Implement command permission checking and relevant exceptions

backend/mirai-console/src/main/kotlin/net/mamoe/mirai/console/command/CommandExecuteResult.kt

@@ -1,3 +1,12 @@
+/*
+ * Copyright 2020 Mamoe Technologies and contributors.
+ *
+ * 此源代码的使用受 GNU AFFERO GENERAL PUBLIC LICENSE version 3 许可证的约束, 可以在以下链接找到该许可证.
+ * Use of this source code is governed by the GNU AGPLv3 license that can be found through the following link.
+ *
+ * https://github.com/mamoe/mirai/blob/master/LICENSE
+ */
+
 @file:Suppress("unused")
 
 package net.mamoe.mirai.console.command
@@ -78,6 +87,23 @@ sealed class CommandExecuteResult {
         override val status: CommandExecuteStatus get() = CommandExecuteStatus.COMMAND_NOT_FOUND
     }
 
+    /** 权限不足 */
+    class PermissionDenied(
+        /** 尝试执行的指令 */
+        override val command: Command,
+        /** 尝试执行的指令名 */
+        override val commandName: String
+    ) : CommandExecuteResult() {
+        /** 基础分割后的实际参数列表, 元素类型可能为 [Message] 或 [String] */
+        override val args: Nothing? get() = null
+
+        /** 指令执行时发生的错误, 总是 `null` */
+        override val exception: Nothing? get() = null
+
+        /** 指令最终执行状态, 总是 [CommandExecuteStatus.PERMISSION_DENIED] */
+        override val status: CommandExecuteStatus get() = CommandExecuteStatus.PERMISSION_DENIED
+    }
+
     /**
      * 指令的执行状态
      */
@@ -89,7 +115,10 @@ sealed class CommandExecuteResult {
         EXECUTION_EXCEPTION,
 
         /** 没有匹配的指令 */
-        COMMAND_NOT_FOUND
+        COMMAND_NOT_FOUND,
+
+        /** 权限不足 */
+        PERMISSION_DENIED
     }
 }
 
@@ -121,6 +150,18 @@ fun CommandExecuteResult.isExecutionException(): Boolean {
     return this is CommandExecuteResult.ExecutionException
 }
 
+/**
+ * 当 [this] 为 [CommandExecuteResult.ExecutionException] 时返回 `true`
+ */
+@JvmSynthetic
+fun CommandExecuteResult.isPermissionDenied(): Boolean {
+    contract {
+        returns(true) implies (this@isPermissionDenied is CommandExecuteResult.PermissionDenied)
+        returns(false) implies (this@isPermissionDenied !is CommandExecuteResult.PermissionDenied)
+    }
+    return this is CommandExecuteResult.PermissionDenied
+}
+
 /**
  * 当 [this] 为 [CommandExecuteResult.ExecutionException] 时返回 `true`
  */

backend/mirai-console/src/main/kotlin/net/mamoe/mirai/console/command/CommandExecutionException.kt

@@ -0,0 +1,34 @@
+/*
+ * Copyright 2020 Mamoe Technologies and contributors.
+ *
+ * 此源代码的使用受 GNU AFFERO GENERAL PUBLIC LICENSE version 3 许可证的约束, 可以在以下链接找到该许可证.
+ * Use of this source code is governed by the GNU AGPLv3 license that can be found through the following link.
+ *
+ * https://github.com/mamoe/mirai/blob/master/LICENSE
+ */
+
+@file:Suppress("MemberVisibilityCanBePrivate")
+
+package net.mamoe.mirai.console.command
+
+/**
+ * 在 [executeCommand] 中, [Command.onCommand] 抛出异常时包装的异常.
+ */
+class CommandExecutionException(
+    /**
+     * 执行过程发生异常的指令
+     */
+    val command: Command,
+    /**
+     * 匹配到的指令名
+     */
+    val name: String,
+    cause: Throwable
+) : RuntimeException(
+    "Exception while executing command '${command.primaryName}'",
+    cause
+) {
+    override fun toString(): String =
+        "CommandExecutionException(command=$command, name='$name')"
+}
+

backend/mirai-console/src/main/kotlin/net/mamoe/mirai/console/command/CommandManager.kt

@@ -131,7 +131,7 @@ fun Command.unregister(): Boolean = InternalCommandManager.modifyLock.withLock {
 //// executing without detailed result (faster)
 
 /**
- * 解析并执行一个指令
+ * 解析并执行一个指令. 将会检查指令权限, 在无权限时抛出
  *
  * @param messages 接受 [String] 或 [Message], 其他对象将会被 [Any.toString]
  *
@@ -160,32 +160,6 @@ suspend fun CommandSender.executeCommand(message: MessageChain): Command? {
 }
 
 
-/**
- * 在 [executeCommand] 中, [Command.onCommand] 抛出异常时包装的异常.
- */
-class CommandExecutionException(
-    /**
-     * 执行过程发生异常的指令
-     */
-    val command: Command,
-    /**
-     * 匹配到的指令名
-     */
-    val name: String,
-    /**
-     * 基础分割后的实际参数列表, 元素类型可能为 [Message] 或 [String]
-     */
-    val args: Array<out Any>,
-    cause: Throwable
-) : RuntimeException(
-    "Exception while executing command '${command.primaryName}' with args ${args.joinToString { "'$it'" }}",
-    cause
-) {
-    override fun toString(): String =
-        "CommandExecutionException(command=$command, name='$name', args=${args.contentToString()})"
-}
-
-
 //// execution with detailed result
 
 /**
@@ -224,6 +198,10 @@ internal suspend inline fun CommandSender.executeCommandDetailedInternal(
     val command =
         InternalCommandManager.matchCommand(commandName) ?: return CommandExecuteResult.CommandNotFound(commandName)
     val args = messages.flattenCommandComponents().dropToTypedArray(1)
+
+    if (!command.testPermission(this)) {
+        return CommandExecuteResult.PermissionDenied(command, commandName)
+    }
     kotlin.runCatching {
         command.onCommand(this, args)
     }.fold(

backend/mirai-console/src/main/kotlin/net/mamoe/mirai/console/command/CommandPermission.kt

@@ -25,6 +25,9 @@ import net.mamoe.mirai.contact.isOwner
 interface CommandPermission {
     /**
      * 判断 [this] 是否拥有这个指令的权限
+     *
+     * @see CommandSender.hasPermission
+     * @see CommandPermission.testPermission
      */
     fun CommandSender.hasPermission(): Boolean
 
@@ -32,11 +35,13 @@ interface CommandPermission {
     /**
      * 满足两个权限其中一个即可使用指令
      */ // no extension for Java
+    @JvmDefault
     infix fun or(another: CommandPermission): CommandPermission = OrCommandPermission(this, another)
 
     /**
      * 同时拥有两个权限才能使用指令
      */ // no extension for Java
+    @JvmDefault
     infix fun and(another: CommandPermission): CommandPermission = AndCommandPermission(this, another)
 
 
@@ -48,7 +53,7 @@ interface CommandPermission {
     }
 
     /**
-     * 任何人都不能使用这个指令. 指令只能通过代码在 [execute] 使用
+     * 任何人都不能使用这个指令. 指令只能通过调用 [Command.onCommand] 执行.
      */
     object None : CommandPermission {
         override fun CommandSender.hasPermission(): Boolean = false
@@ -94,7 +99,7 @@ interface CommandPermission {
      * 仅控制台能使用和这个指令
      */
     object Console : CommandPermission {
-        override fun CommandSender.hasPermission(): Boolean = false
+        override fun CommandSender.hasPermission(): Boolean = this is ConsoleCommandSender
     }
 
     object Default : CommandPermission by (Manager or Console)
@@ -117,6 +122,8 @@ inline fun CommandSender.hasPermission(permission: CommandPermission): Boolean =
 
 inline fun CommandPermission.testPermission(sender: CommandSender): Boolean = this.run { sender.hasPermission() }
 
+inline fun Command.testPermission(sender: CommandSender): Boolean = sender.hasPermission(this.permission)
+
 internal class OrCommandPermission(
     private val first: CommandPermission,
     private val second: CommandPermission

backend/mirai-console/src/main/kotlin/net/mamoe/mirai/console/command/CommandPermissionDeniedException.kt

@@ -0,0 +1,25 @@
+/*
+ * Copyright 2020 Mamoe Technologies and contributors.
+ *
+ * 此源代码的使用受 GNU AFFERO GENERAL PUBLIC LICENSE version 3 许可证的约束, 可以在以下链接找到该许可证.
+ * Use of this source code is governed by the GNU AGPLv3 license that can be found through the following link.
+ *
+ * https://github.com/mamoe/mirai/blob/master/LICENSE
+ */
+
+package net.mamoe.mirai.console.command
+
+/**
+ * 在 [executeCommand] 中, [CommandSender] 未拥有 [Command.permission] 所要求的权限时抛出的异常.
+ *
+ * 总是作为 [CommandExecutionException.cause].
+ */
+class CommandPermissionDeniedException(
+    /**
+     * 执行过程发生异常的指令
+     */
+    val command: Command
+) : RuntimeException("Permission denied while executing command '${command.primaryName}'") {
+    override fun toString(): String =
+        "CommandPermissionDeniedException(command=$command)"
+}

backend/mirai-console/src/main/kotlin/net/mamoe/mirai/console/command/internal.kt

@@ -171,18 +171,19 @@ internal suspend inline fun CommandSender.executeCommandInternal(
     commandName: String
 ): Command? {
     val command = InternalCommandManager.matchCommand(commandName) ?: return null
-    val rawInput = messages.flattenCommandComponents()
 
-    val loweredArgs = rawInput.dropToTypedArray(1)
+    if (!command.testPermission(this)) {
+        throw CommandExecutionException(command, commandName, CommandPermissionDeniedException(command))
+    }
 
     kotlin.runCatching {
-        command.onCommand(this, loweredArgs)
+        command.onCommand(this, messages.flattenCommandComponents().dropToTypedArray(1))
     }.fold(
         onSuccess = {
             return command
         },
         onFailure = {
-            throw CommandExecutionException(command, commandName, loweredArgs, it)
+            throw CommandExecutionException(command, commandName, it)
         }
     )
 }