etc/crontab [ SUGGESTION ]
|
||||
File: /etc/group [ OK ]
|
||||
File: /etc/group- [ OK ]
|
||||
File: /etc/hosts.allow [ OK ]
|
||||
File: /etc/hosts.deny [ OK ]
|
||||
File: /etc/issue [ OK ]
|
||||
File: /etc/issue.net [ OK ]
|
||||
File: /etc/motd [ OK ]
|
||||
File: /etc/passwd [ OK ]
|
||||
File: /etc/passwd- [ OK ]
|
||||
File: /etc/ssh/sshd_config [ OK ]
|
||||
Directory: /root/.ssh [ SUGGESTION ]
|
||||
Directory: /etc/cron.d [ SUGGESTION ]
|
||||
Directory: /etc/cron.daily [ SUGGESTION ]
|
||||
Directory: /etc/cron.hourly [ SUGGESTION ]
|
||||
Directory: /etc/cron.weekly [ SUGGESTION ]
|
||||
Directory: /etc/cron.monthly [ SUGGESTION ]
|
||||
```
|
||||
|
||||
在报告的底部，Lynis 根据报告的发现提出了建议。每项建议后面都有一个 “TEST-ID”（为了下一部分方便，请将其保存起来）。
|
||||
|
||||
```
|
||||
Suggestions (47):
|
||||
----------------------------
|
||||
* If not required, consider explicit disabling of core dump in /etc/security/limits.conf file [KRNL-5820]
|
||||
https://cisofy.com/lynis/controls/KRNL-5820/
|
||||
|
||||
* Check PAM configuration, add rounds if applicable and expire passwords to encrypt with new values [AUTH-9229]
|
||||
https://cisofy.com/lynis/controls/AUTH-9229/
|
||||
```
|
||||
|
||||
Lynis 提供了一个选项来查找关于每个建议的更多信息，你可以使用 `show details` 命令和 TEST-ID 号来访问：
|
||||
|
||||
```
|
||||
./lynis show details TEST-ID
|
||||
```
|
||||
|
||||
这将显示该测试的其他信息。例如，我检查了 SSH-7408 的详细信息：
|
||||
|
||||
```
|
||||
$ ./lynis show details SSH-7408
|
||||
2020-04-30 05:52:23 Performing test ID SSH-7408 (Check SSH specific defined options)
|
||||
2020-04-30 05:52:23 Test: Checking specific defined options in /tmp/lynis.k8JwazmKc6
|
||||
2020-04-30 05:52:23 Result: added additional options for OpenSSH < 7.5
|
||||
2020-04-30 05:52:23 Test: Checking AllowTcpForwarding in /tmp/lynis.k8JwazmKc6
|
||||
2020-04-30 05:52:23 Result: Option AllowTcpForwarding found
|
||||
2020-04-30 05:52:23 Result: Option AllowTcpForwarding value is YES
|
||||
2020-04-30 05:52:23 Result: OpenSSH option AllowTcpForwarding is in a weak configuration state and should be fixed
|
||||
2020-04-30 05:52:23 Suggestion: Consider hardening SSH configuration [test:SSH-7408] [details:AllowTcpForwarding (set YES to NO)] [solution:-]
|
||||
```
|
||||
|
||||
### 试试吧
|
||||
|
||||
如果你想更多地了解你的 Linux 机器的安全性，请试试 Lynis。如果你想了解 Lynis 是如何工作的，可以研究一下它的 shell 脚本，看看它是如何收集这些信息的。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/20/5/linux-security-lynis
|
||||
|
||||
作者：[Gaurav Kamathe][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[wxy](https://github.com/wxy)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://opensource.com/users/gkamathe
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/yearbook-haff-rx-linux-file-lead_0.png?itok=-i0NNfDC (Hand putting a Linux file folder into a drawer)
|
||||
[2]: https://github.com/CISOfy/lynis
|
||||
@ -0,0 +1,140 @@
|
||||
[#]: collector: "lujun9972"
|
||||
[#]: translator: "lxbwolf"
|
||||
[#]: reviewer: "wxy"
|
||||
[#]: publisher: "wxy"
|
||||
[#]: url: "https://linux.cn/article-12700-1.html"
|
||||
[#]: subject: "Automate testing for website errors with this Python tool"
|
||||
[#]: via: "https://opensource.com/article/20/7/seodeploy"
|
||||
[#]: author: "JR Oakes https://opensource.com/users/jroakes"
|
||||
|
||||
使用这个 Python 工具对网站 SEO 问题进行自动化测试
|
||||
======
|
||||
|
||||
> SEODeploy 可以帮助我们在网站部署之前识别出 SEO 问题。
|
||||
|
||||
|
||||
|
||||
作为一个技术性搜索引擎优化开发者，我经常被请来协助做网站迁移、新网站发布、分析实施和其他一些影响网站在线可见性和测量等领域，以控制风险。许多公司每月经常性收入的很大一部分来自用户通过搜索引擎找到他们的产品和服务。虽然搜索引擎已经能妥善地处理没有被良好格式化的代码，但在开发过程中还是会出问题，对搜索引擎如何索引和为用户显示页面产生不利影响。
|
||||
|
||||
我曾经也尝试通过评审各阶段会破坏 SEO（<ruby>搜索引擎优化<rt>search engine optimization</rt></ruby>）的问题来手动降低这种风险。我的团队最终审查到的结果，决定了该项目是否可以上线。但这个过程通常很低效，只能用于有限的页面，而且很有可能出现人为错误。
|
||||
|
||||
长期以来，这个行业一直在寻找可用且值得信赖的方式来自动化这一过程，同时还能让开发人员和搜索引擎优化人员在必须测试的内容上获得有意义的发言权。这是非常重要的，因为这些团队在开发冲刺中优先级通常会发生冲突，搜索引擎优化者需要推动变化，而开发人员需要控制退化和预期之外的情况。
|
||||
|
||||
### 常见的破坏 SEO 的问题
|
||||
|
||||
我合作过的很多网站有成千上万的页面，甚至上百万。实在令人费解，为什么一个开发过程中的改动能影响这么多页面。在 SEO 的世界中，Google 或其他搜索引擎展示你的页面时，一个非常微小和看起来无关紧要的修改也可能导致全网站范围的变化。在部署到生产环境之前，必须要处理这类错误。
|
||||
|
||||
下面是我去年见过的几个例子。
|
||||
|
||||
#### 偶发的 noindex
|
||||
|
||||
在部署到生产环境之后，我们用的一个专用的第三方 SEO 监控工具 [ContentKing][2] 马上发现了这个问题。这个错误很隐蔽，因为它在 HTML 中是不可见的，确切地说，它隐藏在服务器响应头里，但它能很快导致搜索不可见。
|
||||
|
||||
```
|
||||
HTTP/1.1 200 OK
|
||||
Date: Tue May 25 2010 21:12:42 GMT
|
||||
[...]
|
||||
X-Robots-Tag: noindex
|
||||
[...]
|
||||
```
|
||||
|
||||
#### canonical 小写
|
||||
|
||||
上线时错误地把整个网站的 [canonical 链接元素][3]全改成小写了。这个改动影响了接近 30000 个 URL。在修改之前，所有的 URL 大小写都正常（例如 `URL-Path` 这样）。这之所以是个问题是因为 `canonical` 链接元素是用来给 Google 提示一个网页真实的规范 URL 版本的。这个改动导致很多 URL 被从 Google 的索引中移除并用小写的版本（`/url-path`）重新建立索引。影响范围是流量损失了 10% 到 15%，也污染了未来几个星期的网页监控数据。
|
||||
|
||||
#### 源站退化
|
||||
|
||||
有个网站的 React 实现复杂而奇特，它有个神奇的问题，`origin.domain.com` URL 退化显示为 CDN 服务器的源站。它会在网站元数据（如 `canonical` 链接元素、URL 和 Open Graph 链接）中间歇性地显示原始的主机而不是 CDN 边缘主机。这个问题在原始的 HTML 和渲染后的 HTML 中都存在。这个问题影响搜索的可见性和在社交媒体上的分享质量。
|
||||
|
||||
### SEODeploy 介绍
|
||||
|
||||
SEO 通常使用差异测试工具来检测渲染后和原始的 HTML 的差异。差异测试是很理想的，因为它避免了肉眼测试的不确定性。你希望检查 Google 对你的页面的渲染过程的差异，而不是检查用户对你页面的渲染。你希望查看下原始的 HTML 是什么样的，而不是渲染后的 HTML，因为 Google 的渲染过程是有独立的两个阶段的。
|
||||
|
||||
这促使我和我的同事创造了 [SEODeploy][4] 这个“在部署流水线中用于自动化 SEO 测试的 Python 库。”我们的使命是：
|
||||
|
||||
> 开发一个工具，让开发者能提供若干 URL 路径，并允许这些 URL 在生产环境和预演环境的主机上进行差异测试，尤其是对 SEO 相关数据的非预期的退化。
|
||||
|
||||
SEODeploy 的机制很简单：提供一个每行内容都是 URL 路径的文本文件，SEODeploy 对那些路径运行一系列模块，对比<ruby>生产环境<rt>production</rt></ruby>和<ruby>预演环境<rt>staging</rt></ruby>的 URL，把检测到的所有的错误和改动信息报告出来。
|
||||
|
||||
![SEODeploy overview][5]
|
||||
|
||||
这个工具及其模块可以用一个 YAML 文件来配置，可以根据预期的变化进行定制。
|
||||
|
||||
![SEODeploy output][7]
|
||||
|
||||
最初的发布版本包含下面的的核心功能和概念：
|
||||
|
||||
1. **开源**：我们坚信分享代码可以被大家批评、改进、扩展、分享和复用。
|
||||
2. **模块化**：Web 开发中有许多不同的堆栈和边缘案例。SEODeploy 工具在概念上很简单，因此采用模块化用来控制复杂性。我们提供了两个建好的模块和一个实例模块来简述基本结构。
|
||||
3. **URL 抽样**：由于它不是对所有 URL 都是可行和有效的，因此我们引入了一种随机抽取 XML 网站地图 URL 或被 ContentKing 监控的 URL 作为样本的方法。
|
||||
4. **灵活的差异检测**：Web 数据是凌乱的。无论被检测的数据是什么类型（如 ext、数组或列表、JSON 对象或字典、整数、浮点数等等），差异检测功能都会尝试将这些数据转换为差异信息。
|
||||
5. **自动化**: 你可以在命令行来调用抽样和运行方法，将 SEODeploy 融合到已有的流水线也很简单。
|
||||
|
||||
### 模块
|
||||
|
||||
虽然核心功能很简单，但在设计上，SEODeploy 的强大功能和复杂度体现在模块上。模块用来处理更难的任务：获取、清理和组织预演服务器和生产服务器上的数据来作对比。
|
||||
|
||||
#### Headless 模块
|
||||
|
||||
[Headless 模块][8] 是为那些从库里获取数据时不想为第三方服务付费的开发者准备的。它可以运行任意版本的 Chrome，会从每组用来比较的 URL 中提取渲染的数据。
|
||||
|
||||
Headless 模块会提取下面的核心数据用来比较：
|
||||
|
||||
1. SEO 内容，如标题、H1-H6、链接等等。
|
||||
2. 从 Chrome <ruby>计时器<rt>Timings</rt></ruby>和 CDP（<ruby>Chrome 开发工具协议<rt>Chrome DevTools Protocol</rt></ruby>）性能 API 中提取性能数据
|
||||
3. 计算出的性能指标，包括 CLS（<ruby>累积布局偏移<rt>Cumulative Layout Shift</rt></ruby>），这是 Google 最近发布的一个很受欢迎的 [Web 核心数据][9]
|
||||
4. 从上述 CDP 的覆盖率 API 获取的 CSS 和 JavaScript 的覆盖率数据
|
||||
|
||||
这个模块引入了处理预演环境、网络速度预设（为了让对比更规范化）等功能，也引入了一个处理在预演对比数据中替换预演主机的方法。开发者也能很容易地扩展这个模块，以收集他们想要在每个页面上进行比较的任何其他数据。
|
||||
|
||||
#### 其他模块
|
||||
|
||||
我们为开发者创建了一个[示例模块][10]，开发者可以参照它来使用框架创建一个自定义的提取模块。另一个示例模块是与 ContentKing 结合的。ContentKing 模块需要有 ContentKing 订阅，而 Headless 可以在所有能运行 Chrome 的机器上运行。
|
||||
|
||||
### 需要解决的问题
|
||||
|
||||
我们有扩展和强化工具库的[计划][11]，但正在寻求开发人员的[反馈][12]，了解哪些是可行的，哪些是不符合他们的需求。我们正在解决的问题和条目有：
|
||||
|
||||
1. 对于某些对比元素（尤其是 schema），动态时间戳会产生误报。
|
||||
2. 把测试数据保存到数据库，以便查看部署历史以及与上次的预演推送进行差异测试。
|
||||
3. 通过云基础设施的渲染，强化提取的规模和速度。
|
||||
4. 把测试覆盖率从现在的 46% 提高到 99% 以上。
|
||||
5. 目前，我们依赖 [Poetry][13] 进行部署管理，但我们希望发布一个 PyPl 库，这样就可以用 `pip install` 轻松安装。
|
||||
6. 我们还在关注更多使用时的问题和相关数据。
|
||||
|
||||
### 开始使用
|
||||
|
||||
这个项目在 [GitHub][4] 上，我们对大部分功能都提供了 [文档][14]。
|
||||
|
||||
我们希望你能克隆 SEODeploy 并试试它。我们的目标是通过这个由技术性搜索引擎优化开发者开发的、经过开发者和工程师们验证的工具来支持开源社区。我们都见过验证复杂的预演问题需要多长时间，也都见过大量 URL 的微小改动能有什么样的业务影响。我们认为这个库可以为开发团队节省时间、降低部署过程中的风险。
|
||||
|
||||
如果你有问题或者想提交代码，请查看项目的[关于][15]页面。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/20/7/seodeploy
|
||||
|
||||
作者：[JR Oakes][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[lxbwolf](https://github.com/lxbwolf)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://opensource.com/users/jroakes
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/browser_screen_windows_files.png?itok=kLTeQUbY "Computer screen with files or windows open"
|
||||
[2]: https://www.contentkingapp.com/
|
||||
[3]: https://en.wikipedia.org/wiki/Canonical_link_element
|
||||
[4]: https://github.com/locomotive-agency/SEODeploy
|
||||
[5]: https://opensource.com/sites/default/files/uploads/seodeploy.png "SEODeploy overview"
|
||||
[6]: https://creativecommons.org/licenses/by-sa/4.0/
|
||||
[7]: https://opensource.com/sites/default/files/uploads/seodeploy_output.png "SEODeploy output"
|
||||
[8]: https://locomotive-agency.github.io/SEODeploy/modules/headless/
|
||||
[9]: https://web.dev/vitals/
|
||||
[10]: https://locomotive-agency.github.io/SEODeploy/modules/creating/
|
||||
[11]: https://locomotive-agency.github.io/SEODeploy/todo/
|
||||
[12]: https://locomotive-agency.github.io/SEODeploy/about/#contact
|
||||
[13]: https://python-poetry.org/
|
||||
[14]: https://locomotive-agency.github.io/SEODeploy/
|
||||
[15]: https://locomotive-agency.github.io/SEODeploy/about/
|
||||
@ -1,8 +1,8 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (wxy)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: reviewer: (wxy)
|
||||
[#]: publisher: (wxy)
|
||||
[#]: url: (https://linux.cn/article-12697-1.html)
|
||||
[#]: subject: (How to read Lynis reports to improve Linux security)
|
||||
[#]: via: (https://opensource.com/article/20/8/linux-lynis-security)
|
||||
[#]: author: (Alan Formy-Duval https://opensource.com/users/alanfdoss)
|
||||
@ -12,13 +12,13 @@
|
||||
|
||||
> 使用 Lynis 的扫描和报告来发现和修复 Linux 安全问题。
|
||||
|
||||
![锁定][1]
|
||||
|
||||
|
||||
当我读到 Gaurav Kamathe 的文章《[用 Lynis 扫描你的 Linux 安全性][2]>时，让我想起了我在美国劳工部担任系统管理员的日子。我的职责之一是保证我们的 Unix 服务器的安全。每个季度，都会有一个独立的核查员来审查我们服务器的安全状态。每次在核查员预定到达的那一天，我都会运行 Security Readiness Review（SRR），这是一个扫描工具，它使用一大套脚本来识别和报告任何安全线索。SRR 是开源的，因此我可以查看所有源码脚本及其功能。这使我能够查看代码，确定具体是什么问题，并迅速修复它发现的每个问题。
|
||||
当我读到 Gaurav Kamathe 的文章《[使用 Lynis 扫描 Linux 安全性][2]》时，让我想起了我在美国劳工部担任系统管理员的日子。我那时的职责之一是保证我们的 Unix 服务器的安全。每个季度，都会有一个独立的核查员来审查我们服务器的安全状态。每次在核查员预定到达的那一天，我都会运行 Security Readiness Review（SRR），这是一个扫描工具，它使用一大套脚本来识别和报告任何安全线索。SRR 是开源的，因此我可以查看所有源码脚本及其功能。这使我能够查看其代码，确定具体是什么问题，并迅速修复它发现的每个问题。
|
||||
|
||||
### 什么是 Lynis？
|
||||
|
||||
[Lynis][3] 是一个开源的安全审计工具，它的工作原理和 SRR 很像，它会扫描 Linux 系统，并提供关于它发现的任何弱点的详细报告。同样和 SRR 一样，它也是由一大套脚本组成的，每个脚本都会检查一个特定的项目，例如，最小和最大密码时间要求。
|
||||
[Lynis][3] 是一个开源的安全审计工具，它的工作原理和 SRR 很像，它会扫描 Linux 系统，并提供它发现的任何弱点的详细报告。同样和 SRR 一样，它也是由一大套脚本组成的，每个脚本都会检查一个特定的项目，例如，最小和最大密码时间要求。
|
||||
|
||||
运行 Lynis 后，你可以使用它的报告来定位每个项目的脚本，并了解 Lynis 是如何检查和报告每个问题的。你也可以使用相同的脚本代码来创建新的代码来自动解决。
|
||||
|
||||
@ -61,14 +61,14 @@
|
||||
2020-06-16 20:54:33 ====
|
||||
```
|
||||
|
||||
这些细节表明 Lynis 无法找到各种文件。这个情况非常清楚。我可以运行 `updatedb` 命令，重新检查这个测试。
|
||||
这些细节表明 Lynis 无法找到各种文件。这个情况描述的非常清楚。我可以运行 `updatedb` 命令，然后重新检查这个测试。
|
||||
|
||||
```
|
||||
# updatedb
|
||||
# lynis --tests FILE-6410
|
||||
```
|
||||
|
||||
然后，重新检查细节时，会显示它发现哪个文件满足了测试：
|
||||
重新检查细节时，会显示它发现哪个文件满足了测试：
|
||||
|
||||
```
|
||||
# lynis show details FILE-6410
|
||||
@ -89,8 +89,8 @@ Lynis 的许多建议并不像这个建议那样直接。如果你不确定某
|
||||
|
||||
```
|
||||
* Consider hardening SSH configuration [SSH-7408]
|
||||
- Details : MaxAuthTries (6 --> 3)
|
||||
<https://cisofy.com/lynis/controls/SSH-7408/>
|
||||
- Details : MaxAuthTries (6 --> 3)
|
||||
https://cisofy.com/lynis/controls/SSH-7408/
|
||||
```
|
||||
|
||||
要解决这个问题，你需要知道 SSH 配置文件的位置。一个经验丰富的 Linux 管理员可能已经知道在哪里找到它们，但如果你不知道，有一个方法可以看到 Lynis 在哪里找到它们。
|
||||
@ -112,7 +112,7 @@ Lynis 支持多种操作系统，因此你的安装位置可能有所不同。
|
||||
|
||||
#### 查找 SSH 问题
|
||||
|
||||
名为 `tests_ssh` 的文件中包含了 TEST-ID，在这里可以找到与 SSH 相关的扫描函数。看看这个文件，就可以看到 Lynis 扫描器调用的各种函数。第一部分在一个名为 `SSH_DAEMON_CONFIG_LOCS` 的变量中定义了一个目录列表。下面几节负责检查 SSH 守护进程的状态、定位它的配置文件，并识别它的版本。我在 SSH-7404 测试中找到了查找配置文件的代码，描述为 “确定 SSH 守护进程配置文件位置”。这段代码包含一个 `for` 循环，在列表中的项目中搜索一个名为 `sshd_config` 的文件。我可以用这个逻辑来做自己的搜索：
|
||||
名为 `tests_ssh` 的文件中包含了 TEST-ID，在这里可以找到与 SSH 相关的扫描函数。看看这个文件，就可以看到 Lynis 扫描器调用的各种函数。第一部分在一个名为 `SSH_DAEMON_CONFIG_LOCS` 的变量中定义了一个目录列表。下面几节负责检查 SSH 守护进程的状态、定位它的配置文件，并识别它的版本。我在 SSH-7404 测试中找到了查找配置文件的代码，描述为 “确定 SSH 守护进程配置文件位置”。这段代码包含一个 `for` 循环，在列表中的项目中搜索一个名为 `sshd_config` 的文件。我可以用这个逻辑来自己进行搜索：
|
||||
|
||||
```
|
||||
# find /etc /etc/ssh /usr/local/etc/ssh /opt/csw/etc/ssh -name sshd_config
|
||||
@ -122,7 +122,7 @@ find: ‘/usr/local/etc/ssh’: No such file or directory
|
||||
find: ‘/opt/csw/etc/ssh’: No such file or directory
|
||||
```
|
||||
|
||||
进一步探索这个文件，就会发现寻找 SSH-7408 的相关代码。这个测试涵盖了 `MaxAuthTries` 和其他一些设置。现在我可以在 SSH 配置文件中找到该变量：
|
||||
进一步探索这个文件，就会看到寻找 SSH-7408 的相关代码。这个测试涵盖了 `MaxAuthTries` 和其他一些设置。现在我可以在 SSH 配置文件中找到该变量：
|
||||
|
||||
```
|
||||
# grep MaxAuthTries /etc/ssh/sshd_config
|
||||
@ -131,7 +131,7 @@ find: ‘/opt/csw/etc/ssh’: No such file or directory
|
||||
|
||||
#### 修复法律横幅问题
|
||||
|
||||
Lynis 还报告了一个与登录系统时显示的法律横幅有关的发现。在我的家庭桌面系统上（我不希望有很多其他人登录），我没有去改变默认的 `issue` 文件。企业或政府的系统很可能被要求包含一个法律横幅，以警告用户他们的登录和活动可能被记录和监控。Lynis 用 BANN-7126 测试和 BANN-7130 测试报告了这一点：
|
||||
Lynis 还报告了一个与登录系统时显示的法律横幅有关的发现。在我的家庭桌面系统上（我并不希望有很多其他人登录），我没有去改变默认的 `issue` 文件。企业或政府的系统很可能被要求包含一个法律横幅，以警告用户他们的登录和活动可能被记录和监控。Lynis 用 BANN-7126 测试和 BANN-7130 测试报告了这一点：
|
||||
|
||||
```
|
||||
* Add a legal banner to /etc/issue, to warn unauthorized users [BANN-7126]
|
||||
@ -168,7 +168,7 @@ Kernel \r on an \m (\l)
|
||||
for ITEM in ${LEGAL_BANNER_STRINGS}; do
|
||||
```
|
||||
|
||||
这些法律术语存储在文件顶部定义的变量 `LEGAL_BANNER_STRINGS` 中。向后滚动到顶部可以看到完整的清单：”
|
||||
这些法律术语存储在文件顶部定义的变量 `LEGAL_BANNER_STRINGS` 中。向后滚动到顶部可以看到完整的清单：
|
||||
|
||||
```
|
||||
LEGAL_BANNER_STRINGS="audit access authori condition connect consent continu criminal enforce evidence forbidden intrusion law legal legislat log monitor owner penal policy policies privacy private prohibited record restricted secure subject system terms warning"
|
||||
@ -205,12 +205,12 @@ via: https://opensource.com/article/20/8/linux-lynis-security
|
||||
作者：[Alan Formy-Duval][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[wxy](https://github.com/wxy)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://opensource.com/users/alanfdoss
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/security-lock-password.jpg?itok=KJMdkKum (Lock)
|
||||
[2]: https://opensource.com/article/20/5/linux-security-lynis
|
||||
[2]: https://linux.cn/article-12696-1.html
|
||||
[3]: https://github.com/CISOfy/lynis
|
||||
@ -1,46 +1,44 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (wxy)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: reviewer: (wxy)
|
||||
[#]: publisher: (wxy)
|
||||
[#]: url: (https://linux.cn/article-12688-1.html)
|
||||
[#]: subject: (What is IPv6, and why aren’t we there yet?)
|
||||
[#]: via: (https://www.networkworld.com/article/3254575/what-is-ipv6-and-why-aren-t-we-there-yet.html)
|
||||
[#]: author: (Keith Shaw, Josh Fruhlinger )
|
||||
|
||||
什么是 IPv6，为什么我们还普及？
|
||||
什么是 IPv6，为什么我们还未普及？
|
||||
======
|
||||
|
||||
自 1998 年以来，IPv6 一直在努力解决 IPv4 可用 IP 地址的不足的问题，然而尽管 IPv6 在效率和安全方面具有优势，但其采用速度仍然缓慢。
|
||||
> 自 1998 年以来，IPv6 一直在努力解决 IPv4 可用 IP 地址的不足的问题，然而尽管 IPv6 在效率和安全方面具有优势，但其采用速度仍然缓慢。
|
||||
|
||||
|
||||
|
||||
在大多数情况下，已经没人一再警告互联网地址耗尽的可怕境况，因为，虽然缓慢，但坚定地，从互联网协议版本 4（IPv4）的世界到 IPv6 的迁移已经开始，并且相关软件已经到位，以防止许多人预测的地址耗竭。
|
||||
在大多数情况下，已经没有人一再对互联网地址耗尽的可怕境况发出警告，因为，从互联网协议版本 4（IPv4）的世界到 IPv6 的迁移，虽然缓慢，但已经坚定地开始了，并且相关软件已经到位，以防止许多人预测的地址耗竭。
|
||||
|
||||
但在我们看到 IPv6 的现状和发展方向之前，让我们先回到互联网寻址的早期。
|
||||
|
||||
### 什么是 IPv6，为什么它很重要？
|
||||
|
||||
IPv6 是最新版本的<ruby>互联网协议<rt>Internet Protocol</rt></ruby>（IP），它可以识别互联网上的设备，从而确定它们的位置。每一个使用互联网的设备都要通过自己的 IP 地址来识别，以便互联网通信工作。在这方面，它就像你需要知道的街道地址和邮政编码一样，以便邮寄信件。
|
||||
IPv6 是最新版本的<ruby>互联网协议<rt>Internet Protocol</rt></ruby>（IP），它可以跨互联网识别设备，从而确定它们的位置。每一个使用互联网的设备都要通过自己的 IP 地址来识别，以便可以通过互联网通信。在这方面，它就像你需要知道街道地址和邮政编码一样，以便邮寄信件。
|
||||
|
||||
之前的版本 IPv4 采用 32 位寻址方案，可以支持 43 亿台设备，本以为已经足够。然而，互联网、个人电脑、智能手机以及现在物联网设备的发展证明，这个世界需要更多的地址。
|
||||
|
||||
幸运的是，<ruby>互联网工程任务组<rt>Internet Engineering Task Force</rt></ruby>（IETF）在 20 年前就认识到了这一点。1998 年，它创建了 IPv6，使用 128 位寻址方式来支持大约 340 <ruby>亿亿亿<rt>trillion trillion</rt></ruby>（或者 2 的 128 次幂，如果你喜欢的话）。IPv4 的地址可表示为四组一至三位十进制数，IPv6 则使用八组四位十六进制数字，用冒号隔开。
|
||||
幸运的是，<ruby>互联网工程任务组<rt>Internet Engineering Task Force</rt></ruby>（IETF）在 20 年前就认识到了这一点。1998 年，它创建了 IPv6，使用 128 位寻址方式来支持大约 340 <ruby>亿亿亿<rt>trillion trillion</rt></ruby>（或者 2 的 128 次幂，如果你喜欢用这种表示方式的话）。IPv4 的地址可表示为四组一至三位十进制数，IPv6 则使用八组四位十六进制数字，用冒号隔开。
|
||||
|
||||
### IPv6 的好处是什么？
|
||||
|
||||
IETF 在其工作中加入了 IPv6 对 IPv4 增强的功能。IPv6 协议可以更有效地处理数据包，提高性能和增加安全性。它使互联网服务提供商（ISP）能够通过使他们的路由表更有层次性来减少其大小。
|
||||
IETF 在其工作中为 IPv6 加入了对 IPv4 增强的功能。IPv6 协议可以更有效地处理数据包，提高性能和增加安全性。它使互联网服务提供商（ISP）能够通过使他们的路由表更有层次性来减少其大小。
|
||||
|
||||
### 网络地址转换（NAT）和 IPv6
|
||||
|
||||
IPv6 的采用被推迟，部分原因是<ruby>网络地址转换<rt>network address translation</rt></ruby>（NAT）导致的，它将私有 IP 地址转化为公共 IP 地址。这样一来，拥有私也 IP 地址的企业的机器就可以向位于私人网络之外拥有公共 IP 地址的机器发送和接收数据包。
|
||||
IPv6 的采用被推迟，部分原因是<ruby>网络地址转换<rt>network address translation</rt></ruby>（NAT）导致的，NAT 可以将私有 IP 地址转化为公共 IP 地址。这样一来，拥有私有 IP 地址的企业的机器就可以向位于私有网络之外拥有公共 IP 地址的机器发送和接收数据包。
|
||||
|
||||
如果没有 NAT，拥有数千台或数万台计算机的大公司如果要与外界通信，就会吞噬大量的公有 IPv4 地址。但是这些 IPv4 地址是有限的，而且接近枯竭，以至于不得不限制分配。
|
||||
|
||||
NAT 有助于缓解这个问题。有了 NAT，成千上万的私有地址计算机可以通过防火墙或路由器等 NAT 机器呈现在公共互联网上。
|
||||
NAT 有助于缓解这个问题。有了 NAT，成千上万的私有地址计算机可以通过防火墙或路由器等 NAT 设备呈现在公共互联网上。
|
||||
|
||||
NAT 的工作方式是，当一台拥有私有 IP 地址的企业计算机向企业网络外的公共 IP 地址发送数据包时，首先会进入 NAT 设备。NAT 在翻译表中记下数据包的源地址和目的地址。
|
||||
|
||||
NAT 将数据包的源地址改为 NAT 设备面向公众的地址，并将数据包一起发送到外部目的地。当数据包回复时，NAT 将目的地址翻译成发起通信的计算机的私有 IP 地址。这样一来，一个公网 IP 地址可以代表多台私有地址的计算机。
|
||||
NAT 的工作方式是，当一台拥有私有 IP 地址的企业计算机向企业网络外的公共 IP 地址发送数据包时，首先会进入 NAT 设备。NAT 在翻译表中记下数据包的源地址和目的地址。NAT 将数据包的源地址改为 NAT 设备面向公众的地址，并将数据包一起发送到外部目的地。当数据包回复时，NAT 将目的地址翻译成发起通信的计算机的私有 IP 地址。这样一来，一个公网 IP 地址可以代表多台私有地址的计算机。
|
||||
|
||||
### 谁在部署 IPv6？
|
||||
|
||||
@ -48,27 +46,27 @@ NAT 将数据包的源地址改为 NAT 设备面向公众的地址，并将数
|
||||
|
||||
主要网站则排在其后 —— World IPv6 Launch 称，目前 Alexa 前 1000 的网站中只有不到 30% 可以通过 IPv6 到达。
|
||||
|
||||
企业在部署方面比较落后，根据<ruby>互联网协会<rt>Internet Society</rt></ruby>的[《2017年 IPv6 部署状况》报告][4]，只有不到四分之一的企业宣传其 IPv6 前缀。复杂性、成本和完成迁移所需时间都是给出的理由。此外，一些项目由于软件兼容性的问题而被推迟。例如，一份 [2017 年 1 月的报告][5]称，Windows 10 中的一个 bug “破坏了微软在其西雅图总部推出纯 IPv6 网络的努力”。
|
||||
企业在部署方面比较落后，根据<ruby>互联网协会<rt>Internet Society</rt></ruby>的[《2017年 IPv6 部署状况》报告][4]，只有不到四分之一的企业宣传其 IPv6 前缀。复杂性、成本和完成迁移所需时间都是他们给出的理由。此外，一些项目由于软件兼容性的问题而被推迟。例如，一份 [2017 年 1 月的报告][5]称，Windows 10 中的一个 bug “破坏了微软在其西雅图总部推出纯 IPv6 网络的努力”。
|
||||
|
||||
### 何时会有更多部署？
|
||||
|
||||
互联网协会表示，IPv4 地址的价格将在 2018 年达到顶峰，然后在 IPv6 部署通过 50% 大关后，价格会下降。目前，[根据 Google][6]，全球的 IPv6 采用率为 20% 到 22%，但在美国约为 32%。
|
||||
|
||||
随着 IPv4 地址的价格开始下降，互联网协会建议企业出售现有的 IPv4 地址，以帮助资助其 IPv6 的部署。根据[一个发布在 GitHub 上的说明][7]，麻省理工学院已经这样做了。这所大学得出的结论是，其 800 万个 IPv4 地址是“过剩”的，可以在不影响当前或未来需求的情况下出售，因为它还持有 20 个<ruby>非亿级<rt>nonillion</rt></ruby> IPv6 地址。（非亿级地址是指数字 1 后面跟着 30 个零）。
|
||||
随着 IPv4 地址的价格开始下降，互联网协会建议企业出售现有的 IPv4 地址，以帮助资助其 IPv6 的部署。根据[一个发布在 GitHub 上的说明][7]，麻省理工学院已经这样做了。这所大学得出的结论是，其有 800 万个 IPv4 地址是“过剩”的，可以在不影响当前或未来需求的情况下出售，因为它还持有 20 个<ruby>非亿级<rt>nonillion</rt></ruby> IPv6 地址。（非亿级地址是指数字 1 后面跟着 30 个零）。
|
||||
|
||||
此外，随着部署的增多，更多的公司将开始对 IPv4 地址的使用收费，而免费提供 IPv6 服务。[英国的 ISP Mythic Beasts][8] 表示，“IPv6 连接是标配”，而 “IPv4 连接是可选的额外服务”。
|
||||
|
||||
### IPv4 何时会被“关闭”？
|
||||
|
||||
在 2011 年至 2018 年期间，世界上大部分地区[“用完”了新的 IPv4 地址][9] —— 但我们不会完全没有了这些地址，因为 IPv4 地址会被出售和重新使用（如前所述），而任何剩余的地址将用于 IPv6 过渡。
|
||||
在 2011 年至 2018 年期间，世界上大部分地区[“用完”了新的 IPv4 地址][9] —— 但我们不会完全没有 IPv4 地址，因为 IPv4 地址会被出售和重新使用（如前所述），而剩余的地址将用于 IPv6 过渡。
|
||||
|
||||
目前还没有正式的关闭日期，所以人们不应该担心有一天他们的互联网接入会突然消失。随着越来越多的网络过渡，越来越多的内容网站支持 IPv6，以及越来越多的终端用户为 IPv6 功能升级设备，世界将慢慢远离 IPv4。
|
||||
目前还没有正式的 IPv4 关闭日期，所以人们不用担心有一天他们的互联网接入会突然消失。随着越来越多的网络过渡，越来越多的内容网站支持 IPv6，以及越来越多的终端用户为 IPv6 功能升级设备，世界将慢慢远离 IPv4。
|
||||
|
||||
### 为什么没有 IPv5？
|
||||
|
||||
曾经有一个 IPv5，也被称为<ruby>互联网流协议<rt>Internet Stream Protocol</rt></ruby>，简称 ST。它被设计用于跨 IP 网络的面向连接的通信，目的是支持语音和视频。
|
||||
|
||||
它在这个任务上是成功的，并被实验性地使用。它的一个缺点是它的 32 位地址方案 —— 与 IPv4 使用的方案相同，从而影响了它的普及。因此，它存在着与 IPv4 相同的问题 —— 可用的 IP 地址数量有限。这导致了 IPv6 的发展和最终采用。尽管 IPv5 从未被公开采用，但它已经用掉了 IPv5 这个名字。
|
||||
它在这个任务上是成功的，并被实验性地使用。它的一个缺点是它的 32 位地址方案 —— 与 IPv4 使用的方案相同，从而影响了它的普及。因此，它存在着与 IPv4 相同的问题 —— 可用的 IP 地址数量有限。这导致了发展出了 IPv6 并和最终得到采用。尽管 IPv5 从未被公开采用，但它已经用掉了 IPv5 这个名字。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
@ -77,7 +75,7 @@ via: https://www.networkworld.com/article/3254575/what-is-ipv6-and-why-aren-t-we
|
||||
作者：[Keith Shaw][a],[Josh Fruhlinger][c]
|
||||
选题：[lujun9972][b]
|
||||
译者：[wxy](https://github.com/wxy)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
@ -1,8 +1,8 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (gxlct008)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: reviewer: (wxy)
|
||||
[#]: publisher: (wxy)
|
||||
[#]: url: (https://linux.cn/article-12693-1.html)
|
||||
[#]: subject: (Create a mobile app with Flutter)
|
||||
[#]: via: (https://opensource.com/article/20/9/mobile-app-flutter)
|
||||
[#]: author: (Vitaly Kuprenko https://opensource.com/users/kooper)
|
||||
@ -10,14 +10,15 @@
|
||||
使用 Flutter 创建 App
|
||||
======
|
||||
|
||||
使用流行的 Flutter 框架开始您的跨平台开发之旅。
|
||||
![A person looking at a phone][1]
|
||||
> 使用流行的 Flutter 框架开始你的跨平台开发之旅。
|
||||
|
||||
[Flutter][2] 是一个深受全球移动开发者欢迎的项目。该框架有一个庞大的、友好的发烧友社区，随着 Flutter 帮助程序员将他们的项目带入移动领域，这个社区还在继续增长。
|
||||
|
||||
|
||||
本教程旨在帮助您开始使用 Flutter 进行移动开发。阅读之后，您将了解如何快速安装和设置框架，以便开始为智能手机、平板电脑和其他平台编码。
|
||||
[Flutter][2] 是一个深受全球移动开发者欢迎的项目。该框架有一个庞大的、友好的爱好者社区，随着 Flutter 帮助程序员将他们的项目带入移动领域，这个社区还在继续增长。
|
||||
|
||||
本操作指南假定您已在计算机上安装了 [Android Studio][3]，并且具有一定的使用经验。
|
||||
本教程旨在帮助你开始使用 Flutter 进行移动开发。阅读之后，你将了解如何快速安装和设置框架，以便开始为智能手机、平板电脑和其他平台开发。
|
||||
|
||||
本操作指南假定你已在计算机上安装了 [Android Studio][3]，并且具有一定的使用经验。
|
||||
|
||||
### 什么是 Flutter ？
|
||||
|
||||
@ -25,15 +26,15 @@ Flutter 使得开发人员能够为多个平台构建应用程序，包括：
|
||||
|
||||
* Android
|
||||
* iOS
|
||||
* Web (测试版)
|
||||
* macOS (正在开发中)
|
||||
* Linux (正在开发中)
|
||||
* Web（测试版）
|
||||
* macOS（正在开发中）
|
||||
* Linux（正在开发中）
|
||||
|
||||
对 macOS 和 Linux 的支持还处于早期开发阶段，而 Web 支持预计很快就会发布。这意味着您可以立即试用其功能（如下所述）。
|
||||
对 macOS 和 Linux 的支持还处于早期开发阶段，而 Web 支持预计很快就会发布。这意味着你可以立即试用其功能（如下所述）。
|
||||
|
||||
### 安装 Flutter
|
||||
|
||||
我使用的是 Ubuntu18.04，但安装过程与其他 Linux 发行版类似，比如 Arch 或 Mint。
|
||||
我使用的是 Ubuntu 18.04，但其他 Linux 发行版安装过程与之类似，比如 Arch 或 Mint。
|
||||
|
||||
#### 使用 snapd 安装
|
||||
|
||||
@ -46,31 +47,27 @@ $ sudo snap install flutter –classic
|
||||
flutter 0+git.142868f from flutter Team/ installed
|
||||
```
|
||||
|
||||
然后使用 `flutter` 命令启动它。 首次启动时，该框架会下载到您的计算机上：
|
||||
然后使用 `flutter` 命令启动它。 首次启动时，该框架会下载到你的计算机上：
|
||||
|
||||
```
|
||||
$ flutter
|
||||
Initializing Flutter
|
||||
Downloading <https://storage.googleapis.com/flutter\_infra\[...\]>
|
||||
Downloading https://storage.googleapis.com/flutter_infra[...]
|
||||
```
|
||||
|
||||
下载完成后，您会看到一条消息，告诉您 Flutter 已初始化：
|
||||
下载完成后，你会看到一条消息，告诉你 Flutter 已初始化：
|
||||
|
||||
![Flutter initialized][5]
|
||||
|
||||
(Vitaly Kuprenko, [CC BY-SA 4.0][6])
|
||||
|
||||
#### 手动安装
|
||||
|
||||
如果您没有安装 Snapd，或者您的发行版不是 Ubuntu，那么安装过程会略有不同。 在这种情况下，请[下载] [7] 为您的操作系统推荐的 Flutter 版本。
|
||||
如果你没有安装 Snapd，或者你的发行版不是 Ubuntu，那么安装过程会略有不同。在这种情况下，请[下载][7] 为你的操作系统推荐的 Flutter 版本。
|
||||
|
||||
![Install Flutter manually][8]
|
||||
|
||||
(Vitaly Kuprenko, [CC BY-SA 4.0][6])
|
||||
然后将其解压缩到你的主目录。
|
||||
|
||||
然后将其解压缩到您的主目录。
|
||||
|
||||
在您喜欢的文本编辑器中打开主目录中的 `.bashrc` 文件 (如果您使用 [Z shell][9]，则打开 `.zshc`)。因为它是隐藏文件，所以您必须首先在文件管理器中启用显示隐藏文件，或者使用以下命令从终端打开它：
|
||||
在你喜欢的文本编辑器中打开主目录中的 `.bashrc` 文件（如果你使用 [Z shell][9]，则打开 `.zshc`）。因为它是隐藏文件，所以你必须首先在文件管理器中启用显示隐藏文件，或者使用以下命令从终端打开它：
|
||||
|
||||
```
|
||||
$ gedit ~/.bashrc &
|
||||
@ -82,48 +79,43 @@ $ gedit ~/.bashrc &
|
||||
export PATH="$PATH:~/flutter/bin"
|
||||
```
|
||||
|
||||
保存并关闭文件。 请记住，如果将 Flutter 提取到您的主目录之外的其他位置，则 [Flutter SDK 的路径][10] 将有所不同。
|
||||
保存并关闭文件。 请记住，如果在你的主目录之外的其他位置解压 Flutter，则 [Flutter SDK 的路径][10] 将有所不同。
|
||||
|
||||
关闭您的终端，然后再次打开，以便加载新配置。 或者，您可以通过以下命令使配置立即生效：
|
||||
关闭你的终端，然后再次打开，以便加载新配置。 或者，你可以通过以下命令使配置立即生效：
|
||||
|
||||
```
|
||||
$ . ~/.bashrc
|
||||
```
|
||||
|
||||
如果您没有看到错误，那说明一切都是正常的。
|
||||
|
||||
这种安装方法比使用 `snap`命令稍微困难一些，但是它非常通用，可以让您在几乎所有的发行版上安装框架。
|
||||
如果你没有看到错误，那说明一切都是正常的。
|
||||
|
||||
这种安装方法比使用 `snap` 命令稍微困难一些，但是它非常通用，可以让你在几乎所有的发行版上安装该框架。
|
||||
|
||||
#### 检查安装结果
|
||||
|
||||
要检查结果，请在终端中输入以下内容：
|
||||
要检查安装结果，请在终端中输入以下内容：
|
||||
|
||||
```
|
||||
flutter doctor -v
|
||||
```
|
||||
|
||||
您将看到有关已安装组件的信息。 如果看到错误，请不要担心。 您尚未安装任何用于 Flutter SDK 的 IDE 插件。
|
||||
你将看到有关已安装组件的信息。 如果看到错误，请不要担心。 你尚未安装任何用于 Flutter SDK 的 IDE 插件。
|
||||
|
||||
![Checking Flutter installation with the doctor command][11]
|
||||
|
||||
(Vitaly Kuprenko, [CC BY-SA 4.0][6])
|
||||
|
||||
### 安装 IDE 插件
|
||||
|
||||
您应该在您的 [集成开发环境 (IDE)][12] 中安装插件，以帮助它与 Flutter SDK 接口、与设备交互并构建代码。
|
||||
你应该在你的 [集成开发环境（IDE）][12] 中安装插件，以帮助它与 Flutter SDK 接口、与设备交互并构建代码。
|
||||
|
||||
Flutter 开发中常用的三个主要 IDE 工具是 IntelliJ IDEA (社区版)、Android Studio 和 VS Code (或 [VSCodium][13])。我在本教程中使用的是 Android Studio，但步骤与它们在 IntelliJ Idea (社区版)上的工作方式相似，因为它们构建在相同的平台上。
|
||||
Flutter 开发中常用的三个主要 IDE 工具是 IntelliJ IDEA（社区版）、Android Studio 和 VS Code（或 [VSCodium][13]）。我在本教程中使用的是 Android Studio，但步骤与它们在 IntelliJ Idea（社区版）上的工作方式相似，因为它们构建在相同的平台上。
|
||||
|
||||
首先，启动 **Android Studio**。打开 **Settings**，进入 **Plugins** 窗格，选择 **Marketplace** 选项卡。在搜索行中输入 **Flutter**，然后单击 **Install**。
|
||||
首先，启动 Android Studio。打开 “Settings”，进入 “Plugins” 窗格，选择 “Marketplace” 选项卡。在搜索行中输入 “Flutter”，然后单击 “Install”。
|
||||
|
||||
![Flutter plugins][14]
|
||||
|
||||
(Vitaly Kuprenko, [CC BY-SA 4.0][6])
|
||||
你可能会看到一个安装 “Dart” 插件的选项；同意它。如果看不到 Dart 选项，请通过重复上述步骤手动安装它。我还建议使用 “Rainbow Brackets” 插件，它可以让代码导航更简单。
|
||||
|
||||
您可能会看到一个安装 **Dart** 插件的选项；同意它。如果看不到 Dart 选项，请通过重复上述步骤手动安装。我还建议使用 **Rainbow Brackets** 插件，它可以让代码导航更简单。
|
||||
|
||||
就这样！您已经安装了所需的所有插件。您可以在终端中输入一个熟悉的命令进行检查：
|
||||
就这样！你已经安装了所需的所有插件。你可以在终端中输入一个熟悉的命令进行检查：
|
||||
|
||||
```
|
||||
flutter doctor -v
|
||||
@ -131,47 +123,37 @@ flutter doctor -v
|
||||
|
||||
![Checking Flutter plugins with the doctor command][15]
|
||||
|
||||
(Vitaly Kuprenko, [CC BY-SA 4.0][6])
|
||||
|
||||
### 构建您的 “Hello World” 应用程序
|
||||
### 构建你的 “Hello World” 应用程序
|
||||
|
||||
要启动新项目，请创建一个 Flutter 项目：
|
||||
|
||||
1. 选择 **New -> New Flutter project**.
|
||||
1、选择 “New -> New Flutter project”。
|
||||
|
||||
![Creating a new Flutter plugin][16]
|
||||
|
||||
(Vitaly Kuprenko, [CC BY-SA 4.0][6])
|
||||
2、在窗口中，选择所需的项目类型。 在这种情况下，你需要选择 “Flutter Application”。
|
||||
|
||||
2. 在窗口中，选择所需的项目类型。 在这种情况下，您需要选择 **Flutter Application**。
|
||||
|
||||
3. 命名您的项目 **hello_world**。 请注意，您应该使用合并的名称，因此请使用下划线而不是空格。 您可能还需要指定 SDK 的路径。
|
||||
3、命名你的项目为 `hello_world`。 请注意，你应该使用合并的名称，因此请使用下划线而不是空格。 你可能还需要指定 SDK 的路径。
|
||||
|
||||
![Naming a new Flutter plugin][17]
|
||||
|
||||
(Vitaly Kuprenko, [CC BY-SA 4.0][6])
|
||||
4、输入软件包名称。
|
||||
|
||||
4. 输入软件包名称。
|
||||
|
||||
您已经创建了一个项目！现在，您可以在设备上或使用模拟器启动它。
|
||||
你已经创建了一个项目！现在，你可以在设备上或使用模拟器启动它。
|
||||
|
||||
![Device options in Flutter][18]
|
||||
|
||||
(Vitaly Kuprenko, [CC BY-SA 4.0][6])
|
||||
|
||||
选择您想要的设备，然后按 **运行**。稍后，您将看到结果。
|
||||
选择你想要的设备，然后按 “Run”。稍后，你将看到结果。
|
||||
|
||||
![Flutter demo on mobile device][19]
|
||||
|
||||
(Vitaly Kuprenko, [CC BY-SA 4.0][6])
|
||||
|
||||
现在你可以在一个 [中间项目][20] 上开始工作了。
|
||||
|
||||
### 尝试 Flutter for web
|
||||
|
||||
在安装 Flutter 的 Web 组件之前，您应该知道 Flutter 目前对 Web 应用程序的支持还很原始。 因此，将其用于复杂的项目并不是一个好主意。
|
||||
在安装 Flutter 的 Web 组件之前，你应该知道 Flutter 目前对 Web 应用程序的支持还很原始。 因此，将其用于复杂的项目并不是一个好主意。
|
||||
|
||||
默认情况下，基本 SDK 中不启用 Flutter for web。 要打开它，请转到 beta 频道。 为此，请在终端中输入以下命令：
|
||||
默认情况下，基本 SDK 中不启用 “Flutter for web”。 要打开它，请转到 beta 通道。 为此，请在终端中输入以下命令：
|
||||
|
||||
```
|
||||
flutter channel beta
|
||||
@ -179,8 +161,6 @@ flutter channel beta
|
||||
|
||||
![flutter channel beta output][21]
|
||||
|
||||
(Vitaly Kuprenko, [CC BY-SA 4.0][6])
|
||||
|
||||
接下来，使用以下命令根据 beta 分支升级 Flutter：
|
||||
|
||||
```
|
||||
@ -189,23 +169,19 @@ flutter upgrade
|
||||
|
||||
![flutter upgrade output][22]
|
||||
|
||||
(Vitaly Kuprenko, [CC BY-SA 4.0][6])
|
||||
|
||||
要使 Flutter for web 工作，请输入：
|
||||
要使 “Flutter for web” 工作，请输入：
|
||||
|
||||
```
|
||||
flutter config --enable-web
|
||||
```
|
||||
|
||||
重新启动 IDE；这有助于 Android Studio 索引新的 IDE 并重新加载设备列表。您应该会看到几个新设备：
|
||||
重新启动 IDE；这有助于 Android Studio 索引新的 IDE 并重新加载设备列表。你应该会看到几个新设备：
|
||||
|
||||
![Flutter for web device options][23]
|
||||
|
||||
(Vitaly Kuprenko, [CC BY-SA 4.0][6])
|
||||
选择 “Chrome” 会在浏览器中启动一个应用程序， “Web Server” 会提供指向你的 Web 应用程序的链接，你可以在任何浏览器中打开它。
|
||||
|
||||
选择 **Chrome** 会在浏览器中启动一个应用程序， **Web Server** 会提供指向您的 Web 应用程序的链接，您可以在任何浏览器中打开它。
|
||||
|
||||
不过，现在还不是急于开发的时候，因为您当前的项目不支持Web。要改进它，请打开项目根目录下的终端，然后输入：
|
||||
不过，现在还不是急于开发的时候，因为你当前的项目不支持 Web。要改进它，请打开项目根目录下的终端，然后输入：
|
||||
|
||||
```
|
||||
flutter create
|
||||
@ -213,25 +189,21 @@ flutter create
|
||||
|
||||
此命令重新创建项目，并添加 Web 支持。 现有代码不会被删除。
|
||||
|
||||
请注意，目录树已更改，现在有了一个 "web" 目录：
|
||||
请注意，目录树已更改，现在有了一个 `web` 目录：
|
||||
|
||||
![File tree with web directory][24]
|
||||
|
||||
(Vitaly Kuprenko, [CC BY-SA 4.0][6])
|
||||
|
||||
现在您可以开始工作了。 选择 **Chrome**，然后按 **Run**。 稍后，您会看到带有应用程序的浏览器窗口。
|
||||
现在你可以开始工作了。 选择 “Chrome”，然后按 “Run”。 稍后，你会看到带有应用程序的浏览器窗口。
|
||||
|
||||
![Flutter web app demo][25]
|
||||
|
||||
(Vitaly Kuprenko, [CC BY-SA 4.0][6])
|
||||
|
||||
恭喜你！ 您刚刚为浏览器启动了一个项目，并且可以像其他任何网站一样继续使用它。
|
||||
恭喜你！ 你刚刚为浏览器启动了一个项目，并且可以像其他任何网站一样继续使用它。
|
||||
|
||||
所有这些都来自同一代码库，因为 Flutter 使得几乎无需更改就可以为移动平台和 Web 编写代码。
|
||||
|
||||
### 用 Flutter 做更多的事情
|
||||
|
||||
Flutter 是用于移动开发的强大工具，而且它也是迈向跨平台开发的重要一步。 了解它，使用它，并将您的应用程序交付到所有平台！
|
||||
Flutter 是用于移动开发的强大工具，而且它也是迈向跨平台开发的重要一步。 了解它，使用它，并将你的应用程序交付到所有平台！
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
@ -239,8 +211,8 @@ via: https://opensource.com/article/20/9/mobile-app-flutter
|
||||
|
||||
作者：[Vitaly Kuprenko][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/gxlct008)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
译者：[gxlct008](https://github.com/gxlct008)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
@ -1,28 +1,29 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (HankChow)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: reviewer: (wxy)
|
||||
[#]: publisher: (wxy)
|
||||
[#]: url: (https://linux.cn/article-12686-1.html)
|
||||
[#]: subject: (A practical guide to learning awk)
|
||||
[#]: via: (https://opensource.com/article/20/9/awk-ebook)
|
||||
[#]: author: (Seth Kenlon https://opensource.com/users/seth)
|
||||
|
||||
awk 实用学习指南
|
||||
======
|
||||
下载我们的电子书，学习如何更好地使用 `awk`。
|
||||
![Person programming on a laptop on a building][1]
|
||||
|
||||
> 下载我们的电子书，学习如何更好地使用 `awk`。
|
||||
|
||||
|
||||
|
||||
在众多 [Linux][2] 命令中，`sed`、`awk` 和 `grep` 恐怕是其中最经典的三个命令了。它们引人注目或许是由于名字发音与众不同，也可能是它们无处不在，甚至是因为它们存在已久，但无论如何，如果要问哪些命令很有 Linux 风格，这三个命令是当之无愧的。其中 `sed` 和 `grep` 已经有很多简洁的标准用法了，但 `awk` 的使用难度却相对突出。
|
||||
|
||||
在日常使用中，通过 `sed` 实现字符串替换、通过 `grep` 实现过滤，这些都是司空见惯的操作了，但 `awk` 命令相对来说是用得比较少的。在我看来，可能的原因是大多数人都只使用 `sed` 或者 `grep` 的一些变体实现某些功能，例如：
|
||||
|
||||
在日常使用中，通过 `sed` 实现字符串替换、通过 `grep` 实现过滤，这些都是司空见惯的操作了，但 `awk` 命令相对来说是用得比较少的。在我看来，可能的原因是大多数人都只使用 `sed` 或者 `grep` 的一些变化实现某些功能，例如：
|
||||
|
||||
```
|
||||
$ sed -e 's/foo/bar/g' file.txt
|
||||
$ grep foo file.txt
|
||||
```
|
||||
|
||||
因此，尽管你可能会觉得 `sed` 和 `grep` 使用起来更加顺手，但实际上它们还有更多更强大的作用没有发挥出来。当然，我们没有必要在这两个命令上钻研得很深入，但我还是想理解自己是如何学习一个命令的。很多时候我会把一整串命令记住，但不会去了解其中的运行过程，这就让我产生了一种很熟悉命令的错觉，我可以随口说出某个命令的好几个选项参数，但这些参数具体有什么作用，以及它们的相关语法，我都并不明确。
|
||||
因此，尽管你可能会觉得 `sed` 和 `grep` 使用起来更加顺手，但实际上它们还有更多更强大的作用没有发挥出来。当然，我们没有必要在这两个命令上钻研得很深入，但我有时会好奇自己“学习”命令的方式。很多时候我会记住一整串命令“咒语”，而不会去了解其中的运作过程，这就让我产生了一种很熟悉命令的错觉，我可以随口说出某个命令的好几个选项参数，但这些参数具体有什么作用，以及它们的相关语法，我都并不明确。
|
||||
|
||||
这大概就是很多人对 `awk` 缺乏了解的原因了。
|
||||
|
||||
@ -34,7 +35,6 @@ $ grep foo file.txt
|
||||
|
||||
`awk` 的本质是将输入的内容看作是一个数组。当 `awk` 扫描一个文本文件时，会把每一行作为一条<ruby>记录<rt>record</rt></ruby>，每一条记录中又分割为多个<ruby>字段<rt>field</rt></ruby>。`awk` 记录了各条记录各个字段的信息，并通过内置变量 `NR`（记录数） 和 `NF`（字段数） 来调用相关信息。例如一下这个命令可以查看文件的行数：
|
||||
|
||||
|
||||
```
|
||||
$ awk 'END { print NR;}' example.txt
|
||||
36
|
||||
@ -42,15 +42,13 @@ $ awk 'END { print NR;}' example.txt
|
||||
|
||||
从上面的命令可以看出 `awk` 的基本语法，无论是一个单行命令还是一整个脚本，语法都是这样的：
|
||||
|
||||
|
||||
```
|
||||
`样式或关键字 { 操作 }`
|
||||
模式或关键字 { 操作 }
|
||||
```
|
||||
|
||||
在上面的例子中，`END` 是一个关键字而不是样式，与此类似的另一个关键字是 `BEGIN`。使用 `BEGIN` 或 `END` 可以让 `awk` 在解析内容前或解析内容后执行大括号中指定的操作。
|
||||
|
||||
你可以使用<ruby>样式<rt>pattern</rt></ruby>作为过滤器或限定符，这样 `awk` 只会对匹配样式的对应记录执行指定的操作。以下这个例子就是使用 `awk` 实现 `grep` 命令在文件中查找“Linux”字符串的功能：
|
||||
在上面的例子中，`END` 是一个关键字而不是模式，与此类似的另一个关键字是 `BEGIN`。使用 `BEGIN` 或 `END` 可以让 `awk` 在解析内容前或解析内容后执行大括号中指定的操作。
|
||||
|
||||
你可以使用<ruby>模式<rt>pattern</rt></ruby>作为过滤器或限定符，这样 `awk` 只会对匹配模式的对应记录执行指定的操作。以下这个例子就是使用 `awk` 实现 `grep` 命令在文件中查找“Linux”字符串的功能：
|
||||
|
||||
```
|
||||
$ awk '/Linux/ { print $0; }' os.txt
|
||||
@ -62,8 +60,7 @@ OS: Elementary Linux (10.1.2.5)
|
||||
OS: Elementary Linux (10.1.2.6)
|
||||
```
|
||||
|
||||
`awk` 会将文件中的每一行作为一条记录，将一条记录中的每个单词作为一个字段，默认情况下会按照空格作为<ruby>分隔符<rt>field separator</rt></ruby>（`FS`）切割出记录中的字段。如果想要使用其它内容作为分隔符，可以使用 `--field-separator` 选项指定分隔符：
|
||||
|
||||
`awk` 会将文件中的每一行作为一条记录，将一条记录中的每个单词作为一个字段，默认情况下会以空格作为<ruby>字段分隔符<rt>field separator</rt></ruby>（`FS`）切割出记录中的字段。如果想要使用其它内容作为分隔符，可以使用 `--field-separator` 选项指定分隔符：
|
||||
|
||||
```
|
||||
$ awk --field-separator ':' '/Linux/ { print $2; }' os.txt
|
||||
@ -77,7 +74,6 @@ $ awk --field-separator ':' '/Linux/ { print $2; }' os.txt
|
||||
|
||||
在上面的例子中，可以看到在 `awk` 处理后每一行的行首都有一个空格，那是因为在源文件中每个冒号（`:`）后面都带有一个空格。和 `cut` 有所不同的是，`awk` 可以指定一个字符串作为分隔符，就像这样：
|
||||
|
||||
|
||||
```
|
||||
$ awk --field-separator ': ' '/Linux/ { print $2; }' os.txt
|
||||
CentOS Linux (10.1.1.8)
|
||||
@ -92,26 +88,23 @@ Elementary Linux (10.1.2.6)
|
||||
|
||||
可以通过这样的语法在 `awk` 中自定义函数：
|
||||
|
||||
|
||||
```
|
||||
`函数名称(参数) { 操作 }`
|
||||
函数名称(参数) { 操作 }
|
||||
```
|
||||
|
||||
函数的好处在于只需要编写一次就可以多次复用，因此函数在脚本中起到的作用会比在构造单行命令时大。同时 `awk` 自身也带有很多预定义的函数，并且工作原理和其它编程语言或电子表格保持一致。你只需要了解函数需要接受什么参数，就可以放心使用了。
|
||||
函数的好处在于只需要编写一次就可以多次复用，因此函数在脚本中起到的作用会比在构造单行命令时大。同时 `awk` 自身也带有很多预定义的函数，并且工作原理和其它编程语言或电子表格一样。你只需要了解函数需要接受什么参数，就可以放心使用了。
|
||||
|
||||
`awk` 中提供了数学运算和字符串处理的相关函数。数学运算函数通常比较简单，传入一个数字，它就会传出一个结果：
|
||||
|
||||
|
||||
```
|
||||
$ awk 'BEGIN { print sqrt(1764); }'
|
||||
42
|
||||
```
|
||||
|
||||
而字符串处理函数则稍微复杂一点，但 [GNU awk 手册][3]中也有充足的文档。例如 `split()` 函数需要传入一个待分割的单一字段、一个数组用于存放分割结果，以及用于分割的<ruby>定界符<rt>delimiter</rt></ruby>。
|
||||
而字符串处理函数则稍微复杂一点，但 [GNU awk 手册][3]中也有充足的文档。例如 `split()` 函数需要传入一个待分割的单一字段、一个用于存放分割结果的数组，以及用于分割的<ruby>定界符<rt>delimiter</rt></ruby>。
|
||||
|
||||
例如前面示例中的输出内容，每条记录的末尾都包含了一个 IP 地址。由于变量 `NF` 代表的是每条记录的字段数量，刚好对应的是每条记录中最后一个字段的序号，因此可以通过引用 `NF` 将每条记录的最后一个字段传入 `split()` 函数：
|
||||
|
||||
|
||||
```
|
||||
$ awk --field-separator ': ' '/Linux/ { split($NF, IP, "."); print "subnet: " IP[3]; }' os.txt
|
||||
subnet: 1
|
||||
@ -122,13 +115,13 @@ subnet: 2
|
||||
subnet: 2
|
||||
```
|
||||
|
||||
实际上 `awk` 的功能还远远不止于此，你还可以跳出 `awk` 本身，通过命令管道和脚本来自定义更多功能。
|
||||
还有更多的函数，没有理由将自己限制在每个 `awk` 代码块中。你可以在终端中使用 `awk` 构建复杂的管道，也可以编写 `awk` 脚本来定义和使用你自己的函数。
|
||||
|
||||
### 下载电子书
|
||||
|
||||
使用 `awk` 本身就是一个学习 `awk` 的过程，即使某些操作使用 `sed`、`grep`、`cut`、`tr` 命令已经完全足够了，也可以尝试使用 `awk` 来实现。只要熟悉了 `awk`，就可以在 Bash 中自定义一些 `awk` 函数，进而解析复杂的数据。
|
||||
|
||||
[下载我们的电子书][4]学习并开始使用 `awk` 吧！
|
||||
[下载我们的这本电子书][4]（需注册）学习并开始使用 `awk` 吧！
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
@ -137,7 +130,7 @@ via: https://opensource.com/article/20/9/awk-ebook
|
||||
作者：[Seth Kenlon][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[HankChow](https://github.com/hankchow)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
215
published/20200908 How to install software with Ansible.md
Normal file
215
published/20200908 How to install software with Ansible.md
Normal file
@ -0,0 +1,215 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (MjSeven)
|
||||
[#]: reviewer: (wxy)
|
||||
[#]: publisher: (wxy)
|
||||
[#]: url: (https://linux.cn/article-12703-1.html)
|
||||
[#]: subject: (How to install software with Ansible)
|
||||
[#]: via: (https://opensource.com/article/20/9/install-packages-ansible)
|
||||
[#]: author: (Seth Kenlon https://opensource.com/users/seth)
|
||||
|
||||
如何使用 Ansible 安装软件
|
||||
======
|
||||
|
||||
> 使用 Ansible 剧本自动安装和更新设备上的软件。
|
||||
|
||||
|
||||
|
||||
Ansible 是系统管理员和开发人员用来保持计算机系统处于最佳状态的一种流行的自动化工具。与可扩展框架一样，[Ansible][2] 本身功能有限，它真正的功能体现在许多模块中。在某种程度上，Ansible 模块就是 [Linux][3] 系统的命令。它们针对特定问题提供解决方案，而维护计算机时的一项常见任务是使所有计算机的更新和一致。
|
||||
|
||||
我曾经使用软件包的文本列表来保持系统或多或少的同步：我会列出笔记本电脑上安装的软件包，然后将其与台式机或另一台服务器之间进行交叉参考，手动弥补差异。当然，在 Linux 机器上安装和维护应用程序是 Ansible 的一项基本功能，这意味着你可以在自己关心的计算机上列出所需的内容。
|
||||
|
||||
### 寻找正确的 Ansible 模块
|
||||
|
||||
Ansible 模块的数量非常庞大，如何找到能完成你任务的模块？在 Linux 中，你可以在应用程序菜单或 `/usr/bin` 中查找要运行的应用程序。使用 Ansible 时，你可以参考 [Ansible 模块索引][4]。
|
||||
|
||||
这个索引按照类别列出。稍加搜索，你就很可能找到所需的模块。对于包管理，[Packaging 模块][5]几乎适用于所有带包管理器的系统。
|
||||
|
||||
### 动手写一个 Ansible 剧本
|
||||
|
||||
首先，选择本地计算机上的包管理器。例如，如果你打算在运行 Fedora 的笔记本电脑上编写 Ansible 指令（在 Ansible 中称为“<ruby>剧本<rt>playbook</rt></ruby>”），那么从 `dnf` 模块开始。如果你在 Elementary OS 上编写，使用 `apt` 模块，以此类推。这样你就可以开始进行测试和验证，并可以在以后扩展到其它计算机。
|
||||
|
||||
第一步是创建一个代表你的剧本的目录。这不是绝对必要的，但这是一个好习惯。Ansible 只需要一个配置文件就可以运行在 YAML 中，但是如果你以后想要扩展剧本，你就可以通过改变目录和文件的方式来控制 Ansible。现在，只需创建一个名为 `install_packages` 或类似的目录：
|
||||
|
||||
```
|
||||
$ mkdir ~/install_packages
|
||||
```
|
||||
|
||||
你可以根据自己的喜好来命名 Ansible 的剧本，但通常将其命名为 `site.yml`：
|
||||
|
||||
```
|
||||
$ touch ~/install_packages/site.yml
|
||||
```
|
||||
|
||||
在你最喜欢的文本编辑器中打开 `site.yml`，添加以下内容：
|
||||
|
||||
```
|
||||
---
|
||||
- hosts: localhost
|
||||
tasks:
|
||||
- name: install packages
|
||||
become: true
|
||||
become_user: root
|
||||
dnf:
|
||||
state: present
|
||||
name:
|
||||
- tcsh
|
||||
- htop
|
||||
```
|
||||
|
||||
你必须调整使用的模块名称以匹配你使用的发行版。在此示例中，我使用 `dnf` 是因为我在 Fedora Linux 上编写剧本。
|
||||
|
||||
就像 Linux 终端中的命令一样，知道 **如何** 来调用 Ansible 模块就已经成功了一半。这个示例剧本遵循标准剧本格式：
|
||||
|
||||
* `hosts` 是一台或多台计算机。在本示例中，目标计算机是 `localhost`，即你当前正在使用的计算机（而不是你希望 Ansible 连接的远程系统）。
|
||||
* `tasks` 是你要在主机上执行的任务列表。
|
||||
* `name` 是任务的人性化名称。在这种情况下，我使用 `install packages`，因为这就是该任务正在做的事情。
|
||||
* `become` 允许 Ansible 更改运行此任务的用户。
|
||||
* `become_user` 允许 Ansible 成为 `root` 用户来运行此任务。这是必须的，因为只有 root 用户才能使用 `dnf` 安装应用程序。
|
||||
* `dnf` 是模块名称，你可以在 Ansible 网站上的模块索引中找到。
|
||||
|
||||
`dnf` 下的节点是 `dnf` 模块专用的。这是模块文档的关键所在。就像 Linux 命令的手册页一样，模块文档会告诉你可用的选项和所需的参数。
|
||||
|
||||
![Ansible 文档][6]
|
||||
|
||||
安装软件包是一个相对简单的任务，仅需要两个元素。`state` 选项指示 Ansible 检查系统上是否存在 **软件包**，而 `name` 选项列出要查找的软件包。Ansible 会针对机器的 **状态** 进行调整，因此模块指令始终意味着更改。假如 Ansible 扫描了系统状态，发现剧本里描述的系统（在本例中，`tcsh` 和 `htop` 存在）与实际状态存在冲突，那么 Ansible 的任务是进行必要的更改来使系统与剧本匹配。Ansible 可以通过 `dnf`（或 `apt` 或者其它任何包管理器）模块进行更改。
|
||||
|
||||
每个模块可能都有一组不同的选项，所以在编写剧本时，要经常参考模块文档。除非你对模块非常熟悉，否则这是期望模块完成工作的唯一合理方法。
|
||||
|
||||
### 验证 YAML
|
||||
|
||||
剧本是用 YAML 编写的。因为 YAML 遵循严格的语法，所以安装 `yamllint` 来检查剧本是很有帮助的。更妙的是，有一个专门针对 Ansible 的检查工具称为 `ansible-lint`，它专门为剧本而生。在继续之前，安装它。
|
||||
|
||||
在 Fedora 或 CentOs 上：
|
||||
|
||||
```
|
||||
$ sudo dnf ins tall yamllint python3-ansible-lint
|
||||
```
|
||||
|
||||
在 Debian、Elementary 或 Ubuntu 上，同样的：
|
||||
|
||||
```
|
||||
$ sudo apt install yamllint ansible-lint
|
||||
```
|
||||
|
||||
使用 `ansible-link` 来验证你的剧本。如果你无法使用 `ansible-lint`，你可以使用 `yamllint`。
|
||||
|
||||
```
|
||||
$ ansible-lint ~/install_packages/site.yml
|
||||
```
|
||||
|
||||
成功则不返回任何内容，但如果文件中有错误，则必须先修复它们，然后再继续。复制和粘贴过程中的常见错误包括在最后一行的末尾省略换行符、使用制表符而不是空格来缩进。在文本编辑器中修复它们，重新运行 `ansible-lint`，重复这个过程，直到 `ansible-lint` 或 `yamllint` 没有返回为止。
|
||||
|
||||
### 使用 Ansible 安装一个应用
|
||||
|
||||
现在你有了一个可验证的有效剧本，你终于可以在本地计算机上运行它了，因为你碰巧知道该剧本定义的任务需要 root 权限，所以在调用 Ansible 时必须使用 `--ask-become-pass` 选项，因此系统会提示你输入管理员密码。
|
||||
|
||||
开始安装：
|
||||
|
||||
```
|
||||
$ ansible-playbook --ask-become-pass ~/install_packages/site.yml
|
||||
BECOME password:
|
||||
PLAY [localhost] ******************************
|
||||
|
||||
TASK [Gathering Facts] ******************************
|
||||
ok: [localhost]
|
||||
|
||||
TASK [install packages] ******************************
|
||||
ok: [localhost]
|
||||
|
||||
PLAY RECAP ******************************
|
||||
localhost: ok=0 changed=2 unreachable=0 failed=0 [...]
|
||||
```
|
||||
|
||||
这些命令被执行后，目标系统将处于与剧本中描述的相同的状态。
|
||||
|
||||
### 在远程系统上安装应用程序
|
||||
|
||||
通过这么多操作来替换一个简单的命令可能会适得其反，但是 Ansible 的优势是它可以在你的所有系统中实现自动化。你可以使用条件语句使 Ansible 在不同的系统上使用特定的模块，但是现在，假定所有计算机都使用相同的包管理器。
|
||||
|
||||
要连接到远程系统，你必须在 `/etc/ansible/hosts` 文件中定义远程系统，该文件与 Ansible 是一起安装的，所以它已经存在了，但它可能是空的，除了一些解释性注释之外。使用 `sudo` 在你喜欢的文本编辑器中打开它。
|
||||
|
||||
你可以通过其 IP 地址或主机名（只要主机名可以解析）定义主机。例如，如果你已经在 `/etc/hosts` 中定义了 `liavara` 并可以成功 `ping` 通，那么你可以在 `/etc/ansible/hosts` 中将 `liavara` 设置为主机。或者，如果你正在运行一个域名服务器或 Avahi 服务器并且可以 `ping` 通 `liavara`，那么你就可以在 `/etc/ansible/hosts` 中定义它。否则，你必须使用它的 IP 地址。
|
||||
|
||||
你还必须成功地建立与目标主机的安全 shell（SSH）连接。最简单的方法是使用 `ssh-copy-id` 命令，但是如果你以前从未与主机建立 SSH 连接，[阅读我关于如何创建自动 SSH 连接的文章][8]。
|
||||
|
||||
一旦你在 `/etc/ansible/hosts` 文件中输入了主机名或 IP 地址后，你就可以在剧本中更改 `hosts` 定义：
|
||||
|
||||
```
|
||||
---
|
||||
- hosts: all
|
||||
tasks:
|
||||
- name: install packages
|
||||
become: true
|
||||
become_user: root
|
||||
dnf:
|
||||
state: present
|
||||
name:
|
||||
- tcsh
|
||||
- htop
|
||||
```
|
||||
|
||||
再次运行 `ansible-playbook`：
|
||||
|
||||
```
|
||||
$ ansible-playbook --ask-become-pass ~/install_packages/site.yml
|
||||
```
|
||||
|
||||
这次，剧本会在你的远程系统上运行。
|
||||
|
||||
如果你添加更多主机，则有许多方法可以过滤哪个主机执行哪个任务。例如，你可以创建主机组（服务器的 `webserves`，台式机的 `workstations`等）。
|
||||
|
||||
### 适用于混合环境的 Ansible
|
||||
|
||||
到目前为止，我们一直假定 Ansible 配置的所有主机都运行相同的操作系统（都是是使用 `dnf` 命令进行程序包管理的操作系统）。那么，如果你要管理不同发行版的主机，例如 Ubuntu（使用 `apt`）或 Arch（使用 `pacman`），或者其它的操作系统时，该怎么办？
|
||||
|
||||
只要目标操作系统具有程序包管理器（[MacOs 有 Homebrew][9]，[Windows 有 Chocolatey][10]），Ansible 就能派上用场。
|
||||
|
||||
这就是 Ansible 优势最明显的地方。在 shell 脚本中，你必须检查目标主机上有哪些可用的包管理器，即使使用纯 Python，也必须检查操作系统。Ansible 不仅内置了这些功能，而且还具有在剧本中使用命令结果的机制。你可以使用 `action` 关键字来执行由 Ansible 事实收集子系统提供的变量定义的任务，而不是使用 `dnf` 模块。
|
||||
|
||||
```
|
||||
---
|
||||
- hosts: all
|
||||
tasks:
|
||||
- name: install packages
|
||||
become: true
|
||||
become_user: root
|
||||
action: >
|
||||
{{ ansible_pkg_mgr }} name=htop,transmission state=present update_cache=yes
|
||||
```
|
||||
|
||||
`action` 关键字会加载目标插件。在本例中，它使用了 `ansible_pkg_mgr` 变量，该变量由 Ansible 在初始 **收集信息** 期间填充。你不需要告诉 Ansible 收集有关其运行操作系统的事实，所以很容易忽略这一点，但是当你运行一个剧本时，你会在默认输出中看到它：
|
||||
|
||||
```
|
||||
TASK [Gathering Facts] *****************************************
|
||||
ok: [localhost]
|
||||
```
|
||||
|
||||
`action` 插件使用来自这个探针的信息，使用相关的包管理器命令填充 `ansible_pkg_mgr`，以安装在 `name` 参数之后列出的程序包。使用 8 行代码，你可以克服在其它脚本选项中很少允许的复杂跨平台难题。
|
||||
|
||||
### 使用 Ansible
|
||||
|
||||
现在是 21 世纪，我们都希望我们的计算机设备能够互联并且相对一致。无论你维护的是两台还是 200 台计算机，你都不必一次又一次地执行相同的维护任务。使用 Ansible 来同步生活中的计算机设备，看看 Ansible 还能为你做些什么。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/20/9/install-packages-ansible
|
||||
|
||||
作者：[Seth Kenlon][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[MjSeven](https://github.com/MjSeven)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://opensource.com/users/seth
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/puzzle_computer_solve_fix_tool.png?itok=U0pH1uwj (Puzzle pieces coming together to form a computer screen)
|
||||
[2]: https://opensource.com/resources/what-ansible
|
||||
[3]: https://opensource.com/resources/linux
|
||||
[4]: https://docs.ansible.com/ansible/latest/modules/modules_by_category.html
|
||||
[5]: https://docs.ansible.com/ansible/latest/modules/list_of_packaging_modules.html
|
||||
[6]: https://opensource.com/sites/default/files/uploads/ansible-module.png (Ansible documentation)
|
||||
[7]: https://creativecommons.org/licenses/by-sa/4.0/
|
||||
[8]: https://opensource.com/article/20/8/how-ssh
|
||||
[9]: https://opensource.com/article/20/6/homebrew-mac
|
||||
[10]: https://opensource.com/article/20/3/chocolatey
|
||||
@ -1,8 +1,8 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (geekpi)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: reviewer: (wxy)
|
||||
[#]: publisher: (wxy)
|
||||
[#]: url: (https://linux.cn/article-12676-1.html)
|
||||
[#]: subject: (Installing and running Vagrant using qemu-kvm)
|
||||
[#]: via: (https://fedoramagazine.org/vagrant-qemukvm-fedora-devops-sysadmin/)
|
||||
[#]: author: (Andy Mott https://fedoramagazine.org/author/amott/)
|
||||
@ -12,47 +12,50 @@
|
||||
|
||||
![][1]
|
||||
|
||||
Vagrant 是一个出色的工具，被 DevOps 专业人员、程序员、系统管理员和普通极客来使用它来建立可复制的基础架构来进行开发和测试。来自它们的网站：
|
||||
Vagrant 是一个出色的工具，DevOps 专业人员、程序员、系统管理员和普通极客来使用它来建立可重复的基础架构来进行开发和测试。引用自它的网站：
|
||||
|
||||
> Vagrant 是用于在单工作流程中构建和管理虚拟机环境的工具。凭借简单易用的工作流程和对自动化的关注，Vagrant 降低了开发环境的设置时间，提高了生产效率，并使”在我的机器上工作“的借口成为过去。
|
||||
> Vagrant 是用于在单工作流程中构建和管理虚拟机环境的工具。凭借简单易用的工作流程并专注于自动化，Vagrant 降低了开发环境的设置时间，提高了生产效率，并使“在我的机器上可以工作”的借口成为过去。
|
||||
>
|
||||
> 如果你已经熟悉 Vagrant 的基础知识，那么文档为所有的功能和内部结构提供了更好的参考。
|
||||
> 如果你已经熟悉 Vagrant 的基础知识，那么该文档为所有的功能和内部结构提供了更好的参考。
|
||||
>
|
||||
> Vagrant 提供了易于配置、可复制、可移植的工作环境，它建立在行业标准技术之上，并由一个统一的工作流程控制，帮助你和你的团队最大限度地提高生产力和灵活性。
|
||||
> Vagrant 提供了基于行业标准技术构建的、易于配置、可复制、可移植的工作环境，并由一个一致的工作流程控制，帮助你和你的团队最大限度地提高生产力和灵活性。
|
||||
>
|
||||
> <https://www.vagrantup.com/intro>
|
||||
|
||||
本指南将通过必要的步骤，让 Vagrant 在基于 Fedora 的机器上工作。
|
||||
本指南将逐步介绍使 Vagrant 在基于 Fedora 的计算机上工作所需的步骤。
|
||||
|
||||
我从最小化安装 Fedora Server 开始，因为这样可以减少主机操作系统的内存占用，但如果你已经有一台可以使用的 Fedora 机器，无论是服务器还是工作站，那么也没问题。
|
||||
我从最小化安装 Fedora 服务器开始，因为这样可以减少宿主机操作系统的内存占用，但如果你已经有一台可以使用的 Fedora 机器，无论是服务器还是工作站版本，那么也没问题。
|
||||
|
||||
### 检查机器是否支持虚拟化：
|
||||
### 检查机器是否支持虚拟化
|
||||
|
||||
```
|
||||
$ sudo lscpu | grep Virtualization
|
||||
```
|
||||
|
||||
```
|
||||
Virtualization: VT-x
|
||||
Virtualization type: full
|
||||
```
|
||||
|
||||
### 安装 qemu-kvm：
|
||||
### 安装 qemu-kvm
|
||||
|
||||
```
|
||||
sudo dnf install qemu-kvm libvirt libguestfs-tools virt-install rsync
|
||||
```
|
||||
|
||||
### 启用并启动 libvirt 守护进程：
|
||||
### 启用并启动 libvirt 守护进程
|
||||
|
||||
```
|
||||
sudo systemctl enable --now libvirtd
|
||||
```
|
||||
|
||||
### 安装 Vagrant：
|
||||
### 安装 Vagrant
|
||||
|
||||
```
|
||||
sudo dnf install vagrant
|
||||
```
|
||||
|
||||
### 安装 Vagrant libvirtd 插件：
|
||||
### 安装 Vagrant libvirtd 插件
|
||||
|
||||
```
|
||||
sudo vagrant plugin install vagrant-libvirt
|
||||
@ -64,48 +67,58 @@ sudo vagrant plugin install vagrant-libvirt
|
||||
vagrant box add fedora/32-cloud-base --provider=libvirt
|
||||
```
|
||||
|
||||
### 创建一个最小的 Vagrantfile 来测试：
|
||||
（LCTT 译注：以防你不知道，box 是 Vagrant 中的一种包格式，Vagrant 支持的任何平台上的任何人都可以使用盒子来建立相同的工作环境。）
|
||||
|
||||
### 创建一个最小化的 Vagrantfile 来测试
|
||||
|
||||
```
|
||||
$ mkdir vagrant-test
|
||||
$ cd vagrant-test
|
||||
$ vi VagrantfileVagrant.configure("2") do |config|
|
||||
$ vi Vagrantfile
|
||||
```
|
||||
|
||||
```
|
||||
Vagrant.configure("2") do |config|
|
||||
config.vm.box = "fedora/32-cloud-base"
|
||||
end
|
||||
```
|
||||
|
||||
**注意文件名和文件内容的大写。**
|
||||
**注意文件名和文件内容的大小写。**
|
||||
|
||||
### 检查文件：
|
||||
### 检查文件
|
||||
|
||||
```
|
||||
vagrant statusCurrent machine states:
|
||||
vagrant status
|
||||
```
|
||||
|
||||
```
|
||||
Current machine states:
|
||||
|
||||
default not created (libvirt)
|
||||
|
||||
The Libvirt domain is not created. Run 'vagrant up' to create it.
|
||||
```
|
||||
|
||||
### 启动 box：
|
||||
### 启动 box
|
||||
|
||||
```
|
||||
vagrant up
|
||||
```
|
||||
|
||||
### 连接到你的新机器：
|
||||
### 连接到你的新机器
|
||||
|
||||
```
|
||||
vagrant ssh
|
||||
```
|
||||
|
||||
完成了。现在你的 Fedora 机器上有 Vagrant 在工作。
|
||||
完成了。现在你的 Fedora 机器上 Vagrant 可以工作了。
|
||||
|
||||
要停止机器，请使用 _vagrant halt_。这只是简单地停止机器，但保留虚拟机和磁盘。
|
||||
要关闭并删除它，请使用 _vagrant destroy_。这将删除整个机器和你在其中所做的任何更改。
|
||||
要停止该机器，请使用 `vagrant halt`。这只是简单地停止机器，但保留虚拟机和磁盘。
|
||||
要关闭并删除它，请使用 `vagrant destroy`。这将删除整个机器和你在其中所做的任何更改。
|
||||
|
||||
### 接下来的步骤
|
||||
|
||||
在运行 _vagrant up_ 命令之前，你不需要下载 box。你可以直接在 Vagrantfile 中指定 box 和提供者，如果还没有的话，Vagrant 会下载它。下面是一个例子，它还设置了内存量和 CPU 数量：
|
||||
在运行 `vagrant up` 命令之前，你不需要下载 box。你可以直接在 Vagrantfile 中指定 box 和提供者，如果还没有的话，Vagrant 会下载它。下面是一个例子，它还设置了内存量和 CPU 数量：
|
||||
|
||||
```
|
||||
# -*- mode: ruby -*-
|
||||
@ -131,7 +144,7 @@ via: https://fedoramagazine.org/vagrant-qemukvm-fedora-devops-sysadmin/
|
||||
作者：[Andy Mott][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[geekpi](https://github.com/geekpi)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
@ -1,8 +1,8 @@
|
||||
[#]: collector: "lujun9972"
|
||||
[#]: translator: "lxbwolf"
|
||||
[#]: reviewer: " "
|
||||
[#]: publisher: " "
|
||||
[#]: url: " "
|
||||
[#]: reviewer: "wxy"
|
||||
[#]: publisher: "wxy"
|
||||
[#]: url: "https://linux.cn/article-12681-1.html"
|
||||
[#]: subject: "Find security issues in Go code using gosec"
|
||||
[#]: via: "https://opensource.com/article/20/9/gosec"
|
||||
[#]: author: "Gaurav Kamathe https://opensource.com/users/gkamathe"
|
||||
@ -10,20 +10,21 @@
|
||||
使用 gosec 检查 Go 代码中的安全问题
|
||||
======
|
||||
|
||||
来学习下 Golang 的安全检查工具 gosec。
|
||||
![A lock on the side of a building][1]
|
||||
> 来学习下 Go 语言的安全检查工具 gosec。
|
||||
|
||||
|
||||
|
||||
[Go 语言][2]写的代码越来越常见，尤其是在容器、Kubernetes 或云生态相关的开发中。Docker 是最早采用 Golang 的项目之一，随后是 Kubernetes，之后大量的新项目在众多编程语言中选择了 Go。
|
||||
|
||||
像其他语言一样，Go 也有它的长处和短处（如安全缺陷）。这些缺陷可能会因为语言本身的限制在程序员编码不当时出现，例如，C 代码中的内存安全问题。
|
||||
像其他语言一样，Go 也有它的长处和短处（如安全缺陷）。这些缺陷可能会因为语言本身的缺陷加上程序员编码不当而产生，例如，C 代码中的内存安全问题。
|
||||
|
||||
无论它们出现的原因是什么，安全问题都应该在开发过程中尽早修复，以免在封装好的软件中出现。幸运的是，静态分析工具可以帮你批量地处理这些问题。静态分析工具通过解析用某种编程语言写的代码来找到问题。
|
||||
无论它们出现的原因是什么，安全问题都应该在开发过程的早期修复，以免在封装好的软件中出现。幸运的是，静态分析工具可以帮你以更可重复的方式处理这些问题。静态分析工具通过解析用某种编程语言写的代码来找到问题。
|
||||
|
||||
这类工具中很多被称为 linter。传统意义上，linter 更注重的是检查代码中编码问题、bug、代码风格之类的问题，不会检查安全问题。例如，[Coverity][3] 是很受欢迎的用来检查 C/C++ 代码问题的工具。然而，有工具专门用来检查源码中的安全问题。例如，[Bandit][4] 用来检查 Python 代码中的安全缺陷。[gosec][5] 用来搜寻 Go 源码中的安全缺陷。gosec 通过扫描 Go 的 AST（<ruby>抽象语法树<rt>abstract syntax tree</rt></ruby>）来检查源码中的安全问题。
|
||||
这类工具中很多被称为 linter。传统意义上，linter 更注重的是检查代码中编码问题、bug、代码风格之类的问题，它们可能不会发现代码中的安全问题。例如，[Coverity][3] 是一个很流行的工具，它可以帮助寻找 C/C++ 代码中的问题。然而，也有一些工具专门用来检查源码中的安全问题。例如，[Bandit][4] 可以检查 Python 代码中的安全缺陷。而 [gosec][5] 则用来搜寻 Go 源码中的安全缺陷。`gosec` 通过扫描 Go 的 AST（<ruby>抽象语法树<rt>abstract syntax tree</rt></ruby>）来检查源码中的安全问题。
|
||||
|
||||
### 开始使用 gosec
|
||||
|
||||
在开始学习和使用 gosec 之前，你需要准备一个 Go 语言写的项目。有这么多开源软件，我相信这不是问题。你可以在 GitHub 的 [Golang 库排行榜]][6]中找一个。
|
||||
在开始学习和使用 `gosec` 之前，你需要准备一个 Go 语言写的项目。有这么多开源软件，我相信这不是问题。你可以在 GitHub 的 [热门 Golang 仓库][6]中找一个。
|
||||
|
||||
本文中，我随机选了 [Docker CE][7] 项目，但你可以选择任意的 Go 项目。
|
||||
|
||||
@ -31,57 +32,45 @@
|
||||
|
||||
如果你还没安装 Go，你可以先从仓库中拉取下来。如果你用的是 Fedora 或其他基于 RPM 的 Linux 发行版本：
|
||||
|
||||
|
||||
```
|
||||
`$ dnf install golang.x86_64`
|
||||
$ dnf install golang.x86_64
|
||||
```
|
||||
|
||||
如果你用的是其他操作系统，请参照 [Golang 安装][8]页面。
|
||||
|
||||
使用 `version` 参数来验证 Go 是否安装成功：
|
||||
|
||||
|
||||
```
|
||||
$ go version
|
||||
go version go1.14.6 linux/amd64
|
||||
$
|
||||
```
|
||||
|
||||
运行 `go get` 命令就可以轻松地安装 gosec：
|
||||
|
||||
运行 `go get` 命令就可以轻松地安装 `gosec`：
|
||||
|
||||
```
|
||||
$ go get github.com/securego/gosec/cmd/gosec
|
||||
$
|
||||
```
|
||||
|
||||
上面这行命令会从 GitHub 下载 gosec 的源码、编译并安装到指定位置。在仓库的 README 中你还可以看到[安装工具的其他方法][9]。
|
||||
|
||||
gosec 的源码会被下载到 `$GOPATH` 的位置，编译出的二进制文件会被安装到你系统上设置的 `bin` 目录下。你可以运行下面的命令来查看 `$GOPATH` 和 `$GOBIN` 目录：
|
||||
上面这行命令会从 GitHub 下载 `gosec` 的源码，编译并安装到指定位置。在仓库的 `README` 中你还可以看到[安装该工具的其他方法][9]。
|
||||
|
||||
`gosec` 的源码会被下载到 `$GOPATH` 的位置，编译出的二进制文件会被安装到你系统上设置的 `bin` 目录下。你可以运行下面的命令来查看 `$GOPATH` 和 `$GOBIN` 目录：
|
||||
|
||||
```
|
||||
$ go env | grep GOBIN
|
||||
GOBIN="/root/go/gobin"
|
||||
$
|
||||
$ go env | grep GOPATH
|
||||
GOPATH="/root/go"
|
||||
$
|
||||
```
|
||||
|
||||
如果 `go get` 命令执行成功，那么 gosec 二进制应该就可以使用了：
|
||||
|
||||
如果 `go get` 命令执行成功，那么 `gosec` 二进制应该就可以使用了：
|
||||
|
||||
```
|
||||
$
|
||||
$ ls -l ~/go/bin/
|
||||
total 9260
|
||||
-rwxr-xr-x. 1 root root 9482175 Aug 20 04:17 gosec
|
||||
$
|
||||
```
|
||||
|
||||
你可以把 `$GOPATH` 下的 `bin` 目录添加到 `$PATH` 中。这样你就可以像使用系统上的其他命令一样来使用 gosec 命令行工具（CLI）了。
|
||||
|
||||
你可以把 `$GOPATH` 下的 `bin` 目录添加到 `$PATH` 中。这样你就可以像使用系统上的其他命令一样来使用 `gosec` 命令行工具（CLI）了。
|
||||
|
||||
```
|
||||
$ which gosec
|
||||
@ -89,8 +78,7 @@ $ which gosec
|
||||
$
|
||||
```
|
||||
|
||||
使用 gosec 命令行工具的 `-help` 选项来看看运行是否符合预期：
|
||||
|
||||
使用 `gosec` 命令行工具的 `-help` 选项来看看运行是否符合预期：
|
||||
|
||||
```
|
||||
$ gosec -help
|
||||
@ -109,17 +97,12 @@ USAGE:
|
||||
|
||||
之后，创建一个目录，把源码下载到这个目录作为实例项目（本例中，我用的是 Docker CE）：
|
||||
|
||||
|
||||
```
|
||||
$ mkdir gosec-demo
|
||||
$
|
||||
$ cd gosec-demo/
|
||||
$
|
||||
$ pwd
|
||||
/root/gosec-demo
|
||||
$
|
||||
|
||||
$ git clone <https://github.com/docker/docker-ce.git>
|
||||
$ git clone https://github.com/docker/docker-ce.git
|
||||
Cloning into 'docker-ce'...
|
||||
remote: Enumerating objects: 1271, done.
|
||||
remote: Counting objects: 100% (1271/1271), done.
|
||||
@ -128,10 +111,9 @@ remote: Total 431003 (delta 384), reused 981 (delta 318), pack-reused 429732
|
||||
Receiving objects: 100% (431003/431003), 166.84 MiB | 28.94 MiB/s, done.
|
||||
Resolving deltas: 100% (221338/221338), done.
|
||||
Updating files: 100% (10861/10861), done.
|
||||
$
|
||||
```
|
||||
|
||||
代码统计工具（本例中用的是 cloc）显示这个项目大部分是用 Go 写的，恰好迎合了 gosec 的功能。
|
||||
代码统计工具（本例中用的是 `cloc`）显示这个项目大部分是用 Go 写的，恰好迎合了 `gosec` 的功能。
|
||||
|
||||
|
||||
```
|
||||
@ -140,9 +122,10 @@ $ ./cloc /root/gosec-demo/docker-ce/
|
||||
8724 unique files.
|
||||
2560 files ignored.
|
||||
|
||||
\-----------------------------------------------------------------------------------
|
||||
|
||||
-----------------------------------------------------------------------------------
|
||||
Language files blank comment code
|
||||
\-----------------------------------------------------------------------------------
|
||||
-----------------------------------------------------------------------------------
|
||||
Go 7222 190785 230478 1574580
|
||||
YAML 37 4831 817 156762
|
||||
Markdown 529 21422 0 67893
|
||||
@ -151,13 +134,11 @@ Protocol Buffers 149 5014 16562 10
|
||||
|
||||
### 使用默认选项运行 gosec
|
||||
|
||||
在 Docker CE 项目中使用默认选项运行 gosec，执行 `gosec ./...` 命令。屏幕上会有很多输出内容。在末尾你会看到一个简短的 `Summary`，列出了浏览的文件数、所有文件的总行数，以及源码中发现的问题数。
|
||||
|
||||
在 Docker CE 项目中使用默认选项运行 `gosec`，执行 `gosec ./...` 命令。屏幕上会有很多输出内容。在末尾你会看到一个简短的 “Summary”，列出了浏览的文件数、所有文件的总行数，以及源码中发现的问题数。
|
||||
|
||||
```
|
||||
$ pwd
|
||||
/root/gosec-demo/docker-ce
|
||||
$
|
||||
$ time gosec ./...
|
||||
[gosec] 2020/08/20 04:44:15 Including rules: default
|
||||
[gosec] 2020/08/20 04:44:15 Excluding rules: default
|
||||
@ -183,180 +164,166 @@ $
|
||||
|
||||
滚动屏幕你会看到不同颜色高亮的行：红色表示需要尽快查看的高优先级问题，黄色表示中优先级的问题。
|
||||
|
||||
#### 关于“假阳性”
|
||||
#### 关于误判
|
||||
|
||||
在开始检查代码之前，我想先分享几条基本原则。默认情况下，静态检查工具会基于一系列的规则对测试代码进行分析并报告出检查出来的*所有*问题。这表示工具报出来的每一个问题都需要修复吗？非也。这个问题最好的解答者是设计和开发这个软件的人。他们最熟悉代码，更重要的是，他们了解软件会在什么环境下部署以及会被怎样使用。
|
||||
在开始检查代码之前，我想先分享几条基本原则。默认情况下，静态检查工具会基于一系列的规则对测试代码进行分析，并报告出它们发现的*所有*问题。这是否意味着工具报出来的每一个问题都需要修复？非也。这个问题最好的解答者是设计和开发这个软件的人。他们最熟悉代码，更重要的是，他们了解软件会在什么环境下部署以及会被怎样使用。
|
||||
|
||||
这个知识点对于判定工具标记出来的某段代码到底是不是安全缺陷至关重要。随着工作时间和经验的积累，你会慢慢学会怎样让静态分析工具忽略非安全缺陷，使报告内容的可执行性更高。因此，要判定 gosec 报出来的某个问题是否需要修复，让一名有经验的开发者对源码做人工审计会是比较好的办法。
|
||||
这个知识点对于判定工具标记出来的某段代码到底是不是安全缺陷至关重要。随着工作时间和经验的积累，你会慢慢学会怎样让静态分析工具忽略非安全缺陷，使报告内容的可执行性更高。因此，要判定 `gosec` 报出来的某个问题是否需要修复，让一名有经验的开发者对源码做人工审计会是比较好的办法。
|
||||
|
||||
#### 高优先级问题
|
||||
|
||||
从输出内容看，gosec 发现了 Docker CE 的一个高优先级问题，它使用的是低版本的 TLS（<ruby>传输层安全<rt>Transport Layer Security<rt></ruby>）。无论什么时候，使用软件和库的最新版本都是确保它更新及时、没有安全问题的最好的方法。
|
||||
|
||||
从输出内容看，`gosec` 发现了 Docker CE 的一个高优先级问题，它使用的是低版本的 TLS（<ruby>传输层安全<rt>Transport Layer Security<rt></ruby>）。无论什么时候，使用软件和库的最新版本都是确保它更新及时、没有安全问题的最好的方法。
|
||||
|
||||
```
|
||||
[/root/gosec-demo/docker-ce/components/engine/daemon/logger/splunk/splunk.go:173] - G402 (CWE-295): TLS MinVersion too low. (Confidence: HIGH, Severity: HIGH)
|
||||
172:
|
||||
> 173: tlsConfig := &tls.Config{}
|
||||
> 173: tlsConfig := &tls.Config{}
|
||||
174:
|
||||
```
|
||||
|
||||
它还发现了一个伪随机数生成器。它是不是一个安全缺陷，取决于生成的随机数的使用方式。
|
||||
|
||||
它还发现了一个弱随机数生成器。它是不是一个安全缺陷，取决于生成的随机数的使用方式。
|
||||
|
||||
```
|
||||
[/root/gosec-demo/docker-ce/components/engine/pkg/namesgenerator/names-generator.go:843] - G404 (CWE-338): Use of weak random number generator (math/rand instead of crypto/rand) (Confidence: MEDIUM, Severity: HIGH)
|
||||
842: begin:
|
||||
> 843: name := fmt.Sprintf("%s_%s", left[rand.Intn(len(left))], right[rand.Intn(len(right))])
|
||||
> 843: name := fmt.Sprintf("%s_%s", left[rand.Intn(len(left))], right[rand.Intn(len(right))])
|
||||
844: if name == "boring_wozniak" /* Steve Wozniak is not boring */ {
|
||||
```
|
||||
|
||||
#### 中优先级问题
|
||||
|
||||
这个工具还发现了一些中优先级问题。它标记了一个通过与 tar 相关的解压炸弹这种方式实现的潜在的 DoS 威胁，这种方式可能会被恶意的攻击者利用。
|
||||
|
||||
这个工具还发现了一些中优先级问题。它标记了一个通过与 `tar` 相关的解压炸弹这种方式实现的潜在的 DoS 威胁，这种方式可能会被恶意的攻击者利用。
|
||||
|
||||
```
|
||||
[/root/gosec-demo/docker-ce/components/engine/pkg/archive/copy.go:357] - G110 (CWE-409): Potential DoS vulnerability via decompression bomb (Confidence: MEDIUM, Severity: MEDIUM)
|
||||
356:
|
||||
> 357: if _, err = io.Copy(rebasedTar, srcTar); err != nil {
|
||||
> 357: if _, err = io.Copy(rebasedTar, srcTar); err != nil {
|
||||
358: w.CloseWithError(err)
|
||||
```
|
||||
|
||||
它还发现了一个通过变量访问文件的问题。如果恶意使用者能访问这个变量，那么他们就可以改变变量的值去读其他文件。
|
||||
|
||||
|
||||
```
|
||||
[/root/gosec-demo/docker-ce/components/cli/cli/context/tlsdata.go:80] - G304 (CWE-22): Potential file inclusion via variable (Confidence: HIGH, Severity: MEDIUM)
|
||||
79: if caPath != "" {
|
||||
> 80: if ca, err = ioutil.ReadFile(caPath); err != nil {
|
||||
> 80: if ca, err = ioutil.ReadFile(caPath); err != nil {
|
||||
81: return nil, err
|
||||
```
|
||||
|
||||
文件和目录通常是操作系统安全的最基础的元素。这里，gosec 报出了一个可能需要你检查目录的权限是否安全的问题。
|
||||
|
||||
文件和目录通常是操作系统安全的最基础的元素。这里，`gosec` 报出了一个可能需要你检查目录的权限是否安全的问题。
|
||||
|
||||
```
|
||||
[/root/gosec-demo/docker-ce/components/engine/contrib/apparmor/main.go:41] - G301 (CWE-276): Expect directory permissions to be 0750 or less (Confidence: HIGH, Severity: MEDIUM)
|
||||
40: // make sure /etc/apparmor.d exists
|
||||
> 41: if err := os.MkdirAll(path.Dir(apparmorProfilePath), 0755); err != nil {
|
||||
> 41: if err := os.MkdirAll(path.Dir(apparmorProfilePath), 0755); err != nil {
|
||||
42: log.Fatal(err)
|
||||
```
|
||||
|
||||
你经常需要在源码中启动命令行工具。Go 使用内建的 exec 库来实现。仔细地分析用来调用这些工具的变量，就能发现安全缺陷。
|
||||
|
||||
|
||||
```
|
||||
[/root/gosec-demo/docker-ce/components/engine/testutil/fakestorage/fixtures.go:59] - G204 (CWE-78): Subprocess launched with variable (Confidence: HIGH, Severity: MEDIUM)
|
||||
58:
|
||||
> 59: cmd := exec.Command(goCmd, "build", "-o", filepath.Join(tmp, "httpserver"), "github.com/docker/docker/contrib/httpserver")
|
||||
> 59: cmd := exec.Command(goCmd, "build", "-o", filepath.Join(tmp, "httpserver"), "github.com/docker/docker/contrib/httpserver")
|
||||
60: cmd.Env = append(os.Environ(), []string{
|
||||
```
|
||||
|
||||
#### 低优先级问题
|
||||
|
||||
在这个输出中，gosec 报出了一个 “unsafe” 调用相关的低优先级问题，这个调用会绕开 Go 提供的内存保护。再仔细分析下你调用 “unsafe” 的方式，看看是否有被别人利用的可能性。
|
||||
|
||||
在这个输出中，gosec 报出了一个 `unsafe` 调用相关的低优先级问题，这个调用会绕开 Go 提供的内存保护。再仔细分析下你调用 `unsafe` 的方式，看看是否有被别人利用的可能性。
|
||||
|
||||
```
|
||||
[/root/gosec-demo/docker-ce/components/engine/pkg/archive/changes_linux.go:264] - G103 (CWE-242): Use of unsafe calls should be audited (Confidence: HIGH, Severity: LOW)
|
||||
263: for len(buf) > 0 {
|
||||
> 264: dirent := (*unix.Dirent)(unsafe.Pointer(&buf[0]))
|
||||
263: for len(buf) > 0 {
|
||||
> 264: dirent := (*unix.Dirent)(unsafe.Pointer(&buf[0]))
|
||||
265: buf = buf[dirent.Reclen:]
|
||||
|
||||
|
||||
|
||||
[/root/gosec-demo/docker-ce/components/engine/pkg/devicemapper/devmapper_wrapper.go:88] - G103 (CWE-242): Use of unsafe calls should be audited (Confidence: HIGH, Severity: LOW)
|
||||
87: func free(p *C.char) {
|
||||
> 88: C.free(unsafe.Pointer(p))
|
||||
> 88: C.free(unsafe.Pointer(p))
|
||||
89: }
|
||||
```
|
||||
|
||||
它还标记了源码中未处理的错误。源码中出现的错误你都应该处理。
|
||||
|
||||
|
||||
```
|
||||
[/root/gosec-demo/docker-ce/components/cli/cli/command/image/build/context.go:172] - G104 (CWE-703): Errors unhandled. (Confidence: HIGH, Severity: LOW)
|
||||
171: err := tar.Close()
|
||||
> 172: os.RemoveAll(dockerfileDir)
|
||||
> 172: os.RemoveAll(dockerfileDir)
|
||||
173: return err
|
||||
```
|
||||
|
||||
### 自定义 gosec 扫描
|
||||
|
||||
使用 gosec 的默认选项带来了很多的问题。然而，经过人工审计和随着时间推移，你会掌握哪些问题是不需要标记的。你可以自己指定排除和包含哪些测试。
|
||||
使用 `gosec` 的默认选项会带来很多的问题。然而，经过人工审计，随着时间推移你会掌握哪些问题是不需要标记的。你可以自己指定排除和包含哪些测试。
|
||||
|
||||
我上面提到过，gosec 是基于一系列的规则从 Go 源码中查找问题的。下面是它使用的完整的[规则][10]列表：
|
||||
|
||||
* G101：查找硬编码凭证
|
||||
我上面提到过，`gosec` 是基于一系列的规则从 Go 源码中查找问题的。下面是它使用的完整的[规则][10]列表：
|
||||
|
||||
- G101：查找硬编码凭证
|
||||
- G102：绑定到所有接口
|
||||
- G103：审计不安全区块的使用
|
||||
- G103：审计 `unsafe` 块的使用
|
||||
- G104：审计未检查的错误
|
||||
- G106：审计 ssh.InsecureIgnoreHostKey 的使用
|
||||
- G107: 提供给 HTTP 请求的 url 作为污点输入
|
||||
- G108: 统计端点自动暴露到 /debug/pprof
|
||||
- G109: strconv.Atoi 转换到 int16 或 int32 时潜在的整数溢出
|
||||
- G110: 潜在的通过解压炸弹实现的 DoS
|
||||
- G106：审计 `ssh.InsecureIgnoreHostKey` 的使用
|
||||
- G107: 提供给 HTTP 请求的 url 作为污点输入
|
||||
- G108: `/debug/pprof` 上自动暴露的剖析端点
|
||||
- G109: `strconv.Atoi` 转换到 int16 或 int32 时潜在的整数溢出
|
||||
- G110: 潜在的通过解压炸弹实现的 DoS
|
||||
- G201：SQL 查询构造使用格式字符串
|
||||
- G202：SQL 查询构造使用字符串连接
|
||||
- G203：在 HTML 模板中使用未转义的数据
|
||||
- G203：在HTML模板中使用未转义的数据
|
||||
- G204：审计命令执行情况
|
||||
- G301：创建目录时文件权限分配不合理
|
||||
- G302：chmod 文件权限分配不合理
|
||||
- G302：使用 `chmod` 时文件权限分配不合理
|
||||
- G303：使用可预测的路径创建临时文件
|
||||
- G304：作为污点输入提供的文件路径
|
||||
- G304：通过污点输入提供的文件路径
|
||||
- G305：提取 zip/tar 文档时遍历文件
|
||||
- G306: 写到新文件时文件权限分配不合理
|
||||
- G307: 把返回错误的函数放到 defer 内
|
||||
- G401：检测 DES、RC4、MD5 或 SHA1 的使用情况
|
||||
- G306: 写到新文件时文件权限分配不合理
|
||||
- G307: 把返回错误的函数放到 `defer` 内
|
||||
- G401：检测 DES、RC4、MD5 或 SHA1 的使用
|
||||
- G402：查找错误的 TLS 连接设置
|
||||
- G403：确保最小 RSA 密钥长度为 2048 位
|
||||
- G404：不安全的随机数源（rand）
|
||||
- G404：不安全的随机数源（`rand`）
|
||||
- G501：导入黑名单列表：crypto/md5
|
||||
- G502：导入黑名单列表：crypto/des
|
||||
- G503：导入黑名单列表：crypto/rc4
|
||||
- G504：导入黑名单列表：net/http/cgi
|
||||
- G505：导入黑名单列表：crypto/sha1
|
||||
- G601: 在 range 语句中使用隐式的元素别名
|
||||
|
||||
|
||||
- G601: 在 `range` 语句中使用隐式的元素别名
|
||||
|
||||
#### 排除指定的测试
|
||||
|
||||
你可以自定义 gosec 来避免对已知为安全的问题进行扫描和报告。你可以使用 `-exclude` 选项和上面的规则编号来忽略指定的问题。
|
||||
|
||||
例如，如果你不想让 gosec 检查源码中硬编码凭证相关的未处理的错误，那么你可以运行下面的命令来忽略这些错误：
|
||||
你可以自定义 `gosec` 来避免对已知为安全的问题进行扫描和报告。你可以使用 `-exclude` 选项和上面的规则编号来忽略指定的问题。
|
||||
|
||||
例如，如果你不想让 `gosec` 检查源码中硬编码凭证相关的未处理的错误，那么你可以运行下面的命令来忽略这些错误：
|
||||
|
||||
```
|
||||
$ gosec -exclude=G104 ./...
|
||||
$ gosec -exclude=G104,G101 ./...
|
||||
```
|
||||
|
||||
有时候你知道某段代码是安全的，但是 gosec 还是会报出问题。然而，你又不想完全排除掉整个检查，因为你想让 gosec 检查新增的代码。通过在你已知为安全的代码块添加 `#nosec` 标记可以避免 gosec 扫描。这样 gosec 会继续扫描新增代码，而忽略掉 `#nosec` 标记的代码块。
|
||||
有时候你知道某段代码是安全的，但是 `gosec` 还是会报出问题。然而，你又不想完全排除掉整个检查，因为你想让 `gosec` 检查新增的代码。通过在你已知为安全的代码块添加 `#nosec` 标记可以避免 `gosec` 扫描。这样 `gosec` 会继续扫描新增代码，而忽略掉 `#nosec` 标记的代码块。
|
||||
|
||||
#### 运行指定的检查
|
||||
|
||||
另一方面，如果你只想检查指定的问题，你可以通过 `-include` 选项和规则编号来告诉 gosec 运行哪些检查：
|
||||
|
||||
另一方面，如果你只想检查指定的问题，你可以通过 `-include` 选项和规则编号来告诉 `gosec` 运行哪些检查：
|
||||
|
||||
```
|
||||
`$ gosec -include=G201,G202 ./...`
|
||||
$ gosec -include=G201,G202 ./...
|
||||
```
|
||||
|
||||
#### 扫描测试文件
|
||||
|
||||
Go 语言自带对测试的支持，通过单元测试来检验一个元素是否符合预期。在默认模式下，gosec 会忽略测试文件，你可以使用 `-tests` 选项把它们包含进来：
|
||||
|
||||
Go 语言自带对测试的支持，通过单元测试来检验一个元素是否符合预期。在默认模式下，`gosec` 会忽略测试文件，你可以使用 `-tests` 选项把它们包含进来：
|
||||
|
||||
```
|
||||
`gosec -tests ./...`
|
||||
gosec -tests ./...
|
||||
```
|
||||
|
||||
#### 修改输出的格式
|
||||
|
||||
找出问题只是它的一半功能；另一半功能是把它检查到的问题以用户友好同时又方便工具处理的方式报告出来。幸运的是，gosec 可以用不同的方式输出。例如，如果你想看 JSON 格式的报告，那么就使用 `-fmt` 选项指定 JSON 格式并把结果保存到 `results.json` 文件中：
|
||||
|
||||
找出问题只是它的一半功能；另一半功能是把它检查到的问题以用户友好同时又方便工具处理的方式报告出来。幸运的是，`gosec` 可以用不同的方式输出。例如，如果你想看 JSON 格式的报告，那么就使用 `-fmt` 选项指定 JSON 格式并把结果保存到 `results.json` 文件中：
|
||||
|
||||
```
|
||||
$ gosec -fmt=json -out=results.json ./...
|
||||
@ -370,7 +337,7 @@ $
|
||||
"confidence": "HIGH",
|
||||
"cwe": {
|
||||
"ID": "242",
|
||||
"URL": "<https://cwe.mitre.org/data/definitions/242.html>"
|
||||
"URL": "https://cwe.mitre.org/data/definitions/242.html"
|
||||
},
|
||||
"rule_id": "G103",
|
||||
"details": "Use of unsafe calls should be audited",
|
||||
@ -381,9 +348,9 @@ $
|
||||
},
|
||||
```
|
||||
|
||||
### 用 gosec 检查容易暴露出来的问题
|
||||
### 用 gosec 检查容易被发现的问题
|
||||
|
||||
静态检查工具不能完全代替人工代码审计。然而，当代码量变大、有众多开发者时，这样的工具通常能用批量的方式帮忙找出容易暴露的问题。它对于帮助新开发者识别和在编码时避免引入这些安全缺陷很有用。
|
||||
静态检查工具不能完全代替人工代码审计。然而，当代码量变大、有众多开发者时，这样的工具往往有助于以可重复的方式找出容易被发现的问题。它对于帮助新开发者识别和在编码时避免引入这些安全缺陷很有用。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
@ -392,7 +359,7 @@ via: https://opensource.com/article/20/9/gosec
|
||||
作者：[Gaurav Kamathe][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[lxbowlf](https://github.com/lxbwolf)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
@ -1,52 +1,52 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (geekpi)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: reviewer: (wxy)
|
||||
[#]: publisher: (wxy)
|
||||
[#]: url: (https://linux.cn/article-12691-1.html)
|
||||
[#]: subject: (5 questions to ask yourself when writing project documentation)
|
||||
[#]: via: (https://opensource.com/article/20/9/project-documentation)
|
||||
[#]: author: (Alexei Leontief https://opensource.com/users/alexeileontief)
|
||||
|
||||
编写项目文档时要问自己 5 个问题
|
||||
编写项目文档时要问自己的 5 个问题
|
||||
======
|
||||
使用一些有效沟通的基本原则可以帮助你创建与你的品牌一致的，编写良好，内容丰富的项目文档。
|
||||
![A person writing.][1]
|
||||
|
||||
在开始另一个开源项目文档的实际写作部分之前，甚至在采访专家之前，最好回答一些有关新文档的高级问题。
|
||||
> 使用有效沟通的一些基本原则可以帮助你创建与你的品牌一致的、编写良好、内容丰富的项目文档。
|
||||
|
||||
著名的传播理论家 Harold Lasswell 在他 1948 年的文章《社会中的传播结构和功能》（_The Structure and Function of Communication in Society_）中写道：
|
||||
|
||||
|
||||
> （一个）描述沟通行为的方便方法是回答以下问题：
|
||||
在开始实际撰写又一个开源项目的文档之前，甚至在采访专家之前，最好回答一些有关新文档的高级问题。
|
||||
|
||||
著名的传播理论家 Harold Lasswell 在他 1948 年的文章《<ruby>社会中的传播结构和功能<rt>The Structure and Function of Communication in Society</rt></ruby>》中写道：
|
||||
|
||||
> （一种）描述沟通行为的方便方法是回答以下问题：
|
||||
>
|
||||
> * 谁
|
||||
> * 说什么
|
||||
> * 在哪个渠道
|
||||
> * 对谁
|
||||
> * 有什么效果？
|
||||
>
|
||||
|
||||
作为一名技术交流者，你可以运用 Lasswell 的理论，回答关于你文档的类似问题，以更好地传达你的信息，达到预期的效果。
|
||||
|
||||
作为一名技术沟通者，你可以运用 Lasswell 的理论，回答关于你文档的类似问题，以更好地传达你的信息，达到预期的效果。
|
||||
### 谁：谁是文档的所有者？
|
||||
|
||||
### 谁—谁是文档的所有者？
|
||||
或者说，文档背后是什么公司？它想向受众传达什么品牌形象？这个问题的答案将极大地影响你的写作风格。公司可能有自己的风格指南，或者至少有正式的使命声明，在这种情况下，你应该从这开始。
|
||||
|
||||
或者说，文档背后是什么公司？它想向受众传达什么品牌形象？这个问题的答案将大大影响你的写作风格。公司也可能有自己的风格指南，或者至少有正式的使命声明，在这种情况下，你应该从这开始。
|
||||
如果公司刚刚起步，你可以向文件的主人提出上述问题。作为作者，将你为公司创造的声音和角色与你自己的世界观和信念结合起来是很重要的。这将使你的写作看起来更自然，而不像公司的行话。
|
||||
|
||||
如果公司刚刚起步，你可以向文件的主人提出上述问题。作为作者，将你为公司创造的声音和角色与你自己的世界观和信仰结合起来是很重要的。这将使你的写作看起来更自然，而不像公司的行话。
|
||||
### 说什么：文件类型是什么？
|
||||
|
||||
### 说什么—文件类型是什么？
|
||||
你需要传达什么信息？它是什么类型的文档：用户指南、API 参考、发布说明等？许多文档类型有模板或普遍认可的结构，这些结构为你提供一个开始的地方，并帮助确保包括所有必要的信息。
|
||||
|
||||
你需要传达什么信息？它是什么类型的文档：用户指南、API 参考、发布说明等？许多文档类型将有模板或普遍认可的结构，它将让你从这开始，并帮助确保包括所有必要的信息。
|
||||
|
||||
### 在哪个渠道—文档的格式是什么？
|
||||
### 在哪个渠道：文档的格式是什么？
|
||||
|
||||
对于技术文档，沟通的渠道通常会告诉你文档的最终格式，也就是 PDF、HTML、文本文件等。这很可能也决定了你应该使用什么工具来编写你的文档。
|
||||
|
||||
### 对谁—目标受众是谁？
|
||||
### 对谁：目标受众是谁？
|
||||
|
||||
谁会阅读这份文档？他们的知识水平如何？他们的工作职责和主要挑战是什么？这些问题将帮助你确定你应该覆盖什么，是否应该进入细节，是否可以使用任何特定的术语，等等。在某些情况下，这些问题的答案甚至可以影响你使用的语法的复杂性。
|
||||
谁会阅读这份文档？他们的知识水平如何？他们的工作职责和主要挑战是什么？这些问题将帮助你确定你应该覆盖什么内容，是否应该应该涉及细节，是否可以使用特定的术语，等等。在某些情况下，这些问题的答案甚至可以影响你使用的语法的复杂性。
|
||||
|
||||
### 有什么效果-文档的目的是什么？
|
||||
### 有什么效果：文档的目的是什么？
|
||||
|
||||
在这里，你应该定义这个文档要为它的潜在读者解决什么问题，或者它应该为他们回答什么问题。例如，你的文档的目的可以是教你的客户如何使用你的产品。
|
||||
|
||||
@ -56,7 +56,7 @@
|
||||
|
||||
### 总结
|
||||
|
||||
上面的问题旨在帮助你形成有效沟通的基础，并确保你的文件涵盖了所有应该涵盖的内容。你可以把它们分解成你自己的问题清单，并把它们放在身边，以便在你有文件要创建的时候使用。当你面对空白页时，这份清单也可能会派上用场。希望它能激发你的灵感，帮助你产生想法。
|
||||
上面的问题旨在帮助你形成有效沟通的基础，并确保你的文件涵盖了所有应该涵盖的内容。你可以把它们分解成你自己的问题清单，并把它们放在身边，以便在你有文件要创建的时候使用。当你面对空白页无从着笔时，这份清单也可能会派上用场。希望它能激发你的灵感，帮助你产生想法。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
@ -65,7 +65,7 @@ via: https://opensource.com/article/20/9/project-documentation
|
||||
作者：[Alexei Leontief][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[geekpi](https://github.com/geekpi)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
@ -1,8 +1,8 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (rakino)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: reviewer: (wxy)
|
||||
[#]: publisher: (wxy)
|
||||
[#]: url: (https://linux.cn/article-12699-1.html)
|
||||
[#]: subject: (Create template files in GNOME)
|
||||
[#]: via: (https://opensource.com/article/20/9/gnome-templates)
|
||||
[#]: author: (Alan Formy-Duval https://opensource.com/users/alanfdoss)
|
||||
@ -10,27 +10,23 @@
|
||||
在 GNOME 中创建文档模板
|
||||
======
|
||||
|
||||
![Digital images of a computer desktop][1]
|
||||
> 制作模板可以让你更快地开始写作新的文档。
|
||||
|
||||
制作模板可以让你更快地开始写作新的文档。
|
||||
|
||||
|
||||
我偶然发现了 [GNOME][2] 的一个新功能（对我来说是的）：创建文档模版。模版（template）也被称作样版文件（boilerplate），一般是有着特定格式的空文档，例如律师事务所的信笺，在其顶部有着律所的名称和地址；另一个例子是银行以及保险公司的保函，在其底部页脚包含着某些免责声明。由于这类信息很少改变，你可以把它们添加到空文档中作为模板使用。
|
||||
我只是偶然发现了 [GNOME][2] 的一个新功能（对我来说是的）：创建文档模版。<ruby>模版<rt>template</rt></ruby>也被称作<ruby>样版文件<rt>boilerplate</rt></ruby>，一般是有着特定格式的空文档，例如律师事务所的信笺，在其顶部有着律所的名称和地址；另一个例子是银行以及保险公司的保函，在其底部页脚包含着某些免责声明。由于这类信息很少改变，你可以把它们添加到空文档中作为模板使用。
|
||||
|
||||
一天，在浏览我的 Linux 系统文件的时候，我点击了**模板**（Templates）文件夹，然后刚好发现窗口的上方有一条消息写着：“将文件放入此文件夹并用作新文档的模板”，以及一个**获取详情……** 的链接，指向了 [GNOME 指南（GNOME help）][3]中的模板页面。
|
||||
一天，在浏览我的 Linux 系统文件的时候，我点击了<ruby>模板<rt>Templates</rt></ruby>文件夹，然后刚好发现窗口的上方有一条消息写着：“将文件放入此文件夹并用作新文档的模板”，以及一个“获取详情……” 的链接，打开了模板的 [GNOME 帮助页面][3]。
|
||||
|
||||
![Message at top of Templates folder in GNOME Desktop][4]
|
||||
|
||||
(Alan Formy-Duval, [CC BY-SA 4.0][5])
|
||||
|
||||
### 创建模板
|
||||
|
||||
在 GNOME 中创建模板非常简单。有几种方法可以把文件放进模板文件夹里：你既可以通过图形用户界面（GUI）或是命令行界面（CLI）从另一个位置复制或移动文件，也可以创建一个全新的文件；我选择了后者，实际上我也创建了两个文件。
|
||||
在 GNOME 中创建模板非常简单。有几种方法可以把文件放进模板文件夹里：你既可以通过图形用户界面（GUI）或是命令行界面（CLI）从另一个位置复制或移动文件，也可以创建一个全新的文件；我选择了后者，实际上，我创建了两个文件。
|
||||
|
||||
![My first two GNOME templates][6]
|
||||
|
||||
(Alan Formy-Duval, [CC BY-SA 4.0][5])
|
||||
|
||||
我的第一份模板是为 Opensource.com 的文章准备的，它有一个输入标题的位置以及关于我的名字和文章使用的许可证的几行。我的文章使用 Markdown 格式，所以我将模板创建为了一个新的 Markdown 文档——**Opensource.com Article.md**：
|
||||
我的第一份模板是为 Opensource.com 的文章准备的，它有一个输入标题的位置以及关于我的名字和文章使用的许可证的几行。我的文章使用 Markdown 格式，所以我将模板创建为了一个新的 Markdown 文档——`Opensource.com Article.md`：
|
||||
|
||||
````
|
||||
# Title
|
||||
@ -46,12 +42,10 @@ Creative Commons BY-SA 4.0
|
||||
|
||||
### 使用模板
|
||||
|
||||
每当我有了新文章的灵感的时候，我只需要在我计划用来组织内容的文件夹里单击右键，然后从**新建文档**（New Document）列表中选择我想要的模板就可以开始了。
|
||||
每当我有了新文章的灵感的时候，我只需要在我计划用来组织内容的文件夹里单击右键，然后从<ruby>新建文档<rt>New Document</rt></ruby>列表中选择我想要的模板就可以开始了。
|
||||
|
||||
![Select the template by name][7]
|
||||
|
||||
(Alan Formy-Duval, [CC BY-SA 4.0][5])
|
||||
|
||||
你可以为各种文档或文件制作模板。我写这篇文章时使用了我为 Opensource.com 的文章创建的模板。程序员可能会把模板用于软件代码，这样的话也许你想要只包含 `main()` 的模板。
|
||||
|
||||
GNOME 桌面环境为 Linux 及相关操作系统的用户提供了一个非常实用、功能丰富的界面。你最喜欢的 GNOME 功能是什么，你又是怎样使用它们的呢？请在评论中分享～
|
||||
@ -63,7 +57,7 @@ via: https://opensource.com/article/20/9/gnome-templates
|
||||
作者：[Alan Formy-Duval][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[rakino](https://github.com/rakino)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
@ -1,22 +1,24 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: translator: (rakino)
|
||||
[#]: reviewer: (wxy)
|
||||
[#]: publisher: (wxy)
|
||||
[#]: url: (https://linux.cn/article-12702-1.html)
|
||||
[#]: subject: (How to view information on your Linux devices with lshw)
|
||||
[#]: via: (https://www.networkworld.com/article/3583598/how-to-view-information-on-your-linux-devices-with-lshw.html)
|
||||
[#]: author: (Sandra Henry-Stocker https://www.networkworld.com/author/Sandra-Henry_Stocker/)
|
||||
|
||||
How to view information on your Linux devices with lshw
|
||||
如何使用 lshw 查看 Linux 设备信息
|
||||
======
|
||||
The lshw (list hardware) command on Linux systems provides a lot more information on system devices than most of us might imagine is available.
|
||||
Kali Linux / nevarpp / Getty Images
|
||||
|
||||
While far from being one of the first 50 Linux commands anyone learns, the **lshw** command (read as “ls hardware”) can provide a lot of useful details on your system’s hardware.
|
||||
> Linux 系统上的 lshw 命令提供的系统设备信息比我们大多数人想象的要多得多。
|
||||
|
||||
It extracts details—maybe quite a few more than you knew were available—in a format that is reasonably easy to digest. Given descriptions, logical (device) names, sizes, etc., you are likely to appreciate how much detail you can access.
|
||||
![Kali Linux logo / gears / binary data][1]
|
||||
|
||||
This post examines the information that **lshw** provides with a particular focus on disk and related hardware. Here is some sample **lshw** output:
|
||||
虽然 `lshw` 命令（<ruby>列出硬件<rt>list hardware</rt></ruby>，读作 “ls hardware”）远不是每个人最先学会的 50 个 Linux 命令之一，但它可以提供很多系统硬件的有用信息。
|
||||
|
||||
它以一种相当易于理解的格式提取出可能比你知道的更多的信息。在看到描述、（设备）逻辑名称、大小等以后，你可能会理解到自己能获得多少信息。
|
||||
|
||||
这篇文章会研究 `lshw` 给出的信息，但侧重于磁盘及相关硬件。下面是 `lshw` 的输出示例：
|
||||
|
||||
```
|
||||
$ sudo lshw -C disk
|
||||
@ -35,11 +37,11 @@ $ sudo lshw -C disk
|
||||
logical name: /dev/sdc
|
||||
```
|
||||
|
||||
Note that you should run the **lshw** command with **sudo** to ensure that you get all of the available details.
|
||||
请注意，你需要使用 `sudo` 运行 `lshw` 命令以确保能得到所有可用的信息。
|
||||
|
||||
While we asked for “disk” in the above command (the output included shows only the first of five entries displayed), this particular output shows not a hard disk, but a card reader—another member of the disk class. Note that the system knows this device as **/dev/sdc**.
|
||||
虽然我们在上面的命令中要求了输出“磁盘（`disk`）”（上面只包含了原始输出里五个条目中的一个），这里的输出却不是一个硬盘，而是读卡器——磁盘的一种。注意系统将这个设备命名为了 `/dev/sdc`。
|
||||
|
||||
Similar details are provided on the primary disk on the system:
|
||||
系统的主磁盘上也有相似的信息：
|
||||
|
||||
```
|
||||
*-disk
|
||||
@ -47,7 +49,7 @@ Similar details are provided on the primary disk on the system:
|
||||
product: SSD2SC120G1CS175
|
||||
physical id: 0
|
||||
bus info: scsi@0:0.0.0
|
||||
logical name: /dev/sda <==
|
||||
logical name: /dev/sda <==这里
|
||||
version: 1101
|
||||
serial: PNY20150000778410606
|
||||
size: 111GiB (120GB)
|
||||
@ -56,9 +58,9 @@ Similar details are provided on the primary disk on the system:
|
||||
f63b5929
|
||||
```
|
||||
|
||||
This disk is **/dev/sda**. The hard disks on this system both show up as **ATA** disks. **ATA** is a disk-drive implementation that integrates the controller on the disk drive itself.
|
||||
这块硬盘是 `/dev/sda`。这个系统上的硬盘都显示为 `ATA` 磁盘，`ATA` 是一种把控制器与盘体集成在一起的磁盘驱动器实现。
|
||||
|
||||
To get an abbreviated list of devices in the “disk” class, you can run a command like this one. Notice that two of the devices are listed twice, so we are still seeing five disk devices.
|
||||
要获得“磁盘”类设备的简略列表，可以运行下面这条命令。注意其中有两个设备被列出了两次，所以我们看到的仍然是五个磁盘设备。
|
||||
|
||||
```
|
||||
$ sudo lshw -short -C disk
|
||||
@ -73,7 +75,7 @@ H/W path Device Class Description
|
||||
/0/100/1f.5/0.0.0 /dev/sdb disk 500GB SAMSUNG HE502HJ
|
||||
```
|
||||
|
||||
Hold onto your seat if you decide you want to see _**all**_ of the devices on a system. You will get a list that includes a lot more things than you probably normally think of as “devices”. Here’s an example—and this is the “short” (few details) list:
|
||||
如果你决定要查看系统上的 **所有** 设备，请坐稳了；你会得到一个包含的东西比你通常认为的“设备”要多得多的列表，下面是一个例子，这是一个“简短（`short`）”（信息很少）的列表：
|
||||
|
||||
```
|
||||
$ sudo lshw -short
|
||||
@ -152,7 +154,7 @@ H/W path Device Class Description
|
||||
/0/9 system PnP device PNP0c01
|
||||
```
|
||||
|
||||
Run a command like this to list device classes and count how many devices are in each class.
|
||||
运行下面的命令来列出设备类别，并统计每个类别中的设备数量。
|
||||
|
||||
```
|
||||
$ sudo lshw -short | awk ‘{print substr($0,36,13)}’ | tail -n +3 | sort | uniq -c
|
||||
@ -172,16 +174,18 @@ $ sudo lshw -short | awk ‘{print substr($0,36,13)}’ | tail -n +3 | sort | un
|
||||
2 volume
|
||||
```
|
||||
|
||||
**NOTE:** The **awk** command selects the Class column from the **lshw** output using $0 (complete lines), but taking only the substrings that start in the correct place (column 36). None of the class entries have more than 13 letters so the substring ends there. The **tail -n +3** part of the command drops the heading and the “=====” line beneath it, so only the 14 device classes are included in the final listing.
|
||||
**注意：** 上面使用 `awk` 命令从 `lshw` 的输出中选择 Class（类别）栏是这样实现的：使用 `$0`（选取完整行），但只取从正确位置（第 36 个字符）开始的子串，而因为“类别”中并没有条目的长度超过 13 个字符，所以子串就在那里结束。命令中 `tail -n +3` 的部分移除了标题和下面的`=====`，所以最终的列表中只包含了那 14 种设备类型。
|
||||
|
||||
One thing you’ll notice is that we get approximately 12 lines of output for each device in the disk class when we don’t use the **-short** option. We see the logical names, such as **/dev/sda**, disk sizes and types, etc.
|
||||
（LCTT 译注：上面的命令中 `awk` 的部分在选取子串时是从第 36 个字符开始的，这个数字基本上取决于最长的设备逻辑名称的长度，因而在不同的系统环境中可能有所不同，一个例子是，当你的系统上有 NVMe SSD 时，可能需要将其改为 41。）
|
||||
|
||||
你会发现在没有使用 `-short` 选项的时候，每一个磁盘类设备都会有大约 12 行的输出，包括像是 `/dev/sda` 这样的逻辑名称，磁盘大小和种类等等。
|
||||
|
||||
```
|
||||
$ sudo lshw -C disk
|
||||
[sudo] password for shs:
|
||||
*-disk:0
|
||||
description: SCSI Disk
|
||||
product: Card Reader-1 card reader?
|
||||
product: Card Reader-1 <== 读卡器？
|
||||
vendor: JIE LI
|
||||
physical id: 0.0.0
|
||||
bus info: scsi@4:0.0.0
|
||||
@ -209,13 +213,13 @@ $ sudo lshw -C disk
|
||||
product: SSD2SC120G1CS175
|
||||
physical id: 0
|
||||
bus info: scsi@0:0.0.0
|
||||
logical name: /dev/sda main system disk
|
||||
logical name: /dev/sda <== 主要磁盘
|
||||
version: 1101
|
||||
serial: PNY20150000778410606
|
||||
size: 111GiB (120GB)
|
||||
capabilities: partitioned partitioned:dos
|
||||
configuration: ansiversion=5 logicalsectorsize=512 sectorsize=512 signature=f63b5929
|
||||
*-cdrom aka /dev/sr0
|
||||
*-cdrom <== 也叫 /dev/sr0
|
||||
description: DVD writer
|
||||
product: DVD+-RW GSA-H73N
|
||||
vendor: HL-DT-ST
|
||||
@ -235,7 +239,7 @@ $ sudo lshw -C disk
|
||||
product: SAMSUNG HE502HJ
|
||||
physical id: 0.0.0
|
||||
bus info: scsi@3:0.0.0
|
||||
logical name: /dev/sdb secondary disk
|
||||
logical name: /dev/sdb <== 次要磁盘
|
||||
version: 0002
|
||||
serial: S2B6J90B501053
|
||||
size: 465GiB (500GB)
|
||||
@ -243,11 +247,9 @@ $ sudo lshw -C disk
|
||||
configuration: ansiversion=5 logicalsectorsize=512 sectorsize=512 signature=7e67ccf3
|
||||
```
|
||||
|
||||
### Wrap-up
|
||||
### 总结
|
||||
|
||||
The **lshw** command provides details that many of us won’t normally deal with. Still, it’s nice to know how much information is available even if you only use a portion of it.
|
||||
|
||||
Join the Network World communities on [Facebook][1] and [LinkedIn][2] to comment on topics that are top of mind.
|
||||
`lshw` 命令提供了一些我们许多人通常不会处理的信息，不过即使你只用了其中的一部分，知道有多少信息可用还是很不错的。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
@ -255,12 +257,13 @@ via: https://www.networkworld.com/article/3583598/how-to-view-information-on-you
|
||||
|
||||
作者：[Sandra Henry-Stocker][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
译者：[rakino](https://github.com/rakino)
|
||||
校对：[wxy](https://github.com/wxy)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://www.networkworld.com/author/Sandra-Henry_Stocker/
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://www.facebook.com/NetworkWorld/
|
||||
[2]: https://www.linkedin.com/company/network-world
|
||||
[1]: https://images.idgesg.net/images/article/2020/02/kali_linux_tools_abstract_gears_binary_data_by_nevarpp_gettyimages-688718788_2400x1600-100832674-large.jpg
|
||||
[2]: https://www.facebook.com/NetworkWorld/
|
||||
[3]: https://www.linkedin.com/company/network-world
|
||||
@ -1,136 +0,0 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (rakino)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (Things You Didn't Know About GNU Readline)
|
||||
[#]: via: (https://twobithistory.org/2019/08/22/readline.html)
|
||||
[#]: author: (Two-Bit History https://twobithistory.org)
|
||||
|
||||
Things You Didn't Know About GNU Readline
|
||||
======
|
||||
|
||||
I sometimes think of my computer as a very large house. I visit this house every day and know most of the rooms on the ground floor, but there are bedrooms I’ve never been in, closets I haven’t opened, nooks and crannies that I’ve never explored. I feel compelled to learn more about my computer the same way anyone would feel compelled to see a room they had never visited in their own home.
|
||||
|
||||
GNU Readline is an unassuming little software library that I relied on for years without realizing that it was there. Tens of thousands of people probably use it every day without thinking about it. If you use the Bash shell, every time you auto-complete a filename, or move the cursor around within a single line of input text, or search through the history of your previous commands, you are using GNU Readline. When you do those same things while using the command-line interface to Postgres (`psql`), say, or the Ruby REPL (`irb`), you are again using GNU Readline. Lots of software depends on the GNU Readline library to implement functionality that users expect, but the functionality is so auxiliary and unobtrusive that I imagine few people stop to wonder where it comes from.
|
||||
|
||||
GNU Readline was originally created in the 1980s by the Free Software Foundation. Today, it is an important if invisible part of everyone’s computing infrastructure, maintained by a single volunteer.
|
||||
|
||||
### Feature Replete
|
||||
|
||||
The GNU Readline library exists primarily to augment any command-line interface with a common set of keystrokes that allow you to move around within and edit a single line of input. If you press `Ctrl-A` at a Bash prompt, for example, that will jump your cursor to the very beginning of the line, while pressing `Ctrl-E` will jump it to the end. Another useful command is `Ctrl-U`, which will delete everything in the line before the cursor.
|
||||
|
||||
For an embarrassingly long time, I moved around on the command line by repeatedly tapping arrow keys. For some reason, I never imagined that there was a faster way to do it. Of course, no programmer familiar with a text editor like Vim or Emacs would deign to punch arrow keys for long, so something like Readline was bound to be created. Using Readline, you can do much more than just jump around—you can edit your single line of text as if you were using a text editor. There are commands to delete words, transpose words, upcase words, copy and paste characters, etc. In fact, most of Readline’s keystrokes/shortcuts are based on Emacs. Readline is essentially Emacs for a single line of text. You can even record and replay macros.
|
||||
|
||||
I have never used Emacs, so I find it hard to remember what all the different Readline commands are. But one thing about Readline that is really neat is that you can switch to using a Vim-based mode instead. To do this for Bash, you can use the `set` builtin. The following will tell Readline to use Vim-style commands for the current shell:
|
||||
|
||||
```
|
||||
$ set -o vi
|
||||
```
|
||||
|
||||
With this option enabled, you can delete words using `dw` and so on. The equivalent to `Ctrl-U` in the Emacs mode would be `d0`.
|
||||
|
||||
I was excited to try this when I first learned about it, but I’ve found that it doesn’t work so well for me. I’m happy that this concession to Vim users exists, and you might have more luck with it than me, particularly if you haven’t already used Readline’s default command keystrokes. My problem is that, by the time I heard about the Vim-based interface, I had already learned several Readline keystrokes. Even with the Vim option enabled, I keep using the default keystrokes by mistake. Also, without some sort of indicator, Vim’s modal design is awkward here—it’s very easy to forget which mode you’re in. So I’m stuck at a local maximum using Vim as my text editor but Emacs-style Readline commands. I suspect a lot of other people are in the same position.
|
||||
|
||||
If you feel, not unreasonably, that both Vim and Emacs’ keyboard command systems are bizarre and arcane, you can customize Readline’s key bindings and make them whatever you like. This is not hard to do. Readline reads a `~/.inputrc` file on startup that can be used to configure various options and key bindings. One thing I’ve done is reconfigured `Ctrl-K`. Normally it deletes from the cursor to the end of the line, but I rarely do that. So I’ve instead bound it so that pressing `Ctrl-K` deletes the whole line, regardless of where the cursor is. I’ve done that by adding the following to `~/.inputrc`:
|
||||
|
||||
```
|
||||
Control-k: kill-whole-line
|
||||
```
|
||||
|
||||
Each Readline command (the documentation refers to them as _functions_) has a name that you can associate with a key sequence this way. If you edit `~/.inputrc` in Vim, it turns out that Vim knows the filetype and will help you by highlighting valid function names but not invalid ones!
|
||||
|
||||
Another thing you can do with `~/.inputrc` is create canned macros by mapping key sequences to input strings. [The Readline manual][1] gives one example that I think is especially useful. I often find myself wanting to save the output of a program to a file, which means that I often append something like `> output.txt` to Bash commands. To save some time, you could make this a Readline macro:
|
||||
|
||||
```
|
||||
Control-o: "> output.txt"
|
||||
```
|
||||
|
||||
Now, whenever you press `Ctrl-O`, you’ll see that `> output.txt` gets added after your cursor on the command line. Neat!
|
||||
|
||||
But with macros you can do more than just create shortcuts for strings of text. The following entry in `~/.inputrc` means that, every time I press `Ctrl-J`, any text I already have on the line is surrounded by `$(` and `)`. The macro moves to the beginning of the line with `Ctrl-A`, adds `$(`, then moves to the end of the line with `Ctrl-E` and adds `)`:
|
||||
|
||||
```
|
||||
Control-j: "\C-a$(\C-e)"
|
||||
```
|
||||
|
||||
This might be useful if you often need the output of one command to use for another, such as in:
|
||||
|
||||
```
|
||||
$ cd $(brew --prefix)
|
||||
```
|
||||
|
||||
The `~/.inputrc` file also allows you to set different values for what the Readline manual calls _variables_. These enable or disable certain Readline behaviors. You can use these variables to change, for example, how Readline auto-completion works or how the Readline history search works. One variable I’d recommend turning on is the `revert-all-at-newline` variable, which by default is off. When the variable is off, if you pull a line from your command history using the reverse search feature, edit it, but then decide to search instead for another line, the edit you made is preserved in the history. I find this confusing because it leads to lines showing up in your Bash command history that you never actually ran. So add this to your `~/.inputrc`:
|
||||
|
||||
```
|
||||
set revert-all-at-newline on
|
||||
```
|
||||
|
||||
When you set options or key bindings using `~/.inputrc`, they apply wherever the Readline library is used. This includes Bash most obviously, but you’ll also get the benefit of your changes in other programs like `irb` and `psql` too! A Readline macro that inserts `SELECT * FROM` could be useful if you often use command-line interfaces to relational databases.
|
||||
|
||||
### Chet Ramey
|
||||
|
||||
GNU Readline is today maintained by Chet Ramey, a Senior Technology Architect at Case Western Reserve University. Ramey also maintains the Bash shell. Both projects were first authored by a Free Software Foundation employee named Brian Fox beginning in 1988. But Ramey has been the sole maintainer since around 1994.
|
||||
|
||||
Ramey told me via email that Readline, far from being an original idea, was created to implement functionality prescribed by the POSIX specification, which in the late 1980s had just been created. Many earlier shells, including the Korn shell and at least one version of the Unix System V shell, included line editing functionality. The 1988 version of the Korn shell (`ksh88`) provided both Emacs-style and Vi/Vim-style editing modes. As far as I can tell from [the manual page][2], the Korn shell would decide which mode you wanted to use by looking at the `VISUAL` and `EDITOR` environment variables, which is pretty neat. The parts of POSIX that specified shell functionality were closely modeled on `ksh88`, so GNU Bash was going to have to implement a similarly flexible line-editing system to stay compliant. Hence Readline.
|
||||
|
||||
When Ramey first got involved in Bash development, Readline was a single source file in the Bash project directory. It was really just a part of Bash. Over time, the Readline file slowly moved toward becoming an independent project, though it was not until 1994 (with the 2.0 release of Readline) that Readline became a separate library entirely.
|
||||
|
||||
Readline is closely associated with Bash, and Ramey usually pairs Readline releases with Bash releases. But as I mentioned above, Readline is a library that can be used by any software implementing a command-line interface. And it’s really easy to use. This is a simple example, but here’s how you would you use Readline in your own C program. The string argument to the `readline()` function is the prompt that you want Readline to display to the user:
|
||||
|
||||
```
|
||||
#include <stdio.h>
|
||||
#include <stdlib.h>
|
||||
#include "readline/readline.h"
|
||||
|
||||
int main(int argc, char** argv)
|
||||
{
|
||||
char* line = readline("my-rl-example> ");
|
||||
printf("You entered: \"%s\"\n", line);
|
||||
|
||||
free(line);
|
||||
|
||||
return 0;
|
||||
}
|
||||
```
|
||||
|
||||
Your program hands off control to Readline, which is responsible for getting a line of input from the user (in such a way that allows the user to do all the fancy line-editing things). Once the user has actually submitted the line, Readline returns it to you. I was able to compile the above by linking against the Readline library, which I apparently have somewhere in my library search path, by invoking the following:
|
||||
|
||||
```
|
||||
$ gcc main.c -lreadline
|
||||
```
|
||||
|
||||
The Readline API is much more extensive than that single function of course, and anyone using it can tweak all sorts of things about the library’s behavior. Library users can even add new functions that end users can configure via `~/.inputrc`, meaning that Readline is very easy to extend. But, as far as I can tell, even Bash ultimately calls the simple `readline()` function to get input just as in the example above, though there is a lot of configuration beforehand. (See [this line][3] in the source for GNU Bash, which seems to be where Bash hands off responsibility for getting input to Readline.)
|
||||
|
||||
Ramey has now worked on Bash and Readline for well over a decade. He has never once been compensated for his work—he is and has always been a volunteer. Bash and Readline continue to be actively developed, though Ramey said that Readline changes much more slowly than Bash does. I asked Ramey what it was like being the sole maintainer of software that so many people use. He said that millions of people probably use Bash without realizing it (because every Apple device runs Bash), which makes him worry about how much disruption a breaking change might cause. But he’s slowly gotten used to the idea of all those people out there. He said that he continues to work on Bash and Readline because at this point he is deeply invested and because he simply likes to make useful software available to the world.
|
||||
|
||||
_You can find more information about Chet Ramey at [his website][4]._
|
||||
|
||||
_If you enjoyed this post, more like it come out every four weeks! Follow [@TwoBitHistory][5] on Twitter or subscribe to the [RSS feed][6] to make sure you know when a new post is out._
|
||||
|
||||
_Previously on TwoBitHistory…_
|
||||
|
||||
> Please enjoy my long overdue new post, in which I use the story of the BBC Micro and the Computer Literacy Project as a springboard to complain about Codecademy.<https://t.co/PiWlKljDjK>
|
||||
>
|
||||
> — TwoBitHistory (@TwoBitHistory) [March 31, 2019][7]
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://twobithistory.org/2019/08/22/readline.html
|
||||
|
||||
作者：[Two-Bit History][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://twobithistory.org
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://tiswww.case.edu/php/chet/readline/readline.html
|
||||
[2]: https://web.archive.org/web/20151105130220/http://www2.research.att.com/sw/download/man/man1/ksh88.html
|
||||
[3]: https://github.com/bminor/bash/blob/9f597fd10993313262cab400bf3c46ffb3f6fd1e/parse.y#L1487
|
||||
[4]: https://tiswww.case.edu/php/chet/
|
||||
[5]: https://twitter.com/TwoBitHistory
|
||||
[6]: https://twobithistory.org/feed.xml
|
||||
[7]: https://twitter.com/TwoBitHistory/status/1112492084383092738?ref_src=twsrc%5Etfw
|
||||
@ -0,0 +1,92 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (Telcos Move from Black boxes to Open Source)
|
||||
[#]: via: (https://www.linux.com/interviews/telcos-move-from-black-boxes-to-open-source/)
|
||||
[#]: author: (Swapnil Bhartiya https://www.linux.com/author/swapnil/)
|
||||
|
||||
Telcos Move from Black boxes to Open Source
|
||||
======
|
||||
|
||||
*Linux Foundation Networking (LFN) organized its first virtual event last week and we sat down with Arpit Joshipura, the General Manager of Networking, IoT and Edge at the Linux Foundation, to talk about the key points of the event and how LFN is leading the adoption of open source within the telco space. *
|
||||
|
||||
**Swapnil Bhartiya: Today, we have with us Arpit Joshipura, General Manager of Networking, IoT and Edge, at the Linux Foundation. Arpit, what were some of the highlights of this event? Some big announcements that you can talk about?**
|
||||
|
||||
**Arpit Joshipura:** This was a global event with more than 80 sessions and was attended by attendees from over 75 countries. The sessions were very diverse. A lot of the sessions were end-user driven, operator driven as well as from our vendors and partners. If you take LF Networking and LFH as two umbrellas that are leading the Networking and Edge implementations here, we had a very significant announcement. I would probably group them into 5 main things:
|
||||
|
||||
Number one, we released a white paper at the Linux Foundation level where we had a bunch of vertical industries transformed using open source. These are over 100-year-old industries like telecom, automotive, finance, energy, healthcare, etc. So, that’s kind of one big announcement where vertical industries have taken advantage of open source.
|
||||
|
||||
The second announcement was easy enough: Google Cloud joins Linux Foundation Networking as a partner. That announcement comes on the basis of the telecom market and the cloud market converging together and building on each other.
|
||||
|
||||
The third major announcement was a project under LF Networking. If you remember, two years ago, a project collaboration with GSMA was started. It was called CNTT, which really defined and narrowed the scope of interoperability and compliance. And we have OPNFV under LFN. What we announced at Open Networking and Edge summit is the two projects are going to come together. This would be fantastic to a global community of operators who are simplifying the deployment and interoperability of implementation of NFVI manual VNFs and CNFs.
|
||||
|
||||
The next announcement was around a research study that we released on open source code that was created by Linux Foundation Networking, using LFN analytics and COCOMO estimation. We’re talking $7.2 billion worth of IP investment, right? This is the power of shared technology.
|
||||
|
||||
And finally, we released a survey on the Edge community asking them, “Why are you contributing to open source?” And the answer was fascinating. It was all-around innovation, speed to deployment, market creation. Yes, cost was important, but not initially.
|
||||
|
||||
So those were the 5 big highlights of the show from an LFN and LFH perspective.
|
||||
|
||||
**Swapnil Bhartiya: There are two things that I’m interested in. One is the consolidation that you talk about, and the second is survey. The fact is that everybody is using open source. There is no doubt about it. But the problem that is happening is since everybody’s using it, there seems to be some gap between the awareness of how to be a good open source citizen as well. What have you seen in the telco space?**
|
||||
|
||||
**Arpit Joshipura:** First of all, 5 years ago, they were all using black box and proprietary technologies. Then, we launched a project called OpenDaylight. And of course, OpenDaylight announced its 13th release today, but that’s kind of on their 6-year anniversary from being proprietary to today in one of the more active projects called ONAP. The telcos are 4 of the Top 10 contributors of source code and open source, right? Who would have imagined that an AT&T, Verizon, Amdocs, DT, Vodafone, and a China mobile and a China telecom, you name it are all actively contributing code? So that’s a paradigm shift in terms of not only consuming it, but also contributing towards it.
|
||||
|
||||
**Swapnil Bhartiya: And since you mentioned ONAP, if I’m not wrong, I think AT&T released its own work as E-com. And then the projects within the Foundation were merged to create ONAP. And then you mentioned actually NTD. So, what I want to understand from you is how many projects are there that you see within the Foundation? The problem is that Linux Foundation and all those other foundations are open servers. It’s a very good place for those products to come in. It’s obvious that there will be some projects that will overlap. So what is the situation right now? Where do you see some overlap happening and, at the same time, are there still gaps that you need to fill?**
|
||||
|
||||
**Arpit Joshipura:** So that’s a question of the philosophies of a foundation, right? I’ll start off with the most loose situation, which is GitHub. Millions and millions of projects on GitHub. Any PhD student can throw his code on GitHub and say that’s open source and at the end of the day, if there’s no community around it, that project is dead. Okay. That’s the most extreme scenario. Then, there are foundations like CNCF who have a process of accepting projects that could have competing solutions. May the best project win.
|
||||
|
||||
From an LF Networking and LFH perspective, the process is a little bit more restrictive: there is a formal project life cycle document and a process available on the Wiki that looks at the complementary nature of the project, that looks at the ecosystem, that looks at how it will enable and foster innovation. Then based on that, the governing board and the neutral governance that we have set up under the Linux Foundation, they would approve it.
|
||||
|
||||
Overall, it depends on the philosophy for LFN and LFH. We have 8 projects each in the umbrella, and most of these projects are quite complementary when it comes to solving different use cases in different parts of the network.
|
||||
|
||||
**Swapnil Bhartiya: Awesome. Now, I want to talk about 5G a bit. I did not hear any announcements, but can you talk a bit about what is the word going on to help the further deployment of 5G technologies?**
|
||||
|
||||
**Arpit Joshipura:** Yeah. I’m happy and sad to say that 5G is old news, right? The reality is all of the infrastructure work on 5G already was released earlier this year. So ONAP Frankfurt release, for example, has a blueprint on 5G slicing, right? All the work has been done, lots of blueprint and Akraino using 5G and mech. So, that work is done. The cities are getting lit up by the carriers. You see announcements from global carriers on 5G deployments. I think there are 2 missing pieces of work remaining for 5G.
|
||||
|
||||
One is obviously the O-RAN support, right? The O-RAN software community, which we host at the Linux Foundation also is coming up with a second release. And, all the support for 5G is in there.
|
||||
|
||||
The second part of 5G is really the compliance and verification testing. A lot of work is going into CMTT and OPN and feed. Remember that merge project we talked about where 5G is in context of not just OpenStack, but also Kubernetes? So the cloud-native aspects of 5G are all being worked on this year. I think we’ll see a lot more cloud-native 5G deployments next year primarily because projects like ONAP or cloud native integrate with projects like ONAP and Anthos or Azure stack and things like that.
|
||||
|
||||
**Swapnil Bhartiya: What are some of the biggest challenges that the telco industry is facing? I mean, technically, no externalization and all those things were there, but foundations have solved the problem. Some rough ideas are still there that you’re trying to resolve for them.**
|
||||
|
||||
**Arpit Joshipura:** Yeah. I think the recent pandemic caused a significant change in the telcos’ thinking, right? Fortunately, because they had already started on a virtualization and open-source route, you heard from Android, and you heard from Deutsche Telekom, and you heard from Achronix, all of the operators were able to handle the change in the network traffic, change in the network, traffic direction, SLS workloads, etc., right? All because of the _softwarization_ as we call it on the network.
|
||||
|
||||
Given the pandemic, I think the first challenge for them was, can the network hold up? And the answer is, yes. Right? All the work-from-home and all these video recordings, we have to hang out with the web, that was number one.
|
||||
|
||||
Number two is it’s good to hold up the network, but did I end up spending millions and millions of dollars for operational expenditures? And the answer to that is no, especially for the telcos who have embraced an open-source ecosystem, right? So people who have deployed projects like SDN or ONAP or automation and orchestration or closed-loop controls, they automatically configure and reconfigure based on workloads and services and traffic, right? And that does not require manual labor, right? Tremendous amounts of costs were saved from an opex perspective, right?
|
||||
|
||||
For operators who are still in the old mindset have significantly increased their opex, and what that has caused is a real strain on their budget sheets.
|
||||
|
||||
So those were the 2 big things that we felt were challenges, but have been solved. Going forward, now it’s just a quick rollout/build-out of 5G, expanding 5G to Edge, and then partnering with the public cloud providers, at least, here in the US to bring the cloud-native solutions to market.
|
||||
|
||||
**Swapnil Bhartiya: Awesome. Now, Arpit, if I’m not wrong, LF Edge is I think, going to celebrate its second anniversary in January. What do you feel the product has achieved so far? What are its accomplishments? And what are some challenges that the project still has to tackle?**
|
||||
|
||||
**Arpit Joshipura:** Let me start off with the most important accomplishment as a community and that is terminology. We have a project called State of the Edge and we just issued a white paper, which outlines terminology, terms and definitions of what Edge is because, historically, people use terms like thin edge, thick edge, cloud edge, far edge, near edge and blah, blah, blah. They’re all relative terms. Okay. It’s an edge in relation to who I am.
|
||||
|
||||
Instead of that, the paper now defines absolute terms. If I give you a quick example, there are really 2 kinds of edges. There’s a device edge, and then there is a service provider edge. A device edge is really controlled by the operator, by the end user, I should say. Service provider edge is really shared as a service and the last mile typically separates them.
|
||||
|
||||
Now, if you double click on each of these categories, then you have several incarnations of an edge. You can have an extremely constrained edge, microcontrollers, etc., mostly manufacturing, IIoT type. You could have a smart device edge like gateways, etc. Or you could have an on-prem silver type device edge. Either way, an end user controls that edge versus the other edge. Whether it’s on the radio-based stations or in a smart central office, the operator controls it. So that’s kind of the first accomplishment, right? Standardizing on terminology.
|
||||
|
||||
The second big Edge accomplishment is around 2 projects: Akraino and EdgeX Foundry. These are stage 3 mature projects. They have come out with significant [results]. Akraino, for example, has come out with 20 plus blueprints. These are blueprints that actually can be deployed today, right? Just to refresh, a blueprint is a declarative configuration that has everything from end to end to solve a particular use case. So things like connected classrooms, AR/VR, connected cars, right? Network cloud, smart factories, smart cities, etc. So all these are available today.
|
||||
|
||||
EdgeX is the IoT framework for an industrial setup, and that’s kind of the most downloaded. Those 2 projects, along with Fledge, EVE, Baetyl, Home Edge, Open Horizon, security advanced onboarding, NSoT, right? Very, very strong growth over 200% growth in terms of contributions. Huge growth in membership, huge growth in new projects and the community overall. We’re seeing that Edge is really picking up great. Remember, I told you Edge is 4 times the size of the cloud. So, everybody is in it.
|
||||
|
||||
**Swapnil Bhartiya: Now, the second part of the question was also some of the challenges that are still there. You talked about accomplishment. What are the problems that you see that you still think that the project has to solve for the industry and the community?**
|
||||
|
||||
**Arpit Joshipura:** The fundamental challenge that remains is we’re still working as a community in different markets. I think the vendor ecosystem is trying to figure out who is the customer and who is the provider, right? Think of it this way: a carrier, for example, AT&T, could be a provider to a manufacturing factory, who actually could consume something from a provider, and then ship it to an end user. So, there’s like a value shift, if you may, in the business world, on who gets the cut, if you may. That’s still a challenge. People are trying to figure out, I think people who are going to be quick to define, solve and implement solutions using open technology will probably turn out to be winners.
|
||||
|
||||
People who will just do analysis per analysis will be left behind like any other industry. I think that is kind of fundamentally number one. And number two, I think the speed at which we want to solve things. The pandemic has just accelerated the need for Edge and 5G. I think people are just eager to get gaming with low latency, get manufacturing, predictive maintenance with low latency, home surveillance with low latency, connected cars, autonomous driving, all the classroom use cases. They should have been done next year, but because of the pandemic, it just got accelerated.
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://www.linux.com/interviews/telcos-move-from-black-boxes-to-open-source/
|
||||
|
||||
作者：[Swapnil Bhartiya][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://www.linux.com/author/swapnil/
|
||||
[b]: https://github.com/lujun9972
|
||||
@ -1,3 +1,12 @@
|
||||
[#]: collector: (oska874)
|
||||
[#]: translator: (gxlct008)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (Go on very small hardware (Part 2))
|
||||
[#]: via: (https://ziutek.github.io/2018/04/14/go_on_very_small_hardware2.html)
|
||||
[#]: author: (Michał Derkacz https://ziutek.github.io/)
|
||||
|
||||
Go on very small hardware (Part 2)
|
||||
============================================================
|
||||
|
||||
|
||||
@ -1,315 +0,0 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (gxlct008)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (Building a Messenger App: Messages)
|
||||
[#]: via: (https://nicolasparada.netlify.com/posts/go-messenger-messages/)
|
||||
[#]: author: (Nicolás Parada https://nicolasparada.netlify.com/)
|
||||
|
||||
Building a Messenger App: Messages
|
||||
======
|
||||
|
||||
This post is the 4th on a series:
|
||||
|
||||
* [Part 1: Schema][1]
|
||||
* [Part 2: OAuth][2]
|
||||
* [Part 3: Conversations][3]
|
||||
|
||||
|
||||
|
||||
In this post we’ll code the endpoints to create a message and list them, also an endpoint to update the last time the participant read messages. Start by adding these routes in the `main()` function.
|
||||
|
||||
```
|
||||
router.HandleFunc("POST", "/api/conversations/:conversationID/messages", requireJSON(guard(createMessage)))
|
||||
router.HandleFunc("GET", "/api/conversations/:conversationID/messages", guard(getMessages))
|
||||
router.HandleFunc("POST", "/api/conversations/:conversationID/read_messages", guard(readMessages))
|
||||
```
|
||||
|
||||
Messages goes into conversations so the endpoint includes the conversation ID.
|
||||
|
||||
### Create Message
|
||||
|
||||
This endpoint handles POST requests to `/api/conversations/{conversationID}/messages` with a JSON body with just the message content and return the newly created message. It has two side affects: it updates the conversation `last_message_id` and updates the participant `messages_read_at`.
|
||||
|
||||
```
|
||||
func createMessage(w http.ResponseWriter, r *http.Request) {
|
||||
var input struct {
|
||||
Content string `json:"content"`
|
||||
}
|
||||
defer r.Body.Close()
|
||||
if err := json.NewDecoder(r.Body).Decode(&input); err != nil {
|
||||
http.Error(w, err.Error(), http.StatusBadRequest)
|
||||
return
|
||||
}
|
||||
|
||||
errs := make(map[string]string)
|
||||
input.Content = removeSpaces(input.Content)
|
||||
if input.Content == "" {
|
||||
errs["content"] = "Message content required"
|
||||
} else if len([]rune(input.Content)) > 480 {
|
||||
errs["content"] = "Message too long. 480 max"
|
||||
}
|
||||
if len(errs) != 0 {
|
||||
respond(w, Errors{errs}, http.StatusUnprocessableEntity)
|
||||
return
|
||||
}
|
||||
|
||||
ctx := r.Context()
|
||||
authUserID := ctx.Value(keyAuthUserID).(string)
|
||||
conversationID := way.Param(ctx, "conversationID")
|
||||
|
||||
tx, err := db.BeginTx(ctx, nil)
|
||||
if err != nil {
|
||||
respondError(w, fmt.Errorf("could not begin tx: %v", err))
|
||||
return
|
||||
}
|
||||
defer tx.Rollback()
|
||||
|
||||
isParticipant, err := queryParticipantExistance(ctx, tx, authUserID, conversationID)
|
||||
if err != nil {
|
||||
respondError(w, fmt.Errorf("could not query participant existance: %v", err))
|
||||
return
|
||||
}
|
||||
|
||||
if !isParticipant {
|
||||
http.Error(w, "Conversation not found", http.StatusNotFound)
|
||||
return
|
||||
}
|
||||
|
||||
var message Message
|
||||
if err := tx.QueryRowContext(ctx, `
|
||||
INSERT INTO messages (content, user_id, conversation_id) VALUES
|
||||
($1, $2, $3)
|
||||
RETURNING id, created_at
|
||||
`, input.Content, authUserID, conversationID).Scan(
|
||||
&message.ID,
|
||||
&message.CreatedAt,
|
||||
); err != nil {
|
||||
respondError(w, fmt.Errorf("could not insert message: %v", err))
|
||||
return
|
||||
}
|
||||
|
||||
if _, err := tx.ExecContext(ctx, `
|
||||
UPDATE conversations SET last_message_id = $1
|
||||
WHERE id = $2
|
||||
`, message.ID, conversationID); err != nil {
|
||||
respondError(w, fmt.Errorf("could not update conversation last message ID: %v", err))
|
||||
return
|
||||
}
|
||||
|
||||
if err = tx.Commit(); err != nil {
|
||||
respondError(w, fmt.Errorf("could not commit tx to create a message: %v", err))
|
||||
return
|
||||
}
|
||||
|
||||
go func() {
|
||||
if err = updateMessagesReadAt(nil, authUserID, conversationID); err != nil {
|
||||
log.Printf("could not update messages read at: %v\n", err)
|
||||
}
|
||||
}()
|
||||
|
||||
message.Content = input.Content
|
||||
message.UserID = authUserID
|
||||
message.ConversationID = conversationID
|
||||
// TODO: notify about new message.
|
||||
message.Mine = true
|
||||
|
||||
respond(w, message, http.StatusCreated)
|
||||
}
|
||||
```
|
||||
|
||||
First, it decodes the request body into an struct with the message content. Then, it validates the content is not empty and has less than 480 characters.
|
||||
|
||||
```
|
||||
var rxSpaces = regexp.MustCompile("\\s+")
|
||||
|
||||
func removeSpaces(s string) string {
|
||||
if s == "" {
|
||||
return s
|
||||
}
|
||||
|
||||
lines := make([]string, 0)
|
||||
for _, line := range strings.Split(s, "\n") {
|
||||
line = rxSpaces.ReplaceAllLiteralString(line, " ")
|
||||
line = strings.TrimSpace(line)
|
||||
if line != "" {
|
||||
lines = append(lines, line)
|
||||
}
|
||||
}
|
||||
return strings.Join(lines, "\n")
|
||||
}
|
||||
```
|
||||
|
||||
This is the function to remove spaces. It iterates over each line, remove more than two consecutives spaces and returns with the non empty lines.
|
||||
|
||||
After the validation, it starts an SQL transaction. First, it queries for the participant existance in the conversation.
|
||||
|
||||
```
|
||||
func queryParticipantExistance(ctx context.Context, tx *sql.Tx, userID, conversationID string) (bool, error) {
|
||||
if ctx == nil {
|
||||
ctx = context.Background()
|
||||
}
|
||||
var exists bool
|
||||
if err := tx.QueryRowContext(ctx, `SELECT EXISTS (
|
||||
SELECT 1 FROM participants
|
||||
WHERE user_id = $1 AND conversation_id = $2
|
||||
)`, userID, conversationID).Scan(&exists); err != nil {
|
||||
return false, err
|
||||
}
|
||||
return exists, nil
|
||||
}
|
||||
```
|
||||
|
||||
I extracted it into a function because it’s reused later.
|
||||
|
||||
If the user isn’t participant of the conversation, we return with a `404 Not Found` error.
|
||||
|
||||
Then, it inserts the message and updates the conversation `last_message_id`. Since this point, `last_message_id` cannot by `NULL` because we don’t allow removing messages.
|
||||
|
||||
Then it commits the transaction and we update the participant `messages_read_at` in a goroutine.
|
||||
|
||||
```
|
||||
func updateMessagesReadAt(ctx context.Context, userID, conversationID string) error {
|
||||
if ctx == nil {
|
||||
ctx = context.Background()
|
||||
}
|
||||
|
||||
if _, err := db.ExecContext(ctx, `
|
||||
UPDATE participants SET messages_read_at = now()
|
||||
WHERE user_id = $1 AND conversation_id = $2
|
||||
`, userID, conversationID); err != nil {
|
||||
return err
|
||||
}
|
||||
return nil
|
||||
}
|
||||
```
|
||||
|
||||
Before responding with the new message, we must notify about it. This is for the realtime part we’ll code in the next post so I left a comment there.
|
||||
|
||||
### Get Messages
|
||||
|
||||
This endpoint handles GET requests to `/api/conversations/{conversationID}/messages`. It responds with a JSON array with all the messages in the conversation. It also has the same side affect of updating the participant `messages_read_at`.
|
||||
|
||||
```
|
||||
func getMessages(w http.ResponseWriter, r *http.Request) {
|
||||
ctx := r.Context()
|
||||
authUserID := ctx.Value(keyAuthUserID).(string)
|
||||
conversationID := way.Param(ctx, "conversationID")
|
||||
|
||||
tx, err := db.BeginTx(ctx, &sql.TxOptions{ReadOnly: true})
|
||||
if err != nil {
|
||||
respondError(w, fmt.Errorf("could not begin tx: %v", err))
|
||||
return
|
||||
}
|
||||
defer tx.Rollback()
|
||||
|
||||
isParticipant, err := queryParticipantExistance(ctx, tx, authUserID, conversationID)
|
||||
if err != nil {
|
||||
respondError(w, fmt.Errorf("could not query participant existance: %v", err))
|
||||
return
|
||||
}
|
||||
|
||||
if !isParticipant {
|
||||
http.Error(w, "Conversation not found", http.StatusNotFound)
|
||||
return
|
||||
}
|
||||
|
||||
rows, err := tx.QueryContext(ctx, `
|
||||
SELECT
|
||||
id,
|
||||
content,
|
||||
created_at,
|
||||
user_id = $1 AS mine
|
||||
FROM messages
|
||||
WHERE messages.conversation_id = $2
|
||||
ORDER BY messages.created_at DESC
|
||||
`, authUserID, conversationID)
|
||||
if err != nil {
|
||||
respondError(w, fmt.Errorf("could not query messages: %v", err))
|
||||
return
|
||||
}
|
||||
defer rows.Close()
|
||||
|
||||
messages := make([]Message, 0)
|
||||
for rows.Next() {
|
||||
var message Message
|
||||
if err = rows.Scan(
|
||||
&message.ID,
|
||||
&message.Content,
|
||||
&message.CreatedAt,
|
||||
&message.Mine,
|
||||
); err != nil {
|
||||
respondError(w, fmt.Errorf("could not scan message: %v", err))
|
||||
return
|
||||
}
|
||||
|
||||
messages = append(messages, message)
|
||||
}
|
||||
|
||||
if err = rows.Err(); err != nil {
|
||||
respondError(w, fmt.Errorf("could not iterate over messages: %v", err))
|
||||
return
|
||||
}
|
||||
|
||||
if err = tx.Commit(); err != nil {
|
||||
respondError(w, fmt.Errorf("could not commit tx to get messages: %v", err))
|
||||
return
|
||||
}
|
||||
|
||||
go func() {
|
||||
if err = updateMessagesReadAt(nil, authUserID, conversationID); err != nil {
|
||||
log.Printf("could not update messages read at: %v\n", err)
|
||||
}
|
||||
}()
|
||||
|
||||
respond(w, messages, http.StatusOK)
|
||||
}
|
||||
```
|
||||
|
||||
First, it begins an SQL transaction in readonly mode. Checks for the participant existance and queries all the messages. In each message, we use the current authenticated user ID to know whether the user owns the message (`mine`). Then it commits the transaction, updates the participant `messages_read_at` in a goroutine and respond with the messages.
|
||||
|
||||
### Read Messages
|
||||
|
||||
This endpoint handles POST requests to `/api/conversations/{conversationID}/read_messages`. Without any request or response body. In the frontend we’ll make this request each time a new message arrive in the realtime stream.
|
||||
|
||||
```
|
||||
func readMessages(w http.ResponseWriter, r *http.Request) {
|
||||
ctx := r.Context()
|
||||
authUserID := ctx.Value(keyAuthUserID).(string)
|
||||
conversationID := way.Param(ctx, "conversationID")
|
||||
|
||||
if err := updateMessagesReadAt(ctx, authUserID, conversationID); err != nil {
|
||||
respondError(w, fmt.Errorf("could not update messages read at: %v", err))
|
||||
return
|
||||
}
|
||||
|
||||
w.WriteHeader(http.StatusNoContent)
|
||||
}
|
||||
```
|
||||
|
||||
It uses the same function we’ve been using to update the participant `messages_read_at`.
|
||||
|
||||
* * *
|
||||
|
||||
That concludes it. Realtime messages is the only part left in the backend. Wait for it in the next post.
|
||||
|
||||
[Souce Code][4]
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://nicolasparada.netlify.com/posts/go-messenger-messages/
|
||||
|
||||
作者：[Nicolás Parada][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://nicolasparada.netlify.com/
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://nicolasparada.netlify.com/posts/go-messenger-schema/
|
||||
[2]: https://nicolasparada.netlify.com/posts/go-messenger-oauth/
|
||||
[3]: https://nicolasparada.netlify.com/posts/go-messenger-conversations/
|
||||
[4]: https://github.com/nicolasparada/go-messenger-demo
|
||||
@ -1,175 +0,0 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (Building a Messenger App: Realtime Messages)
|
||||
[#]: via: (https://nicolasparada.netlify.com/posts/go-messenger-realtime-messages/)
|
||||
[#]: author: (Nicolás Parada https://nicolasparada.netlify.com/)
|
||||
|
||||
Building a Messenger App: Realtime Messages
|
||||
======
|
||||
|
||||
This post is the 5th on a series:
|
||||
|
||||
* [Part 1: Schema][1]
|
||||
* [Part 2: OAuth][2]
|
||||
* [Part 3: Conversations][3]
|
||||
* [Part 4: Messages][4]
|
||||
|
||||
|
||||
|
||||
For realtime messages we’ll use [Server-Sent Events][5]. This is an open connection in which we can stream data. We’ll have and endpoint in which the user subscribes to all the messages sended to him.
|
||||
|
||||
### Message Clients
|
||||
|
||||
Before the HTTP part, let’s code a map to have all the clients listening for messages. Initialize this globally like so:
|
||||
|
||||
```
|
||||
type MessageClient struct {
|
||||
Messages chan Message
|
||||
UserID string
|
||||
}
|
||||
|
||||
var messageClients sync.Map
|
||||
```
|
||||
|
||||
### New Message Created
|
||||
|
||||
Remember in the [last post][4] when we created the message, we left a “TODO” comment. There we’ll dispatch a goroutine with this function.
|
||||
|
||||
```
|
||||
go messageCreated(message)
|
||||
```
|
||||
|
||||
Insert that line just where we left the comment.
|
||||
|
||||
```
|
||||
func messageCreated(message Message) error {
|
||||
if err := db.QueryRow(`
|
||||
SELECT user_id FROM participants
|
||||
WHERE user_id != $1 and conversation_id = $2
|
||||
`, message.UserID, message.ConversationID).
|
||||
Scan(&message.ReceiverID); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
go broadcastMessage(message)
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
func broadcastMessage(message Message) {
|
||||
messageClients.Range(func(key, _ interface{}) bool {
|
||||
client := key.(*MessageClient)
|
||||
if client.UserID == message.ReceiverID {
|
||||
client.Messages <- message
|
||||
}
|
||||
return true
|
||||
})
|
||||
}
|
||||
```
|
||||
|
||||
The function queries for the recipient ID (the other participant ID) and sends the message to all the clients.
|
||||
|
||||
### Subscribe to Messages
|
||||
|
||||
Lets go to the `main()` function and add this route:
|
||||
|
||||
```
|
||||
router.HandleFunc("GET", "/api/messages", guard(subscribeToMessages))
|
||||
```
|
||||
|
||||
This endpoint handles GET requests on `/api/messages`. The request should be an [EventSource][6] connection. It responds with an event stream in which the data is JSON formatted.
|
||||
|
||||
```
|
||||
func subscribeToMessages(w http.ResponseWriter, r *http.Request) {
|
||||
if a := r.Header.Get("Accept"); !strings.Contains(a, "text/event-stream") {
|
||||
http.Error(w, "This endpoint requires an EventSource connection", http.StatusNotAcceptable)
|
||||
return
|
||||
}
|
||||
|
||||
f, ok := w.(http.Flusher)
|
||||
if !ok {
|
||||
respondError(w, errors.New("streaming unsupported"))
|
||||
return
|
||||
}
|
||||
|
||||
ctx := r.Context()
|
||||
authUserID := ctx.Value(keyAuthUserID).(string)
|
||||
|
||||
h := w.Header()
|
||||
h.Set("Cache-Control", "no-cache")
|
||||
h.Set("Connection", "keep-alive")
|
||||
h.Set("Content-Type", "text/event-stream")
|
||||
|
||||
messages := make(chan Message)
|
||||
defer close(messages)
|
||||
|
||||
client := &MessageClient{Messages: messages, UserID: authUserID}
|
||||
messageClients.Store(client, nil)
|
||||
defer messageClients.Delete(client)
|
||||
|
||||
for {
|
||||
select {
|
||||
case <-ctx.Done():
|
||||
return
|
||||
case message := <-messages:
|
||||
if b, err := json.Marshal(message); err != nil {
|
||||
log.Printf("could not marshall message: %v\n", err)
|
||||
fmt.Fprintf(w, "event: error\ndata: %v\n\n", err)
|
||||
} else {
|
||||
fmt.Fprintf(w, "data: %s\n\n", b)
|
||||
}
|
||||
f.Flush()
|
||||
}
|
||||
}
|
||||
}
|
||||
```
|
||||
|
||||
First it checks for the correct request headers and checks the server supports streaming. We create a channel of messages to make a client and store it in the clients map. Each time a new message is created, it will go in this channel, so we can read from it with a `for-select` loop.
|
||||
|
||||
Server-Sent Events uses this format to send data:
|
||||
|
||||
```
|
||||
data: some data here\n\n
|
||||
```
|
||||
|
||||
We are sending it in JSON format:
|
||||
|
||||
```
|
||||
data: {"foo":"bar"}\n\n
|
||||
```
|
||||
|
||||
We are using `fmt.Fprintf()` to write to the response writter in this format and flushing the data in each iteration of the loop.
|
||||
|
||||
This will loop until the connection is closed using the request context. We defered the close of the channel and the delete of the client, so when the loop ends, the channel will be closed and the client won’t receive more messages.
|
||||
|
||||
Note aside, the JavaScript API to work with Server-Sent Events (EventSource) doesn’t support setting custom headers 😒 So we cannot set `Authorization: Bearer <token>`. And that’s the reason why the `guard()` middleware reads the token from the URL query string also.
|
||||
|
||||
* * *
|
||||
|
||||
That concludes the realtime messages. I’d like to say that’s everything in the backend, but to code the frontend I’ll add one more endpoint to login. A login that will be just for development.
|
||||
|
||||
[Souce Code][7]
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://nicolasparada.netlify.com/posts/go-messenger-realtime-messages/
|
||||
|
||||
作者：[Nicolás Parada][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://nicolasparada.netlify.com/
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://nicolasparada.netlify.com/posts/go-messenger-schema/
|
||||
[2]: https://nicolasparada.netlify.com/posts/go-messenger-oauth/
|
||||
[3]: https://nicolasparada.netlify.com/posts/go-messenger-conversations/
|
||||
[4]: https://nicolasparada.netlify.com/posts/go-messenger-messages/
|
||||
[5]: https://developer.mozilla.org/en-US/docs/Web/API/Server-sent_events
|
||||
[6]: https://developer.mozilla.org/en-US/docs/Web/API/EventSource
|
||||
[7]: https://github.com/nicolasparada/go-messenger-demo
|
||||
@ -1,265 +0,0 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (Using Yarn on Ubuntu and Other Linux Distributions)
|
||||
[#]: via: (https://itsfoss.com/install-yarn-ubuntu)
|
||||
[#]: author: (Abhishek Prakash https://itsfoss.com/author/abhishek/)
|
||||
|
||||
Using Yarn on Ubuntu and Other Linux Distributions
|
||||
======
|
||||
|
||||
**This quick tutorial shows you the official way of installing Yarn package manager on Ubuntu and Debian Linux. You’ll also learn some basic Yarn commands and the steps to remove Yarn completely.**
|
||||
|
||||
[Yarn][1] is an open source JavaScript package manager developed by Facebook. It is an alternative or should I say improvement to the popular npm package manager. [Facebook developers’ team][2] created Yarn to overcome the shortcomings of [npm][3]. Facebook claims that Yarn is faster, reliable and more secure than npm.
|
||||
|
||||
Like npm, Yarn provides you a way to automate the process of installing, updating, configuring, and removing packages retrieved from a global registry.
|
||||
|
||||
The advantage of Yarn is that it is faster as it caches every package it downloads so it doesn’t need to download it again. It also parallelizes operations to maximize resource utilization. Yarn also uses [checksums to verify the integrity][4] of every installed package before its code is executed. Yarn also guarantees that an install that worked on one system will work exactly the same way on any other system.
|
||||
|
||||
If you are [using nodejs on Ubuntu][5], probably you already have npm installed on your system. In that case, you can use npm to install Yarn globally in the following manner:
|
||||
|
||||
```
|
||||
sudo npm install yarn -g
|
||||
```
|
||||
|
||||
However, I would recommend using the official way to install Yarn on Ubuntu/Debian.
|
||||
|
||||
### Installing Yarn on Ubuntu and Debian [The Official Way]
|
||||
|
||||
![Yarn JS][6]
|
||||
|
||||
The instructions mentioned here should be applicable to all versions of Ubuntu such as Ubuntu 18.04, 16.04 etc. The same set of instructions are also valid for Debian and other Debian based distributions.
|
||||
|
||||
Since the tutorial uses Curl to add the GPG key of Yarn project, it would be a good idea to verify whether you have Curl installed already or not.
|
||||
|
||||
```
|
||||
sudo apt install curl
|
||||
```
|
||||
|
||||
The above command will install Curl if it wasn’t installed already. Now that you have curl, you can use it to add the GPG key of Yarn project in the following fashion:
|
||||
|
||||
```
|
||||
curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | sudo apt-key add -
|
||||
```
|
||||
|
||||
After that, add the repository to your sources list so that you can easily upgrade the Yarn package in future with the rest of the system updates:
|
||||
|
||||
```
|
||||
sudo sh -c 'echo "deb https://dl.yarnpkg.com/debian/ stable main" >> /etc/apt/sources.list.d/yarn.list'
|
||||
```
|
||||
|
||||
You are set to go now. [Update Ubuntu][7] or Debian system to refresh the list of available packages and then install yarn:
|
||||
|
||||
```
|
||||
sudo apt update
|
||||
sudo apt install yarn
|
||||
```
|
||||
|
||||
This will install Yarn along with nodejs. Once the process completes, verify that Yarn has been installed successfully. You can do that by checking the Yarn version.
|
||||
|
||||
```
|
||||
yarn --version
|
||||
```
|
||||
|
||||
For me, it showed an output like this:
|
||||
|
||||
```
|
||||
yarn --version
|
||||
1.12.3
|
||||
```
|
||||
|
||||
This means that I have Yarn version 1.12.3 installed on my system.
|
||||
|
||||
### Using Yarn
|
||||
|
||||
I presume that you have some basic understandings of JavaScript programming and how dependencies work. I am not going to go in details here. I’ll show you some of the basic Yarn commands that will help you getting started with it.
|
||||
|
||||
#### Creating a new project with Yarn
|
||||
|
||||
Like npm, Yarn also works with a package.json file. This is where you add your dependencies. All the packages of the dependencies are cached in the node_modules directory in the root directory of your project.
|
||||
|
||||
In the root directory of your project, run the following command to generate a fresh package.json file:
|
||||
|
||||
It will ask you a number of questions. You can skip the questions r go with the defaults by pressing enter.
|
||||
|
||||
```
|
||||
yarn init
|
||||
yarn init v1.12.3
|
||||
question name (test_yarn): test_yarn_proect
|
||||
question version (1.0.0): 0.1
|
||||
question description: Test Yarn
|
||||
question entry point (index.js):
|
||||
question repository url:
|
||||
question author: abhishek
|
||||
question license (MIT):
|
||||
question private:
|
||||
success Saved package.json
|
||||
Done in 82.42s.
|
||||
```
|
||||
|
||||
With this, you get a package.json file of this sort:
|
||||
|
||||
```
|
||||
{
|
||||
"name": "test_yarn_proect",
|
||||
"version": "0.1",
|
||||
"description": "Test Yarn",
|
||||
"main": "index.js",
|
||||
"author": "abhishek",
|
||||
"license": "MIT"
|
||||
}
|
||||
```
|
||||
|
||||
Now that you have the package.json, you can either manually edit it to add or remove package dependencies or use Yarn commands (preferred).
|
||||
|
||||
#### Adding dependencies with Yarn
|
||||
|
||||
You can add a dependency on a certain package in the following fashion:
|
||||
|
||||
```
|
||||
yarn add <package_name>
|
||||
```
|
||||
|
||||
For example, if you want to use [Lodash][8] in your project, you can add it using Yarn like this:
|
||||
|
||||
```
|
||||
yarn add lodash
|
||||
yarn add v1.12.3
|
||||
info No lockfile found.
|
||||
[1/4] Resolving packages…
|
||||
[2/4] Fetching packages…
|
||||
[3/4] Linking dependencies…
|
||||
[4/4] Building fresh packages…
|
||||
success Saved lockfile.
|
||||
success Saved 1 new dependency.
|
||||
info Direct dependencies
|
||||
└─ [email protected]
|
||||
info All dependencies
|
||||
└─ [email protected]
|
||||
Done in 2.67s.
|
||||
```
|
||||
|
||||
And you can see that this dependency has been added automatically in the package.json file:
|
||||
|
||||
```
|
||||
{
|
||||
"name": "test_yarn_proect",
|
||||
"version": "0.1",
|
||||
"description": "Test Yarn",
|
||||
"main": "index.js",
|
||||
"author": "abhishek",
|
||||
"license": "MIT",
|
||||
"dependencies": {
|
||||
"lodash": "^4.17.11"
|
||||
}
|
||||
}
|
||||
```
|
||||
|
||||
By default, Yarn will add the latest version of a package in the dependency. If you want to use a specific version, you may specify it while adding.
|
||||
|
||||
As always, you can also update the package.json file manually.
|
||||
|
||||
#### Upgrading dependencies with Yarn
|
||||
|
||||
You can upgrade a particular dependency to its latest version with the following command:
|
||||
|
||||
```
|
||||
yarn upgrade <package_name>
|
||||
```
|
||||
|
||||
It will see if the package in question has a newer version and will update it accordingly.
|
||||
|
||||
You can also change the version of an already added dependency in the following manner:
|
||||
|
||||
You can also upgrade all the dependencies of your project to their latest version with one single command:
|
||||
|
||||
```
|
||||
yarn upgrade
|
||||
```
|
||||
|
||||
It will check the versions of all the dependencies and will update them if there are any newer versions.
|
||||
|
||||
#### Removing dependencies with Yarn
|
||||
|
||||
You can remove a package from the dependencies of your project in this way:
|
||||
|
||||
```
|
||||
yarn remove <package_name>
|
||||
```
|
||||
|
||||
#### Install all project dependencies
|
||||
|
||||
If you made any changes to the project.json file, you should run either
|
||||
|
||||
```
|
||||
yarn
|
||||
```
|
||||
|
||||
or
|
||||
|
||||
```
|
||||
yarn install
|
||||
```
|
||||
|
||||
to install all the dependencies at once.
|
||||
|
||||
### How to remove Yarn from Ubuntu or Debian
|
||||
|
||||
I’ll complete this tutorial by mentioning the steps to remove Yarn from your system if you used the above steps to install it. If you ever realized that you don’t need Yarn anymore, you will be able to remove it.
|
||||
|
||||
Use the following command to remove Yarn and its dependencies.
|
||||
|
||||
```
|
||||
sudo apt purge yarn
|
||||
```
|
||||
|
||||
You should also remove the Yarn repository from the repository list:
|
||||
|
||||
```
|
||||
sudo rm /etc/apt/sources.list.d/yarn.list
|
||||
```
|
||||
|
||||
The optional next step is to remove the GPG key you had added to the trusted keys. But for that, you need to know the key. You can get that using the apt-key command:
|
||||
|
||||
Warning: apt-key output should not be parsed (stdout is not a terminal) pub rsa4096 2016-10-05 [SC] 72EC F46A 56B4 AD39 C907 BBB7 1646 B01B 86E5 0310 uid [ unknown] Yarn Packaging
|
||||
|
||||
Warning: apt-key output should not be parsed (stdout is not a terminal) pub rsa4096 2016-10-05 [SC] 72EC F46A 56B4 AD39 C907 BBB7 1646 B01B 86E5 0310 uid [ unknown] Yarn Packaging yarn@dan.cx sub rsa4096 2016-10-05 [E] sub rsa4096 2019-01-02 [S] [expires: 2020-02-02]
|
||||
|
||||
The key here is the last 8 characters of the GPG key’s fingerprint in the line starting with pub.
|
||||
|
||||
So, in my case, the key is 86E50310 and I’ll remove it using this command:
|
||||
|
||||
```
|
||||
sudo apt-key del 86E50310
|
||||
```
|
||||
|
||||
You’ll see an OK in the output and the GPG key of Yarn package will be removed from the list of GPG keys your system trusts.
|
||||
|
||||
I hope this tutorial helped you to install Yarn on Ubuntu, Debian, Linux Mint, elementary OS etc. I provided some basic Yarn commands to get you started along with complete steps to remove Yarn from your system.
|
||||
|
||||
I hope you liked this tutorial and if you have any questions or suggestions, please feel free to leave a comment below.
|
||||
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://itsfoss.com/install-yarn-ubuntu
|
||||
|
||||
作者：[Abhishek Prakash][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://itsfoss.com/author/abhishek/
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://yarnpkg.com/lang/en/
|
||||
[2]: https://code.fb.com/
|
||||
[3]: https://www.npmjs.com/
|
||||
[4]: https://itsfoss.com/checksum-tools-guide-linux/
|
||||
[5]: https://itsfoss.com/install-nodejs-ubuntu/
|
||||
[6]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2019/01/yarn-js-ubuntu-debian.jpeg?resize=800%2C450&ssl=1
|
||||
[7]: https://itsfoss.com/update-ubuntu/
|
||||
[8]: https://lodash.com/
|
||||
@ -1,150 +0,0 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (Automate testing for website errors with this Python tool)
|
||||
[#]: via: (https://opensource.com/article/20/7/seodeploy)
|
||||
[#]: author: (JR Oakes https://opensource.com/users/jroakes)
|
||||
|
||||
Automate testing for website errors with this Python tool
|
||||
======
|
||||
SEODeploy helps identify SEO problems in a website before they're
|
||||
deployed.
|
||||
![Computer screen with files or windows open][1]
|
||||
|
||||
As a technical search-engine optimizer, I'm often called in to coordinate website migrations, new site launches, analytics implementations, and other areas that affect sites' online visibility and measurement to limit risk. Many companies generate a substantial portion of monthly recurring revenue from users finding their products and services through search engines. Although search engines have gotten good at handling poorly formatted code, things can still go wrong in development that adversely affects how search engines index and display pages for users.
|
||||
|
||||
I've been part of manual processes attempting to mitigate this risk by reviewing staged changes for search engine optimization (SEO)-breaking problems. My team's findings determine whether the project gets the green light (or not) to launch. But this process is often inefficient, can be applied to only a limited number of pages, and has a high likelihood of human error.
|
||||
|
||||
The industry has long sought a usable and trustworthy way to automate this process while still giving developers and search-engine optimizers a meaningful say in what must be tested. This is important because these groups often have competing priorities in development sprints, with search-engine optimizers pushing for changes and developers needing to control regressions and unexpected experiences.
|
||||
|
||||
### Common SEO-breaking problems
|
||||
|
||||
Many websites I work with have tens of thousands of pages. Some have millions. It's daunting to understand how a development change might affect so many pages. In the world of SEO, you can see large, sitewide changes in how Google and other search engines show your pages from very minor and seemingly innocuous changes. It's imperative to have processes in place that catch these types of errors before they make it to production.
|
||||
|
||||
Below are a few examples of problems that I have seen in the last year.
|
||||
|
||||
#### Accidental noindex
|
||||
|
||||
A proprietary third-party SEO monitoring tool we use, [ContentKing][2], found this problem immediately after launch to production. This is a sneaky error because it's not visible in the HTML, rather it is hidden from view in the server response header, yet it can very quickly cause the loss of your search visibility.
|
||||
|
||||
|
||||
```
|
||||
HTTP/1.1 200 OK
|
||||
Date: Tue May 25 2010 21:12:42 GMT
|
||||
[...]
|
||||
X-Robots-Tag: noindex
|
||||
[...]
|
||||
```
|
||||
|
||||
#### Canonical lower-casing
|
||||
|
||||
A change to production mistakenly lower-cased an entire website's [canonical link elements][3]. The change affected nearly 30,000 URLs. Before the update, the URLs were in title case (for instance, `/URL-Path/`). This is a problem because the canonical link element is a hint for Google about a webpage's true canonical URL version. This change caused many URLs to be removed from Google's index and re-indexed at the new uncased location (`/url-path/`). The impact was a loss of 10–15% of traffic and corruption of page metric data over the next few weeks.
|
||||
|
||||
#### Origin server regression
|
||||
|
||||
One website with a complex and novel implementation of React had a mysterious issue with regression of `origin.domain.com` URLs displaying for its origin content-delivery network server. It would intermittently output the origin host instead of the edge host in the site metadata (such as the canonical link element, URLs, and Open Graph links). The problem was found in the raw HTML and the rendered HTML. This impacted search visibility and the quality of shares on social media.
|
||||
|
||||
### Introducing SEODeploy
|
||||
|
||||
SEOs often use diff-testing tools to look at changes between sets of rendered and raw HTML. Diff testing is ideal because it allows certainty that the eye does not. You want to look for differences in how Google renders your page, not how users do. You want to look at what the raw HTML looks like, not the rendered HTML, as these are two separate processing steps for Google.
|
||||
|
||||
This led my colleagues and me to create [SEODeploy][4], a "Python library for automating SEO testing in deployment pipelines." Our mission was:
|
||||
|
||||
> To develop a tool that allowed developers to provide a few to many URL paths, and which allowed those paths to be diff tested on production and staging hosts, looking specifically for unanticipated regressions in SEO-related data.
|
||||
|
||||
SEODeploy's mechanics are simple: Provide a text file containing a newline-delimited set of paths, and the tool runs a series of modules on those paths, comparing production and staging URLs and reporting on any errors or messages (changes) it finds.
|
||||
|
||||
![SEODeploy overview][5]
|
||||
|
||||
(SEODeploy, [CC BY-SA 4.0][6])
|
||||
|
||||
The configuration for the tool and modules is just one YAML file, which can be customized based on anticipated changes.
|
||||
|
||||
![SEODeploy output][7]
|
||||
|
||||
(SEODeploy, [CC BY-SA 4.0][6])
|
||||
|
||||
The initial release includes the following core features and concepts:
|
||||
|
||||
1. **Open source**: We believe deeply in sharing code that can be criticized, improved, extended, shared, and reused.
|
||||
2. **Modular**: There are many different stacks and edge cases in development for the web. The SEODeploy tool is conceptually simple, so modularity is used to control the complexity. We provide two built modules and an example module that outline the basic structure.
|
||||
3. **URL sampling:** Since it is not always feasible or efficient to test every URL, we included a method to randomly sample XML sitemap URLs or URLs monitored by ContentKing.
|
||||
4. **Flexible diff checking**: Web data is messy. The diff checking functionality tries to do a good job of converting this data to messages (changes) no matter the data type it's checking, including ext, arrays (lists), JSON objects (dictionaries), integers, floats, etc.
|
||||
5. **Automated**: A simple command-line interface is used to call the sampling and execution methods to make it easy to incorporate SEODeploy into existing pipelines.
|
||||
|
||||
|
||||
|
||||
### Modules
|
||||
|
||||
While the core functionality is simple, by design, modules are where SEODeploy gains features and complexity. The modules handle the harder task of getting, cleaning, and organizing the data collected from staging and production servers for comparison.
|
||||
|
||||
#### Headless module
|
||||
|
||||
The tool's [Headless module][8] is a nod to anyone who doesn't want to have to pay for a third-party service to get value from the library. It runs any version of Chrome and extracts rendered data from each comparison set of URLs.
|
||||
|
||||
The headless module extracts the following core data for comparison:
|
||||
|
||||
1. SEO content, e.g., titles, headings, links, etc.
|
||||
2. Performance data from the Chrome Timings and Chrome DevTools Protocol (CDP) Performance APIs
|
||||
3. Calculated performance metrics including the Cumulative Layout Shift (CLS), a recently popular [Web Vital][9] released by Google
|
||||
4. Coverage data for CSS and JavaScript from the CDP Coverage API
|
||||
|
||||
|
||||
|
||||
The module includes functionality to handle authentication for staging, network speed presets (for better normalization of comparisons), as well as a method for handling staging-host replacement in staging comparative data. It should be fairly easy for developers to extend this module to collect any other data they want to compare per page.
|
||||
|
||||
#### Other modules
|
||||
|
||||
We created an [example module][10] for any developer who wants to use the framework to create a custom extraction module. Another module integrates with ContentKing. Note that the ContentKing module requires a subscription to ContentKing, while Headless can be run on any machine capable of running Chrome.
|
||||
|
||||
### Problems to solve
|
||||
|
||||
We have [plans][11] to extend and enhance the library but are looking for [feedback][12] from developers on what works and what doesn't meet their needs. A few of the issues and items on our list are:
|
||||
|
||||
1. Dynamic timestamps create false positives for some comparison elements, especially schema.
|
||||
2. Saving test data to a database to enable reviewing historical deployment processes and testing changes against the last staging push.
|
||||
3. Enhancing the scale and speed of the extraction with a cloud infrastructure for rendering.
|
||||
4. Increasing testing coverage from the current 46% to 99%-plus.
|
||||
5. Currently, we rely on [Poetry][13] for dependency management, but we want to publish a PyPl library so it can be installed easily with `pip install`.
|
||||
6. We are looking for more issues and field data on usage.
|
||||
|
||||
|
||||
|
||||
### Get started
|
||||
|
||||
The project is [on GitHub][4], and we have [documentation][14] for most features.
|
||||
|
||||
We hope that you will clone SEODeploy and give it a go. Our goal is to support the open source community with a tool developed by technical search-engine optimizers and validated by developers and engineers. We've seen the time it takes to validate complex staging issues and the business impact minor changes can have across many URLs. We think this library can save time and de-risk the deployment process for development teams.
|
||||
|
||||
If you have questions, issues, or want to contribute, please see the project's [About page][15].
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/20/7/seodeploy
|
||||
|
||||
作者：[JR Oakes][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://opensource.com/users/jroakes
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/browser_screen_windows_files.png?itok=kLTeQUbY (Computer screen with files or windows open)
|
||||
[2]: https://www.contentkingapp.com/
|
||||
[3]: https://en.wikipedia.org/wiki/Canonical_link_element
|
||||
[4]: https://github.com/locomotive-agency/SEODeploy
|
||||
[5]: https://opensource.com/sites/default/files/uploads/seodeploy.png (SEODeploy overview)
|
||||
[6]: https://creativecommons.org/licenses/by-sa/4.0/
|
||||
[7]: https://opensource.com/sites/default/files/uploads/seodeploy_output.png (SEODeploy output)
|
||||
[8]: https://locomotive-agency.github.io/SEODeploy/modules/headless/
|
||||
[9]: https://web.dev/vitals/
|
||||
[10]: https://locomotive-agency.github.io/SEODeploy/modules/creating/
|
||||
[11]: https://locomotive-agency.github.io/SEODeploy/todo/
|
||||
[12]: https://locomotive-agency.github.io/SEODeploy/about/#contact
|
||||
[13]: https://python-poetry.org/
|
||||
[14]: https://locomotive-agency.github.io/SEODeploy/
|
||||
[15]: https://locomotive-agency.github.io/SEODeploy/about/
|
||||
@ -1,229 +0,0 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (MjSeven)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (How to install software with Ansible)
|
||||
[#]: via: (https://opensource.com/article/20/9/install-packages-ansible)
|
||||
[#]: author: (Seth Kenlon https://opensource.com/users/seth)
|
||||
|
||||
How to install software with Ansible
|
||||
======
|
||||
Automate software installations and updates across your devices with
|
||||
Ansible playbooks.
|
||||
![Puzzle pieces coming together to form a computer screen][1]
|
||||
|
||||
Ansible is a popular automation tool used by sysadmins and developers to keep their computer systems in prime condition. As is often the case with extensible frameworks, [Ansible][2] has limited use on its own, with its real power dwelling in its many modules. Ansible modules are, in a way, what commands are to a [Linux][3] computer. They provide solutions to specific problems, and one common task when maintaining computers is keeping all the ones you use updated and consistent.
|
||||
|
||||
I used to use a text list of packages to keep my systems more or less synchronized: I'd list the packages installed on my laptop and then cross-reference that with my desktop, or between one server and another server, making up for any difference manually. Of course, installing and maintaining applications on a Linux machine is a basic task for Ansible, and it means you can list what you want across all computers under your care.
|
||||
|
||||
### Finding the right Ansible module
|
||||
|
||||
The number of Ansible modules can be overwhelming. How do you find the one you need for a given task? In Linux, you might look in your Applications menu or in `/usr/bin` to discover new applications to run. When you're using Ansible, you refer to the [Ansible module index][4].
|
||||
|
||||
The index is listed primarily by category. With a little searching, you're very likely to find a module for whatever you need. For package management, the [Packaging modules][5] section contains a module for nearly any system with a package manager.
|
||||
|
||||
### Writing an Ansible playbook
|
||||
|
||||
To begin, choose the package manager on your local computer. For instance, if you're going to write your Ansible instructions (a "playbook," as it's called in Ansible) on a laptop running Fedora, start with the `dnf` module. If you're writing on Elementary OS, use the `apt` module, and so on. This gets you started with something you can test and verify as you go, and you can expand your work for your other computers later.
|
||||
|
||||
The first step is to create a directory representing your playbook. This isn't strictly necessary, but it's a good idea to establish the habit. Ansible can run with just a configuration file written in YAML, but if you want to expand your playbook later, you can control Ansible by how you lay out your directories and files. For now, just create a directory called `install_packages` or similar:
|
||||
|
||||
|
||||
```
|
||||
`$ mkdir ~/install_packages`
|
||||
```
|
||||
|
||||
The file that serves as the Ansible playbook can be named anything you like, but it's traditional to name it `site.yml`:
|
||||
|
||||
|
||||
```
|
||||
`$ touch ~/install_packages/site.yml`
|
||||
```
|
||||
|
||||
Open `site.yml` in your favorite text editor, and add this:
|
||||
|
||||
|
||||
```
|
||||
\---
|
||||
\- hosts: localhost
|
||||
tasks:
|
||||
- name: install packages
|
||||
become: true
|
||||
become_user: root
|
||||
dnf:
|
||||
state: present
|
||||
name:
|
||||
- tcsh
|
||||
- htop
|
||||
```
|
||||
|
||||
You must adjust the module name you use to match the distribution you're using. In this example, I used `dnf` because I wrote the playbook on Fedora Linux.
|
||||
|
||||
Like with a command in a Linux terminal, knowing _how_ to invoke an Ansible module is half the battle. This playbook example follows the standard playbook format:
|
||||
|
||||
* `hosts` targets a computer or computers. In this case, the computer being targeted is `localhost`, which is the computer you're using right now (as opposed to a remote system you want Ansible to connect with).
|
||||
* `tasks` opens a list of tasks you want to be performed on the hosts.
|
||||
* `name` is a human-friendly title for a task. In this case, I'm using `install packages` because that's what this task is doing.
|
||||
* `become` permits Ansible to change which user is running this task.
|
||||
* `become_user` permits Ansible to become the `root` user to run this task. This is necessary because only the root user can install new applications using `dnf`.
|
||||
* `dnf` is the name of the module, which you discovered from the module index on the Ansible website.
|
||||
|
||||
|
||||
|
||||
The items under the `dnf` item are specific to the `dnf` module. This is where the module documentation is essential. Like a man page for a Linux command, the module documentation tells you what options are available and what kinds of arguments are required.
|
||||
|
||||
![Ansible documentation][6]
|
||||
|
||||
Ansible module documentation (Seth Kenlon, [CC BY-SA 4.0][7])
|
||||
|
||||
Package installation is a relatively simple task and only requires two elements. The `state` option instructs Ansible to check whether or not _some package_ is present on the system, and the `name` option lists which packages to look for. Ansible deals in machine _state_, so module instructions always imply change. Should Ansible scan a system and find a conflict between how a playbook describes a system (in this case, that the commands `tcsh` and `htop` are present) and what the system state actually is (in this example, `tcsh` and `htop` are not present), then Ansible's task is to make whatever changes are necessary for the system to match the playbook. Ansible can make those changes because of the `dnf` (or `apt` or whatever your package manager is) module.
|
||||
|
||||
Each module is likely to have a different set of options, so when you're writing playbooks, anticipate referring to the module documentation often. Until you're very familiar with a module, it's the only reasonable way to expect a module to do what you need it to do.
|
||||
|
||||
### Verifying YAML
|
||||
|
||||
Playbooks are written in YAML. Because YAML adheres to a strict syntax, it's helpful to install the `yamllint` command to check (or "lint," in computer terminology) your work. Better still, there's a linter specific to Ansible called `ansible-lint` created specifically for playbooks. Install these before continuing.
|
||||
|
||||
On Fedora or CentOS:
|
||||
|
||||
|
||||
```
|
||||
`$ sudo dnf install yamllint python3-ansible-lint`
|
||||
```
|
||||
|
||||
On Debian, Elementary, Ubuntu, or similar:
|
||||
|
||||
|
||||
```
|
||||
`$ sudo apt install yamllint ansible-lint`
|
||||
```
|
||||
|
||||
Verify your playbook with `ansible-lint`. If you don't have access to `ansible-lint`, you can use `yamllint`.
|
||||
|
||||
|
||||
```
|
||||
`$ ansible-lint ~/install_packages/site.yml`
|
||||
```
|
||||
|
||||
Success returns nothing, but if there are errors in your file, you must fix them before continuing. Common errors from copying and pasting include omitting a newline character at the end of the final line and using tabs instead of spaces for indentation. Fix them in a text editor, rerun the linter, and repeat this process until you get no feedback from `ansible-lint` or `yamllint`.
|
||||
|
||||
### Installing an application with Ansible
|
||||
|
||||
Now that you have a verifiably valid playbook, you can finally run it on your local machine. Because you happen to know that the task defined by the playbook requires root permissions, you must use the `--ask-become-pass` option when invoking Ansible, so you will be prompted for your administrative password.
|
||||
|
||||
Start the installation:
|
||||
|
||||
|
||||
```
|
||||
$ ansible-playbook --ask-become-pass ~/install_packages/site.yml
|
||||
BECOME password:
|
||||
PLAY [localhost] ******************************
|
||||
|
||||
TASK [Gathering Facts] ******************************
|
||||
ok: [localhost]
|
||||
|
||||
TASK [install packages] ******************************
|
||||
ok: [localhost]
|
||||
|
||||
PLAY RECAP ******************************
|
||||
localhost: ok=0 changed=2 unreachable=0 failed=0 [...]
|
||||
```
|
||||
|
||||
The commands are installed, leaving the target system in an identical state to the one described by the playbook.
|
||||
|
||||
### Installing an application on remote systems
|
||||
|
||||
Going through all of that to replace one simple command would be counterproductive, but Ansible's advantage is that it can be automated across all of your systems. You can use conditional statements to cause Ansible to use a specific module on different systems, but for now, assume all your computers use the same package manager.
|
||||
|
||||
To connect to a remote system, you must define the remote system in the `/etc/ansible/hosts` file. This file was installed along with Ansible, so it already exists, but it's probably empty, aside from explanatory comments. Use `sudo` to open the file in your favorite text editor.
|
||||
|
||||
You can define a host by its IP address or hostname, as long as the hostname can be resolved. For instance, if you've already defined `liavara` in `/etc/hosts` and can successfully ping it, then you can set `liavara` as a host in `/etc/ansible/hosts`. Alternately, if you're running a domain name server or Avahi server and can ping `liavara`, then you can set it as a host in `/etc/ansible/hosts`. Otherwise, you must use its internet protocol address.
|
||||
|
||||
You also must have set up a successful secure shell (SSH) connection to your target hosts. The easiest way to do that is with the `ssh-copy-id` command, but if you've never set up an SSH connection with a host before, [read my article on how to create an automated SSH connection][8].
|
||||
|
||||
Once you've entered the hostname or IP address in the `/etc/ansible/hosts` file, change the `hosts` definition in your playbook:
|
||||
|
||||
|
||||
```
|
||||
\---
|
||||
\- hosts: all
|
||||
tasks:
|
||||
- name: install packages
|
||||
become: true
|
||||
become_user: root
|
||||
dnf:
|
||||
state: present
|
||||
name:
|
||||
- tcsh
|
||||
- htop
|
||||
```
|
||||
|
||||
Run `ansible-playbook` again:
|
||||
|
||||
|
||||
```
|
||||
`$ ansible-playbook --ask-become-pass ~/install_packages/site.yml`
|
||||
```
|
||||
|
||||
This time, the playbook runs on your remote system.
|
||||
|
||||
Should you add more hosts, there are many ways to filter which host performs which task. For instance, you can create groups of hosts (`webservers` for servers, `workstations` for desktop machines, and so on).
|
||||
|
||||
### Ansible for mixed environments
|
||||
|
||||
The logic used in the solution so far assumes that all hosts being configured by Ansible run the same OS (specifically, one that uses the **dnf** command for package management). So what do you do if you're managing hosts running a different distribution, such as Ubuntu (which uses **apt**) or Arch (using **pacman**), or even different operating systems?
|
||||
|
||||
As long as the targeted OS has a package manager (and these days even [MacOS has Homebrew][9] and [Windows has Chocolatey][10]), Ansible can help.
|
||||
|
||||
This is where Ansible's advantage becomes most apparent. In a shell script, you'd have to check for what package manager is available on the target host, and even with pure Python you'd have to check for the OS. Ansible not only has those checks built in, but it also has mechanisms to use the results in your playbook. Instead of using the **dnf** module, you can use the **action** keyword to perform tasks defined by variables provided by Ansible's fact gathering subsystem.
|
||||
|
||||
|
||||
```
|
||||
\---
|
||||
\- hosts: all
|
||||
tasks:
|
||||
- name: install packages
|
||||
become: true
|
||||
become_user: root
|
||||
action: >
|
||||
{{ ansible_pkg_mgr }} name=htop,transmission state=present update_cache=yes
|
||||
```
|
||||
|
||||
The **action** keyword loads action plugins. In this example, it's using the **ansible_pkg_mgr** variable, which is populated by Ansible during the initial **Gathering Facts** task. You don't have to tell Ansible to gather facts about the OS it's running on, so it's easy to overlook it, but when you run a playbook, you see it listed in the default output:
|
||||
|
||||
|
||||
```
|
||||
TASK [Gathering Facts] *****************************************
|
||||
ok: [localhost]
|
||||
```
|
||||
|
||||
The **action** plugin uses information from this probe to populate **ansible_pkg_mgr** with the relevant package manager command to install the packages listed after the **name** argument. With 8 lines of code, you can overcome a complex cross-platform quandary that few other scripting options allow.
|
||||
|
||||
### Use Ansible
|
||||
|
||||
It's the 21st century, and we all expect our computing devices to be connected and relatively consistent. Whether you maintain two or 200 computers, you shouldn't have to perform the same maintenance tasks over and over again. Use Ansible to synchronize the computers in your life, then see what else Ansible can do for you.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/20/9/install-packages-ansible
|
||||
|
||||
作者：[Seth Kenlon][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://opensource.com/users/seth
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/puzzle_computer_solve_fix_tool.png?itok=U0pH1uwj (Puzzle pieces coming together to form a computer screen)
|
||||
[2]: https://opensource.com/resources/what-ansible
|
||||
[3]: https://opensource.com/resources/linux
|
||||
[4]: https://docs.ansible.com/ansible/latest/modules/modules_by_category.html
|
||||
[5]: https://docs.ansible.com/ansible/latest/modules/list_of_packaging_modules.html
|
||||
[6]: https://opensource.com/sites/default/files/uploads/ansible-module.png (Ansible documentation)
|
||||
[7]: https://creativecommons.org/licenses/by-sa/4.0/
|
||||
[8]: https://opensource.com/article/20/8/how-ssh
|
||||
[9]: https://opensource.com/article/20/6/homebrew-mac
|
||||
[10]: https://opensource.com/article/20/3/chocolatey
|
||||
@ -1,89 +0,0 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (geekpi)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (How to Use the Firefox Task Manager (to Find and Kill RAM and CPU Eating Tabs and Extensions))
|
||||
[#]: via: (https://itsfoss.com/firefox-task-manager/)
|
||||
[#]: author: (Ankush Das https://itsfoss.com/author/ankush/)
|
||||
|
||||
How to Use the Firefox Task Manager (to Find and Kill RAM and CPU Eating Tabs and Extensions)
|
||||
======
|
||||
|
||||
Firefox is popular among Linux users. It is the default web browser on several Linux distributions.
|
||||
|
||||
Among many other features, Firefox provides a task manager of its own.
|
||||
|
||||
Now, why would you use it when you have [task manager in Linux][1] in the form of [system monitoring tools][2]? There is a good reason for that.
|
||||
|
||||
Suppose your system is taking too much of RAM or CPU. If you use top or some other system [resource monitoring tool like Glances][3], you’ll notice that these tools cannot distinguish the opened tabs or extensions.
|
||||
|
||||
Usually, each Firefox tab is displayed as **Web Content**. You can see that some Firefox process is causing the issue but that’s no way to accurately determine which tab or extension it is.
|
||||
|
||||
This is where you can use the Firefox task manager. Let me show you how!
|
||||
|
||||
### Firefox Task Manager
|
||||
|
||||
With Firefox Task Manager, you will be able to list all the tabs, trackers, and add-ons consuming system resources.
|
||||
|
||||
![][4]
|
||||
|
||||
As you can see in the screenshot above, you get the name of the tab, the type (tab or add-on), the energy impact, and the memory consumed.
|
||||
|
||||
While everything is self-explanatory, the **energy impact refers to the CPU usage** and if you are using a Laptop, it is a good indicator to show you what will drain the battery quicker.
|
||||
|
||||
#### Access Task Manager in Firefox
|
||||
|
||||
Surprisingly, there is no [Firefox keyboard shortcut][5] for the task manager.
|
||||
|
||||
To quickly launch Firefox Task Manager, you can type “**about:performance**” in the address bar as shown in the screenshot below.
|
||||
|
||||
![Quickly access task manager in Firefox][6]
|
||||
|
||||
Alternatively, you can click on the **menu** icon and then head on to “**More**” options as shown in the screenshot below.
|
||||
|
||||
![Accessing task manager in Firefox][7]
|
||||
|
||||
Next, you will find the option to select “**Task Manager**” — so just click on it.
|
||||
|
||||
![][8]
|
||||
|
||||
#### Using Firefox task manager
|
||||
|
||||
Once there, you can check for the resource usage, expand the tabs to see the trackers and its usage, and also choose to close the tabs right there as highlighted in the screenshot below.
|
||||
|
||||
![][9]
|
||||
|
||||
Here’s what you should know:
|
||||
|
||||
* Energy impact means CPU consumption.
|
||||
* The subframes or the subtasks are usually the trackers/scripts associated with a tab that needs to run in the background.
|
||||
|
||||
|
||||
|
||||
With this task manager, you can spot a rogue script on a site as well whether it’s causing your browser to slow down.
|
||||
|
||||
This isn’t rocket-science but not many people are aware of Firefox task manager. Now that you know it, this should come in pretty handy, don’t you think?
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://itsfoss.com/firefox-task-manager/
|
||||
|
||||
作者：[Ankush Das][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://itsfoss.com/author/ankush/
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://itsfoss.com/task-manager-linux/
|
||||
[2]: https://itsfoss.com/linux-system-monitoring-tools/
|
||||
[3]: https://itsfoss.com/glances/
|
||||
[4]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2020/09/firefox-task-manager-shot.png?resize=800%2C519&ssl=1
|
||||
[5]: https://itsfoss.com/firefox-keyboard-shortcuts/
|
||||
[6]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2020/09/firefox-url-performance.jpg?resize=800%2C357&ssl=1
|
||||
[7]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2020/09/firefox-task-manager-steps.jpg?resize=800%2C779&ssl=1
|
||||
[8]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2020/09/firefox-task-manager-menu.jpg?resize=800%2C465&ssl=1
|
||||
[9]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2020/09/firefox-task-manager-close-tab.png?resize=800%2C496&ssl=1
|
||||
@ -1,119 +0,0 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (geekpi)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (Drawing is an Open Source MS-Paint Type of App for Linux Desktop)
|
||||
[#]: via: (https://itsfoss.com/drawing-app/)
|
||||
[#]: author: (Abhishek Prakash https://itsfoss.com/author/abhishek/)
|
||||
|
||||
Drawing is an Open Source MS-Paint Type of App for Linux Desktop
|
||||
======
|
||||
|
||||
_**Brief: Drawing is a basic image editor like Microsoft Paint. With this open source application, you can draw arrows, lines, geometrical shapes, add colors and other stuff you expect to do in a regular drawing application.**_
|
||||
|
||||
### Drawing: A simple drawing application for Linux
|
||||
|
||||
![][1]
|
||||
|
||||
For people introduced to computers with Windows XP (or earlier version), MS Paint was an amusing application from sketching random stuff. In a world dominated with Photoshop and GIMP, the paint applications still hold some relevance.
|
||||
|
||||
There are several [painting applications available for Linux][2], and I am going to add one more to this list.
|
||||
|
||||
The app is unsurprisingly called [Drawing][3] and you can use it on both Linux desktop and Linux smartphones.
|
||||
|
||||
### Features of Drawing app
|
||||
|
||||
![][4]
|
||||
|
||||
Drawing has all the features you expect from a drawing application. You can
|
||||
|
||||
* Create new drawings from scratch
|
||||
* Edit an existing image in PNG, JPEG or BMP file
|
||||
* Add geometrical shapes, lines, arrows etc
|
||||
* Dashed
|
||||
* Use pencil tool for free-hand drawing
|
||||
* Use curve and shape tool
|
||||
* Crop images
|
||||
* Scale images to different pixel size
|
||||
* Add text
|
||||
* Select part of image (rectangle, freehand and color selection)
|
||||
* Rotate images
|
||||
* Add images copied to clipboard
|
||||
* Eraser, Highlighter, Paint, Color Selection, Color Picker tools are available in preferences
|
||||
* Unlimited undo
|
||||
* Filters to add blur, pixelisation, transparency etc
|
||||
|
||||
|
||||
|
||||
### My experience with Drawing
|
||||
|
||||
![][5]
|
||||
|
||||
The application is new and has a decent user interface. It comes with all the basic features you expect to find in a standard paint app.
|
||||
|
||||
It has some additional tools like color selection and color picker but it might be confusing to use them. There is no documentation available to describe the use of these tools to you are on your own here.
|
||||
|
||||
The experience is smooth and I feel that this tool has good potential to replace Shutter as image editing tool (yes, I [use Shutter for editing screenshots][6]).
|
||||
|
||||
The thing that I find most bothersome is that it is not possible to edit/modify an element after adding it. You have the undo and redo options but if you want to modify a text you added 12 steps back, you’ll have to redo all the steps. This is something the developer may look into it in the future releases.
|
||||
|
||||
### Installing Drawing on Linux
|
||||
|
||||
This is a Linux exclusive app. It is also available for Linux-based smartphones like [PinePhone][7].
|
||||
|
||||
There are various ways you can install Drawing app. It is available in the repositories of many major Linux distributions.
|
||||
|
||||
#### Ubuntu-based distributions
|
||||
|
||||
Drawing is included in the universe repository in Ubuntu. Which means you can install it from the Ubuntu Software Center.
|
||||
|
||||
However, if you want the latest version, there is a [PPA available][8] for easily installing Drawing on Ubuntu. Linux Mint and other Ubuntu-based distributions.
|
||||
|
||||
Use the following command:
|
||||
|
||||
```
|
||||
sudo add-apt-repository ppa:cartes/drawing
|
||||
sudo apt update
|
||||
sudo apt install drawing
|
||||
```
|
||||
|
||||
If you want to remove it, you can use the following commands:
|
||||
|
||||
```
|
||||
sudo apt remove drawing
|
||||
sudo add-apt-repository -r ppa:cartes/drawing
|
||||
```
|
||||
|
||||
#### Other Linux distributions
|
||||
|
||||
Check your distribution’s package manager for Drawing and install it from there. If you want the latest version, you may use the Flatpak version of the app.
|
||||
|
||||
[Drawing Flatpak][9]
|
||||
|
||||
**Conclusion**
|
||||
|
||||
Do you still use a paint application? Which one do you use? If you have tried Drawing app already, how is your experience with it?
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://itsfoss.com/drawing-app/
|
||||
|
||||
作者：[Abhishek Prakash][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://itsfoss.com/author/abhishek/
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2020/09/drawing-app-interface.jpg?resize=789%2C449&ssl=1
|
||||
[2]: https://itsfoss.com/open-source-paint-apps/
|
||||
[3]: https://maoschanz.github.io/drawing/
|
||||
[4]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2020/09/drawing-screenshot.jpg?resize=800%2C489&ssl=1
|
||||
[5]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2020/09/using-drawing-app-linux.png?resize=787%2C473&ssl=1
|
||||
[6]: https://itsfoss.com/install-shutter-ubuntu/
|
||||
[7]: https://itsfoss.com/pinephone/
|
||||
[8]: https://launchpad.net/~cartes/+archive/ubuntu/drawing
|
||||
[9]: https://flathub.org/apps/details/com.github.maoschanz.drawing
|
||||
@ -1,5 +1,5 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: translator: (geekpi)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
|
||||
113
sources/tech/20201005 How the Linux kernel handles interrupts.md
Normal file
113
sources/tech/20201005 How the Linux kernel handles interrupts.md
Normal file
@ -0,0 +1,113 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (How the Linux kernel handles interrupts)
|
||||
[#]: via: (https://opensource.com/article/20/10/linux-kernel-interrupts)
|
||||
[#]: author: (Stephan Avenwedde https://opensource.com/users/hansic99)
|
||||
|
||||
How the Linux kernel handles interrupts
|
||||
======
|
||||
Interrupts are a crucial part of how computers process data.
|
||||
![Penguin driving a car with a yellow background][1]
|
||||
|
||||
Interrupts are an essential part of how modern CPUs work. For example, every time you press a key on the keyboard, the CPU is interrupted so that the PC can read user input from the keyboard. This happens so quickly that you don't notice any change or impairment in user experience.
|
||||
|
||||
Moreover, the keyboard is not the only component that can cause interrupts. In general, there are three types of events that can cause the CPU to interrupt: _Hardware interrupts_, _software interrupts_, and _exceptions_. Before getting into the different types of interrupts, I'll define some terms.
|
||||
|
||||
### Definitions
|
||||
|
||||
An interrupt request (**IRQ**) is requested by the programmable interrupt controller (**PIC**) with the aim of interrupting the CPU and executing the interrupt service routine (**ISR**). The ISR is a small program that processes certain data depending on the cause of the IRQ. Normal processing is interrupted until the ISR finishes.
|
||||
|
||||
In the past, IRQs were handled by a separate microchip—the PIC—and I/O devices were wired directly to the PIC. The PIC managed the various hardware IRQs and could talk directly to the CPU. When an IRQ occurred, the PIC wrote the data to the CPU and raised the interrupt request (**INTR**) pin.
|
||||
|
||||
Nowadays, IRQs are handled by an advanced programmable interrupt controller (**APIC**), which is part of the CPU. Each core has its own APIC.
|
||||
|
||||
### Types of interrupts
|
||||
|
||||
As I mentioned, interrupts can be separated into three types depending on their source:
|
||||
|
||||
#### Hardware interrupts
|
||||
|
||||
When a hardware device wants to tell the CPU that certain data is ready to process (e.g., a keyboard entry or when a packet arrives at the network interface), it sends an IRQ to signal the CPU that the data is available. This invokes a specific ISR that was registered by the device driver during the kernel's start.
|
||||
|
||||
#### Software interrupts
|
||||
|
||||
When you're playing a video, it is essential to synchronize the music and video playback so that the music's speed doesn't vary. This is accomplished through a software interrupt that is repetitively fired by a precise timer system (known as [jiffies][2]). This timer enables your music player to synchronize. A software interrupt can also be invoked by a special instruction to read or write data to a hardware device.
|
||||
|
||||
Software interrupts are also crucial when real-time capability is required (such as in industrial applications). You can find more information about this in the Linux Foundation's article _[Intro to real-time Linux for embedded developers][3]_.
|
||||
|
||||
#### Exceptions
|
||||
|
||||
Exceptions are the type of interrupt that you probably know about. When the CPU executes a command that would result in division by zero or a page fault, any additional execution is interrupted. In such a case, you will be informed about it by a pop-up window or by seeing **segmentation fault (core dumped)** in the console output. But not every exception is caused by a faulty instruction.
|
||||
|
||||
Exceptions can be further divided into _Faults_, _Traps_, and _Aborts_.
|
||||
|
||||
* **Faults:** Faults are an exception that the system can correct, e.g., when a process tries to access data from a memory page that was swapped to the hard drive. The requested address is within the process address space, and the access rights are correct. If the page is not present in RAM, an IRQ is raised and it starts the **page fault exception handler** to load the desired memory page into RAM. If the operation is successful, execution will continue.
|
||||
* **Traps:** Traps are mainly used for debugging. If you set a breakpoint in a program, you insert a special instruction that causes it to trigger a trap. A trap can trigger a context switch that allows your debugger to read and display values of local variables. Execution can continue afterward. Traps are also the default way to execute system calls (like killing a process).
|
||||
* **Aborts:** Aborts are caused by hardware failure or inconsistent values in system tables. An abort does not report the location of the instruction that causes the exception. These are the most critical interrupts. An abort invokes the system's **abort exception handler**, which terminates the process that caused it.
|
||||
|
||||
|
||||
|
||||
### Get hands-on
|
||||
|
||||
IRQs are ordered by priority in a vector on the APIC (0=highest priority). The first 32 interrupts (0–31) have a fixed sequence that is specified by the CPU. You can find an overview of them on [OsDev's Exceptions][4] page. Subsequent IRQs can be assigned differently. The interrupt descriptor table (**IDT**) contains the assignment between IRQ and ISR. Linux defines an IRQ vector from 0 to 256 for the assignment.
|
||||
|
||||
To print a list of registered interrupts on your system, open a console and type:
|
||||
|
||||
|
||||
```
|
||||
`cat /proc/interrupts`
|
||||
```
|
||||
|
||||
You should see something like this:
|
||||
|
||||
![Registered interrupts list][5]
|
||||
|
||||
Registered interrupts in kernel version 5.6.6 (Stephan Avenwedde, [CC BY-SA 4.0][6])
|
||||
|
||||
From left to right, the columns are: IRQ vector, interrupt count per CPU (`0 .. n`), the hardware source, the hardware source's channel information, and the name of the device that caused the IRQ.
|
||||
|
||||
On the bottom of the table, there are some non-numeric interrupts. They are the architecture-specific interrupts, like the local timer interrupt (**LOC**) on IRQ 236. Some of them are specified in the [Linux IRQ vector layout][7] in the Linux kernel source tree.
|
||||
|
||||
![Architecture-specific interrupts][8]
|
||||
|
||||
Architecture-specific interrupts (Stephan Avenwedde, [CC BY-SA 4.0][6])
|
||||
|
||||
To get a live view of this table, run:
|
||||
|
||||
|
||||
```
|
||||
`watch -n1 "cat /proc/interrupts"`
|
||||
```
|
||||
|
||||
### Conclusion
|
||||
|
||||
Proper IRQ handling is essential for the proper interaction of hardware, drivers, and software. Luckily, the Linux kernel does a really good job, and a normal PC user will hardly notice anything about the kernel's entire interrupt handling.
|
||||
|
||||
This can get very complicated, and this article gives only a brief overview of the topic. Good sources of information for a deeper dive into the subject are the _[Linux Inside][9]_ eBook (CC BY-NC-SA 4.0) and the [Linux Kernel Teaching][10] repository.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/20/10/linux-kernel-interrupts
|
||||
|
||||
作者：[Stephan Avenwedde][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://opensource.com/users/hansic99
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/car-penguin-drive-linux-yellow.png?itok=twWGlYAc (Penguin driving a car with a yellow background)
|
||||
[2]: https://elinux.org/Kernel_Timer_Systems
|
||||
[3]: https://www.linuxfoundation.org/blog/2013/03/intro-to-real-time-linux-for-embedded-developers/
|
||||
[4]: https://wiki.osdev.org/Exceptions
|
||||
[5]: https://opensource.com/sites/default/files/uploads/proc_interrupts_1.png (Registered interrupts list)
|
||||
[6]: https://creativecommons.org/licenses/by-sa/4.0/
|
||||
[7]: https://github.com/torvalds/linux/blob/master/arch/x86/include/asm/irq_vectors.h
|
||||
[8]: https://opensource.com/sites/default/files/uploads/proc_interrupts_2.png (Architecture-specific interrupts)
|
||||
[9]: https://0xax.gitbooks.io/linux-insides/content/Interrupts/
|
||||
[10]: https://linux-kernel-labs.github.io/refs/heads/master/lectures/interrupts.html#
|
||||
@ -0,0 +1,110 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (Linux Jargon Buster: What is a Package Manager in Linux? How Does it Work?)
|
||||
[#]: via: (https://itsfoss.com/package-manager/)
|
||||
[#]: author: (Abhishek Prakash https://itsfoss.com/author/abhishek/)
|
||||
|
||||
Linux Jargon Buster: What is a Package Manager in Linux? How Does it Work?
|
||||
======
|
||||
|
||||
One of the main points [how Linux distributions differ from each other][1] is the package management. In this part of the Linux jargon buster series, you’ll learn about packaging and package managers in Linux. You’ll learn what are packages, what are package managers and how do they work and what kind of package managers available.
|
||||
|
||||
### What is a package manager in Linux?
|
||||
|
||||
In simpler words, a package manager is a tool that allows users to install, remove, upgrade, configure and manage software packages on an operating system. The package manager can be a graphical application like a software center or a command line tool like [apt-get][2] or [pacman][3].
|
||||
|
||||
You’ll often find me using the term ‘package’ in tutorials and articles on It’s FOSS. To understand package manager, you must understand what a package is.
|
||||
|
||||
### What is a package?
|
||||
|
||||
A package is usually referred to an application but it could be a GUI application, command line tool or a software library (required by other software programs). A package is essentially an archive file containing the binary executable, configuration file and sometimes information about the dependencies.
|
||||
|
||||
In older days, [software used to installed from its source code][4]. You would refer to a file (usually named readme) and see what software components it needs, location of binaries. A configure script or makefile is often included. You will have to compile the software or on your own along with handling all the dependencies (some software require installation of other software) on your own.
|
||||
|
||||
To get rid of this complexity, Linux distributions created their own packaging format to provide the end users ready-to-use binary files (precompiled software) for installing software along with some [metadata][5] (version number, description) and dependencies.
|
||||
|
||||
It is like baking a cake versus buying a cake.
|
||||
|
||||
![][6]
|
||||
|
||||
Around mid 90s, Debian created .deb or DEB packaging format and Red Hat Linux created .rpm or RPM (short for Red Hat Package Manager) packaging system. Compiling source code still exists but it is optional now.
|
||||
|
||||
To interact with or use the packaging systems, you need a package manager.
|
||||
|
||||
### How does the package manager work?
|
||||
|
||||
Please keep in mind that package manager is a generic concept and it’s not exclusive to Linux. You’ll often find package manager for different software or programming languages. There is [PIP package manager just for Python packages][7]. Even [Atom editor has its own package manager][8].
|
||||
|
||||
Since the focus in this article is on Linux, I’ll take things from Linux’s perspective. However, most of the explanation here could be applied to package manager in general as well.
|
||||
|
||||
I have created this diagram (based on SUSE Wiki) so that you can easily understand how a package manager works.
|
||||
|
||||
![][9]
|
||||
|
||||
Almost all Linux distributions have software repositories which is basically collection of software packages. Yes, there could be more than one repository. The repositories contain software packages of different kind.
|
||||
|
||||
Repositories also have metadata files that contain information about the packages such as the name of the package, version number, description of package and the repository name etc. This is what you see if you use the [apt show command][10] in Ubuntu/Debian.
|
||||
|
||||
Your system’s package manager first interacts with the metadata. The package manager creates a local cache of metadata on your system. When you run the update option of the package manager (for example apt update), it updates this local cache of metadata by referring to metadata from the repository.
|
||||
|
||||
When you run the installation command of your package manager (for example apt install package_name), the package manager refers to this cache. If it finds the package information in the cache, it uses the internet connection to connect to the appropriate repository and downloads the package first before installing on your system.
|
||||
|
||||
A package may have dependencies. Meaning that it may require other packages to be installed. The package manager often takes care of the dependencies and installs it automatically along with the package you are installing.
|
||||
|
||||
![Package Manager Handling Dependencies In Linux][11]
|
||||
|
||||
Similarly, when you remove a package using the package manager, it either automatically removes or informs you that your system has unused packages that can be cleaned.
|
||||
|
||||
Apart from the obvious tasks of installing, removing, you can use the package manager to configure the packages and manage them as per your need. For example, you can [prevent the upgrade of a package version][12] from the regular system updates. There are many more things your package manager might be capable of.
|
||||
|
||||
### Different kinds of package managers
|
||||
|
||||
Package Managers differ based on packaging system but same packaging system may have more than one package manager.
|
||||
|
||||
For example, RPM has [Yum][13] and [DNF][14] package managers. For DEB, you have apt-get, [aptitude][15] command line based package managers.
|
||||
|
||||
![Synaptic package manager][16]
|
||||
|
||||
Package managers are not necessarily command line based. You have graphical package managing tools like [Synaptic][17]. Your distribution’s software center is also a package manager even if it runs apt-get or DNF underneath.
|
||||
|
||||
### Conclusion
|
||||
|
||||
I don’t want to go in further detail on this topic because I can go on and on. But it will deviate from the objective of the topic which is to give you a basic understanding of package manager in Linux.
|
||||
|
||||
I have omitted the new universal packaging formats like Snap and Flatpak for now.
|
||||
|
||||
I do hope that you have a bit better understanding of the package management system in Linux. If you are still confused or if you have some questions on this topic, please use the comment system. I’ll try to answer your questions and if required, update this article with new points.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://itsfoss.com/package-manager/
|
||||
|
||||
作者：[Abhishek Prakash][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://itsfoss.com/author/abhishek/
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://itsfoss.com/what-is-linux/
|
||||
[2]: https://itsfoss.com/apt-vs-apt-get-difference/
|
||||
[3]: https://itsfoss.com/pacman-command/
|
||||
[4]: https://itsfoss.com/install-software-from-source-code/
|
||||
[5]: https://www.computerhope.com/jargon/m/metadata.htm
|
||||
[6]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2020/10/source-code-comilation-vs-packaging.png?resize=800%2C450&ssl=1
|
||||
[7]: https://itsfoss.com/install-pip-ubuntu/
|
||||
[8]: https://itsfoss.com/install-packages-in-atom/
|
||||
[9]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2020/10/linux-package-manager-explanation.png?resize=800%2C450&ssl=1
|
||||
[10]: https://itsfoss.com/apt-search-command/
|
||||
[11]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2020/10/package-manager-handling-dependencies-in-linux.png?resize=800%2C450&ssl=1
|
||||
[12]: https://itsfoss.com/prevent-package-update-ubuntu/
|
||||
[13]: https://fedoraproject.org/wiki/Yum
|
||||
[14]: https://fedoraproject.org/wiki/DNF
|
||||
[15]: https://wiki.debian.org/Aptitude
|
||||
[16]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2020/06/see-packages-by-repositories-synaptic.png?resize=799%2C548&ssl=1
|
||||
[17]: https://itsfoss.com/synaptic-package-manager/
|
||||
@ -0,0 +1,165 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (5 Scratch code blocks to teach kids how to program a video game)
|
||||
[#]: via: (https://opensource.com/article/20/10/advanced-scratch)
|
||||
[#]: author: (Jess Weichler https://opensource.com/users/cyanide-cupcake)
|
||||
|
||||
5 Scratch code blocks to teach kids how to program a video game
|
||||
======
|
||||
Advance your Scratch skills with loops, conditional statements,
|
||||
collision detection, and more in this article in a series about teaching
|
||||
kids to code.
|
||||
![Binary code on a computer screen][1]
|
||||
|
||||
In the second article in this series, you [created your first few video game scripts in Scratch][2]. This article explores ways to expand programming's possibilities to create more advanced code.
|
||||
|
||||
There are multiple ways to introduce these skills to kids, such as:
|
||||
|
||||
1. Introduce a task or challenge that requires children to use the skill. Use inquiry to help them find the solution, then reinforce their discoveries with a formal explanation.
|
||||
2. Encourage free experimentation by having children come up with their own projects. As they work through their code, go over skills as needed.
|
||||
3. Introduce the skill, then have children experiment with it.
|
||||
|
||||
|
||||
|
||||
No matter which one you choose, always remember that the most important part of learning coding is making mistakes. Even skilled programmers don't get it right every time or know every possible line of code. It works best when educators, pupils, and peers are all learning to code together as a team.
|
||||
|
||||
There are [10 categories][3] of code blocks in Scratch; here is how to use some of the most common.
|
||||
|
||||
### Loops
|
||||
|
||||
_This is the code that doesn't end; yes, it goes on and on, my friend!_ **Forever loops** and **repeat blocks** in [Scratch][4] are what you need to repeat lines of code automatically. Any code blocks placed inside a loop block continue to run until the game is stopped or, if you're using a repeat block, the number is reached.
|
||||
|
||||
![Loops in Scratch][5]
|
||||
|
||||
(Jess Weichler, [CC BY-SA 4.0][6])
|
||||
|
||||
### Conditional statements
|
||||
|
||||
**Conditional statements** run only if certain conditions are met. "If you're cold, then put on a sweater" is a real-world example of a conditional statement: you put a sweater on only if you determine that it's cold.
|
||||
|
||||
There are four conditional statement code blocks in Scratch:
|
||||
|
||||
* if ... then
|
||||
* if ... then ... else
|
||||
* wait until...
|
||||
* repeat until...
|
||||
|
||||
|
||||
|
||||
Any code blocks placed inside a conditional statement run only if the condition is met.
|
||||
|
||||
![Conditional statement blocks in Scratch][7]
|
||||
|
||||
(Jess Weichler, [CC BY-SA 4.0][6])
|
||||
|
||||
Notice the diamond shapes in each conditional statement code block; can you find any code blocks that might fit inside?
|
||||
|
||||
Diamond-shaped code blocks can be used to complete any of the four conditional-statement blocks. You can find diamond-shaped blocks in the [Sensing][8] and [Operators][9] block categories.
|
||||
|
||||
![Diamond-shaped blocks in Scratch][10]
|
||||
|
||||
(Jess Weichler, [CC BY-SA 4.0][6])
|
||||
|
||||
### Collision-detection loop
|
||||
|
||||
Sometimes you may want to check to see if your sprite is touching another sprite or a specific color. To do so, use a [**collision-detection loop**][11].
|
||||
|
||||
A collision-detection loop combines loops and conditional statements to constantly check whether the sprite is touching another sprite (for example, a coin sprite).
|
||||
|
||||
![Collision-detection script in Scratch][12]
|
||||
|
||||
(Jess Weichler, [CC BY-SA 4.0][6])
|
||||
|
||||
Inside the inner `if ... then` block, place the action you want to happen when the condition is met.
|
||||
|
||||
This type of algorithm is a **collision-detection script**. Collision-detection scripts sense when two sprites or objects are touching. A basic collision-detection script uses four main code blocks:
|
||||
|
||||
* Event hat
|
||||
* Forever loop
|
||||
* If … then
|
||||
* Touching
|
||||
|
||||
|
||||
|
||||
You can place more code blocks inside the `if ... then` block. These blocks will run only if the active sprite is touching the sprite listed in the `touching` block.
|
||||
|
||||
Can you figure out how to make an object "hide" when it collides with another sprite? This is a common technique to indicate that, for instance, a sprite has eaten some food or has picked up an item.
|
||||
|
||||
### Variables and math
|
||||
|
||||
A **variable** is a placeholder for a value, usually a number, that you don't know yet. In math, using a variable might look something like this: `x+12=15`.
|
||||
|
||||
![Variables in Scratch][13]
|
||||
|
||||
(Jess Weichler, [CC BY-SA 4.0][6])
|
||||
|
||||
If that doesn't make sense to you, that's okay. I didn't understand variables until I started coding as an adult.
|
||||
|
||||
Here is one example of how you might use a variable in code:
|
||||
|
||||
![Variables in Scratch][14]
|
||||
|
||||
(Jess Weichler, [CC BY-SA 4.0][6])
|
||||
|
||||
### Coordinates
|
||||
|
||||
Scratch uses a coordinate graph to measure the screen. The exact middle of the screen has a value of 0,0. The length of the screen (X-axis) is -240 to 240, the height (Y-axis) is -180 to 180.
|
||||
|
||||
The X and Y **coordinates** control where each sprite is on the screen, and you can code a sprite's X and Y coordinates to set a specific place using **[motion blocks][15]**.
|
||||
|
||||
![Coordinates in Scratch][16]
|
||||
|
||||
(Jess Weichler, [CC BY-SA 4.0][6])
|
||||
|
||||
### Put it all together
|
||||
|
||||
Think about the basics of any game; what are some elements you usually need?
|
||||
|
||||
Here are some examples:
|
||||
|
||||
* A goal
|
||||
* A way to win
|
||||
* A way to lose
|
||||
* An obstacle
|
||||
* A scoring system
|
||||
|
||||
|
||||
|
||||
With the techniques above, you have everything you need to create a playable game with these elements and more.
|
||||
|
||||
There are still heaps of code blocks in Scratch that I haven't mentioned. Keep exploring the possibilities. If you don't know what a code block does, put it in a script to see what happens!
|
||||
|
||||
Coming up with an idea for a game can be difficult. The great thing about the open source community, Scratchers included, is that we love to build upon one another's work. With that in mind, in the next article, I'll look at some of my favorite user-made projects for inspiration.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/20/10/advanced-scratch
|
||||
|
||||
作者：[Jess Weichler][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://opensource.com/users/cyanide-cupcake
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/binary_code_computer_screen.png?itok=7IzHK1nn (Binary code on a computer screen)
|
||||
[2]: https://opensource.com/article/20/9/scratch
|
||||
[3]: https://en.scratch-wiki.info/wiki/Categories
|
||||
[4]: https://scratch.mit.edu/
|
||||
[5]: https://opensource.com/sites/default/files/uploads/codekids3_1.png (Loops in Scratch)
|
||||
[6]: https://creativecommons.org/licenses/by-sa/4.0/
|
||||
[7]: https://opensource.com/sites/default/files/uploads/codekids3_2.png (Conditional statement blocks in Scratch)
|
||||
[8]: https://en.scratch-wiki.info/wiki/Blocks#Sensing_blocks
|
||||
[9]: https://en.scratch-wiki.info/wiki/Blocks#Operators_blocks
|
||||
[10]: https://opensource.com/sites/default/files/uploads/codekids3_3.png (Diamond-shaped blocks in Scratch)
|
||||
[11]: https://en.scratch-wiki.info/wiki/Making_Sprites_Detect_and_Sense_Other_Sprites
|
||||
[12]: https://opensource.com/sites/default/files/uploads/codekids3_4.png (Collision-detection script in Scratch)
|
||||
[13]: https://opensource.com/sites/default/files/uploads/codekids3_5.png (Variables in Scratch)
|
||||
[14]: https://opensource.com/sites/default/files/uploads/codekids3_6.png (Variables in Scratch)
|
||||
[15]: https://en.scratch-wiki.info/wiki/Motion_Blocks
|
||||
[16]: https://opensource.com/sites/default/files/uploads/codekids3_7.png (Coordinates in Scratch)
|
||||
@ -0,0 +1,102 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (Simplify your web experience with this internet protocol alternative)
|
||||
[#]: via: (https://opensource.com/article/20/10/gemini-internet-protocol)
|
||||
[#]: author: (Seth Kenlon https://opensource.com/users/seth)
|
||||
|
||||
Simplify your web experience with this internet protocol alternative
|
||||
======
|
||||
Discover new corners of a quieter and simpler internet with the Gemini
|
||||
Protocol.
|
||||
![Person typing on a 1980's computer][1]
|
||||
|
||||
If you've been on the internet for a very long time or you're just very resourceful, you might remember an early text-sharing protocol called [Gopher][2]. Gopher was eventually displaced by the HTTP protocol, which of course is the basis for the modern World Wide Web. For many people, the "internet" and the "World Wide Web" are the same thing, because many people don't consciously do anything online that's _not_ on the www subdomain.
|
||||
|
||||
But there have always been a variety of network protocols to share information over an interconnected network: Telnet, FTP, SSH, Torrent, GNUnet, and many more. Recently, there's been an addition to this collection of alternatives, and it's called [Gemini][3].
|
||||
|
||||
The Gemini protocol, named after the space mission between the rudimentary experiments of Project Mercury and Project Apollo, is meant to sit peacefully between Gopher and HTTP. It doesn't aim to replace the modern web, by any means, but it does try to create both a simplified web and a modernized Gopher.
|
||||
|
||||
This development, young though it may be, is significant for many reasons. People take issue with the modern web, of course, for reasons spanning the technical and the philosophical, but it's also just plain bloated. A million hits from a Google search can feel like overkill when all you really want is one reliable answer to a very specific question.
|
||||
|
||||
Many people use Gopher for this very reason: it's small enough to allow for niche interests that are easy to find. However, Gopher is an old protocol that makes assumptions about programming, networking, and browsing that just aren't applicable anymore. Gemini aims to bring the best of the web to a format that approximates Gopher but is easy to program for. A simple Gemini browser can be written in a few hundred lines of code, and there's a very good one written in about 1,600 lines. That's a powerful feature for programmers, students, and minimalists alike.
|
||||
|
||||
### How to browse Gemini
|
||||
|
||||
Like the early web, Gemini is small enough that there is a list of known servers running Gemini sites. Just as browsing an HTTP site requires a web browser, accessing a Gemini site requires a Gemini browser. There are already several available, listed on the [Gemini website][4].
|
||||
|
||||
The simplest one to run is the [AV-98][5] client. It's written in Python and runs in a terminal. To try it out, download it:
|
||||
|
||||
|
||||
```
|
||||
`$ git clone https://tildegit.org/solderpunk/AV-98.git`
|
||||
```
|
||||
|
||||
Change directory into the downloaded directory and run AV-98:
|
||||
|
||||
|
||||
```
|
||||
$ cd AV-98.git
|
||||
$ python3 ./main.py
|
||||
```
|
||||
|
||||
The client is an interactive prompt. It has limited commands, and the main one is simply `go` followed by a Gemini server address. Go to the list of known [Gemini servers][6], select one that seems interesting, and try visiting it:
|
||||
|
||||
|
||||
```
|
||||
AV-98> go gemini://example.club
|
||||
|
||||
Welcome to the example.club Gemini server!
|
||||
|
||||
Here are some folders of ASCII art:
|
||||
|
||||
[1] Penguins
|
||||
[2] Wildebeests
|
||||
[3] Demons
|
||||
```
|
||||
|
||||
Navigation is a matter of following numbered links. For instance, to navigate to the Penguins directory, enter `1` and press Enter:
|
||||
|
||||
|
||||
```
|
||||
AV-98> 1
|
||||
|
||||
[1] Gentoo
|
||||
[2] Emperor
|
||||
[3] Little Blue
|
||||
```
|
||||
|
||||
To go back, type `back` and press Enter:
|
||||
|
||||
|
||||
```
|
||||
`AV-98> back`
|
||||
```
|
||||
|
||||
For more commands, just enter `help`.
|
||||
|
||||
### Gemini as your web alternative
|
||||
|
||||
The Gemini protocol is simple enough for beginner-level and intermediate programmers to write clients for, and it's an easy and quick way to share content on the internet. While the World Wide Web's ubiquity is advantageous for widespread distribution, there's always room for alternatives. Check out Gemini and discover new corners of a quieter and simpler internet.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/20/10/gemini-internet-protocol
|
||||
|
||||
作者：[Seth Kenlon][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://opensource.com/users/seth
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/1980s-computer-yearbook.png?itok=eGOYEKK- (Person typing on a 1980's computer)
|
||||
[2]: https://en.wikipedia.org/wiki/Gopher_%28protocol%29
|
||||
[3]: https://gemini.circumlunar.space/
|
||||
[4]: https://gemini.circumlunar.space/clients.html
|
||||
[5]: https://tildegit.org/solderpunk/AV-98
|
||||
[6]: https://portal.mozz.us/gemini/gemini.circumlunar.space/servers
|
||||
@ -0,0 +1,63 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (Start using virtual tables in Apache Cassandra 4.0)
|
||||
[#]: via: (https://opensource.com/article/20/10/virtual-tables-apache-cassandra)
|
||||
[#]: author: (Ben Bromhead https://opensource.com/users/ben-bromhead)
|
||||
|
||||
Start using virtual tables in Apache Cassandra 4.0
|
||||
======
|
||||
What they are and how to use them.
|
||||
![Computer laptop in space][1]
|
||||
|
||||
Among the [many additions][2] in the recent [Apache Cassandra 4.0 beta release][3], virtual tables is one that deserves some attention.
|
||||
|
||||
In previous versions of Cassandra, users needed access to Java Management Extensions ([JMX][4]) to examine Cassandra details such as running compactions, clients, metrics, and a variety of configuration settings. Virtual tables removes these challenges. Cassandra 4.0 beta enables users to query those details and data as Cassandra Query Language (CQL) rows from a read-only system table.
|
||||
|
||||
Here is how the JMX-based mechanism in previous Cassandra versions worked. Imagine a user wants to check on the compaction status of a particular node in a cluster. The user first has to establish a JMX connection to run `nodetool compactionstats` on the node. This requirement immediately presents the user with a few complications. Is the user's client configured for JMX access? Are the Cassandra nodes and firewall configured to allow JMX access? Are the proper measures for security and auditing prepared and in place? These are only some of the concerns users had to contend with when dealing with in previous versions of Cassandra.
|
||||
|
||||
With Cassandra 4.0, virtual tables make it possible for users to query the information they need by utilizing their previously configured driver. This change removes all overhead associated with implementing and maintaining JMX access.
|
||||
|
||||
Cassandra 4.0 creates two new keyspaces to help users leverage virtual tables: `system_views` and `system_virtual_schema`. The `system_views` keyspace contains all the valuable information that users seek, usefully stored in a number of tables. The `system_virtual_schema` keyspace, as the name implies, stores all necessary schema information for those virtual tables.
|
||||
|
||||
![system_views and system_virtual_schema keyspaces and tables][5]
|
||||
|
||||
(Ben Bromhead, [CC BY-SA 4.0][6])
|
||||
|
||||
It's important to understand that the scope of each virtual table is restricted to its node. Any query of virtual tables will return data that is valid only for the node that acts as its coordinator, regardless of consistency. To simplify for this requirement, support has been added to several drivers to specify the coordinator node in these queries (the Python, DataStax Java, and other drivers now offer this support).
|
||||
|
||||
To illustrate, examine this `sstable_tasks` virtual table. This virtual table displays all operations on [SSTables][7], including compactions, cleanups, upgrades, and more.
|
||||
|
||||
![Querying the sstable_tasks virtual table][8]
|
||||
|
||||
(Ben Bromhead, [CC BY-SA 4.0][6])
|
||||
|
||||
If a user were to run `nodetool compactionstats` in a previous Cassandra version, this is the same type of information that would be displayed. Here, the query finds that the node currently has one active compaction. It also displays its progress and its keyspace and table. Thanks to the virtual table, a user can gather this information quickly, and just as efficiently gain the insight needed to correctly diagnose the cluster's health.
|
||||
|
||||
To be clear, Cassandra 4.0 doesn't eliminate the need for JMX access: JMX is still the only option for querying some metrics. That said, users will welcome the ability to pull key cluster metrics simply by using CQL. Thanks to the convenience afforded by virtual tables, users may be able to reinvest time and resources previously devoted to JMX tools into Cassandra itself. Client-side tooling should also begin to leverage the advantages offered by virtual tables.
|
||||
|
||||
If you are interested in the Cassandra 4.0 beta release and its virtual tables feature, [try it out][3].
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/20/10/virtual-tables-apache-cassandra
|
||||
|
||||
作者：[Ben Bromhead][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://opensource.com/users/ben-bromhead
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/computer_space_graphic_cosmic.png?itok=wu493YbB (Computer laptop in space)
|
||||
[2]: https://www.instaclustr.com/apache-cassandra-4-0-beta-released/
|
||||
[3]: https://cassandra.apache.org/download/
|
||||
[4]: https://en.wikipedia.org/wiki/Java_Management_Extensions
|
||||
[5]: https://opensource.com/sites/default/files/uploads/cassandra_virtual-tables.png (system_views and system_virtual_schema keyspaces and tables)
|
||||
[6]: https://creativecommons.org/licenses/by-sa/4.0/
|
||||
[7]: https://cassandra.apache.org/doc/latest/architecture/storage_engine.html#sstables
|
||||
[8]: https://opensource.com/sites/default/files/uploads/cassandra_virtual-tables_sstable_tasks.png (Querying the sstable_tasks virtual table)
|
||||
@ -0,0 +1,199 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (Design and document APIs using an open source cross-platform tool)
|
||||
[#]: via: (https://opensource.com/article/20/10/spec-first-development-apis)
|
||||
[#]: author: (Greg Schier https://opensource.com/users/gregschier)
|
||||
|
||||
Design and document APIs using an open source cross-platform tool
|
||||
======
|
||||
Insomnia Designer makes spec-first development more accessible by
|
||||
providing collaborative tools to organize, maintain, and validate API
|
||||
specs.
|
||||
![Computer laptop in space][1]
|
||||
|
||||
In the world of software-as-a-service (SaaS) and service-based architectures, it's not uncommon for companies to maintain dozens or even hundreds of APIs, often spanning multiple teams, programming languages, and environments. This variability makes it extremely difficult to see what's happening at a high level to prevent changes from having negative impacts.
|
||||
|
||||
It's estimated that 40% of large enterprises struggle with challenges to secure, scale, or ensure performance for APIs. Because of this, more and more companies are choosing to adopt a "spec-first development" approach by defining and documenting APIs in an external format like [OpenAPI][2]. Storing these documents together in a central location makes it much easier to design, discuss, and approve changes _before_ implementation.
|
||||
|
||||
In this tutorial, you'll use the recently released [Insomnia Designer][3] to document an API, explore it, and propose a change using a spec-first approach. Designer is a cross-platform, open source REST client that builds on top of Insomnia Core—a popular app for interacting with HTTP and GraphQL APIs—aiming to make spec-first development more accessible by providing collaborative tools to organize, maintain, and validate API specs. In essence, Core is best for exploring and debugging APIs while Designer is best for designing and documenting them.
|
||||
|
||||
In this how-to, you'll use the [Open Library API][4] as a base to have working examples to play with. You'll create a minimal OpenAPI spec to document the APIs, use Insomnia Designer to test and verify that what you've done is correct, and then make some design changes to the API using a spec-first approach.
|
||||
|
||||
### The spec-first workflow
|
||||
|
||||
Before you begin, you should understand the steps necessary to adopt a spec-first workflow. In spec-first development, a specification can be in one of two states:
|
||||
|
||||
* **Published spec:** A specification that describes a currently published API exactly
|
||||
* **Proposal spec:** A draft specification that contains changes that need to be implemented
|
||||
|
||||
|
||||
|
||||
From this information, you can define a workflow for making changes to an API:
|
||||
|
||||
1. Start with the published specification for the API
|
||||
2. Make changes to the specification to add or modify behavior
|
||||
3. Review the proposal spec to ensure the design is sufficient
|
||||
4. Implement changes in code to match the proposal
|
||||
5. Publish the proposal spec along with the API
|
||||
|
||||
|
||||
|
||||
Now that you understand the workflow for what you are trying to accomplish, open Insomnia Designer and start trying it out.
|
||||
|
||||
### Define the initial specification
|
||||
|
||||
Since you don't yet have a published specification for the Open Library API, you need to define one.
|
||||
|
||||
Start by creating a new blank document from the **Create** menu, give it a name, then click to the document to enter **Design View**. From here, you can start editing your spec.
|
||||
|
||||
![Create a new document][5]
|
||||
|
||||
(Greg Schier, [CC BY-SA 4.0][6])
|
||||
|
||||
The OpenAPI spec is most commonly written in [YAML][7] format and requires four top-level blocks to get started: `openapi`, `info`, `servers`, and `paths`. The following example defines each of these blocks with helpful comments to describe the purpose of each. Also, the `paths` block defines a route for `GET /recentchanges.json`:
|
||||
|
||||
|
||||
```
|
||||
# Specify that your document is the OpenAPI 3 format
|
||||
openapi: 3.0.0
|
||||
|
||||
# Define high-level metadata for the API
|
||||
info:
|
||||
version: 1.0.0
|
||||
title: Open Library API
|
||||
description: Open Library has a RESTful API
|
||||
|
||||
# Specify the base URL the API can be accessed from
|
||||
servers:
|
||||
- url: <http://openlibrary.org>
|
||||
|
||||
# Define operations for the API. This will be where most
|
||||
# of the work is done. The first route you'll be defining
|
||||
# is `GET /recentchanges.json`
|
||||
paths:
|
||||
/recentchanges.json:
|
||||
get:
|
||||
summary: Recent Changes
|
||||
```
|
||||
|
||||
OpenAPI provides much more than what's visible here, such as the ability to define authentication, response formats, reusable components, and more.
|
||||
|
||||
After copying the specification above into Insomnia Designer, you'll see three columns:
|
||||
|
||||
1. **Navigation sidebar (left):** Nested menu to make navigating larger documents easier
|
||||
2. **Spec editor (middle):** Text editor for editing the YAML document
|
||||
3. **Documentation preview:** Generated documentation to preview the specification
|
||||
|
||||
|
||||
|
||||
![Insomnia Designer UI with three columns][8]
|
||||
|
||||
(Greg Schier, [CC BY-SA 4.0][6])
|
||||
|
||||
Feel free to modify different parts of the specification to see what happens. As a safeguard, Insomnia Designer alerts you when you've done something wrong. For example, if you accidentally delete the colon on line 18, an error panel will display below the editor.
|
||||
|
||||
![Insomnia Designer UI error message][9]
|
||||
|
||||
(Greg Schier, [CC BY-SA 4.0][6])
|
||||
|
||||
Now that you have defined a specification, you can verify that your definition is correct by switching to **Debug** mode and sending a real request to the API. In Debug mode, you can see a single route was generated for the `GET /recentchanges.json` endpoint. Click the **Send** button beside the URL to execute the request and render the response in the right panel.
|
||||
|
||||
![Checking response in Insomnia Designer][10]
|
||||
|
||||
(Greg Schier, [CC BY-SA 4.0][6])
|
||||
|
||||
There you have it! You've successfully verified that the API specification you created matches the production API. Now you can move to the next step in the spec-first development workflow and propose a change.
|
||||
|
||||
### Create a proposal specification
|
||||
|
||||
According to the workflow outlined above, changes made to your API should first be defined in the specification. This has a number of benefits:
|
||||
|
||||
* Specifications can be checked into a central source-code repository
|
||||
* Changes are easy to review and approve
|
||||
* APIs are defined in a single, consistent format
|
||||
* Unnecessary code changes are avoided
|
||||
|
||||
|
||||
|
||||
Go ahead and propose a change to your API. While in Debug mode, I noticed the API returned hundreds of results. To improve performance and usability, it would be useful to limit the number of results returned to a specific amount. A common way of doing this is to accept a `limit` parameter in the query section of the URL, so go ahead and modify your specification to add a `limit` parameter.
|
||||
|
||||
In OpenAPI, you can define this by adding a `parameters` block to the route**:**
|
||||
|
||||
|
||||
```
|
||||
# ...
|
||||
paths:
|
||||
/recentchanges.json:
|
||||
get:
|
||||
summary: Recent Changes
|
||||
|
||||
# Add parameter to limit the number of results
|
||||
parameters:
|
||||
- name: limit
|
||||
in: query
|
||||
description: Limit number of results
|
||||
required: true
|
||||
schema:
|
||||
type: integer
|
||||
example: 1
|
||||
```
|
||||
|
||||
You can verify you defined it correctly by expanding the route within the preview and inspecting the parameters.
|
||||
|
||||
![Verifying spec definition in Insomnia][11]
|
||||
|
||||
(Greg Schier, [CC BY-SA 4.0][6])
|
||||
|
||||
### Review and implement the proposal
|
||||
|
||||
Now that you have created a proposal spec, you can have your team review and approve the changes. Insomnia Designer provides the ability to [sync API specifications to source control][12], allowing teams to review and approve changes to API specs the same way they do with source code.
|
||||
|
||||
For example, you might commit and push your proposed spec to a new branch in GitHub and create a pull request to await approval.
|
||||
|
||||
Because this is a tutorial on spec-first development, you won't implement the proposal yourself. The parameter you added is already supported by the API, however, so for the purpose of this article, use your imagination and pretend that your team has implemented the change.
|
||||
|
||||
### Verify the updated specification
|
||||
|
||||
Once the proposal has been implemented and deployed, you can switch to Debug mode, which will regenerate the requests based on your changes, and again verify that the spec matches the production API. To ensure the new query param is being sent, click the **Query** tab within Debug mode and observe that the `limit` parameter is set to your example value of `1`.
|
||||
|
||||
Once you send the request, you can verify that it returns only a single result. Change the `limit` to a different value or disable the query parameter (using the checkbox) to further verify things work as expected.
|
||||
|
||||
![Verifying things work as expected in Insomnia Designer][13]
|
||||
|
||||
(Greg Schier, [CC BY-SA 4.0][6])
|
||||
|
||||
### The power of spec-first development
|
||||
|
||||
This tutorial walked through a simplified example of spec-first development. In it, you created an OpenAPI specification, verified the specification matched the implementation, and simulated what it's like to propose a behavior change.
|
||||
|
||||
For a single API as simple as this demo, it may be difficult to see the full benefit of spec-first development. However, imagine being a product owner in a large organization managing hundreds of production APIs. Having well-documented specifications, accessible from a central location like Insomnia Designer, allows anyone within the organization to quickly get up to speed on any API.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/20/10/spec-first-development-apis
|
||||
|
||||
作者：[Greg Schier][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://opensource.com/users/gregschier
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/computer_space_graphic_cosmic.png?itok=wu493YbB (Computer laptop in space)
|
||||
[2]: https://github.com/OAI/OpenAPI-Specification/blob/master/versions/3.0.2.md
|
||||
[3]: https://insomnia.rest/products/designer
|
||||
[4]: https://openlibrary.org/developers/api
|
||||
[5]: https://opensource.com/sites/default/files/uploads/insomnia_newdocument.png (Create a new document)
|
||||
[6]: https://creativecommons.org/licenses/by-sa/4.0/
|
||||
[7]: https://yaml.org/
|
||||
[8]: https://opensource.com/sites/default/files/uploads/insomnia_columns.png (Insomnia Designer UI with three columns)
|
||||
[9]: https://opensource.com/sites/default/files/uploads/insomnia_error.png (Insomnia Designer UI error message)
|
||||
[10]: https://opensource.com/sites/default/files/uploads/insomnia_response.png (Checking response in Insomnia Designer)
|
||||
[11]: https://opensource.com/sites/default/files/uploads/insomnia_verifydefinition.png (Verifying spec definition in Insomnia)
|
||||
[12]: https://support.insomnia.rest/article/96-git-sync
|
||||
[13]: https://opensource.com/sites/default/files/uploads/insomnia_limit.png (Verifying things work as expected in Insomnia Designer)
|
||||
@ -0,0 +1,123 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (How to Clear Apt Cache and Reclaim Precious Disk Space)
|
||||
[#]: via: (https://itsfoss.com/clear-apt-cache/)
|
||||
[#]: author: (Abhishek Prakash https://itsfoss.com/author/abhishek/)
|
||||
|
||||
How to Clear Apt Cache and Reclaim Precious Disk Space
|
||||
======
|
||||
|
||||
How do you clear the apt cache? You simply use this [apt-get command][1] option:
|
||||
|
||||
```
|
||||
sudo apt-get clean
|
||||
```
|
||||
|
||||
But there is more to cleaning apt cache than just running the above command.
|
||||
|
||||
In this tutorial, I’ll explain what is apt cache, why is it used, why you would want to clean it and what other things you should know about purging apt cache.
|
||||
|
||||
I am going to use Ubuntu here for reference but since this is about apt, it is applicable to [Debian][2] and other Debian and Ubuntu-based distributions like Linux Mint, Deepin and more.
|
||||
|
||||
### What is apt cache? Why is it used?
|
||||
|
||||
When you install a package using apt-get or [apt command][3] (or DEB packages in the software center), the apt [package manager][4] downloads the package and its dependencies in .deb format and keeps it in /var/cache/apt/archives folder.
|
||||
|
||||
![][5]
|
||||
|
||||
While downloading, apt keeps the deb package in /var/cache/apt/archives/partial directory. When the deb package is downloaded completely, it is moved out to /var/cache/apt/archives directory.
|
||||
|
||||
Once the deb files for the package and its dependencies are downloaded, your system [installs the package from these deb files][6].
|
||||
|
||||
Now you see the use of cache? The system needs a place to keep the package files somewhere before installing them. If you are aware of the [Linux directory structure][7], you would understand that /var/cache is the appropriate here.
|
||||
|
||||
#### Why keep the cache after installing the package?
|
||||
|
||||
The downloaded deb files are not removed from the directory immediately after the installation is completed. If you remove a package and reinstall it, your system will look for the package in the cache and get it from here instead of downloading it again (as long as the package version in the cache is the same as the version in remote repository).
|
||||
|
||||
This is much quicker. You can try this on your own and see how long a program takes to install the first time, remove it and install it again. You can [use the time command to find out how long does it take to complete a command][8]: _**time sudo apt install package_name**_.
|
||||
|
||||
I couldn’t find anything concrete on the cache retention policy so I cannot say how long does Ubuntu keep the downloaded packages in the cache.
|
||||
|
||||
#### Should you clean apt cache?
|
||||
|
||||
It depends on you. If you are running out of disk space on root, you could clean apt cache and reclaim the disk space. It is one of the [several ways to free up disk space on Ubuntu][9].
|
||||
|
||||
Check how much space the cache takes with the [du command][10]:
|
||||
|
||||
![][11]
|
||||
|
||||
Sometime this could go in 100s of MB and this space could be crucial if you are running a server.
|
||||
|
||||
#### How to clean apt cache?
|
||||
|
||||
If you want to clear the apt cache, there is a dedicated command to do that. So don’t go about manually deleting the cache directory. Simply use this command:
|
||||
|
||||
```
|
||||
sudo apt-get clean
|
||||
```
|
||||
|
||||
This will remove the content of the /var/cache/apt/archives directory (except the lock file). Here’s a dry run (simulation) of what the apt-get clean command deletes:
|
||||
|
||||
![][12]
|
||||
|
||||
There is another command that deals with cleaning the apt cache:
|
||||
|
||||
```
|
||||
sudo apt-get autoclean
|
||||
```
|
||||
|
||||
Unlike clean, autoclean only removes the packages that are not possible to download from the repositories.
|
||||
|
||||
Suppose you installed package xyz. Its deb files remain in the cache. If there is now a new version of xyz package available in the repository, this existing xyz package in the cache is now outdated and useless. The autoclean option will delete such useless packages that cannot be downloaded anymore.
|
||||
|
||||
#### Is it safe to delete apt cache?
|
||||
|
||||
![][13]
|
||||
|
||||
Yes. It is completely safe to clear the cache created by apt. It won’t negatively impact the performance of the system. Maybe if you reinstall the package it will take a bit longer to download but that’s about it.
|
||||
|
||||
Again, use the apt-get clean command. It is quicker and easier than manually deleting cache directory.
|
||||
|
||||
You may also use graphical tools like [Stacer][14] or [Bleachbit][15] for this purpose.
|
||||
|
||||
#### Conclusion
|
||||
|
||||
At the time of writing this article, there is no built-in option with the newer apt command. However, keeping backward compatibility, _**apt clean**_ can still be run (which should be running apt-get clean underneath it). Please refer to this article to [know the difference between apt and apt-get][16].
|
||||
|
||||
I hope you find this explanation about apt cache interesting. It is not something essential but knowing this little things make you more knowledgeable about your Linux system.
|
||||
|
||||
I welcome your feedback and suggestions in the comment section.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://itsfoss.com/clear-apt-cache/
|
||||
|
||||
作者：[Abhishek Prakash][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://itsfoss.com/author/abhishek/
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://itsfoss.com/apt-get-linux-guide/
|
||||
[2]: https://www.debian.org/
|
||||
[3]: https://itsfoss.com/apt-command-guide/
|
||||
[4]: https://itsfoss.com/package-manager/
|
||||
[5]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2020/10/apt-get-clean-cache.png?resize=800%2C470&ssl=1
|
||||
[6]: https://itsfoss.com/install-deb-files-ubuntu/
|
||||
[7]: https://linuxhandbook.com/linux-directory-structure/
|
||||
[8]: https://linuxhandbook.com/time-command/
|
||||
[9]: https://itsfoss.com/free-up-space-ubuntu-linux/
|
||||
[10]: https://linuxhandbook.com/find-directory-size-du-command/
|
||||
[11]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2020/10/apt-cache-archive-size.png?resize=800%2C233&ssl=1
|
||||
[12]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2020/10/apt-get-clean-ubuntu.png?resize=800%2C339&ssl=1
|
||||
[13]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2020/10/Clear-Apt-Cache.png?resize=800%2C450&ssl=1
|
||||
[14]: https://itsfoss.com/optimize-ubuntu-stacer/
|
||||
[15]: https://itsfoss.com/use-bleachbit-ubuntu/
|
||||
[16]: https://itsfoss.com/apt-vs-apt-get-difference/
|
||||
@ -0,0 +1,112 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (geekpi)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (Integrate your calendar with Ansible to avoid schedule conflicts)
|
||||
[#]: via: (https://opensource.com/article/20/10/calendar-ansible)
|
||||
[#]: author: (Nicolas Leiva https://opensource.com/users/nicolas-leiva)
|
||||
|
||||
Integrate your calendar with Ansible to avoid schedule conflicts
|
||||
======
|
||||
Make sure your automation workflow's schedule doesn't conflict with
|
||||
something else by integrating a calendar app into Ansible.
|
||||
![Calendar close up snapshot][1]
|
||||
|
||||
Is "anytime" a good time to execute your automation workflow? The answer is probably no, for different reasons.
|
||||
|
||||
If you want to avoid simultaneous changes to minimize the impact on critical business processes and reduce the risk of unintended service disruptions, then no one else should be attempting to make changes at the same time your automation is running.
|
||||
|
||||
In some scenarios, there could be an ongoing scheduled maintenance window. Or maybe there is a big event coming up, a critical business time, or a holiday—or maybe you prefer not to make changes on a Friday night.
|
||||
|
||||
![Street scene with a large calendar and people walking][2]
|
||||
|
||||
([Curtis MacNewton][3], [CC BY-ND 2.0][4])
|
||||
|
||||
Whatever the reason, you want to signal this information to your automation platform and prevent the execution of periodic or ad-hoc tasks during specific time slots. In change management jargon, I am talking about specifying blackout windows when change activity should not occur.
|
||||
|
||||
### Calendar integration in Ansible
|
||||
|
||||
How can you accomplish this in [Ansible][5]? While it has no calendar function per se, Ansible's extensibility will allow it to integrate with any calendar application that has an API.
|
||||
|
||||
The goal is this: Before you execute any automation or change activity, you execute a `pre-task` that checks whether something is already scheduled in the calendar (now or soon enough) and confirms you are not in the middle of a blocked timeslot.
|
||||
|
||||
Imagine you have a fictitious module named `calendar`, and it can connect to a remote calendar, like Google Calendar, to determine if the time you specify has otherwise been marked as busy. You could write a playbook that looks like this:
|
||||
|
||||
|
||||
```
|
||||
\- name: Check if timeslot is taken
|
||||
calendar:
|
||||
time: "{{ ansible_date_time.iso8601 }}"
|
||||
register: output
|
||||
```
|
||||
|
||||
Ansible facts will give `ansible_date_time`, which is passed to the `calendar` module to verify the time availability so that it can register the response (`output`) to use in subsequent tasks.
|
||||
|
||||
If your calendar looks like this:
|
||||
|
||||
![Google Calendar screenshot][6]
|
||||
|
||||
(Nicolas Leiva, [CC BY-SA 4.0][7])
|
||||
|
||||
Then the output of this task would highlight the fact this timeslot is taken (`busy: true`):
|
||||
|
||||
|
||||
```
|
||||
ok: [localhost] => {
|
||||
"output": {
|
||||
"busy": true,
|
||||
"changed": false,
|
||||
"failed": false,
|
||||
"msg": "The timeslot 2020-09-02T17:53:43Z is busy: true"
|
||||
}
|
||||
}
|
||||
```
|
||||
|
||||
### Prevent tasks from running
|
||||
|
||||
Next, [Ansible Conditionals][8] will help prevent the execution of any further tasks. As a simple example, you could use a `when` statement on the next task to enforce that it runs only when the field `busy` in the previous output is not `true`:
|
||||
|
||||
|
||||
```
|
||||
tasks:
|
||||
- shell: echo "Run this only when not busy!"
|
||||
when: not output.busy
|
||||
```
|
||||
|
||||
### Conclusion
|
||||
|
||||
In a [previous article][9], I said Ansible is a framework to wire things together, interconnecting different building blocks to orchestrate an end-to-end automation workflow.
|
||||
|
||||
This article looked at how playbooks can integrate or talk to a calendar application to check availability. However, I am just scratching the surface! For example, your tasks could also block a timeslot in the calendar… the sky is the limit.
|
||||
|
||||
In my next article, I will dig into how the `calendar` module is built and how other programming languages can be used with Ansible. Stay tuned if you are a [Go][10] fan like me!
|
||||
|
||||
* * *
|
||||
|
||||
_This originally appeared on Medium as [Ansible and Google Calendar integration for change management][11] under a CC BY-SA 4.0 license and is republished with permission._
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/20/10/calendar-ansible
|
||||
|
||||
作者：[Nicolas Leiva][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://opensource.com/users/nicolas-leiva
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/calendar.jpg?itok=jEKbhvDT (Calendar close up snapshot)
|
||||
[2]: https://opensource.com/sites/default/files/uploads/street-calendar.jpg (Street scene with a large calendar and people walking)
|
||||
[3]: https://www.flickr.com/photos/7841127@N02/4217116202
|
||||
[4]: https://creativecommons.org/licenses/by-nd/2.0/
|
||||
[5]: https://docs.ansible.com/ansible/latest/index.html
|
||||
[6]: https://opensource.com/sites/default/files/uploads/googlecalendarexample.png (Google Calendar screenshot)
|
||||
[7]: https://creativecommons.org/licenses/by-sa/4.0/
|
||||
[8]: https://docs.ansible.com/ansible/latest/user_guide/playbooks_conditionals.html
|
||||
[9]: https://medium.com/swlh/python-and-ansible-to-automate-a-network-security-workflow-28b9a44660c6
|
||||
[10]: https://golang.org/
|
||||
[11]: https://medium.com/swlh/ansible-and-google-calendar-integration-for-change-management-7c00553b3d5a
|
||||
@ -0,0 +1,106 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (Protect your network with open source tools)
|
||||
[#]: via: (https://opensource.com/article/20/10/apache-security-tools)
|
||||
[#]: author: (Chantale Benoit https://opensource.com/users/chantalebenoit)
|
||||
|
||||
Protect your network with open source tools
|
||||
======
|
||||
Apache Syncope and Metron can help you secure your network against
|
||||
unauthorized access and data loss.
|
||||
![A lock on the side of a building][1]
|
||||
|
||||
System integrity is essential, especially when you're charged with safeguarding other people's personal details on your network. It's critical that system administrators are familiar with security tools, whether their purview is a home, a small business, or an organization with hundreds or thousands of employees.
|
||||
|
||||
### How cybersecurity works
|
||||
|
||||
Cybersecurity involves securing networks against unauthorized access. However, there are many attack vectors out there that most people don't consider. The cliché of a lone hacker manually dueling with firewall rules until they gain access to a network is popular—but wildly inaccurate. Security breaches happen through automation, malware, phishing, ransomware, and more. You can't directly fight every attack as it happens, and you can't count on every computer user to exercise common sense. Therefore, you have to design a system that resists intrusion and protects users against outside attacks as much as it protects them from their own mistakes.
|
||||
|
||||
The advantage of open source security tools is that they keep vulnerabilities transparent. They give full visibility into their codebase and are supported by a global community of experts working together to create strong, tried-and-tested code.
|
||||
|
||||
With so many domains needing protection, there's no single cybersecurity solution that fits every situation, but here are two that you should consider.
|
||||
|
||||
### Apache Syncope
|
||||
|
||||
[Apache Syncope][2] is an open source system for managing digital identities in an enterprise environment. From focusing on identity lifecycle management and identity storage to provisioning engines and accessing management capabilities, Apache Syncope is a comprehensive identity management solution. It also provides monitoring and security features for third-party applications.
|
||||
|
||||
Apache Syncope synchronizes users, groups, and other objects. _Users_ represent the buildup of virtual identities and account information fragmented across external resources. _Groups_ are entities on external resources that support the concept of LDAP or Active Directory. _Objects_ are entities such as printers, services, and sensors. It also does full reconciliation and live synchronization from external resources with workflow-based approval.
|
||||
|
||||
#### Third-party applications
|
||||
|
||||
Apache Syncope also exposes a fully compliant [JAX-RS][3] 2.0 [RESTful][4] interface to enable third-party applications written in any programming language. These applications consume identity management services, such as:
|
||||
|
||||
* **Logic:** Syncope implements business logic that can be triggered through REST services and controls additional features such as notifications, reports, and auditing.
|
||||
* **Provisioning:** It manages the internal and external representation of users, groups, and objects through workflow and specific connectors.
|
||||
* **Workflow:** Syncope supports Activiti or Flowable [business process management (BPM)][5] workflow engines and allows defining new and custom workflows when needed.
|
||||
* **Persistence:** It manages all data, such as users, groups, attributes, and resources, at a high level using a standard [JPA 2.0][6] approach. The data is further persisted to an underlying database, such as internal storage.
|
||||
* **Security:** Syncope defines a fine-grained set of entitlements, which are granted to administrators and enable the implementation of delegated administration scenarios.
|
||||
|
||||
|
||||
|
||||
#### Syncope extensions
|
||||
|
||||
Apache Syncope's features can be enhanced with [extensions][7], which add a REST endpoint and manage the persistence of additional entities, tweak the provisioning layer, and add features to the user interface.
|
||||
|
||||
Some popular extensions include:
|
||||
|
||||
* **Swagger UI** works as a user interface for Syncope RESTful services.
|
||||
* **SSO support** provides OpenID Connect and SAML 2.0 access to administrative or end-user web interfaces.
|
||||
* **Apache Camel provisioning manager** delegates the execution of the provisioning process to a group of Apache Camel routes. It can be dynamically changed at the runtime through the REST interfaces or the administrative console, and modifications are also instantly available for processing.
|
||||
* **Elasticsearch** provides an alternate internal search engine for users, groups, and objects through an external [Elasticsearch][8] cluster.
|
||||
|
||||
|
||||
|
||||
### Apache Metron
|
||||
|
||||
Security information and event management ([SIEM][9]) gives admins insights into the activities happening within their IT environment. It combines the concepts of security event management (SEM) with security information management (SIM) into one functionality. SIEM collects security data from network devices, servers, and domain controllers, then aggregates and analyzes the data to detect malicious threats and payloads.
|
||||
|
||||
[Apache Metron][10] is an advanced security analytics framework that detects cyber anomalies, such as phishing activity and malware infections. Further, it enables organizations to take corrective measures to counter the identified anomalies.
|
||||
|
||||
It also interprets and normalizes security events into standard JSON language, which makes it easier to analyze security events, such as:
|
||||
|
||||
* An employee flagging a suspicious email
|
||||
* An authorized or unauthorized software download by an employee to a company device
|
||||
* A security lapse due to a server outage
|
||||
|
||||
|
||||
|
||||
Apache Metron provides security alerts, labeling, and data enrichment. It can also store and index security events. Its four key capabilities are:
|
||||
|
||||
* **Security data lake:** Metron is a cost-effective way to store and combine a wide range of business and security data. The security data lake provides the amount of data required to power discovery analytics. It also provides a mechanism to search and query for operational analytics.
|
||||
* **Pluggable framework:** It provides a rich set of parsers for common security data sources such as pcap, NetFlow, Zeek (formerly Bro), Snort, FireEye, and Sourcefire. You can also add custom parsers for new data sources, including enrichment services for more contextual information, to the raw streaming data. The pluggable framework provides extensions for threat-intel feeds and lets you customize security dashboards. Machine learning and other models can also be plugged into real-time streams and provide extensibility.
|
||||
* **Threat detection platform:** It uses machine learning algorithms to detect anomalies in a system. It also helps analysts extract and reconstruct full packets to understand the attacker's identity, what data was leaked, and where the data was sent.
|
||||
* **Incident response application:** This refers to evolved SIEM capabilities, including alerting, threat intel frameworks, and agents to ingest data sources. Incident response applications include packet replay utilities, evidence storage, and hunting services commonly used by security operations center analysts.
|
||||
|
||||
|
||||
|
||||
### Security matters
|
||||
|
||||
Incorporating open source security tools into your IT infrastructure is imperative to keep your organization safe and secure. Open source tools, like Syncope and Metron from Apache, can help you identify and counter security threats. Learn to use them well, file bugs as you find them, and help the open source community protect the world's data.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/20/10/apache-security-tools
|
||||
|
||||
作者：[Chantale Benoit][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://opensource.com/users/chantalebenoit
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/BUSINESS_3reasons.png?itok=k6F3-BqA (A lock on the side of a building)
|
||||
[2]: https://syncope.apache.org/
|
||||
[3]: https://jax-rs.github.io/apidocs/2.0/
|
||||
[4]: https://www.redhat.com/en/topics/api/what-is-a-rest-api
|
||||
[5]: https://www.redhat.com/en/topics/automation/what-is-business-process-management
|
||||
[6]: http://openjpa.apache.org/openjpa-2.0.0.html
|
||||
[7]: http://syncope.apache.org/docs/2.1/reference-guide.html#extensions
|
||||
[8]: https://opensource.com/life/16/6/overview-elastic-stack
|
||||
[9]: https://en.wikipedia.org/wiki/Security_information_and_event_management
|
||||
[10]: http://metron.apache.org/
|
||||
@ -0,0 +1,104 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (Top 5 open source alternatives to Google Analytics)
|
||||
[#]: via: (https://opensource.com/article/18/1/top-5-open-source-analytics-tools)
|
||||
[#]: author: (Scott Nesbitt https://opensource.com/users/scottnesbitt)
|
||||
|
||||
Top 5 open source alternatives to Google Analytics
|
||||
======
|
||||
These four versatile web analytics tools provide valuable insights on
|
||||
your customers and site visitors while keeping you in control.
|
||||
![Analytics: Charts and Graphs][1]
|
||||
|
||||
If you have a website or run an online business, collecting data on where your visitors or customers come from, where they land on your site, and where they leave _is vital._ Why? That information can help you better target your products and services, and beef up the pages that are turning people away.
|
||||
|
||||
To gather that kind of information, you need a web analytics tool.
|
||||
|
||||
Many businesses of all sizes use Google Analytics. But if you want to keep control of your data, you need a tool that _you_ can control. You won’t get that from Google Analytics. Luckily, Google Analytics isn’t the only game on the web.
|
||||
|
||||
Here are four open source alternatives to Google Analytics.
|
||||
|
||||
### Matomo
|
||||
|
||||
Let’s start with the open source application that rivals Google Analytics for functions: [Matomo][2] (formerly known as Piwik). Matomo does most of what Google Analytics does, and chances are it offers the features that you need.
|
||||
|
||||
Those features include metrics on the number of visitors hitting your site, data on where they come from (both on the web and geographically), the pages from which they leave, and the ability to track search engine referrals. Matomo also offers many reports, and you can customize the dashboard to view the metrics that you want to see.
|
||||
|
||||
To make your life easier, Matomo integrates with more than 65 content management, e-commerce, and online forum systems, including WordPress, Magneto, Joomla, and vBulletin, using plugins. For any others, you can simply add a tracking code to a page on your site.
|
||||
|
||||
You can [test-drive][3] Matomo or use a [hosted version][4].
|
||||
|
||||
### Open Web Analytics
|
||||
|
||||
If there’s a close second to Matomo in the open source web analytics stakes, it’s [Open Web Analytics][5]. In fact, it includes key features that either rival Google Analytics or leave it in the dust.
|
||||
|
||||
In addition to the usual raft of analytics and reporting functions, Open Web Analytics tracks where on a page, and on what elements, visitors click; provides [heat maps][6] that show where on a page visitors interact the most; and even does e-commerce tracking.
|
||||
|
||||
Open Web Analytics has a [WordPress plugin][7] and can [integrate with MediaWiki][8] using a plugin. Or you can add a snippet of [JavaScript][9] or [PHP][10] code to your web pages to enable tracking.
|
||||
|
||||
Before you [download][11] the Open Web Analytics package, you can [give the demo a try][12] to see it it’s right for you.
|
||||
|
||||
### AWStats
|
||||
|
||||
Web server log files provide a rich vein of information about visitors to your site, but tapping into that vein isn't always easy. That's where [AWStats][13] comes to the rescue. While it lacks the most modern look and feel, AWStats more than makes up for that with breadth of data it can present.
|
||||
|
||||
That information includes the number of unique visitors, how long those visitors stay on the site, the operating system and web browsers they use, the size of a visitor's screen, and the search engines and search terms people use to find your site. AWStats can also tell you the number of times your site is bookmarked, track the pages where visitors enter and exit your sites, and keep a tally of the most popular pages on your site.
|
||||
|
||||
These features only scratch the surface of AWStats's capabilities. It also works with FTP and email logs, as well as [syslog][14] files. AWStats can gives you a deep insight into what's happening on your website using data that stays under your control.
|
||||
|
||||
### Countly
|
||||
|
||||
[Countly][15] bills itself as a "secure web analytics" platform. While I can't vouch for its security, Countly does a solid job of collecting and presenting data about your site and its visitors.
|
||||
|
||||
Heavily targeting marketing organizations, Countly tracks data that is important to marketers. That information includes site visitors' transactions, as well as which campaigns and sources led visitors to your site. You can also create metrics that are specific to your business. Countly doesn't forgo basic web analytics; it also keeps track of the number of visitors on your site, where they're from, which pages they visited, and more.
|
||||
|
||||
You can use the hosted version of Countly or [grab the source code][16] from GitHub and self-host the application. And yes, there are [differences between the hosted and self-hosted versions][17] of Countly.
|
||||
|
||||
### Plausible
|
||||
|
||||
[Plausible][18] is a newer kid on the open source analytics tools block. It’s lean, it’s fast, and only collects a small amount of information — that includes numbers of unique visitors and the top pages they visited, the number of page views, the bounce rate, and referrers. Plausible is simple and very focused.
|
||||
|
||||
What sets Plausible apart from its competitors is its heavy focus on privacy. The project creators state that the tool doesn’t collect or store any information about visitors to your website, which is particularly attractive if privacy is important to you. You can read more about that [here][19].
|
||||
|
||||
There’s a [demo instance][20] that you check out. After that, you can either [self-host][21] Plausible or sign up for a [paid, hosted account][22].
|
||||
|
||||
**Share your favorite open source web analytics tool with us in the comments.**
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/18/1/top-5-open-source-analytics-tools
|
||||
|
||||
作者：[Scott Nesbitt][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://opensource.com/users/scottnesbitt
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/analytics-graphs-charts.png?itok=sersoqbV (Analytics: Charts and Graphs)
|
||||
[2]: https://matomo.org/
|
||||
[3]: https://demo.matomo.org/index.php?module=CoreHome&action=index&idSite=3&period=day&date=yesterday
|
||||
[4]: https://www.innocraft.cloud/
|
||||
[5]: http://www.openwebanalytics.com/
|
||||
[6]: http://en.wikipedia.org/wiki/Heat_map
|
||||
[7]: https://github.com/padams/Open-Web-Analytics/wiki/WordPress-Integration
|
||||
[8]: https://github.com/padams/Open-Web-Analytics/wiki/MediaWiki-Integration
|
||||
[9]: https://github.com/padams/Open-Web-Analytics/wiki/Tracker
|
||||
[10]: https://github.com/padams/Open-Web-Analytics/wiki/PHP-Invocation
|
||||
[11]: https://github.com/padams/Open-Web-Analytics
|
||||
[12]: http://demo.openwebanalytics.com/
|
||||
[13]: http://www.awstats.org
|
||||
[14]: https://en.wikipedia.org/wiki/Syslog
|
||||
[15]: https://count.ly/web-analytics
|
||||
[16]: https://github.com/Countly
|
||||
[17]: https://count.ly/pricing#compare-editions
|
||||
[18]: https://plausible.io
|
||||
[19]: https://plausible.io/data-policy
|
||||
[20]: https://plausible.io/plausible.io
|
||||
[21]: https://plausible.io/self-hosted-web-analytics
|
||||
[22]: https://plausible.io/register
|
||||
@ -0,0 +1,106 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (5 ways organizations can lean into failure and transform it into success)
|
||||
[#]: via: (https://opensource.com/article/20/10/organizations-can-lean-failure)
|
||||
[#]: author: (Dawn Parzych https://opensource.com/users/dawnparzych)
|
||||
|
||||
5 ways organizations can lean into failure and transform it into success
|
||||
======
|
||||
Removing the fear of failure fosters innovation and open-mindedness,
|
||||
turning mistakes into opportunities for growth and improvement.
|
||||
![failure sign at a party, celebrating failure][1]
|
||||
|
||||
> "If failure is not an option, then neither is success."—Seth Godin
|
||||
|
||||
Success is something we all strive toward, but the road to success has twists and turns, which are also known as our failures. But instead of giving up when things don't go my way, I have learned to look at failures as learning opportunities. In fact, I now proudly admit that I'm a failure:
|
||||
|
||||
* I failed my driving test the first time I took it.
|
||||
* I have not gotten every job I've ever applied or interviewed for.
|
||||
* Most of the articles I've written have not gone viral.
|
||||
|
||||
|
||||
|
||||
As software engineers, our industry may be competitive, but we need to remove the stigma associated with failing. One way of doing that is to talk about our failures. The more we hear and talk about failures, the more acceptable it becomes. We need to think about failures as learning opportunities, not a time to shame and ridicule others (or ourselves).
|
||||
|
||||
When we have failed, or think we have made a mistake, most of us get that pit in the bottom of our stomach, and the negative self-talk can kick in almost instantly. This reaction occurs because there are often consequences for mistakes, which can impact us personally as well as the organizations we work for.
|
||||
|
||||
Let's consider a hypothetical example: A software engineer submits a pull request for a new feature. It gets merged and released to production. Something goes wrong, and the application begins throwing errors. Customers can't log in. Sadly this isn't the first time this has happened. Some customers are fed up with the application breaking and have canceled their contracts. The CTO is furious. They want to know who is responsible for this feature being released. The team is understaffed because several team members have left the company, and those that remain are [burned out][2]. The incident takes way longer than usual to be resolved, and everyone is grumpy at the end.
|
||||
|
||||
This worst-case scenario doesn't mean we should always play it safe and not take risks. We need to balance the risks with the rewards when making technical decisions at work and with the open source projects we work on. I like to visualize success and failure as two opposite banks of a river, connected by a bridge. That bridge is built out of knowledge, learning, and understanding. Failure is when we grow, but only if we're learning from those failures and have a good mixture of success sprinkled in.
|
||||
|
||||
### What is needed to accept failure?
|
||||
|
||||
Embracing failure from a personal and organizational point of view doesn't happen overnight. It takes both time and the right culture. Start with one of the five areas outlined below.
|
||||
|
||||
#### Have a growth mindset
|
||||
|
||||
In the book _Growth_, Carol Dweck describes two types of mindsets: growth and fixed. A person with a fixed mindset believes in innate capabilities—you're either born with it, or you're not. Failure represents a limit on one's abilities.
|
||||
|
||||
A person with a growth mindset believes that individual effort and attitude determine one's abilities and that they can learn and improve as long as they put in the effort. Failure represents an opportunity to grow.
|
||||
|
||||
To encourage growth means to encourage failure. But saying "it's OK to fail" is not the same as creating a culture where it honestly is OK to fail. That requires psychological safety and a blameless culture.
|
||||
|
||||
#### Create a blameless culture
|
||||
|
||||
A blameless culture focuses on _where_ a system or a process failed, not on _who_ is responsible. If you spend time after an incident looking for and attributing root cause to human error, you are assigning blame. Instead, look for how things can be improved. What broke? How did it break? How can you prevent it in the future?
|
||||
|
||||
![Image of swampy area with overlaid quote reading "If a junior engineer asks where outages come from, I think a cute thing to tell them is 'The server is crying.' And if they ask why the server is crying, another cute thing to tell them is 'probably becaus][3]
|
||||
|
||||
Published with permission from Joshua Zimmerman (@TheJewberwocky)
|
||||
|
||||
#### Foster psychological safety
|
||||
|
||||
A blameless culture cannot exist without psychological safety. Psychological safety is the ability to show up to work without fear; you feel included in the whole, that it is safe to learn, safe to contribute, and safe to challenge the status quo without fear of consequences. Employees need to feel empowered to speak up if they see processes that need to be improved if they are concerned with security or lack of security procedures in place. They need to feel they won't be blamed for taking a risk where the end result wasn't quite what was expected.
|
||||
|
||||
One way to create a blameless culture and provide psychological safety is to eliminate the word "why" from your vocabulary. Why is used quite frequently—there are problem-solving techniques called ["The "5 Whys."][4] The problem with "why" is it is subtly coded instead as "explain yourself." Having to answer "why" questions put people on the defensive, and they spend time focusing on what the "right" answer is instead of answering honestly. Instead, switch to using "what" or "how" questions. "How" and "what" questions promote concrete action.
|
||||
|
||||
Consider the difference in these questions:
|
||||
|
||||
* Why did last night's release cause a series of exceptions?
|
||||
vs.
|
||||
* How were the exceptions triggered?
|
||||
|
||||
|
||||
|
||||
> "Recently, I was asked if I was going to fire an employee who made a mistake that cost the company $600,000. 'No,' I replied, 'I just spent $600,000 training him. Why would I want somebody else to hire his experience?'"— Thomas J. Watson, Chairman & CEO of IBM, 1914-1956
|
||||
|
||||
#### Remember the importance of play
|
||||
|
||||
The final aspect of embracing failure is to make time to play. Play shapes our brains and fosters empathy. From a young age, we learn to play games, play on a sports team, play on our own, etc. Chances are you didn't always play on an undefeated sports team or win every single game you've ever played, but practice helped you get better over time no matter what. These experiences teach us to be comfortable with failure and to take it in stride with growth and improvement.
|
||||
|
||||
#### Experimentation leads to learning
|
||||
|
||||
Now that you're ready to embrace failure in your DevOps or engineering practices, where do you start? One of the first processes to look at is the build process. As you most likely know, builds can sometimes result in failures. Changing your build process to include [progressive delivery][5] techniques helps you release features in a controlled manner as opposed to a big bang. Using ring deployments or a canary launch, you can see how a feature performs for a small group of users. If there is a failure, the blast radius has been minimized.
|
||||
|
||||
Another process that can help you learn about your applications and systems is experimentation. Experiments provide a number of learning opportunities, and they don't always go as expected. Some failures can turn into wild successes; for example—[Post-it Notes][6]. Experiments allow us to test a hypothesis and learn new things. Experimenting with software can look like running an A/B test to see which look and feel leads to greater engagement or collecting page load time metrics to see if adding pagination to search results negatively impacts performance.
|
||||
|
||||
A popular type of experimentation is to run a chaos day or game day. With a game day, you purposely cause a system or application to fail. This combines the notion of play, failure, and learning. During this controlled experiment, you learn how your system behaves during failure scenarios. The knowledge gained during game days can be used to put safety measures in place or define processes for what to do when a specific failure occurs.
|
||||
|
||||
### Lean into failure
|
||||
|
||||
Failure can be scary; it is seen as a negative and something we want to avoid. I call on you to change your perspective on this. If you're not failing, you're not learning.
|
||||
|
||||
I challenge you to normalize failure and help reduce the stigma by sharing a failure of yours. Share your failures in the comments below or tag me on social media.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/20/10/organizations-can-lean-failure
|
||||
|
||||
作者：[Dawn Parzych][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://opensource.com/users/dawnparzych
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/fail_failure_celebrate.png?itok=LbvDAEZF (failure sign at a party, celebrating failure)
|
||||
[2]: https://opensource.com/article/19/11/burnout-open-source-communities
|
||||
[3]: https://opensource.com/sites/default/files/uploads/quote-failure-opensource_0.png
|
||||
[4]: https://en.wikipedia.org/wiki/Five_whys
|
||||
[5]: https://launchdarkly.com/blog/all-the-canaries-lived-its-time-to-adopt-progressive-delivery/
|
||||
[6]: https://www.ideatovalue.com/insp/nickskillicorn/2017/04/true-story-post-notes-almost-failed/
|
||||
@ -0,0 +1,131 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (How to Install Deepin Desktop on Ubuntu 20.04 LTS)
|
||||
[#]: via: (https://itsfoss.com/install-deepin-ubuntu/)
|
||||
[#]: author: (Ankush Das https://itsfoss.com/author/ankush/)
|
||||
|
||||
How to Install Deepin Desktop on Ubuntu 20.04 LTS
|
||||
======
|
||||
|
||||
_**This tutorial shows you the proper steps to install the Deepin desktop environment on Ubuntu. Removal steps are also mentioned.**_
|
||||
|
||||
Deepin is undoubtedly a [beautiful Linux distribution][1]. The recently released [Deepin version 20][2] makes it even more beautiful.
|
||||
|
||||
Now, [Deepin Linux][3] is based on [Debian][4] and the default repository mirrors are too slow. If you would rather stay with Ubuntu, you have the Deepin variant of Ubuntu in the form [UbuntuDDE Linux distribution][5]. It is not one of the [official Ubuntu flavors][6] yet.
|
||||
|
||||
[Reinstalling a new distribution][7] is a bit of annoyances for you would lose the data and you’ll have to reinstall your applications on the newly installed UbuntuDDE.
|
||||
|
||||
A simpler option is to install Deepin desktop environment on your existing Ubuntu system. After all you can easily install more than one [desktop environment][8] in one system.
|
||||
|
||||
Fret not, it is easy to do it and you can also revert the changes if you do not like it. Let me show you how to do that.
|
||||
|
||||
### Installing Deepin Desktop on Ubuntu 20.04
|
||||
|
||||
![][9]
|
||||
|
||||
The UbuntuDDE team has created a PPA for their distribution and you can use the same PPA to install Deepin desktop on Ubuntu 20.04. Keep in mind that this PPA is only available for Ubuntu 20.04. Please read about [using PPA in Ubuntu][10].
|
||||
|
||||
No Deepin version 20
|
||||
|
||||
The Deepin desktop you’ll be installing using the PPA here is NOT the new Deepin desktop version 20 yet. It will probably be there after Ubuntu 20.10 release but we cannot promise anything.
|
||||
|
||||
Here are the steps that you need to follow:
|
||||
|
||||
**Step 1**: You need to first add the [official PPA by Ubuntu DDE Remix team][11] by typing this on the terminal:
|
||||
|
||||
```
|
||||
sudo add-apt-repository ppa:ubuntudde-dev/stable
|
||||
```
|
||||
|
||||
**Step 2**: Once you have added the repository, proceed with installing the Deepin desktop.
|
||||
|
||||
```
|
||||
sudo apt install ubuntudde-dde
|
||||
```
|
||||
|
||||
![][12]
|
||||
|
||||
Now, the installation will start and after a while, you will be asked to choose the display manager.
|
||||
|
||||
![][13]
|
||||
|
||||
You need to select “**lightdm**” if you want Deepin desktop themed lock screen. If not, you can set it as “**gdm3**“.
|
||||
|
||||
In case you don’t see this option, you can get it by typing the following command and then select your preferred display manager:
|
||||
|
||||
```
|
||||
sudo dpkg-reconfigure lightdm
|
||||
```
|
||||
|
||||
**Step 3:** Once done, you have to log out and log in again by choosing the “**Deepin**” session or just reboot the system.
|
||||
|
||||
![][14]
|
||||
|
||||
And, that is it. Enjoy the Deepin experience on your Ubuntu 20.04 LTS system in no time!
|
||||
|
||||
![][15]
|
||||
|
||||
### Removing Deepin desktop from Ubuntu 20.04
|
||||
|
||||
In case, you don’t like the experience or of it is buggy for some reason, you can remove it by following the steps below.
|
||||
|
||||
**Step 1:** If you’ve set “lightdm” as your display manager, you need to set the display manager as “gdm3” before uninstalling Deepin. To do that, type in the following command:
|
||||
|
||||
```
|
||||
sudo dpkg-reconfigure lightdm
|
||||
```
|
||||
|
||||
![Select gdm3 on this screen][13]
|
||||
|
||||
And, select **gdm3** to proceed.
|
||||
|
||||
Once you’re done with that, you can simply enter the following command to remove Deepin completely:
|
||||
|
||||
```
|
||||
sudo apt remove startdde ubuntudde-dde
|
||||
```
|
||||
|
||||
You can just reboot to get back to your original Ubuntu desktop. In case the icons become unresponsive, you just open the terminal (**CTRL + ALT + T**) and type in:
|
||||
|
||||
```
|
||||
reboot
|
||||
```
|
||||
|
||||
**Wrapping Up**
|
||||
|
||||
It is good to have different [choices of desktop environments][16]. If you really like Deepin desktop interface, this could be a way to experience Deepin on Ubuntu.
|
||||
|
||||
If you have questions or if you face any issues, please let me know in the comments.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://itsfoss.com/install-deepin-ubuntu/
|
||||
|
||||
作者：[Ankush Das][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://itsfoss.com/author/ankush/
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://itsfoss.com/beautiful-linux-distributions/
|
||||
[2]: https://itsfoss.com/deepin-20-review/
|
||||
[3]: https://www.deepin.org/en/
|
||||
[4]: https://www.debian.org/
|
||||
[5]: https://itsfoss.com/ubuntudde/
|
||||
[6]: https://itsfoss.com/which-ubuntu-install/
|
||||
[7]: https://itsfoss.com/reinstall-ubuntu/
|
||||
[8]: https://itsfoss.com/what-is-desktop-environment/
|
||||
[9]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2020/10/ubuntu-20-with-deepin.jpg?resize=800%2C386&ssl=1
|
||||
[10]: https://itsfoss.com/ppa-guide/
|
||||
[11]: https://launchpad.net/~ubuntudde-dev/+archive/ubuntu/stable
|
||||
[12]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2020/10/deepin-desktop-install.png?resize=800%2C534&ssl=1
|
||||
[13]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2020/10/deepin-display-manager.jpg?resize=800%2C521&ssl=1
|
||||
[14]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2020/10/deepin-session-ubuntu.jpg?resize=800%2C414&ssl=1
|
||||
[15]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2020/10/ubuntu-20-with-deepin-1.png?resize=800%2C589&ssl=1
|
||||
[16]: https://itsfoss.com/best-linux-desktop-environments/
|
||||
@ -0,0 +1,185 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (How to Remove Physical Volume from a Volume Group in LVM)
|
||||
[#]: via: (https://www.2daygeek.com/linux-remove-delete-physical-volume-pv-from-volume-group-vg-in-lvm/)
|
||||
[#]: author: (Magesh Maruthamuthu https://www.2daygeek.com/author/magesh/)
|
||||
|
||||
How to Remove Physical Volume from a Volume Group in LVM
|
||||
======
|
||||
|
||||
If a device is no longer need for use by LVM, you can use the vgreduce command to remove physical volumes from a volume group.
|
||||
|
||||
The Vgreduce command shrinks the capacity of a volume group by removing a physical volume.
|
||||
|
||||
But make sure that the physical volume is not used by any logical volumes using the pvdisplay command.
|
||||
|
||||
If the physical volume is still being used, you must transfer the data to another physical volume using the pvmove command.
|
||||
|
||||
Once the data is moved, it can be removed from the volume group.
|
||||
|
||||
Finally use the pvremove command to remove the LVM label and LVM metadata on the empty physical volume.
|
||||
|
||||
* **Part-1: [How to Create/Configure LVM (Logical Volume Management) in Linux][1]**
|
||||
* **Part-2: [How to Extend/Increase LVM’s (Logical Volume Resize) in Linux][2]**
|
||||
* **Part-3: [How to Reduce/Shrink LVM’s (Logical Volume Resize) in Linux][3]**
|
||||
|
||||
|
||||
|
||||
![][4]
|
||||
|
||||
### 1) Moving Extents to Existing Physical Volumes
|
||||
|
||||
Use the pvs command to check if the desired physical volume (we plan to remove the **“/dev/sdb1”** disk in LVM) is used or not.
|
||||
|
||||
```
|
||||
# pvs -o+pv_used
|
||||
|
||||
PV VG Fmt Attr PSize PFree Used
|
||||
/dev/sda1 myvg lvm2 a- 75.00G 14.00G 61.00G
|
||||
/dev/sdb1 myvg lvm2 a- 50.00G 45.00G 5.00G
|
||||
/dev/sdc1 myvg lvm2 a- 17.15G 12.15G 5.00G
|
||||
```
|
||||
|
||||
If this is used, check to see if there are enough free extents on the other physics volumes in the volume group.
|
||||
|
||||
If so, you can run the pvmove command on the device you want to remove. Extents will be distributed to other devices.
|
||||
|
||||
```
|
||||
# pvmove /dev/sdb1
|
||||
|
||||
/dev/sdb1: Moved: 2.0%
|
||||
…
|
||||
/dev/sdb1: Moved: 79.2%
|
||||
…
|
||||
/dev/sdb1: Moved: 100.0%
|
||||
```
|
||||
|
||||
When the pvmove command is complete. Re-use the pvs command to check whether the physics volume is free or not.
|
||||
|
||||
```
|
||||
# pvs -o+pv_used
|
||||
|
||||
PV VG Fmt Attr PSize PFree Used
|
||||
/dev/sda1 myvg lvm2 a- 75.00G 9.00G 66.00G
|
||||
/dev/sdb1 myvg lvm2 a- 50.00G 50.00G 0
|
||||
/dev/sdc1 myvg lvm2 a- 17.15G 12.15G 5.00G
|
||||
```
|
||||
|
||||
If it’s free, use the vgreduce command to remove the physical volume /dev/sdb1 from the volume group.
|
||||
|
||||
```
|
||||
# vgreduce myvg /dev/sdb1
|
||||
Removed "/dev/sdb1" from volume group "myvg"
|
||||
```
|
||||
|
||||
Finally, run the pvremove command to remove the disk from the LVM configuration. Now, the disk is completely removed from the LVM and can be used for other purposes.
|
||||
|
||||
```
|
||||
# pvremove /dev/sdb1
|
||||
Labels on physical volume "/dev/sdb1" successfully wiped.
|
||||
```
|
||||
|
||||
### 2) Moving Extents to a New Disk
|
||||
|
||||
If you don’t have enough free extents on the other physics volumes in the volume group. Add new physical volume using the steps below.
|
||||
|
||||
Request new LUNs from the storage team. Once this is allocated, run the following commands to **[discover newly added LUNs or disks in Linux][5]**.
|
||||
|
||||
```
|
||||
# ls /sys/class/scsi_host
|
||||
host0
|
||||
```
|
||||
|
||||
```
|
||||
# echo "- - -" > /sys/class/scsi_host/host0/scan
|
||||
```
|
||||
|
||||
```
|
||||
# fdisk -l
|
||||
```
|
||||
|
||||
Once the disk is detected in the OS, use the pvcreate command to create the physical volume.
|
||||
|
||||
```
|
||||
# pvcreate /dev/sdd1
|
||||
Physical volume "/dev/sdd1" successfully created
|
||||
```
|
||||
|
||||
Use the following command to add new physical volume /dev/sdd1 to the existing volume group vg01.
|
||||
|
||||
```
|
||||
# vgextend vg01 /dev/sdd1
|
||||
Volume group "vg01" successfully extended
|
||||
```
|
||||
|
||||
Now, use the pvs command to see the new disk **“/dev/sdd1”** that you have added.
|
||||
|
||||
```
|
||||
# pvs -o+pv_used
|
||||
|
||||
PV VG Fmt Attr PSize PFree Used
|
||||
/dev/sda1 myvg lvm2 a- 75.00G 14.00G 61.00G
|
||||
/dev/sdb1 myvg lvm2 a- 50.00G 0 50.00G
|
||||
/dev/sdc1 myvg lvm2 a- 17.15G 12.15G 5.00G
|
||||
/dev/sdd1 myvg lvm2 a- 60.00G 60.00G 0
|
||||
```
|
||||
|
||||
Use the pvmove command to move the data from /dev/sdb1 to /dev/sdd1.
|
||||
|
||||
```
|
||||
# pvmove /dev/sdb1 /dev/sdd1
|
||||
|
||||
/dev/sdb1: Moved: 10.0%
|
||||
…
|
||||
/dev/sdb1: Moved: 79.7%
|
||||
…
|
||||
/dev/sdb1: Moved: 100.0%
|
||||
```
|
||||
|
||||
After the data is moved to the new disk. Re-use the pvs command to check whether the physics volume is free.
|
||||
|
||||
```
|
||||
# pvs -o+pv_used
|
||||
|
||||
PV VG Fmt Attr PSize PFree Used
|
||||
/dev/sda1 myvg lvm2 a- 75.00G 14.00G 61.00G
|
||||
/dev/sdb1 myvg lvm2 a- 50.00G 50.00G 0
|
||||
/dev/sdc1 myvg lvm2 a- 17.15G 12.15G 5.00G
|
||||
/dev/sdd1 myvg lvm2 a- 60.00G 10.00G 50.00G
|
||||
```
|
||||
|
||||
If it’s free, use the vgreduce command to remove the physical volume /dev/sdb1 from the volume group.
|
||||
|
||||
```
|
||||
# vgreduce myvg /dev/sdb1
|
||||
Removed "/dev/sdb1" from volume group "myvg"
|
||||
```
|
||||
|
||||
Finally, run the pvremove command to remove the disk from the LVM configuration. Now, the disk is completely removed from the LVM and can be used for other purposes.
|
||||
|
||||
```
|
||||
# pvremove /dev/sdb1
|
||||
Labels on physical volume "/dev/sdb1" successfully wiped.
|
||||
```
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://www.2daygeek.com/linux-remove-delete-physical-volume-pv-from-volume-group-vg-in-lvm/
|
||||
|
||||
作者：[Magesh Maruthamuthu][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://www.2daygeek.com/author/magesh/
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://www.2daygeek.com/create-lvm-storage-logical-volume-manager-in-linux/
|
||||
[2]: https://www.2daygeek.com/extend-increase-resize-lvm-logical-volume-in-linux/
|
||||
[3]: https://www.2daygeek.com/reduce-shrink-decrease-resize-lvm-logical-volume-in-linux/
|
||||
[4]: data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7
|
||||
[5]: https://www.2daygeek.com/scan-detect-luns-scsi-disks-on-redhat-centos-oracle-linux/
|
||||
235
sources/tech/20201009 My open source video game for Open Jam.md
Normal file
235
sources/tech/20201009 My open source video game for Open Jam.md
Normal file
@ -0,0 +1,235 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (My open source video game for Open Jam)
|
||||
[#]: via: (https://opensource.com/article/20/10/open-source-game)
|
||||
[#]: author: (Klaatu https://opensource.com/users/klaatu)
|
||||
|
||||
My open source video game for Open Jam
|
||||
======
|
||||
Step through a game programmed for Open Jam 2020 to get tips for your
|
||||
own design.
|
||||
![Gaming with penguin pawns][1]
|
||||
|
||||
This year, I joined in on the [Open Jam][2], a "game jam" in which programmers around the world dedicate a weekend to create open source games. The jam is essentially an excuse to spend a weekend coding, and the majority of the games that come out of the challenge are small distractions rather than something you're likely to play for hours on end. But they're fun, diverse, and open source, and that's a pretty good feature list for a game.
|
||||
|
||||
The game I submitted is [Unveil][3], a calming puzzle game in which the player must first discover the goal, and then work to achieve it with the greatest number of points. Because part of the game is the discovery process, I won't reveal any more about the gameplay than that.
|
||||
|
||||
![Unveil game][4]
|
||||
|
||||
(Klaatu, [CC BY-SA 4.0][5])
|
||||
|
||||
The whole game is only 338 lines, written in [Python][6] using the [Pygame][6] module. It's, of course, open source, and part of it may serve as a good introduction to a few programming concepts that used to confound me (two-dimensional arrays being the most significant). For simple game design, a two-dimensional array is very useful because so many enduring games are built on them. You can probably think of several, although if you don't know what a two-dimensional array is, you may not realize it.
|
||||
|
||||
### Arrays in gaming
|
||||
|
||||
An array is a collection of data. An array can be listed across a page or an X-axis (in mathematical terms). For instance:
|
||||
|
||||
|
||||
```
|
||||
`artichoke, lettuce, carrot, aubergine, potato`
|
||||
```
|
||||
|
||||
An array may also be represented as a list or a Y-axis:
|
||||
|
||||
|
||||
```
|
||||
artichoke
|
||||
lettuce
|
||||
carrot
|
||||
aubergine
|
||||
potato
|
||||
```
|
||||
|
||||
This is a one-dimensional array. A two-dimensional array extends on both the X-axis and Y-axis.
|
||||
|
||||
Here's a common two-dimensional array seen in the world of board games:
|
||||
|
||||
![Chess][7]
|
||||
|
||||
(Klaatu, [CC BY-SA 4.0][5])
|
||||
|
||||
Yes, two-dimensional arrays are used as the board for chess, draughts, noughts and crosses (also called tic-tac-toe), [RPG battle maps][8], [minesweeper][9], Carcassonne, Forbidden Island, and in slightly modified forms, games like Monopoly and even [Ur][10] (literally the oldest game we know of).
|
||||
|
||||
If you can comfortably create a two-dimensional array, you have a great start at programming any number of games.
|
||||
|
||||
### Creating tiles in Pygame
|
||||
|
||||
If you're not familiar with Python, you should take some time to review this [Python (and Pygame) introductory series][11]. If you feel confident enough to translate code to other libraries, though, there's nothing specific to Pygame in the "important" parts of this code (the array constructor), so you can use any library or language.
|
||||
|
||||
For simplicity, I'll call the individual squares in the game board array _tiles_. To construct a two-dimensional array, or game board as the case may be, you must have tiles. In object-oriented programming, you consider each component as a unique object based upon a template (or _class_, in programming terminology). So, before creating the game board, you must first create the infrastructure for the board's building blocks: tiles.
|
||||
|
||||
First, set up a simple Pygame project, creating a display (your window into the game world), a group to represent the game board, and a few standard variables:
|
||||
|
||||
|
||||
```
|
||||
import pygame
|
||||
|
||||
pygame.init()
|
||||
game_world = pygame.display.set_mode((960, 720))
|
||||
game_board = pygame.sprite.Group()
|
||||
|
||||
running = True
|
||||
black = (0, 0, 0)
|
||||
white = (255, 255, 255)
|
||||
red = (245, 22, 22)
|
||||
world_x = 960
|
||||
world_y = 720
|
||||
```
|
||||
|
||||
Next, create a `Tile` class to establish the template from which each tile gets cast. The first function initializes a new tile when one is created and gives it the necessary basic fields: width, height, an image (actually, I just filled it with the color white), and whether or not it's active. In this case, I use `is_pressed`, as if the tile is a button, because that's what it'll look like when the code is finished: when the user clicks a tile, it changes color as if it were a button being lit up. For other purposes, this state needn't be visible. In chess, for example, you might instead have a field to represent whether a tile is occupied and, if so, by what kind of chess piece.
|
||||
|
||||
|
||||
```
|
||||
class Tile(pygame.sprite.Sprite):
|
||||
def __init__(self, x, y, w, h, c):
|
||||
pygame.sprite.Sprite.__init__(self)
|
||||
self.image = pygame.Surface((w, h))
|
||||
self.image.fill(c)
|
||||
self.rect = self.image.get_rect()
|
||||
self.rect.x = x
|
||||
self.rect.y = y
|
||||
self.is_pressed = False
|
||||
```
|
||||
|
||||
The second function is an update function. Specifically, it checks whether a tile has been clicked by the user. This requires mouse coordinates, which you'll get later in the code during the event loop.
|
||||
|
||||
For this demonstration, I'll make this function fill the tile with the color red when it's in the `is_pressed` state and back to white otherwise:
|
||||
|
||||
|
||||
```
|
||||
def was_clicked(self, mouse):
|
||||
if self.rect.collidepoint(mouse) and not self.is_pressed:
|
||||
self.image.fill(red)
|
||||
self.is_pressed = True
|
||||
elif self.rect.collidepoint(mouse) and self.is_pressed:
|
||||
self.image.fill(white)
|
||||
self.is_pressed = False
|
||||
else:
|
||||
return False
|
||||
```
|
||||
|
||||
### Main loop
|
||||
|
||||
This demo's main loop is simple. It checks for two kinds of input: a quit signal and a mouse down (click) event. When it detects a mouse click, it calls the `was_clicked` function to react (filling it with red or white, depending on its current state).
|
||||
|
||||
Finally, the screen fills with black, the game board state is updated, and the screen is redrawn:
|
||||
|
||||
|
||||
```
|
||||
"""
|
||||
holding place for game board construction
|
||||
"""
|
||||
|
||||
while running:
|
||||
for event in pygame.event.get():
|
||||
if event.type == pygame.QUIT:
|
||||
running = False
|
||||
|
||||
elif event.type == pygame.MOUSEBUTTONDOWN:
|
||||
for hitbox in game_board:
|
||||
hitbox.was_clicked(event.pos)
|
||||
|
||||
game_world.fill(black)
|
||||
game_board.update()
|
||||
game_board.draw(game_world)
|
||||
pygame.display.update()
|
||||
|
||||
pygame.quit()
|
||||
```
|
||||
|
||||
### Board construction
|
||||
|
||||
To build a two-dimensional array, you must first decide how many tiles you want in both directions. I'll use eight for this example because that's how a chessboard is constructed, but you could use fewer or more. You could even accept arguments at launch to define the array's size depending on options, such as `--row` and `--column:`
|
||||
|
||||
|
||||
```
|
||||
rows = 8
|
||||
columns = 8
|
||||
```
|
||||
|
||||
Because you don't know the size of the board, you must calculate the width of the rows and columns based on the size of your display. I also include one pixel of padding between each tile, because, without a gap, it looks like one big block of color:
|
||||
|
||||
|
||||
```
|
||||
column_width = world_x / columns
|
||||
row_height = world_y / rows
|
||||
pad = 1
|
||||
```
|
||||
|
||||
Laying out tiles across the display is simple. Of course, this isn't the goal, as it only draws along the X-axis, but it's a good start:
|
||||
|
||||
|
||||
```
|
||||
j = 0
|
||||
|
||||
while j < rows:
|
||||
tile = Tile(j * column_width, row_height, column_width - pad, row_height - pad, white)
|
||||
game_board.add(tile)
|
||||
j += 1
|
||||
```
|
||||
|
||||
The idea is that the variable `j` starts at 0, so the first tile is placed from 0 to `column_width`, less the value of the padding. Then the variable `j` is incremented to 1, so the next tile is placed at 1 times the value of `column_width`, and so on.
|
||||
|
||||
You can run that code to see the partial success it renders. What this solution obviously lacks is any awareness of further rows.
|
||||
|
||||
Use a second counter variable to track rows:
|
||||
|
||||
|
||||
```
|
||||
j = 0
|
||||
k = 0
|
||||
|
||||
while j < rows:
|
||||
while k < columns:
|
||||
tile = Tile(k * column_width, j * row_height, column_width - pad, row_height - pad, white)
|
||||
game_board.add(tile)
|
||||
k += 1
|
||||
j += 1
|
||||
k = 0
|
||||
```
|
||||
|
||||
In this code block, which achieves the desired result, each tile is positioned in a space determined by the current value of either `j` or `k`.
|
||||
|
||||
The `k` variable is incremented within its loop so that each tile is progressively placed along the X-axis.
|
||||
|
||||
The `j` variable is incremented outside the nested loop so that everything gets moved down one row.
|
||||
|
||||
The `k` variable is then set to 0 so that when the inner loop starts again, everything is shunted back to the far left of the screen.
|
||||
|
||||
![2D array][12]
|
||||
|
||||
(Klaatu, [CC BY-SA 4.0][5])
|
||||
|
||||
### Easy arrays
|
||||
|
||||
Creating a grid can seem mathematically and syntactically intensive, but with this example plus a little bit of thought about what result you want, you can generate them at will. The only thing left for you to do now is to create a game around it. That's what I did, and you're welcome to play it by downloading it from its home on [Itch.io][3] or from its source repository on [git.nixnet.xyz][13]. Enjoy!
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://opensource.com/article/20/10/open-source-game
|
||||
|
||||
作者：[Klaatu][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://opensource.com/users/klaatu
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://opensource.com/sites/default/files/styles/image-full-size/public/lead-images/gaming_grid_penguin.png?itok=7Fv83mHR (Gaming with penguin pawns)
|
||||
[2]: http://openjam.io
|
||||
[3]: https://notklaatu.itch.io/unveil
|
||||
[4]: https://opensource.com/sites/default/files/uploads/unveil-2.jpg (Unveil game)
|
||||
[5]: https://creativecommons.org/licenses/by-sa/4.0/
|
||||
[6]: https://www.python.org/
|
||||
[7]: https://opensource.com/sites/default/files/uploads/chess.jpg (Chess)
|
||||
[8]: https://opensource.com/article/18/5/maptool
|
||||
[9]: https://opensource.com/article/19/9/advanced-bash-building-minesweeper
|
||||
[10]: https://otagomuseum.nz/athome/the-royal-game-of-ur
|
||||
[11]: https://opensource.com/article/17/10/python-101
|
||||
[12]: https://opensource.com/sites/default/files/uploads/2darray.jpg (2D array)
|
||||
[13]: https://git.nixnet.xyz/klaatu/unveil
|
||||
@ -0,0 +1,134 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (6 Essential Things To Do After Installing Manjaro Linux)
|
||||
[#]: via: (https://itsfoss.com/things-to-do-after-installing-manjaro/)
|
||||
[#]: author: (Dimitrios Savvopoulos https://itsfoss.com/author/dimitrios/)
|
||||
|
||||
6 Essential Things To Do After Installing Manjaro Linux
|
||||
======
|
||||
|
||||
So, you just did a [fresh installation of Manjaro Linux][1]. Now what?
|
||||
|
||||
Here are a few essential post installation steps I recommend you to follow.
|
||||
|
||||
Quite honestly, these are the things I prefer to do after installing Manjaro. Yours could differ depending on your need.
|
||||
|
||||
### Recommended Things To Do After Installing Manjaro Linux
|
||||
|
||||
![][2]
|
||||
|
||||
I am using Manjaro Xfce edition but the steps are applicable to other desktop variants of [Manjaro][3] as well.
|
||||
|
||||
#### 1\. Set the fastest mirror
|
||||
|
||||
Before even updating your system, I suggest to sort out your mirror list first. When refreshing the Manjaro system and downloading software from repositories, an optimized mirror list can have noticeable performance impact to the system.
|
||||
|
||||
Open the Terminal emulator and type the following command:
|
||||
|
||||
```
|
||||
sudo pacman-mirrors --fasttrack
|
||||
```
|
||||
|
||||
![][4]
|
||||
|
||||
#### 2\. Update your system
|
||||
|
||||
Keeping your system up-to-date reduces the chances of security vulnerabilities. Refreshing your system repository is also a recommended thing to do before installing new software.
|
||||
|
||||
You can [update your Manjaro system][5] by running the following command.
|
||||
|
||||
```
|
||||
sudo pacman -Syu
|
||||
```
|
||||
|
||||
![][6]
|
||||
|
||||
#### 3\. Enable AUR, Snap or Flatpak support
|
||||
|
||||
[Arch User Repository (AUR)][7] is one of the main reasons that a user chooses an [Arch-based system][8]. It gives you access to a huge number of additional software.
|
||||
|
||||
Optionally, you can also enable support for [Snaps][9] and [Flatpaks][10] directly from Pamac GUI package manager.
|
||||
|
||||
![][11]
|
||||
|
||||
#### 4\. Enable TRIM (SSD only)
|
||||
|
||||
If your root partition has been installed on SSD, enabling [TRIM][12] is one thing you need to do after installing Manjaro. TRIM helps to clean blocks in your SSD and extend the lifespan of your SSD.
|
||||
|
||||
To enable TRIM on Manjaro, run the following command in a terminal:
|
||||
|
||||
```
|
||||
sudo systemctl enable fstrim.timer
|
||||
```
|
||||
|
||||
![][13]
|
||||
|
||||
#### 5\. Installing a kernel of your choice (advanced users)
|
||||
|
||||
One of the topics that I covered in my [Manjaro Linux review][14], is how easily you can switch kernels through a graphical interface.
|
||||
|
||||
Do you prefer to use the command line? You can list the installed kernel(s) on your system and install a kernel using your terminal.
|
||||
|
||||
To list the installed kernels:
|
||||
|
||||
```
|
||||
mhwd-kernel -li
|
||||
```
|
||||
|
||||
**To install a new kernel** (the latest to date 5.8 kernel for example)**:**
|
||||
|
||||
```
|
||||
sudo mhwd-kernel -i linux58
|
||||
```
|
||||
|
||||
![][15]
|
||||
|
||||
#### 6\. Install Microsoft true type fonts (if you need it)
|
||||
|
||||
I have to often edit the work documents on my personal computer and hence I need the Microsoft fonts like Times New Roman or Arial.
|
||||
|
||||
If you also need to use Microsoft fonts, you can access the [package][16] from [AUR][7]. If you want to use the command line for AUR packages, you can install an [AUR helper][17].
|
||||
|
||||
![][18]
|
||||
|
||||
#### Conclusion
|
||||
|
||||
[Manjaro is a great distribution][19] if you want to use the benefits of Arch Linux on a pre-configured, desktop optimized distribution. Though it comes pre-configured with many essentials, there are a few steps that cannot be done in advance, as everyone has a different setup and different needs.
|
||||
|
||||
Please let us know in the comments below, which step apart from the already mentioned is the essential for you.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://itsfoss.com/things-to-do-after-installing-manjaro/
|
||||
|
||||
作者：[Dimitrios Savvopoulos][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://itsfoss.com/author/dimitrios/
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://itsfoss.com/install-manjaro-linux/
|
||||
[2]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2020/10/things-to-do-after-installing-manjaro.jpg?resize=800%2C450&ssl=1
|
||||
[3]: https://manjaro.org
|
||||
[4]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2020/08/manjaro-fasttrack.png?resize=800%2C600&ssl=1
|
||||
[5]: https://itsfoss.com/update-arch-linux/
|
||||
[6]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2020/03/sudo-pacman-Syu.png?resize=800%2C504&ssl=1
|
||||
[7]: https://itsfoss.com/aur-arch-linux/
|
||||
[8]: https://itsfoss.com/arch-based-linux-distros/
|
||||
[9]: https://itsfoss.com/use-snap-packages-ubuntu-16-04/
|
||||
[10]: https://itsfoss.com/flatpak-guide/
|
||||
[11]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2020/08/pamac-2.png?resize=800%2C600&ssl=1
|
||||
[12]: https://en.wikipedia.org/wiki/Trim_(computing)
|
||||
[13]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2020/08/fstrim.timer_.png?resize=800%2C600&ssl=1
|
||||
[14]: https://itsfoss.com/manjaro-linux-review/
|
||||
[15]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2020/08/manjaro-cli-kernels.png?resize=800%2C600&ssl=1
|
||||
[16]: https://aur.archlinux.org/packages/ttf-ms-fonts
|
||||
[17]: https://itsfoss.com/best-aur-helpers/
|
||||
[18]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2020/08/ttf-ms-fonts.png?resize=800%2C600&ssl=1
|
||||
[19]: https://itsfoss.com/why-use-manjaro-linux/
|
||||
@ -0,0 +1,136 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (rakino)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (Things You Didn't Know About GNU Readline)
|
||||
[#]: via: (https://twobithistory.org/2019/08/22/readline.html)
|
||||
[#]: author: (Two-Bit History https://twobithistory.org)
|
||||
|
||||
你所不知的 GNU Readline
|
||||
======
|
||||
|
||||
有时我会觉得自己的计算机是一栋非常大的房子，我每天都会访问这栋房子，也对一楼的大部分房间都了如指掌，但仍然还是有卧室我没有去过，有衣柜我没有打开过，有犄角旮旯我没有探索过。我感到有必要更多地了解我的计算机了，就像任何人都会觉得有必要看看自己家里从未去过的房间一样。
|
||||
|
||||
GNU Readline 是个不起眼的小软件库，我依赖了它多年却没有意识到它的存在，也许有成千上万的人每天都在不经意间使用它。如果你用 Bash shell 的话，每当你补全一个文件名，或者在一行文本输入中移动光标，以及搜索之前命令的历史记录时，你都在使用 GNU Readline；当你在 Postgres（`psql`）或是 Ruby REPL（`irb`）的命令行界面中进行同样的操作时，你依然在使用 GNU Readline。很多软件都依赖 GNU Readline 库来实现用户所期望的功能，不过这些功能是如此的辅助与不显眼，以至于在我看来很少有人会停下来去想它是从哪里来的。
|
||||
|
||||
GNU Readline 最初是自由软件基金会在 20 世纪 80 年代创建的，如今作为每个人的基础计算设施的重要组成部分的它，由一位志愿者维护。
|
||||
|
||||
### 充满特色
|
||||
|
||||
GNU Readline 库的存在，主要是为了用一组通用的按键来增强任何命令行界面，从而使你可以在一行输入中移动和编辑。例如，在 Bash 提示符中按下 `Ctrl-A`，你的光标会跳到行首，而按下 `Ctrl-E` 则会跳到行末；另一个有用的命令是 `Ctrl-U`，它会删除该行中光标之前的所有内容。
|
||||
|
||||
有很长一段时间，我通过反复敲击方向键来在命令行上移动，如今看来这十分尴尬，也不知道为什么，当时的我从来没有想过可以有一种更快的方法。当然了，没有一个熟悉 Vim 或 Emacs 这种文本编辑器的程序员愿意长时间地击打方向键，所以像 Readline 这样的东西必然会被创造出来；不过在 Readline 上可以做的绝非仅仅跳来跳去，你可以像使用文本编辑器那样编辑单行文本——这里有删除单词、换位、大写单词、复制和粘贴字符等命令。Readline 的大部分按键/快捷键都是基于 Emacs 的，它基本上就是一个单行文本版的 Emacs 了，甚至还有录制和重放宏的功能。
|
||||
|
||||
我从来没有用过 Emacs，所以很难记住所有不同的 Readline 命令。不过 Readline 有着很巧妙的一点，那就是能够切换到基于 Vim 的模式，在 Bash 中可以使用内置的 `set` 命令来这样做。下面会让 Readline 在当前的 shell 中使用 Vim 风格的命令：
|
||||
|
||||
```
|
||||
$ set -o vi
|
||||
```
|
||||
|
||||
该选项启用后，就可以使用 `dw` 等命令来删除单词了，此时相当于 Emacs 模式下的 `Ctrl-U` 的命令是 `d0`。
|
||||
|
||||
我第一次知道有这个功能的时候很兴奋地想尝试一下，但它对我来说并不是那么好用。我很高兴知道有这种对 Vim 用户的让步，在使用这个功能上你可能会比我更幸运，尤其是你还没有使用 Readline 的默认按键的话；我的问题在于，我听说有基于 Vim 的界面时已经学会了几种默认按键，因此即使启用了 Vim 的选项，也一直在错误地用着默认的按键；另外因为没有某种指示器，所以 Vim 的多模态设计在这里会很尴尬——你很容易就忘记了自己处于哪个模式，就因为这样，我卡在了一种虽然使用 Vim 作为文本编辑器，但却在 Readline 上用着 Emacs 风格的命令的情况里，我猜其他很多人也是这样的。
|
||||
|
||||
如果你觉得 Vim 和 Emacs 的键盘命令系统诡异而神秘，你可以按照喜欢的方式自定义 Readline 的键绑定，这并不难。Readline 在启动时会读取文件 `~/.inputrc`，它可以用来配置各种选项与键绑定，我做的一件事是重新配置了 `Ctrl-K`：通常情况下该命令会从光标处删除到行末，但我很少这样做，所以我在 `~/.inputrc` 中添加了以下内容，把它绑定为直接删除整行：
|
||||
|
||||
```
|
||||
Control-k: kill-whole-line
|
||||
```
|
||||
|
||||
每个 Readline 命令（文档中称它们为 _函数_ ）都有一个名称，你可以用这种方式将其与一个键序联系起来。如果你在 Vim 中编辑 `~/.inputrc`，就会发现 Vim 知道这种文件类型，还会帮你高亮显示有效的函数名，而不高亮无效的函数名。
|
||||
|
||||
`~/.inputrc` 可以做的另一件事是通过将键序映射到输入字符串上来创建预制宏。[Readline 手册][1]给出了一个我认为特别有用的例子：我经常想把一个程序的输出保存到文件中，这意味着我得经常在 Bash 命令中追加类似 `> output.txt` 这样的东西，为了节省时间，可以把它做成一个 Readline 宏。
|
||||
|
||||
```
|
||||
Control-o: "> output.txt"
|
||||
```
|
||||
|
||||
这样每当你按下 `Ctrl-O` 时，你都会看到 `> output.txt` 被添加到了命令行光标的后面，这样很不错！
|
||||
|
||||
不过你可以用宏做的可不仅仅是为文本串创建快捷方式；在 `~/.inputrc` 中使用以下条目意味着每次按下 `Ctrl-J` 时，行内已有的文本都会被 `$(` 和 `)` 包裹住。该宏先用 `Ctrl-A` 移动到行首，添加 `$(` ，然后再用 `Ctrl-E` 移动到行尾，添加 `)`。
|
||||
|
||||
```
|
||||
Control-j: "\C-a$(\C-e)"
|
||||
```
|
||||
|
||||
如果你经常需要像下面这样把一个命令的输出用于另一个命令的话，这个宏可能会对你有帮助。
|
||||
|
||||
```
|
||||
$ cd $(brew --prefix)
|
||||
```
|
||||
|
||||
`~/.inputrc` 文件也允许你为 Readline 手册中所谓的 _变量_ 设置不同的值，这些变量会启用或禁用某些 Readline 行为，你也可以使用这些变量来改变 Readline 中像是自动补全或者历史搜索这些行为的工作方式。我建议开启的一个变量是 `revert-all-at-newline`，它是默认关闭的，当这个变量关闭时，如果你使用反向搜索功能从命令历史记录中提取一行并编辑，但随后又决定搜索另一行，那么你所做的编辑会被保存在历史记录中。我觉得这样会很混乱，因为这会导致你的 Bash 命令历史中出现从未运行过的行。所以在你的 `~/.inputrc` 中加入这个：
|
||||
|
||||
```
|
||||
set revert-all-at-newline on
|
||||
```
|
||||
|
||||
在你用 `~/.inputrc` 设置了选项或键绑定以后，它们会适用于任何使用 Readline 库的地方，显然 Bash 包括在内，不过你也会在其它像是 `irb` 和 `psql` 这样的程序中受益。如果你经常使用关系型数据库的命令行界面，一个用于插入 `SELECT * FROM` 的 Readline 宏可能会很有用。
|
||||
|
||||
### Chet Ramey
|
||||
|
||||
GNU Readline 如今由凯斯西储大学的高级技术架构师 Chet Ramey 维护，Ramey 同时还负责维护 Bash shell；这两个项目都是由一位名叫 Brian Fox 的自由软件基金会员工在 1988 年开始编写的，但从 1994 年左右开始，Ramey 一直是它们唯一的维护者。
|
||||
|
||||
Ramey 通过电子邮件告诉我，Readline 远非一个原创的想法，它是为了实现 POSIX 规范所规定的功能而被创建的，而 POSIX 规范又是在 20 世纪 80 年代末被制定的。许多早期的 shell，包括 Korn shell 和至少一个版本的 Unix System V shell，都包含行编辑功能。1988 年版的 Korn shell（`ksh88`）提供了 Emacs 风格和 Vi/Vim 风格的编辑模式。据我从[手册页][2]中得知，Korn shell 会通过查看 `VISUAL` 和 `EDITOR` 环境变量来决定你使用的模式，这一点非常巧妙。POSIX 中指定 shell 功能的部分近似于 `ksh88` 的实现，所以 GNU Bash 也要实现一个类似的灵活的行编辑系统来保持兼容，因此就有了Readline。
|
||||
|
||||
Ramey 第一次参与 Bash 开发时，Readline 还是 Bash 项目目录下的一个源文件，它真的只是 Bash 的一部分；随着时间的推移，Readline 文件慢慢地成为了独立的项目，不过还要等到 1994 年（Readline 的 2.0 版本）Readline 才完全成为了一个独立的库。
|
||||
|
||||
Readline 与 Bash 密切相关，Ramey 也通常把 Readline 与 Bash 的发布配对，但正如我上面提到的，Readline 是一个可以被任何有命令行接口的软件使用的库，而且它真的很容易使用。下面是一个例子，虽然简单，但这就是在 C 程序中使用 Readline 的方法。向 `readline()` 函数传递的字符串参数就是你希望 Readline 向用户显示的提示符：
|
||||
|
||||
```
|
||||
#include <stdio.h>
|
||||
#include <stdlib.h>
|
||||
#include "readline/readline.h"
|
||||
|
||||
int main(int argc, char** argv)
|
||||
{
|
||||
char* line = readline("my-rl-example> ");
|
||||
printf("You entered: \"%s\"\n", line);
|
||||
|
||||
free(line);
|
||||
|
||||
return 0;
|
||||
}
|
||||
```
|
||||
|
||||
你的程序会把控制权交给 Readline，它会负责从用户那里获得一行输入（以这样的方式让用户可以做所有花哨的行编辑工作），一旦用户真正提交了这一行，Readline 就会把它返回给你。在我的库搜索路径中有 Readline 库，所以我可以通过调用以下内容来链接 Readline 库，从而编译上面的内容：
|
||||
|
||||
```
|
||||
$ gcc main.c -lreadline
|
||||
```
|
||||
|
||||
当然，Readline 的 API 比起那个单一的函数要丰富得多，任何使用它的人都可以对库的行为进行各种调整，库的用户（开发者）甚至可以添加新的函数，来让最终用户可以通过 `~/.inputrc` 来配置它们，这意味着 Readline 非常容易扩展。但是据我所知，即使是 Bash ，虽然事先有很多配置，最终也会像上面的例子一样调用简单的 `readline()` 函数来获取输入。（参见 GNU Bash 源代码中的[这一行][3]，Bash 似乎在这里将获取输入的责任交给了 Readline）。
|
||||
|
||||
Ramey 现在已经在 Bash 和 Readline 上工作了十多年，但他的工作却从来没有得到过报酬——他一直都是一名志愿者。尽管 Ramey 说 Readline 的变化比 Bash 慢得多，但 Bash 和 Readline 仍然在积极开发中。我问 Ramey 作为这么多人使用的软件唯一的维护者是什么感觉，他说可能有几百万人在不知不觉中使用 Bash（因为每个苹果设备都运行 Bash），这让他担心一个突破性的变化会造成多大的破坏，不过他已经慢慢习惯了所有这些人的想法。他还说他会继续在 Bash 和 Readline 上工作，因为在这一点上他已经深深地投入了，而且他也只是单纯地喜欢把有用的软件提供给世界。
|
||||
|
||||
_你可以在 [Chet Ramey 的网站][4]上找到更多关于他的信息。_
|
||||
|
||||
_喜欢这篇文章吗？我会每四周写出一篇像这样的文章。关注推特帐号 [@TwoBitHistory][5] 或者[订阅 RSS][6] 来获取更新吧！_
|
||||
|
||||
_TwoBitHistory 的上一条消息：_
|
||||
|
||||
> 请欣赏我拖欠已久的新文章，我在里面以 BBC Micro 和计算机认知计划的故事作为出发点抱怨了一下 Codecademy。<https://t.co/PiWlKljDjK>
|
||||
>
|
||||
> — TwoBitHistory (@TwoBitHistory) [三月 31，2019][7]
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://twobithistory.org/2019/08/22/readline.html
|
||||
|
||||
作者：[Two-Bit History][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[rakino](https://github.com/rakino)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://twobithistory.org
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://tiswww.case.edu/php/chet/readline/readline.html
|
||||
[2]: https://web.archive.org/web/20151105130220/http://www2.research.att.com/sw/download/man/man1/ksh88.html
|
||||
[3]: https://github.com/bminor/bash/blob/9f597fd10993313262cab400bf3c46ffb3f6fd1e/parse.y#L1487
|
||||
[4]: https://tiswww.case.edu/php/chet/
|
||||
[5]: https://twitter.com/TwoBitHistory
|
||||
[6]: https://twobithistory.org/feed.xml
|
||||
[7]: https://twitter.com/TwoBitHistory/status/1112492084383092738?ref_src=twsrc%5Etfw
|
||||
@ -1,5 +1,5 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: translator: (gxlct008)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
@ -7,25 +7,23 @@
|
||||
[#]: via: (https://nicolasparada.netlify.com/posts/go-messenger-access-page/)
|
||||
[#]: author: (Nicolás Parada https://nicolasparada.netlify.com/)
|
||||
|
||||
Building a Messenger App: Access Page
|
||||
构建一个即时消息应用（七）：Access 页面
|
||||
======
|
||||
|
||||
This post is the 7th on a series:
|
||||
本文是该系列的第七篇。
|
||||
|
||||
* [Part 1: Schema][1]
|
||||
* [Part 2: OAuth][2]
|
||||
* [Part 3: Conversations][3]
|
||||
* [Part 4: Messages][4]
|
||||
* [Part 5: Realtime Messages][5]
|
||||
* [Part 6: Development Login][6]
|
||||
* [第一篇: 模式][1]
|
||||
* [第二篇: OAuth][2]
|
||||
* [第三篇: 对话][3]
|
||||
* [第四篇: 消息][4]
|
||||
* [第五篇: 实时消息][5]
|
||||
* [第六篇: 仅用于开发的登录][6]
|
||||
|
||||
现在我们已经完成了后端，让我们转到前端。 我将采用单页应用程序方案。
|
||||
|
||||
首先，我们创建一个 `static/index.html` 文件，内容如下。
|
||||
|
||||
Now that we’re done with the backend, lets move to the frontend. I will go with a single-page application.
|
||||
|
||||
Lets start by creating a file `static/index.html` with the following content.
|
||||
|
||||
```
|
||||
```html
|
||||
<!DOCTYPE html>
|
||||
<html lang="en">
|
||||
<head>
|
||||
@ -40,11 +38,11 @@ Lets start by creating a file `static/index.html` with the following content.
|
||||
</html>
|
||||
```
|
||||
|
||||
This HTML file must be server for every URL and JavaScript will take care of rendering the correct page.
|
||||
这个 HTML 文件必须为每个 URL 提供服务，并且将使用 JavaScript 负责呈现正确的页面。
|
||||
|
||||
So lets go the the `main.go` for a moment and in the `main()` function add the following route:
|
||||
因此，让我们将注意力转到 `main.go` 片刻，然后在 `main()` 函数中添加以下路由：
|
||||
|
||||
```
|
||||
```go
|
||||
router.Handle("GET", "/...", http.FileServer(SPAFileSystem{http.Dir("static")}))
|
||||
|
||||
type SPAFileSystem struct {
|
||||
@ -60,15 +58,15 @@ func (spa SPAFileSystem) Open(name string) (http.File, error) {
|
||||
}
|
||||
```
|
||||
|
||||
We use a custom file system so instead of returning `404 Not Found` for unknown URLs, it serves the `index.html`.
|
||||
我们使用一个自定义的文件系统，因此它不是为未知的 URL 返回 `404 Not Found`，而是转到 `index.html`。
|
||||
|
||||
### Router
|
||||
### 路由器
|
||||
|
||||
In the `index.html` we loaded two files: `styles.css` and `main.js`. I leave styling to your taste.
|
||||
在 `index.html` 中我们加载了两个文件：`styles.css` 和 `main.js`。我把样式留给你自由发挥。
|
||||
|
||||
Lets move to `main.js`. Create a `static/main.js` file with the following content:
|
||||
让我们移动到 `main.js`。 创建一个包含以下内容的 `static/main.js` 文件：
|
||||
|
||||
```
|
||||
```javascript
|
||||
import { guard } from './auth.js'
|
||||
import Router from './router.js'
|
||||
|
||||
@ -98,19 +96,22 @@ function view(pageName) {
|
||||
}
|
||||
```
|
||||
|
||||
If you are follower of this blog, you already know how this works. That router is the one showed [here][7]. Just download it from [@nicolasparada/router][8] and save it to `static/router.js`.
|
||||
如果您是这个博客的关注者，您已经知道它是如何工作的了。 该路由器就是在 [这里][7] 显示的那个。 只需从 [@nicolasparada/router][8] 下载并保存到 `static/router.js` 即可。
|
||||
|
||||
We registered four routes. At the root `/` we show the home or access page whether the user is authenticated. At `/callback` we show the callback page. On `/conversations/{conversationID}` we show the conversation or access page whether the user is authenticated and for every other URL, we show a not found page.
|
||||
|
||||
We tell the router to render the result to the document body and dispatch a `disconnect` event to each page before leaving.
|
||||
我们注册了四条路由。 在根路由 `/` 处，我们展示 home 或 access 页面，无论用户是否通过身份验证。 在 `/callback` 中，我们展示 callback 页面。 在 `/conversations/{conversationID}` 上，我们展示对话或 access 页面，无论用户是否通过验证，对于其他 URL，我们展示一个 not found 页面。
|
||||
|
||||
We have each page in a different file and we import them with the new dynamic `import()`.
|
||||
我们告诉路由器将结果渲染为文档主体，并在离开之前向每个页面调度一个 `disconnect` 事件。
|
||||
|
||||
### Auth
|
||||
我们将每个页面放在不同的文件中，并使用新的动态 `import()` 函数导入它们。
|
||||
|
||||
`guard()` is a function that given two functions, executes the first one if the user is authenticated, or the sencond one if not. It comes from `auth.js` so lets create a `static/auth.js` file with the following content:
|
||||
### 身份验证
|
||||
|
||||
```
|
||||
`guard()` 是一个函数，给它两个函数作为参数，如果用户通过了身份验证，则执行第一个函数，否则执行第二个。
|
||||
它来自 `auth.js`，所以我们创建一个包含以下内容的 `static/auth.js` 文件：
|
||||
|
||||
```javascript
|
||||
export function isAuthenticated() {
|
||||
const token = localStorage.getItem('token')
|
||||
const expiresAtItem = localStorage.getItem('expires_at')
|
||||
@ -150,17 +151,17 @@ export function getAuthUser() {
|
||||
}
|
||||
```
|
||||
|
||||
`isAuthenticated()` checks for `token` and `expires_at` from localStorage to tell if the user is authenticated. `getAuthUser()` gets the authenticated user from localStorage.
|
||||
`isAuthenticated()` 检查 localStorage 中的 `token` 和 `expires_at`，以判断用户是否已通过身份验证。`getAuthUser()` 从 localStorage 中获取经过身份验证的用户。
|
||||
|
||||
When we login, we’ll save all the data to localStorage so it will make sense.
|
||||
当我们登录时，我们会将所有的数据保存到 localStorage，这样才有意义。
|
||||
|
||||
### Access Page
|
||||
### Access 页面
|
||||
|
||||
![access page screenshot][9]
|
||||
|
||||
Lets start with the access page. Create a file `static/pages/access-page.js` with the following content:
|
||||
让我们从 access 页面开始。 创建一个包含以下内容的文件 `static/pages/access-page.js`：
|
||||
|
||||
```
|
||||
```javascript
|
||||
const template = document.createElement('template')
|
||||
template.innerHTML = `
|
||||
<h1>Messenger</h1>
|
||||
@ -172,15 +173,15 @@ export default function accessPage() {
|
||||
}
|
||||
```
|
||||
|
||||
Because the router intercepts all the link clicks to do its navigation, we must prevent the event propagation for this link in particular.
|
||||
因为路由器会拦截所有链接点击来进行导航，所以我们必须特别阻止此链接的事件传播。
|
||||
|
||||
Clicking on that link will redirect us to the backend, then to GitHub, then to the backend and then to the frontend again; to the callback page.
|
||||
单击该链接会将我们重定向到后端，然后重定向到 GitHub，再重定向到后端，然后再次重定向到前端； 到 callback 页面。
|
||||
|
||||
### Callback Page
|
||||
### Callback 页面
|
||||
|
||||
Create the file `static/pages/callback-page.js` with the following content:
|
||||
创建包括以下内容的 `static/pages/callback-page.js` 文件：
|
||||
|
||||
```
|
||||
```javascript
|
||||
import http from '../http.js'
|
||||
import { navigate } from '../router.js'
|
||||
|
||||
@ -211,13 +212,13 @@ function getAuthUser(token) {
|
||||
}
|
||||
```
|
||||
|
||||
The callback page doesn’t render anything. It’s an async function that does a GET request to `/api/auth_user` using the token from the URL query string and saves all the data to localStorage. Then it redirects to `/`.
|
||||
callback 页面不呈现任何内容。这是一个异步函数，它使用 URL 查询字符串中的 token 向 `/api/auth_user` 发出 GET 请求，并将所有数据保存到 localStorage。 然后重定向到 `/`。
|
||||
|
||||
### HTTP
|
||||
|
||||
There is an HTTP module. Create a `static/http.js` file with the following content:
|
||||
这里是一个 HTTP 模块。 创建一个包含以下内容的 `static/http.js` 文件：
|
||||
|
||||
```
|
||||
```javascript
|
||||
import { isAuthenticated } from './auth.js'
|
||||
|
||||
async function handleResponse(res) {
|
||||
@ -297,15 +298,15 @@ export default {
|
||||
}
|
||||
```
|
||||
|
||||
This module is a wrapper around the [fetch][10] and [EventSource][11] APIs. The most important part is that it adds the JSON web token to the requests.
|
||||
这个模块是 [fetch][10] 和 [EventSource][11] API 的包装器。最重要的部分是它将 JSON web 令牌添加到请求中。
|
||||
|
||||
### Home Page
|
||||
### Home 页面
|
||||
|
||||
![home page screenshot][12]
|
||||
|
||||
So, when the user login, the home page will be shown. Create a `static/pages/home-page.js` file with the following content:
|
||||
因此，当用户登录时，将显示主页。 创建一个具有以下内容的 `static/pages/home-page.js` 文件：
|
||||
|
||||
```
|
||||
```javascript
|
||||
import { getAuthUser } from '../auth.js'
|
||||
import { avatar } from '../shared.js'
|
||||
|
||||
@ -334,15 +335,15 @@ function onLogoutClick() {
|
||||
}
|
||||
```
|
||||
|
||||
For this post, this is the only content we render on the home page. We show the current authenticated user and a logout button.
|
||||
对于这篇文章，这是我们在主页上呈现的唯一内容。我们显示当前经过身份验证的用户和注销按钮。
|
||||
|
||||
When the user clicks to logout, we clear all inside localStorage and do a reload of the page.
|
||||
当用户单击注销时，我们清除 localStorage 中的所有内容并重新加载页面。
|
||||
|
||||
### Avatar
|
||||
|
||||
That `avatar()` function is to show the user’s avatar. Because it’s used in more than one place, I moved it to a `shared.js` file. Create the file `static/shared.js` with the following content:
|
||||
那个 `avatar()` 函数用于显示用户的头像。 由于已在多个地方使用，因此我将它移到 `shared.js` 文件中。 创建具有以下内容的文件 `static/shared.js`：
|
||||
|
||||
```
|
||||
```javascript
|
||||
export function avatar(user) {
|
||||
return user.avatarUrl === null
|
||||
? `<figure class="avatar" data-initial="${user.username[0]}"></figure>`
|
||||
@ -351,22 +352,24 @@ export function avatar(user) {
|
||||
```
|
||||
|
||||
We use a small figure with the user’s initial in case the avatar URL is null.
|
||||
如果头像网址为 null，我们将使用用户的姓名首字母作为初始头像。
|
||||
|
||||
您可以使用 `attr()` 函数显示带有少量 CSS 样式的首字母。
|
||||
You can show the initial with a little of CSS using the `attr()` function.
|
||||
|
||||
```
|
||||
```css
|
||||
.avatar[data-initial]::after {
|
||||
content: attr(data-initial);
|
||||
}
|
||||
```
|
||||
|
||||
### Development Login
|
||||
### 仅开发使用的登录
|
||||
|
||||
![access page with login form screenshot][13]
|
||||
|
||||
In the previous post we coded a login for development. Lets add a form for that in the access page. Go to `static/pages/access-page.js` and modify it a little.
|
||||
在上一篇文章中，我们为编写了一个登录代码。让我们在 access 页面中为此添加一个表单。 进入 `static/ages/access-page.js`，稍微修改一下。
|
||||
|
||||
```
|
||||
```javascript
|
||||
import http from '../http.js'
|
||||
|
||||
const template = document.createElement('template')
|
||||
@ -420,13 +423,13 @@ function login(username) {
|
||||
}
|
||||
```
|
||||
|
||||
I added a login form. When the user submits the form. It does a POST requets to `/api/login` with the username. Saves all the data to localStorage and reloads the page.
|
||||
我添加了一个登录表单。当用户提交表单时。它使用用户名对 `/api/login` 进行 POST 请求。将所有数据保存到 localStorage 并重新加载页面。
|
||||
|
||||
Remember to remove this form once you are done with the frontend.
|
||||
记住在前端完成后删除此表单。
|
||||
|
||||
* * *
|
||||
|
||||
That’s all for this post. In the next one, we’ll continue with the home page to add a form to start conversations and display a list with the latest ones.
|
||||
这就是这篇文章的全部内容。在下一篇文章中，我们将继续使用主页添加一个表单来开始对话，并显示包含最新对话的列表。
|
||||
|
||||
[Souce Code][14]
|
||||
|
||||
@ -436,7 +439,7 @@ via: https://nicolasparada.netlify.com/posts/go-messenger-access-page/
|
||||
|
||||
作者：[Nicolás Parada][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
译者：[译者ID](https://github.com/gxlct008)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
@ -1,5 +1,5 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: translator: (gxlct008)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
@ -7,44 +7,43 @@
|
||||
[#]: via: (https://nicolasparada.netlify.com/posts/go-messenger-home-page/)
|
||||
[#]: author: (Nicolás Parada https://nicolasparada.netlify.com/)
|
||||
|
||||
Building a Messenger App: Home Page
|
||||
构建一个即时消息应用（八）：Home 页面
|
||||
======
|
||||
|
||||
This post is the 8th on a series:
|
||||
本文是该系列的第八篇。
|
||||
|
||||
* [Part 1: Schema][1]
|
||||
* [Part 2: OAuth][2]
|
||||
* [Part 3: Conversations][3]
|
||||
* [Part 4: Messages][4]
|
||||
* [Part 5: Realtime Messages][5]
|
||||
* [Part 6: Development Login][6]
|
||||
* [Part 7: Access Page][7]
|
||||
* [第一篇: 模式][1]
|
||||
* [第二篇: OAuth][2]
|
||||
* [第三篇: 对话][3]
|
||||
* [第四篇: 消息][4]
|
||||
* [第五篇: 实时消息][5]
|
||||
* [第六篇: 仅用于开发的登录][6]
|
||||
* [第七篇: Access 页面][7]
|
||||
|
||||
|
||||
继续前端部分，让我们在本文中完成 Home 页面的开发。 我们将添加一个开始对话的表单和一个包含最新对话的列表。
|
||||
|
||||
Continuing the frontend, let’s finish the home page in this post. We’ll add a form to start conversations and a list with the latest ones.
|
||||
|
||||
### Conversation Form
|
||||
### 对话表单
|
||||
|
||||
![conversation form screenshot][8]
|
||||
|
||||
In the `static/pages/home-page.js` file add some markup in the HTML view.
|
||||
转到 `static/ages/home-page.js` 文件，在 HTML 视图中添加一些标记。
|
||||
|
||||
```
|
||||
```html
|
||||
<form id="conversation-form">
|
||||
<input type="search" placeholder="Start conversation with..." required>
|
||||
</form>
|
||||
```
|
||||
|
||||
Add that form just below the section in which we displayed the auth user and logout button.
|
||||
将该表单添加到我们显示 auth user 和 logout 按钮部分的下方。
|
||||
|
||||
```
|
||||
```js
|
||||
page.getElementById('conversation-form').onsubmit = onConversationSubmit
|
||||
```
|
||||
|
||||
Now we can listen to the “submit” event to create the conversation.
|
||||
现在我们可以监听 “submit” 事件来创建对话了。
|
||||
|
||||
```
|
||||
```js
|
||||
import http from '../http.js'
|
||||
import { navigate } from '../router.js'
|
||||
|
||||
@ -79,15 +78,15 @@ function createConversation(username) {
|
||||
}
|
||||
```
|
||||
|
||||
On submit we do a POST request to `/api/conversations` with the username and redirect to the conversation page (for the next post).
|
||||
在提交时，我们使用用户名对 `/api/conversations` 进行 POST 请求，并重定向到 conversation 页面 (用于下一篇文章)。
|
||||
|
||||
### Conversation List
|
||||
### 对话列表
|
||||
|
||||
![conversation list screenshot][9]
|
||||
|
||||
In the same file, we are going to make the `homePage()` function async to load the conversations first.
|
||||
还是在这个文件中，我们将创建 `homePage()` 函数用来先异步加载对话。
|
||||
|
||||
```
|
||||
```js
|
||||
export default async function homePage() {
|
||||
const conversations = await getConversations().catch(err => {
|
||||
console.error(err)
|
||||
@ -101,24 +100,24 @@ function getConversations() {
|
||||
}
|
||||
```
|
||||
|
||||
Then, add a list in the markup to render conversations there.
|
||||
然后，在标记中添加一个列表来渲染对话。
|
||||
|
||||
```
|
||||
```html
|
||||
<ol id="conversations"></ol>
|
||||
```
|
||||
|
||||
Add it just below the current markup.
|
||||
将其添加到当前标记的正下方。
|
||||
|
||||
```
|
||||
```js
|
||||
const conversationsOList = page.getElementById('conversations')
|
||||
for (const conversation of conversations) {
|
||||
conversationsOList.appendChild(renderConversation(conversation))
|
||||
}
|
||||
```
|
||||
|
||||
So we can append each conversation to the list.
|
||||
因此，我们可以将每个对话添加到这个列表中。
|
||||
|
||||
```
|
||||
```js
|
||||
import { avatar, escapeHTML } from '../shared.js'
|
||||
|
||||
function renderConversation(conversation) {
|
||||
@ -146,11 +145,11 @@ function renderConversation(conversation) {
|
||||
}
|
||||
```
|
||||
|
||||
Each conversation item contains a link to the conversation page and displays the other participant info and a preview of the last message. Also, you can use `.hasUnreadMessages` to add a class to the item and do some styling with CSS. Maybe a bolder font or accent the color.
|
||||
每个对话条目都包含一个指向对话页面的链接，并显示其他参与者信息和最后一条消息的预览。另外，您可以使用 `.hasUnreadMessages` 向该条目添加一个类，并使用 CSS 进行一些样式设置。也许是粗体字体或强调颜色。
|
||||
|
||||
Note that we’re escaping the message content. That function comes from `static/shared.js`:
|
||||
请注意，我们需要转义信息的内容。该函数来自于 `static/shared.js` 文件：
|
||||
|
||||
```
|
||||
```js
|
||||
export function escapeHTML(str) {
|
||||
return str
|
||||
.replace(/&/g, '&')
|
||||
@ -161,35 +160,35 @@ export function escapeHTML(str) {
|
||||
}
|
||||
```
|
||||
|
||||
That prevents displaying as HTML the message the user wrote. If the user happens to write something like:
|
||||
这会阻止将用户编写的消息显示为 HTML。如果用户碰巧编写了类似以下内容的代码：
|
||||
|
||||
```
|
||||
```js
|
||||
<script>alert('lololo')</script>
|
||||
```
|
||||
|
||||
It would be very annoying because that script will be executed 😅
|
||||
So yeah, always remember to escape content from untrusted sources.
|
||||
这将非常烦人，因为该脚本将被执行😅。
|
||||
所以，永远记住要转义来自不可信来源的内容。
|
||||
|
||||
### Messages Subscription
|
||||
### 消息订阅
|
||||
|
||||
Last but not least, I want to subscribe to the message stream here.
|
||||
最后但并非最不重要的一点，我想在这里订阅消息流。
|
||||
|
||||
```
|
||||
```js
|
||||
const unsubscribe = subscribeToMessages(onMessageArrive)
|
||||
page.addEventListener('disconnect', unsubscribe)
|
||||
```
|
||||
|
||||
Add that line in the `homePage()` function.
|
||||
在 `homePage()` 函数中添加这一行。
|
||||
|
||||
```
|
||||
```js
|
||||
function subscribeToMessages(cb) {
|
||||
return http.subscribe('/api/messages', cb)
|
||||
}
|
||||
```
|
||||
|
||||
The `subscribe()` function returns a function that once called it closes the underlying connection. That’s why I passed it to the “disconnect” event; so when the user leaves the page, the event stream will be closed.
|
||||
函数 `subscribe()` 返回一个函数，该函数一旦调用就会关闭底层连接。这就是为什么我把它传递给 <ruby>“断开连接”<rt>disconnect</rt></ruby>事件的原因；因此，当用户离开页面时，事件流将被关闭。
|
||||
|
||||
```
|
||||
```js
|
||||
async function onMessageArrive(message) {
|
||||
const conversationLI = document.querySelector(`li[data-id="${message.conversationID}"]`)
|
||||
if (conversationLI !== null) {
|
||||
@ -221,12 +220,12 @@ function getConversation(id) {
|
||||
}
|
||||
```
|
||||
|
||||
Every time a new message arrives, we go and query for the conversation item in the DOM. If found, we add the `has-unread-messages` class to the item, and update the view. If not found, it means the message is from a new conversation created just now. We go and do a GET request to `/api/conversations/{conversationID}` to get the conversation in which the message was created and prepend it to the conversation list.
|
||||
每次有新消息到达时，我们都会在 DOM 中查询会话条目。如果找到，我们会将 `has-unread-messages` 类添加到该条目中，并更新视图。如果未找到，则表示该消息来自刚刚创建的新对话。我们去做一个对 `/api/conversations/{conversationID}` 的 GET 请求，以获取在其中创建消息的对话，并将其放在对话列表的前面。
|
||||
|
||||
* * *
|
||||
|
||||
That covers the home page 😊
|
||||
On the next post we’ll code the conversation page.
|
||||
以上这些涵盖了主页的所有内容 😊。
|
||||
在下一篇文章中，我们将对 conversation 页面进行编码。
|
||||
|
||||
[Souce Code][10]
|
||||
|
||||
@ -236,7 +235,7 @@ via: https://nicolasparada.netlify.com/posts/go-messenger-home-page/
|
||||
|
||||
作者：[Nicolás Parada][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
译者：[译者ID](https://github.com/gxlct008)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
@ -1,5 +1,5 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: ( )
|
||||
[#]: translator: (gxlct008)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
@ -7,31 +7,31 @@
|
||||
[#]: via: (https://nicolasparada.netlify.com/posts/go-messenger-conversation-page/)
|
||||
[#]: author: (Nicolás Parada https://nicolasparada.netlify.com/)
|
||||
|
||||
Building a Messenger App: Conversation Page
|
||||
构建一个即时消息应用（九）：Conversation 页面
|
||||
======
|
||||
|
||||
This post is the 9th and last in a series:
|
||||
本文是该系列的第九篇，也是最后一篇。
|
||||
|
||||
* [Part 1: Schema][1]
|
||||
* [Part 2: OAuth][2]
|
||||
* [Part 3: Conversations][3]
|
||||
* [Part 4: Messages][4]
|
||||
* [Part 5: Realtime Messages][5]
|
||||
* [Part 6: Development Login][6]
|
||||
* [Part 7: Access Page][7]
|
||||
* [Part 8: Home Page][8]
|
||||
* [第一篇: 模式][1]
|
||||
* [第二篇: OAuth][2]
|
||||
* [第三篇: 对话][3]
|
||||
* [第四篇: 消息][4]
|
||||
* [第五篇: 实时消息][5]
|
||||
* [第六篇: 仅用于开发的登录][6]
|
||||
* [第七篇: Access 页面][7]
|
||||
* [第八篇: Home 页面][8]
|
||||
|
||||
|
||||
|
||||
In this post we’ll code the conversation page. This page is the chat between the two users. At the top we’ll show info about the other participant, below, a list of the latest messages and a message form at the bottom.
|
||||
在这篇文章中，我们将对<ruby>对话<rt>conversation</rt></ruby>页面进行编码。此页面是两个用户之间的聊天室。在顶部我们将显示其他参与者的信息，下面接着的是最新消息列表，以及底部的消息表单。
|
||||
|
||||
### Chat heading
|
||||
### 聊天标题
|
||||
|
||||
![chat heading screenshot][9]
|
||||
|
||||
Let’s start by creating the file `static/pages/conversation-page.js` with the following content:
|
||||
让我们从创建 `static/pages/conversation-page.js` 文件开始，它包含以下内容:
|
||||
|
||||
```
|
||||
```js
|
||||
import http from '../http.js'
|
||||
import { navigate } from '../router.js'
|
||||
import { avatar, escapeHTML } from '../shared.js'
|
||||
@ -65,17 +65,17 @@ function getConversation(id) {
|
||||
}
|
||||
```
|
||||
|
||||
This page receives the conversation ID the router extracted from the URL.
|
||||
此页面接收路由从 URL 中提取的会话 ID。
|
||||
|
||||
First it does a GET request to `/api/conversations/{conversationID}` to get info about the conversation. In case of error, we show it and redirect back to `/`. Then we render info about the other participant.
|
||||
首先，它向 `/api/ conversations/{conversationID}` 发起一个 GET 请求，以获取有关对话的信息。 如果出现错误，我们会将其显示，并重定向回 `/`。然后我们呈现有关其他参与者的信息。
|
||||
|
||||
### Conversation List
|
||||
### 对话列表
|
||||
|
||||
![chat heading screenshot][10]
|
||||
|
||||
We’ll fetch the latest messages too to display them.
|
||||
我们也会获取最新的消息并显示它们。
|
||||
|
||||
```
|
||||
```js
|
||||
let conversation, messages
|
||||
try {
|
||||
[conversation, messages] = await Promise.all([
|
||||
@ -85,32 +85,32 @@ try {
|
||||
}
|
||||
```
|
||||
|
||||
Update the `conversationPage()` function to fetch the messages too. We use `Promise.all()` to do both request at the same time.
|
||||
更新 `conversationPage()` 函数以获取消息。我们使用 `Promise.all()` 同时执行这两个请求。
|
||||
|
||||
```
|
||||
```js
|
||||
function getMessages(conversationID) {
|
||||
return http.get(`/api/conversations/${conversationID}/messages`)
|
||||
}
|
||||
```
|
||||
|
||||
A GET request to `/api/conversations/{conversationID}/messages` gets the latest messages of the conversation.
|
||||
发起对 `/api/conversations/{conversationID}/messages` 的 GET 请求可以获取对话中的最新消息。
|
||||
|
||||
```
|
||||
```html
|
||||
<ol id="messages"></ol>
|
||||
```
|
||||
|
||||
Now, add that list to the markup.
|
||||
现在，将该列表添加到标记中。
|
||||
|
||||
```
|
||||
```js
|
||||
const messagesOList = page.getElementById('messages')
|
||||
for (const message of messages.reverse()) {
|
||||
messagesOList.appendChild(renderMessage(message))
|
||||
}
|
||||
```
|
||||
|
||||
So we can append messages to the list. We show them in reverse order.
|
||||
这样我们就可以将消息附加到列表中了。我们以时间倒序来显示它们。
|
||||
|
||||
```
|
||||
```js
|
||||
function renderMessage(message) {
|
||||
const messageContent = escapeHTML(message.content)
|
||||
const messageDate = new Date(message.createdAt).toLocaleString()
|
||||
@ -127,28 +127,28 @@ function renderMessage(message) {
|
||||
}
|
||||
```
|
||||
|
||||
Each message item displays the message content itself with its timestamp. Using `.mine` we can append a different class to the item so maybe you can show the message to the right.
|
||||
每个消息条目显示消息内容本身及其时间戳。使用 `.mine`，我们可以将不同的 css 类附加到条目，这样您就可以将消息显示在右侧。
|
||||
|
||||
### Message Form
|
||||
### 消息表单
|
||||
|
||||
![chat heading screenshot][11]
|
||||
|
||||
```
|
||||
```html
|
||||
<form id="message-form">
|
||||
<input type="text" placeholder="Type something" maxlength="480" required>
|
||||
<button>Send</button>
|
||||
</form>
|
||||
```
|
||||
|
||||
Add that form to the current markup.
|
||||
将该表单添加到当前标记中。
|
||||
|
||||
```
|
||||
```js
|
||||
page.getElementById('message-form').onsubmit = messageSubmitter(conversationID)
|
||||
```
|
||||
|
||||
Attach an event listener to the “submit” event.
|
||||
将事件监听器附加到 “submit” 事件。
|
||||
|
||||
```
|
||||
```js
|
||||
function messageSubmitter(conversationID) {
|
||||
return async ev => {
|
||||
ev.preventDefault()
|
||||
@ -191,19 +191,20 @@ function createMessage(content, conversationID) {
|
||||
}
|
||||
```
|
||||
|
||||
We make use of [partial application][12] to have the conversation ID in the “submit” event handler. It takes the message content from the input and does a POST request to `/api/conversations/{conversationID}/messages` with it. Then prepends the newly created message to the list.
|
||||
|
||||
### Messages Subscription
|
||||
我们利用 [partial application][12] 在 “submit” 事件处理程序中获取对话 ID。它 从输入中获取消息内容，并用它对 `/api/conversations/{conversationID}/messages` 发出 POST 请求。 然后将新创建的消息添加到列表中。
|
||||
|
||||
To make it realtime we’ll subscribe to the message stream in this page also.
|
||||
### 消息订阅
|
||||
|
||||
```
|
||||
为了实现实时，我们还将订阅此页面中的消息流。
|
||||
|
||||
```js
|
||||
page.addEventListener('disconnect', subscribeToMessages(messageArriver(conversationID)))
|
||||
```
|
||||
|
||||
Add that line in the `conversationPage()` function.
|
||||
将该行添加到 `conversationPage()` 函数中。
|
||||
|
||||
```
|
||||
```js
|
||||
function subscribeToMessages(cb) {
|
||||
return http.subscribe('/api/messages', cb)
|
||||
}
|
||||
@ -229,14 +230,14 @@ function readMessages(conversationID) {
|
||||
}
|
||||
```
|
||||
|
||||
We also make use of partial application to have the conversation ID here.
|
||||
When a new message arrives, first we check if it’s from this conversation. If it is, we go a prepend a message item to the list and do a POST request to `/api/conversations/{conversationID}/read_messages` to updated the last time the participant read messages.
|
||||
在这里我们仍然使用 partial application 来获取会话 ID。
|
||||
当新消息到达时，我们首先检查它是否来自此对话。如果是，我们会将消息条目预先添加到列表中，并向`/api/conversations/{conversationID}/read_messages`发起 POST 一个请求，以更新参与者上次阅读消息的时间。
|
||||
|
||||
* * *
|
||||
|
||||
That concludes this series. The messenger app is now functional.
|
||||
本系列到此结束。 Messenger app 现在可以运行了。
|
||||
|
||||
~~I’ll add pagination on the conversation and message list, also user searching before sharing the source code. I’ll updated once it’s ready along with a hosted demo 👨💻~~
|
||||
~~我将在对话和消息列表中添加分页功能，并在共享源代码之前添加用户搜索。我会在准备好的时候和<ruby>托管的演示<rt>a hosted demo</rt></ruby>👨💻一起更新它~~
|
||||
|
||||
[Souce Code][13] • [Demo][14]
|
||||
|
||||
@ -246,7 +247,7 @@ via: https://nicolasparada.netlify.com/posts/go-messenger-conversation-page/
|
||||
|
||||
作者：[Nicolás Parada][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
译者：[gxlct008](https://github.com/gxlct008)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
@ -0,0 +1,273 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (gxlct008)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (Using Yarn on Ubuntu and Other Linux Distributions)
|
||||
[#]: via: (https://itsfoss.com/install-yarn-ubuntu)
|
||||
[#]: author: (Abhishek Prakash https://itsfoss.com/author/abhishek/)
|
||||
|
||||
在 Ubuntu 和其他 Linux 发行版上使用 Yarn
|
||||
======
|
||||
|
||||
***本速成教程向您展示了在 Ubuntu 和 Debian Linux 上安装 Yarn 包管理器的官方方法。您还将学习到一些基本的 Yarn 命令以及彻底删除 Yarn 的步骤。***
|
||||
|
||||
[Yarn][1] 是 Facebook 开发的开源 JavaScript 包管理器。它是流行的 npm 包管理器的一个替代品，或者应该说是改进。 [Facebook 开发团队][2] 创建 Yarn 是为了克服 [npm][3] 的缺点。 Facebook 声称 Yarn 比 npm 更快、更可靠、更安全。
|
||||
|
||||
与 npm 一样，Yarn 为您提供一种自动安装、更新、配置和删除从全局注册表中检索到的程序包的方法。
|
||||
|
||||
Yarn 的优点是它更快，因为它缓存了已下载的每个包，所以无需再次下载。它还将操作并行化，以最大化资源利用率。在执行每个已安装的包代码之前，Yarn 还使用 [校验和来验证完整性][4]。 Yarn 还保证在一个系统上运行的安装，在任何其他系统上都会以完全相同地方式工作。
|
||||
|
||||
如果您正 [在 Ubuntu 上使用 nodejs][5]，那么您的系统上可能已经安装了 npm。在这种情况下，您可以通过以下方式使用 npm 全局安装 Yarn：
|
||||
|
||||
```
|
||||
sudo npm install yarn -g
|
||||
```
|
||||
|
||||
不过，我推荐使用官方方式在 Ubuntu/Debian 上安装 Yarn。
|
||||
|
||||
### 在 Ubuntu 和 Debian 上安装 Yarn [官方方式]
|
||||
|
||||
![Yarn JS][6]
|
||||
|
||||
这里提到的指令应该适用于所有版本的 Ubuntu，例如 Ubuntu 18.04、16.04 等。同样的指令集也适用于 Debian 和其他基于 Debian 的发行版。
|
||||
|
||||
由于本教程使用 curl 来添加 Yarn 项目的 GPG 密钥，所以最好验证一下您是否已经安装了 curl。
|
||||
|
||||
```
|
||||
sudo apt install curl
|
||||
```
|
||||
|
||||
如果 curl 尚未安装，则上面的命令将安装它。既然有了 curl，您就可以使用它以如下方式添加 Yarn 项目的 GPG 密钥：
|
||||
|
||||
```
|
||||
curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | sudo apt-key add -
|
||||
```
|
||||
|
||||
在此之后，将存储库添加到源列表中，以便将来可以轻松地升级 Yarn 包，并进行其余系统更新：
|
||||
|
||||
```
|
||||
sudo sh -c 'echo "deb https://dl.yarnpkg.com/debian/ stable main" >> /etc/apt/sources.list.d/yarn.list'
|
||||
```
|
||||
|
||||
您现在可以继续了。[更新 Ubuntu][7] 或 Debian 系统，以刷新可用软件包列表，然后安装 Yarn：
|
||||
|
||||
```
|
||||
sudo apt update
|
||||
sudo apt install yarn
|
||||
```
|
||||
|
||||
这将一起安装 Yarn 和 nodejs。该过程完成后，请验证是否已成功安装 Yarn。 您可以通过检查 Yarn 版本来做到这一点。
|
||||
|
||||
```
|
||||
yarn --version
|
||||
```
|
||||
|
||||
对我来说，它显示了这样的输出：
|
||||
|
||||
```
|
||||
yarn --version
|
||||
1.12.3
|
||||
```
|
||||
|
||||
这意味着我的系统上安装了 Yarn 版本 1.12.3。
|
||||
|
||||
### 使用 Yarn
|
||||
|
||||
我假设您对 JavaScript 编程以及依赖项的工作原理有一些基本的了解。我在这里不做详细介绍。我将向您展示一些基本的 Yarn 命令，这些命令将帮助您入门。
|
||||
|
||||
#### 使用 Yarn 创建一个新项目
|
||||
|
||||
与 npm 一样，Yarn 也可以使用 package.json 文件。在这里添加依赖项。所有依赖包都缓存在项目根目录下的 node_modules 目录中。
|
||||
|
||||
在项目的根目录中，运行以下命令以生成新的 package.json 文件：
|
||||
|
||||
它会问您一些问题。您可以按 Enter 跳过或使用默认值。
|
||||
|
||||
```
|
||||
yarn init
|
||||
yarn init v1.12.3
|
||||
question name (test_yarn): test_yarn_proect
|
||||
question version (1.0.0): 0.1
|
||||
question description: Test Yarn
|
||||
question entry point (index.js):
|
||||
question repository url:
|
||||
question author: abhishek
|
||||
question license (MIT):
|
||||
question private:
|
||||
success Saved package.json
|
||||
Done in 82.42s.
|
||||
```
|
||||
|
||||
这样，您就得到了一个如下的 package.json 文件：
|
||||
|
||||
```
|
||||
{
|
||||
"name": "test_yarn_proect",
|
||||
"version": "0.1",
|
||||
"description": "Test Yarn",
|
||||
"main": "index.js",
|
||||
"author": "abhishek",
|
||||
"license": "MIT"
|
||||
}
|
||||
```
|
||||
|
||||
现在您有了 package.json，您可以手动编辑它以添加或删除包依赖项，也可以使用 Yarn 命令(首选)。
|
||||
|
||||
#### 使用 Yarn 添加依赖项
|
||||
|
||||
您可以通过以下方式添加对特定包的依赖关系：
|
||||
|
||||
```
|
||||
yarn add <package_name>
|
||||
```
|
||||
|
||||
例如，如果您想在项目中使用 [Lodash][8]，则可以使用 Yarn 添加它，如下所示：
|
||||
|
||||
```
|
||||
yarn add lodash
|
||||
yarn add v1.12.3
|
||||
info No lockfile found.
|
||||
[1/4] Resolving packages…
|
||||
[2/4] Fetching packages…
|
||||
[3/4] Linking dependencies…
|
||||
[4/4] Building fresh packages…
|
||||
success Saved lockfile.
|
||||
success Saved 1 new dependency.
|
||||
info Direct dependencies
|
||||
└─ [email protected]
|
||||
info All dependencies
|
||||
└─ [email protected]
|
||||
Done in 2.67s.
|
||||
```
|
||||
|
||||
您可以看到，此依赖项已自动添加到 package.json 文件中：
|
||||
|
||||
```
|
||||
{
|
||||
"name": "test_yarn_proect",
|
||||
"version": "0.1",
|
||||
"description": "Test Yarn",
|
||||
"main": "index.js",
|
||||
"author": "abhishek",
|
||||
"license": "MIT",
|
||||
"dependencies": {
|
||||
"lodash": "^4.17.11"
|
||||
}
|
||||
}
|
||||
```
|
||||
|
||||
默认情况下，Yarn 将在依赖项中添加最新版本的包。如果要使用特定版本，可以在添加时指定。
|
||||
|
||||
```
|
||||
yarn add package@version-or-tag
|
||||
```
|
||||
|
||||
像往常一样，您也可以手动更新 package.json 文件。
|
||||
|
||||
#### 使用 Yarn 升级依赖项
|
||||
|
||||
您可以使用以下命令将特定依赖项升级到其最新版本：
|
||||
|
||||
```
|
||||
yarn upgrade <package_name>
|
||||
```
|
||||
|
||||
它将查看所涉及的包是否具有较新的版本，并且会相应地对其进行更新。
|
||||
|
||||
您还可以通过以下方式更改已添加的依赖项的版本：
|
||||
|
||||
```
|
||||
yarn upgrade package_name@version_or_tag
|
||||
```
|
||||
|
||||
您还可以使用一个命令将项目的所有依赖项升级到它们的最新版本：
|
||||
|
||||
```
|
||||
yarn upgrade
|
||||
```
|
||||
|
||||
它将检查所有依赖项的版本，如果有任何较新的版本，则会更新它们。
|
||||
|
||||
#### 使用 Yarn 删除依赖项
|
||||
|
||||
您可以通过以下方式从项目的依赖项中删除包：
|
||||
|
||||
```
|
||||
yarn remove <package_name>
|
||||
```
|
||||
|
||||
#### 安装所有项目依赖项
|
||||
|
||||
如果对您 project.json 文件进行了任何更改，则应该运行
|
||||
|
||||
```
|
||||
yarn
|
||||
```
|
||||
|
||||
或者
|
||||
|
||||
```
|
||||
yarn install
|
||||
```
|
||||
|
||||
一次安装所有依赖项。
|
||||
|
||||
### 如何从 Ubuntu 或 Debian 中删除 Yarn
|
||||
|
||||
我将通过介绍从系统中删除 Yarn 的步骤来完成本教程，如果您使用上述步骤安装 Yarn 的话。如果您意识到不再需要 Yarn 了，则可以将它删除。
|
||||
|
||||
使用以下命令删除 Yarn 及其依赖项。
|
||||
|
||||
```
|
||||
sudo apt purge yarn
|
||||
```
|
||||
|
||||
您也应该从源列表中把存储库信息一并删除掉：
|
||||
|
||||
```
|
||||
sudo rm /etc/apt/sources.list.d/yarn.list
|
||||
```
|
||||
|
||||
下一步删除已添加到受信任密钥的 GPG 密钥是可选的。但要做到这一点，您需要知道密钥。您可以使用 `apt-key` 命令获得它：
|
||||
|
||||
```
|
||||
Warning: apt-key output should not be parsed (stdout is not a terminal) pub rsa4096 2016-10-05 [SC] 72EC F46A 56B4 AD39 C907 BBB7 1646 B01B 86E5 0310 uid [ unknown] Yarn Packaging yarn@dan.cx sub rsa4096 2016-10-05 [E] sub rsa4096 2019-01-02 [S] [expires: 2020-02-02]
|
||||
```
|
||||
|
||||
这里的密钥是以 pub 开始的行中 GPG 密钥指纹的最后 8 个字符。
|
||||
|
||||
因此，对于我来说，密钥是 `86E50310`，我将使用以下命令将其删除：
|
||||
|
||||
```
|
||||
sudo apt-key del 86E50310
|
||||
```
|
||||
|
||||
您会在输出中看到 OK，并且 Yarn 包的 GPG 密钥将从系统信任的 GPG 密钥列表中删除。
|
||||
|
||||
我希望本教程可以帮助您在 Ubuntu、Debian、Linux Mint、 elementary OS 等操作系统上安装 Yarn。 我提供了一些基本的 Yarn 命令，以帮助您入门，并完成了从系统中删除 Yarn 的完整步骤。
|
||||
|
||||
希望您喜欢本教程，如果有任何疑问或建议，请随时在下面留言。
|
||||
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://itsfoss.com/install-yarn-ubuntu
|
||||
|
||||
作者：[Abhishek Prakash][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[gxlct008](https://github.com/gxlct008)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://itsfoss.com/author/abhishek/
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://yarnpkg.com/lang/en/
|
||||
[2]: https://code.fb.com/
|
||||
[3]: https://www.npmjs.com/
|
||||
[4]: https://itsfoss.com/checksum-tools-guide-linux/
|
||||
[5]: https://itsfoss.com/install-nodejs-ubuntu/
|
||||
[6]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2019/01/yarn-js-ubuntu-debian.jpeg?resize=800%2C450&ssl=1
|
||||
[7]: https://itsfoss.com/update-ubuntu/
|
||||
[8]: https://lodash.com/
|
||||
@ -7,17 +7,17 @@
|
||||
[#]: via: (https://opensource.com/article/20/6/bash-trap)
|
||||
[#]: author: (Seth Kenlon https://opensource.com/users/seth)
|
||||
|
||||
Using Bash traps in your scripts
|
||||
在脚本中使用 Bash 信号捕获
|
||||
======
|
||||
Traps help your scripts end cleanly, whether they run successfully or
|
||||
not.
|
||||
> 无论你的脚本是否成功运行，<ruby>信号捕获<rt>trap</rt></ruby>都能让它平稳结束。
|
||||
|
||||
![Hands programming][1]
|
||||
|
||||
It's easy to detect when a shell script starts, but it's not always easy to know when it stops. A script might end normally, just as its author intends it to end, but it could also fail due to an unexpected fatal error. Sometimes it's beneficial to preserve the remnants of whatever was in progress when a script failed, and other times it's inconvenient. Either way, detecting the end of a script and reacting to it in some pre-calculated manner is why the [Bash][2] `trap` directive exists.
|
||||
Shell 脚本的启动并不难被检测到，但 Shell 脚本的终止检测却并不容易，因为我们无法确定脚本会按照预期地正常结束，还是由于意外的错误导致失败。当脚本执行失败时，将正在处理的内容记录下来是非常有用的做法，但有时候这样做起来并不方便。而 [Bash][2] 中 `trap` 命令的存在正是为了解决这个问题，它可以捕获到脚本的终止信号，并以某种预设的方式作出应对。
|
||||
|
||||
### Responding to failure
|
||||
### 响应失败
|
||||
|
||||
Here's an example of how one failure in a script can lead to future failures. Say you have written a program that creates a temporary directory in `/tmp` so that it can unarchive and process files before bundling them back together in a different format:
|
||||
如果出现了一个错误，可能导致发生一连串错误。下面示例脚本中，首先在 `/tmp` 中创建一个临时目录，这样可以在临时目录中执行解包、文件处理等操作，然后再以另一种压缩格式进行打包：
|
||||
|
||||
|
||||
```
|
||||
@ -49,13 +49,13 @@ bzip2 --compress $TMP/"${1%.*}".tar \
|
||||
/usr/bin/rm -r /tmp/tmpdir
|
||||
```
|
||||
|
||||
Most of the time, the script works as expected. However, if you accidentally run it on an archive filled with PNG files instead of the expected JPEG files, it fails halfway through. One failure leads to another, and eventually, the script exits without reaching its final directive to remove the temporary directory. As long as you manually remove the directory, you can recover quickly, but if you aren't around to do that, then the next time the script runs, it has to deal with an existing temporary directory full of unpredictable leftover files.
|
||||
一般情况下，这个脚本都可以按照预期执行。但如果归档文件中的文件是 PNG 文件而不是期望的 JPEG 文件，脚本就会在中途失败，这时候另一个问题就出现了：最后一步删除临时目录的操作没有被正常执行。如果你手动把临时目录删掉，倒是不会造成什么影响，但是如果没有手动把临时目录删掉，在下一次执行这个脚本的时候，就会在一个残留着很多临时文件的临时目录里执行了。
|
||||
|
||||
One way to combat this is to reverse and double-up on the logic by adding a precautionary removal to the start of the script. While valid, that relies on brute force instead of structure. A more elegant solution is `trap`.
|
||||
其中一个解决方案是在脚本开头增加一个预防性删除逻辑用来处理这种情况。但这种做法显得有些暴力，而我们更应该从结构上解决这个问题。使用 `trap` 是一个优雅的方法。
|
||||
|
||||
### Catching signals with trap
|
||||
### 使用 `trap` 捕获信号
|
||||
|
||||
The `trap` keyword catches _signals_ that may happen during execution. You've used one of these signals if you've ever used the `kill` or `killall` commands, which call `SIGTERM` by default. There are many other signals that shells respond to, and you can see most of them with `trap -l` (as in "list"):
|
||||
我们可以通过 `trap` 捕捉程序运行时的信号。如果你使用过 `kill` 或者 `killall` 命令，那你就已经使用过名为 `SIGTERM` 的信号了。除此以外，还可以执行 `trap -l` 或 `trap --list` 命令列出其它更多的信号：
|
||||
|
||||
|
||||
```
|
||||
@ -75,24 +75,22 @@ $ trap --list
|
||||
63) SIGRTMAX-1 64) SIGRTMAX
|
||||
```
|
||||
|
||||
Any of these signals may be anticipated with `trap`. In addition to these, `trap` recognizes:
|
||||
可以被 `trap` 识别的信号除了以上这些，还包括：
|
||||
|
||||
* `EXIT`: Occurs when a process exits
|
||||
* `ERR`: Occurs when a process exits with a non-zero status
|
||||
* `DEBUG`: A Boolean representing debug mode
|
||||
* `EXIT`：进程退出时发出的信号
|
||||
* `ERR`：进程以非 0 状态码退出时发出的信号
|
||||
* `DEBUG`：表示调试模式的布尔值
|
||||
|
||||
如果要在 Bash 中实现信号捕获，只需要在 `trap` 后加上需要执行的命令，再加上需要捕获的信号列表就可以了。
|
||||
|
||||
|
||||
To set a trap in Bash, use `trap` followed by a list of commands you want to be executed, followed by a list of signals to trigger it.
|
||||
|
||||
For instance, this trap detects a `SIGINT`, the signal sent when a user presses **Ctrl+C** while a process is running:
|
||||
例如，下面的这行语句可以捕获到在进程运行时用户按下 `Ctrl + C` 组合键发出的 `SIGINT` 信号：
|
||||
|
||||
|
||||
```
|
||||
`trap "{ echo 'Terminated with Ctrl+C'; }" SIGINT`
|
||||
```
|
||||
|
||||
The example script with temporary directory problems can be fixed with a trap detecting `SIGINT`, errors, and successful exits:
|
||||
因此，上文中脚本的缺陷可以通过使用 `trap` 捕获 `SIGINT`、`SIGTERM`、进程错误退出、进程正常退出等信号，并正确处理临时目录的方式来修复：
|
||||
|
||||
|
||||
```
|
||||
@ -123,11 +121,11 @@ bzip2 --compress $TMP/"${1%.*}".tar \
|
||||
--stdout > "${1%.*}".tbz
|
||||
```
|
||||
|
||||
For complex actions, you can simplify `trap` statements with [Bash functions][3].
|
||||
对于更复杂的功能，还可以用 [Bash 函数][3]来简化 `trap` 语句。
|
||||
|
||||
### Traps in Bash
|
||||
### Bash 中的信号捕获
|
||||
|
||||
Traps are useful to ensure that your scripts end cleanly, whether they run successfully or not. It's never safe to rely completely on automated garbage collection, so this is a good habit to get into in general. Try using them in your scripts, and see what they can do!
|
||||
信号捕获可以让脚本在无论是否成功执行所有任务的情况下都能够正确完成清理工作，能让你的脚本更加可靠，这是一个很好的习惯。尽管尝试把信号捕获加入到你的脚本里看看能够起到什么作用吧。
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
@ -135,7 +133,7 @@ via: https://opensource.com/article/20/6/bash-trap
|
||||
|
||||
作者：[Seth Kenlon][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[译者ID](https://github.com/译者ID)
|
||||
译者：[HankChow](https://github.com/HankChow)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
@ -0,0 +1,89 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (geekpi)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (How to Use the Firefox Task Manager (to Find and Kill RAM and CPU Eating Tabs and Extensions))
|
||||
[#]: via: (https://itsfoss.com/firefox-task-manager/)
|
||||
[#]: author: (Ankush Das https://itsfoss.com/author/ankush/)
|
||||
|
||||
如何使用 Firefox 任务管理器（查找并杀死占用内存和 CPU 的标签页和扩展程序）
|
||||
======
|
||||
|
||||
Firefox 在 Linux 用户中很受欢迎。它是几个 Linux 发行版上的默认网络浏览器。
|
||||
|
||||
在许多其他功能中，Firefox 提供了一个自己的任务管理器。
|
||||
|
||||
现在，在 Linux 中既然你有[任务管理器][1]这种形式的[系统监控工具][2]，为什么还要使用它呢？这是有一个很好的理由。
|
||||
|
||||
假设你的系统占用了太多的内存或 CPU。如果你使用 top 或其他一些系统[资源监控工具，如 Glances][3]，你会发现这些工具无法区分打开的标签或扩展。
|
||||
|
||||
通常情况下，每个 Firefox 标签页都显示为 **Web 内容**。你可以看到是某个 Firefox 进程导致了这个问题，但这无法准确判断是哪个标签页或扩展。
|
||||
|
||||
这时你可以使用 Firefox 任务管理器。让我来告诉你怎么做！
|
||||
|
||||
### Firefox 任务管理器
|
||||
|
||||
有了 Firefox 任务管理器，你就可以列出所有消耗系统资源的标签页、跟踪器和附加组件。
|
||||
|
||||
![][4]
|
||||
|
||||
正如你在上面的截图中所看到的，你会看到标签页的名称、类型（标签或附加组件）、能源影响和消耗的内存。
|
||||
|
||||
虽然一切都明了，但**能源影响指的是 CPU 的使用**，如果你使用的是笔记本电脑，它是一个很好的指标，可以告诉你什么东西会更快耗尽电池。
|
||||
|
||||
#### 在 Firefox 中访问任务管理器
|
||||
|
||||
令人意外的是，任务管理器没有 [Firefox 键盘快捷键][5]。
|
||||
|
||||
要快速启动 Firefox 任务管理器，可以在地址栏中输入“**about:performance**”，如下图所示。
|
||||
|
||||
![Quickly access task manager in Firefox][6]
|
||||
|
||||
另外，你也可以点击**菜单**图标，然后进入“**更多**“选项，如下截图所示。
|
||||
|
||||
![Accessing task manager in Firefox][7]
|
||||
|
||||
接下来，你会发现选择”**任务管理器**”的选项，只需点击它就行。
|
||||
|
||||
![][8]
|
||||
|
||||
#### 使用 Firefox 任务管理器
|
||||
|
||||
到这后，你可以检查资源的使用情况，展开标签页来查看跟踪器和它的使用情况，也可以选择关闭标签，如下截图高亮所示。
|
||||
|
||||
![][9]
|
||||
|
||||
以下是你应该知道的：
|
||||
|
||||
* 能源影响指的是 CPU 消耗。
|
||||
* 子框架或子任务通常是与需要在后台运行的标签相关联的跟踪器/脚本。
|
||||
|
||||
|
||||
|
||||
通过这个任务管理器，你可以发现网站上的流氓脚本，以及它是否导致你的浏览器变慢。
|
||||
|
||||
这并不是什么火箭科学，但并不是很多人都知道 Firefox 任务管理器。现在你知道了，它应该很方便，你觉得呢？
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://itsfoss.com/firefox-task-manager/
|
||||
|
||||
作者：[Ankush Das][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[geekpi](https://github.com/geekpi)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://itsfoss.com/author/ankush/
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://itsfoss.com/task-manager-linux/
|
||||
[2]: https://itsfoss.com/linux-system-monitoring-tools/
|
||||
[3]: https://itsfoss.com/glances/
|
||||
[4]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2020/09/firefox-task-manager-shot.png?resize=800%2C519&ssl=1
|
||||
[5]: https://itsfoss.com/firefox-keyboard-shortcuts/
|
||||
[6]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2020/09/firefox-url-performance.jpg?resize=800%2C357&ssl=1
|
||||
[7]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2020/09/firefox-task-manager-steps.jpg?resize=800%2C779&ssl=1
|
||||
[8]: https://i2.wp.com/itsfoss.com/wp-content/uploads/2020/09/firefox-task-manager-menu.jpg?resize=800%2C465&ssl=1
|
||||
[9]: https://i1.wp.com/itsfoss.com/wp-content/uploads/2020/09/firefox-task-manager-close-tab.png?resize=800%2C496&ssl=1
|
||||
@ -0,0 +1,119 @@
|
||||
[#]: collector: (lujun9972)
|
||||
[#]: translator: (geekpi)
|
||||
[#]: reviewer: ( )
|
||||
[#]: publisher: ( )
|
||||
[#]: url: ( )
|
||||
[#]: subject: (Drawing is an Open Source MS-Paint Type of App for Linux Desktop)
|
||||
[#]: via: (https://itsfoss.com/drawing-app/)
|
||||
[#]: author: (Abhishek Prakash https://itsfoss.com/author/abhishek/)
|
||||
|
||||
Drawing 是一款开源的类似微软画图的 Linux 桌面应用
|
||||
======
|
||||
|
||||
_**简介：Drawing 是一个基本的图像编辑器，就像微软画图一样。有了这个开源的应用，你可以画箭头、线条、几何图形、添加颜色和其他你期望在普通绘图应用程序中做的事情。**_
|
||||
|
||||
### Drawing: 一个简单的 Linux 绘图应用
|
||||
|
||||
![][1]
|
||||
|
||||
对于从 Windows XP （或更早版本）开始使用电脑的人来说，微软画图是一个有趣的随机画一些草图的应用。在这个被 Photoshop 和 GIMP 主导的世界里，画图应用仍然具有一定的现实意义。
|
||||
|
||||
有几个[可用于 Linux 的绘画应用][2]，我打算在这个列表中再添加一个。
|
||||
|
||||
这款应用不出意外地叫做 [Drawing][3]，你可以在 Linux 桌面和 Linux 智能手机上使用它。
|
||||
|
||||
### Drawing 应用的功能
|
||||
|
||||
![][4]
|
||||
|
||||
Drawing 拥有你所期待的绘图应用的所有功能。你可以：
|
||||
|
||||
* 从头开始创建新的绘图
|
||||
* 编辑现有的 PNG、JPEG 或 BMP 图像文件。
|
||||
* 添加几何图形、线条、箭头等。
|
||||
* 虚线
|
||||
* 使用铅笔工具进行自由手绘。
|
||||
* 使用曲线和形状工具
|
||||
* 裁剪图像
|
||||
* 缩放图像到不同的像素大小
|
||||
* 添加文本
|
||||
* 选择图像的一部分（矩形、自由选择和颜色选择）。
|
||||
* 旋转图像
|
||||
* 添加复制到剪贴板的图像
|
||||
* 可在偏好中使用橡皮擦、荧光笔、油漆桶、颜色选择、颜色选择器工具
|
||||
* 无限撤销
|
||||
* 滤镜可以增加模糊、像素化、透明度等。
|
||||
|
||||
|
||||
|
||||
### 我使用 Drawing 的经验
|
||||
|
||||
![][5]
|
||||
|
||||
这个应用是新的，并且有不错的用户界面。它具有你期望在标准绘画应用中找到的所有基本功能。
|
||||
|
||||
它有一些额外的工具，如颜色选择和颜色选择器，但在使用时可能会混淆。没有可用的文档来描述这些工具的使用，要全靠你自己。
|
||||
|
||||
它的体验很流畅，我觉得这个工具很有潜力取代 Shutter 作为图像编辑工具（是的，我[用 Shutter 编辑截图][6]）。
|
||||
|
||||
我觉得最麻烦的是，添加元素后无法编辑/修改。你有撤消和重做选项，但如果你想修改一个你在 12 步前添加的文本，你就必须重做所有的步骤。这一点开发者可能会在未来的版本中进行研究。
|
||||
|
||||
### 在 Linux 上安装 Drawing
|
||||
|
||||
这是一款 Linux 专属应用。它也适用于基于 Linux 的智能手机，如 [PinePhone][7]。
|
||||
|
||||
有多种方式可以安装 Drawing。它在许多主要的 Linux 发行版的仓库中都有。
|
||||
|
||||
#### 基于 Ubuntu 的发行版
|
||||
|
||||
Drawing 包含在 Ubuntu 的 universe 仓库中，这意味着你可以从 Ubuntu 软件中心安装它。
|
||||
|
||||
但是，如果你想要最新的版本，有一个 [PPA][8] 可以轻松地在 Ubuntu、Linux Mint 和其他基于 Ubuntu 的发行版上安装 Drawing。
|
||||
|
||||
使用下面的命令：
|
||||
|
||||
```
|
||||
sudo add-apt-repository ppa:cartes/drawing
|
||||
sudo apt update
|
||||
sudo apt install drawing
|
||||
```
|
||||
|
||||
如果你想删除它，你可以使用以下命令：
|
||||
|
||||
```
|
||||
sudo apt remove drawing
|
||||
sudo add-apt-repository -r ppa:cartes/drawing
|
||||
```
|
||||
|
||||
#### 其他 Linux 发行版
|
||||
|
||||
检查你的发行版的包管理器中是否有 Drawing，然后在那里安装。如果你想要最新的版本，你可以使用 Flatpak 版本的应用。
|
||||
|
||||
[Drawing Flatpak][9]
|
||||
|
||||
**总结**
|
||||
|
||||
你还在用画图应用么？你用的是哪一款？如果你已经尝试过 Drawing，你的体验如何？
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: https://itsfoss.com/drawing-app/
|
||||
|
||||
作者：[Abhishek Prakash][a]
|
||||
选题：[lujun9972][b]
|
||||
译者：[geekpi](https://github.com/geekpi)
|
||||
校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创编译，[Linux中国](https://linux.cn/) 荣誉推出
|
||||
|
||||
[a]: https://itsfoss.com/author/abhishek/
|
||||
[b]: https://github.com/lujun9972
|
||||
[1]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2020/09/drawing-app-interface.jpg?resize=789%2C449&ssl=1
|
||||
[2]: https://itsfoss.com/open-source-paint-apps/
|
||||
[3]: https://maoschanz.github.io/drawing/
|
||||
[4]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2020/09/drawing-screenshot.jpg?resize=800%2C489&ssl=1
|
||||
[5]: https://i0.wp.com/itsfoss.com/wp-content/uploads/2020/09/using-drawing-app-linux.png?resize=787%2C473&ssl=1
|
||||
[6]: https://itsfoss.com/install-shutter-ubuntu/
|
||||
[7]: https://itsfoss.com/pinephone/
|
||||
[8]: https://launchpad.net/~cartes/+archive/ubuntu/drawing
|
||||
[9]: https://flathub.org/apps/details/com.github.maoschanz.drawing
|
||||
Loading…
Reference in New Issue
Block a user