Docker实践8：Compose，docker实践compose

Docker实践8：Compose，docker实践compose

今天要在我的本子上搭建一个mediawiki环境，之前的经验，用fig去配置是最简单的了。可是下载fig失败，去官网一看才知道，fig已经被compose工具取代了。原文是这样说的：

Fig has been replaced by Docker Compose, and is now deprecated. The new documentation is on the Docker website.

既然如此，就去官网看看compose到底为何物。
compose是用来在docker中定义和运行复杂应用的小工具，比如在一个文件中定义多个容器，只用一行命令就可以让一切就绪并运行。它的功能与我们所熟知的fig相似，换句话说，compose是fig的替代产品，fig就这样退出docker的历史舞台了。

然而在github上的compose有这样的说法：

Fig has been renamed to Docker Compose, or just Compose for short. This has several implications for you:

The command you type is now docker-compose, not fig.
You should rename your fig.yml to docker-compose.yml.

看来fig是被重命名成compose了，配置文件变成了docker-compose.yml，其他都几乎一样。不但fig不能下载了，原来有fig工具的环境用fig去搭建mediawiki都不可用了，报错如下：

fig up -d
Creating hgserver_mediawiki_1...
Pulling image amclain/hgweb...
Traceback (most recent call last):
  File "<string>", line 3, in <module>
  File "/code/build/fig/out00-PYZ.pyz/fig.cli.main", line 31, in main
  File "/code/build/fig/out00-PYZ.pyz/fig.cli.docopt_command", line 21, in sys_dispatch
  File "/code/build/fig/out00-PYZ.pyz/fig.cli.command", line 28, in dispatch
  File "/code/build/fig/out00-PYZ.pyz/fig.cli.docopt_command", line 24, in dispatch
...
fig.progress_stream.StreamOutputError: Get https://index.docker.io/v1/repositories/amclain/hgweb/images: dial tcp: lookup index.docker.io on 10.202.72.118:53: read udp 10.202.72.118:53: i/o timeout

如此看来，使用compose是必须的了。
下面说说compose的用法。
1.安装compose
OS X和64位的Linux用如下命令安装。

# curl -L https://github.com/docker/compose/releases/download/1.1.0/docker-compose-`uname -s`-`uname -m` > /usr/local/bin/docker-compose

#chmod +x /usr/local/bin/docker-compose

其他平台可以像python包一样安装：

$ sudo pip install -U docker-compose

2.命令简介

$ docker-compose 
Fast, isolated development environments using Docker.

Usage:
  docker-compose [options] [COMMAND] [ARGS...]
  docker-compose -h|--help

Options:
  --verbose                 Show more output
  --version                 Print version and exit
  -f, --file FILE           Specify an alternate compose file (default: docker-compose.yml)
  -p, --project-name NAME   Specify an alternate project name (default: directory name)

Commands:
  build     Build or rebuild services
  help      Get help on a command
  kill      Kill containers
  logs      View output from containers
  port      Print the public port for a port binding
  ps        List containers
  pull      Pulls service images
  rm        Remove stopped containers
  run       Run a one-off command
  scale     Set number of containers for a service
  start     Start services
  stop      Stop services
  restart   Restart services
  up        Create and start containers

3.compose编写mediawiki的docker-compose.yml
首先编写compose的配置文件，语法与fig类似，文件名为docker-compose.yml，内容如下：

wiki2:
    image: 'nickstenning/mediawiki'
    ports:
        - "8880:80"
    links:
        - db:database
    volumes:
        - /data/wiki2:/data

db:
    image: "mysql"
    expose:
        - "3306"
    environment:
        - MYSQL_ROOT_PASSWORD=defaultpass

4.创建并启动mediawiki

$ docker-compose up -d