diff --git a/sources/tech/20160512 Rapid prototyping with docker-compose.md b/sources/tech/20160512 Rapid prototyping with docker-compose.md deleted file mode 100644 index 98b203f440..0000000000 --- a/sources/tech/20160512 Rapid prototyping with docker-compose.md +++ /dev/null @@ -1,144 +0,0 @@ - -Translating by Firstadream - -Rapid prototyping with docker-compose -======================================== - -In this write-up we'll look at a Node.js prototype for **finding stock of the Raspberry PI Zero** from three major outlets in the UK. - -I wrote the code and deployed it to an Ubuntu VM in Azure within a single evening of hacking. Docker and the docker-compose tool made the deployment and update process extremely quick. - -### Remember linking? - -If you've already been through the [Hands-On Docker tutorial][1] then you will have experience linking Docker containers on the command line. Linking a Node hit counter to a Redis server on the command line may look like this: - -``` -$ docker run -d -P --name redis1 -$ docker run -d hit_counter -p 3000:3000 --link redis1:redis -``` - -Now imagine your application has three tiers - -- Web front-end -- Batch tier for processing long running tasks -- Redis or mongo database - -Explicit linking through `--link` is just about manageable with a couple of containers, but can get out of hand as we add more tiers or containers to the application. - -### Enter docker-compose - -![](http://blog.alexellis.io/content/images/2016/05/docker-compose-logo-01.png) ->Docker Compose logo - -The docker-compose tool is part of the standard Docker Toolbox and can also be downloaded separately. It provides a rich set of features to configure all of an application's parts through a plain-text YAML file. - -The above example would look like this: - -``` -version: "2.0" -services: - redis1: - image: redis - hit_counter: - build: ./hit_counter - ports: - - 3000:3000 -``` - -From Docker 1.10 onwards we can take advantage of network overlays to help us scale out across multiple hosts. Prior to this linking only worked across a single host. The `docker-compose scale` command can be used to bring on more computing power as the need arises. - ->View the [docker-compose][2] reference on docker.com - -### Real-world example: Raspberry PI Stock Alert - -![](http://blog.alexellis.io/content/images/2016/05/Raspberry_Pi_Zero_ver_1-3_1_of_3_large.JPG) ->The new Raspberry PI Zero v1.3 image courtesy of Pimoroni - -There is a huge buzz around the Raspberry PI Zero - a tiny microcomputer with a 1GHz CPU and 512MB RAM capable of running full Linux, Docker, Node.js, Ruby and many other popular open-source tools. One of the best things about the PI Zero is that costs only 5 USD. That also means that stock gets snapped up really quickly. - -*If you want to try Docker or Swarm on the PI check out the tutorial below.* - ->[Docker Swarm on the PI Zero][3] - -### Original site: whereismypizero.com - -I found a webpage which used screen scraping to find whether 4-5 of the most popular outlets had stock. - -- The site contained a static HTML page -- Issued one XMLHttpRequest per outlet accessing /public/api/ -- The server issued the HTTP request to each shop and performed the scraping - -Every call to /public/api/ took 3 seconds to execute and using Apache Bench (ab) I was only able to get through 0.25 requests per second. - -### Reinventing the wheel - -The retailers didn't seem to mind whereismypizero.com scraping their sites for stock, so I set about writing a similar tool from the ground up. I had the intention of handing a much higher amount of requests per second through caching and de-coupling the scrape from the web tier. Redis was the perfect tool for the job. It allowed me to set an automatically expiring key/value pair (i.e. a simple cache) and also to transmit messages between Node processes through pub/sub. - ->Fork or star the code on Github: [alexellis/pi_zero_stock][4] - -If you've worked with Node.js before then you will know it is single-threaded and that any CPU intensive tasks such as parsing HTML or JSON could lead to a slow-down. One way to mitigate that is to use a second worker process and a Redis messaging channel as connective tissue between this and the web tier. - -- Web tier - -Gives 200 for cache hit (Redis key exists for store) - -Gives 202 for cache miss (Redis key doesn't exist, so issues message) - -Since we are only ever reading a Redis key the response time is very quick. -- Stock Fetcher - -Performs HTTP request - -Scrapes for different types of web stores - -Updates a Redis key with a cache expire of 60 seconds - -Also locks a Redis key to prevent too many in-flight HTTP requests to the web stores. -``` -version: "2.0" -services: - web: - build: ./web/ - ports: - - "3000:3000" - stock_fetch: - build: ./stock_fetch/ - redis: - image: redis -``` - -*The docker-compose.yml file from the example.* - -Once I had this working locally deploying to an Ubuntu 16.04 image in the cloud (Azure) took less than 5 minutes. I logged in, cloned the repository and typed in `docker compose up -d`. That was all it took - rapid prototyping a whole system doesn't get much better. Anyone (including the owner of whereismypizero.com) can deploy the new solution with just two lines: - -``` -$ git clone https://github.com/alexellis/pi_zero_stock -$ docker-compose up -d -``` - -Updating the site is easy and just involves a `git pull` followed by a `docker-compose up -d` with the `--build` argument passed along. - -If you are still linking your Docker containers manually, try Docker Compose for yourself or my code below: - ->Fork or star the code on Github: [alexellis/pi_zero_stock][5] - -### Check out the test site - -The test site is currently deployed now using docker-compose. - ->[stockalert.alexellis.io][6] - -![](http://blog.alexellis.io/content/images/2016/05/Screen-Shot-2016-05-16-at-22-34-26-1.png) - -Preview as of 16th of May 2016 - ----------- -via: http://blog.alexellis.io/rapid-prototype-docker-compose/ - -作者：[Alex Ellis][a] -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) 原创翻译，[Linux中国](https://linux.cn/) 荣誉推出 - -[a]: http://blog.alexellis.io/author/alex/ -[1]: http://blog.alexellis.io/handsondocker -[2]: https://docs.docker.com/compose/compose-file/ -[3]: http://blog.alexellis.io/dockerswarm-pizero/ -[4]: https://github.com/alexellis/pi_zero_stock -[5]: https://github.com/alexellis/pi_zero_stock -[6]: http://stockalert.alexellis.io/ - diff --git a/translated/tech/20160512 Rapid prototyping with docker-compose.md b/translated/tech/20160512 Rapid prototyping with docker-compose.md new file mode 100644 index 0000000000..ece6a129e0 --- /dev/null +++ b/translated/tech/20160512 Rapid prototyping with docker-compose.md @@ -0,0 +1,142 @@ + +通过docker-compose进行快速原型设计 +======================================== +在这篇文章中，我们将考察一个Node.js原型，该原型用于从英国三个主要折扣网店查找“Raspberry PI Zero”的库存。 + +我写好了代码，然后经过一晚的hacking把它部署在Aure上的Ubuntu虚拟机上。Docker和docker-compose工具使得部署和更新过程非常快。 + +### 还记得链接指令吗？ + +如果你已经阅读过[Hands-on Docker tutorial][1]，那么你应该已经可以使用命令行链接Docker容器。通过命令行将节点命中计数器链接到Redis服务器，其命令可能如下所示： + +``` +$ docker run -d -P --name redis1 +$ docker run -d hit_counter -p 3000:3000 --link redis1:redis +``` + +现在假设你的应用程序分为三层： + +- Web前端 +- 处理长时间运行任务的批处理层 +- Redis或者mongo数据库 + +通过`--link`的显式链接只是可以用几个容器来管理，但是可能会因为我们向应用程序添加更多层或容器而失控。 + +###加入docker-compose + +![](http://blog.alexellis.io/content/images/2016/05/docker-compose-logo-01.png) +>Docker Compose logo + +docker-compose工具是标准Docker工具箱的一部分，也可以单独下载。 它提供了一组丰富的功能，通过纯文本YAML文件配置所有应用程序的部件。 + +上面的例子看起来像这样： + +``` +version: "2.0" +services: + redis1: + redis1: + image: redis + hit_counter: + build: ./hit_counter + ports: + - 3000:3000 +``` + +从Docker 1.10开始，我们可以利用网络覆盖来帮助我们在多个主机上进行扩展。 在此之前，链接仅在单个主机上工作。 “docker-compose scale”命令可以用来在需要时带来更多的计算能力。 + +>查看docker.com上的[docker-compose] [2]参考 + +真实工作示例：Raspberry PI股票警示 + +![](http://blog.alexellis.io/content/images/2016/05/Raspberry_Pi_Zero_ver_1-3_1_of_3_large.JPG) +>新的Raspberry PI Zero v1.3图片由Pimoroni提供 + +Raspberry PI Zero嗡嗡作响 - 它是一个极小的微型计算机，具有1GHz CPU和512MB RAM，可以运行完整的Linux、Docker、Node.js、Ruby和其他许多流行的开源工具。 PI Zero最好的优点之一就是它成本只有5美元。 这也意味着它去库存的速度非常之快。 + +*如果你想在PI上尝试Docker和Swarm，请查看下面的教程。* + +>[Docker Swarm on the PI Zero][3] + +### 原始网站：whereismypizero.com + +我发现一个网页，它使用屏幕抓取以找出4-5个最受欢迎的折扣网店是否有库存。 + +- 网站包含静态HTML网页 +- 向每个折扣网店发出一个XMLHttpRequest访问/ public / api / +- 服务器向每个网店发出HTTP请求并执行抓屏 + +每一次对/ public / api /的调用，其执行花3秒钟，而使用Apache Bench（ab），我每秒只能得到0.25个请求。 + +### 重新发明轮子 + +零售商似乎并不介意whereismypizero.com抓取他们的网站的商品库存信息，所以我开始从头写一个类似的工具。 我有意通过缓存和解耦从web层处理更多的抓取请求。 Redis是执行这项工作的完美工具。 它允许我设置一个自动过期的键/值对（即一个简单的缓存），还可以通过pub / sub在节点进程之间传输消息。 + +>复刻或者追踪github上的代码: [alexellis/pi_zero_stock][4] + +如果之前使用过Node.js，你肯定知道它是单线程的，并且任何CPU密集型任务，如解析HTML或JSON都可能导致速度放缓。 一种缓解这种情况的方法是使用一个工作进程和Redis消息通道作为它和web层之间的连接组织。 + +- Web层 + 使用200作为缓冲命中（存储Redis键） + 使用202作为高速缓存未命中（Redis键不存在，因此出现问题消息） + 因为我们只是读一个Redis键，响应时间非常快。 +- 库存抓取器 + 执行HTTP请求 + 用于在不同类型的网店上抓屏 + 更新具有高速缓存超时时间为60秒的Redis键 + 另外，锁定一个Redis键，以防止过多的HTTP请求到网店。 +``` +version: "2.0" +services: + web: + build: ./web/ + ports: + - "3000:3000" + stock_fetch: + build: ./stock_fetch/ + redis: + image: redis +``` + +*来自示例的docker-compose.yml文件* + +一旦本地正常工作，再向Azure的Ubuntu 16.04镜像云部署就轻车熟路，只花了不到5分钟。 我登录，克隆仓库并键入“docker compose up -d”， 这就是所有的工作 - 快速实现整个系统的原型不会比这几个步骤更多。 任何人（包括whereismypizero.com的所有者）只需两行命令就可以部署新解决方案： + +``` +$ git clone https://github.com/alexellis/pi_zero_stock +$ docker-compose up -d +``` + +更新网站很容易，只需要一个`git pull'`命令，然后执行`docker-compose up -d`命令，该命令需要带上`--build`参数。 + +如果你仍然手动链接你的Docker容器，请自己或使用如下我的代码尝试Docker Compose： + +>复刻或者追踪github上的代码： [alexellis/pi_zero_stock][5] + +###一睹测试网站芳容 + +目前测试网站使用docker-compose部署。 + +>[stockalert.alexellis.io][6] + +![](http://blog.alexellis.io/content/images/2016/05/Screen-Shot-2016-05-16-at-22-34-26-1.png) + +预览截止2016年5月16日 + +---------- +via: http://blog.alexellis.io/rapid-prototype-docker-compose/ + +作者：[Alex Ellis][a] +译者：[firstadream](https://github.com/firstadream) +校对：[校对者ID](https://github.com/校对者ID) + +本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创翻译，[Linux中国](https://linux.cn/) 荣誉推出 + +[a]: http://blog.alexellis.io/author/alex/ +[1]: http://blog.alexellis.io/handsondocker +[2]: https://docs.docker.com/compose/compose-file/ +[3]: http://blog.alexellis.io/dockerswarm-pizero/ +[4]: https://github.com/alexellis/pi_zero_stock +[5]: https://github.com/alexellis/pi_zero_stock +[6]: http://stockalert.alexellis.io/ +