Docker Compose 多容器部署

需求描述

很多时候我们需要多个容器配合使用，但是一个一个的去配置部署是一件很麻烦的事情，这时候就需要一个能够一处配置，到处使用的方案，于是就有了compose。

Compose 安装

安装比较简单，查一下文档就知道了，比如这里要安装1.21.2版本：

sudo curl -L https://github.com/docker/compose/releases/download/1.21.2/docker-compose-$(uname -s)-$(uname -m) -o /usr/local/bin/docker-compose     # 下载可执行文件

sudo chmod +x /usr/local/bin/docker-compose   # 如果需要的话，添加可执行权限

docker-compose --version  # 试一试安装成功了没有

一个例子

compose默认使用名为docker-compose.yml的配置文件，我们先来试一试。

下面的例子创建了一组container，主体部分是一个wordpress服务，使用mysql作为数据库。

docker-compose.yml

version: '3'

services:

  wordpress:
    image: wordpress
    ports:
      - 8080:80
    depends_on:
      - mysql
    environment:
      WORDPRESS_DB_HOST: mysql:3306
      WORDPRESS_DB_PASSWORD: root
    networks:
      - my-bridge

  mysql:
    image: mysql:5.7
    environment:
      MYSQL_ROOT_PASSWORD: root
      MYSQL_DATABASE: wordpress
    volumes:
      - mysql-data:/var/lib/mysql
    networks:
      - my-bridge

volumes:
  mysql-data:

networks:
  my-bridge:
    driver: bridge

然后在命令行执行

docker-compose up

程序便会在当前目录下找到docker-compose.yml文件并根据配置创建相应的container。

如果要指定yml文件， 可执行

docker-compose -f youfile.yml up

这样的话，运行的日志会持续打印，如果要让其后台运行的话，和docker一样，加入-d参数就可以了。

然后执行一下docker ps，看看container是否正常启动。

最后打开浏览器，看一看是否能打开wordpress。

更多命令

compose 还有许多功能，我们可以使用docker-compose --help查看

docker-compose --help

Define and run multi-container applications with Docker.

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

Options:
  -f, --file FILE             Specify an alternate compose file
                              (default: docker-compose.yml)
  -p, --project-name NAME     Specify an alternate project name
                              (default: directory name)
  --verbose                   Show more output
  --log-level LEVEL           Set log level (DEBUG, INFO, WARNING, ERROR, CRITICAL)
  --no-ansi                   Do not print ANSI control characters
  -v, --version               Print version and exit
  -H, --host HOST             Daemon socket to connect to

  --tls                       Use TLS; implied by --tlsverify
  --tlscacert CA_PATH         Trust certs signed only by this CA
  --tlscert CLIENT_CERT_PATH  Path to TLS certificate file
  --tlskey TLS_KEY_PATH       Path to TLS key file
  --tlsverify                 Use TLS and verify the remote
  --skip-hostname-check       Don't check the daemon's hostname against the
                              name specified in the client certificate
  --project-directory PATH    Specify an alternate working directory
                              (default: the path of the Compose file)
  --compatibility             If set, Compose will attempt to convert deploy
                              keys in v3 files to their non-Swarm equivalent

Commands:
  build              Build or rebuild services
  bundle             Generate a Docker bundle from the Compose file
  config             Validate and view the Compose file
  create             Create services
  down               Stop and remove containers, networks, images, and volumes
  events             Receive real time events from containers
  exec               Execute a command in a running container
  help               Get help on a command
  images             List images
  kill               Kill containers
  logs               View output from containers
  pause              Pause services
  port               Print the public port for a port binding
  ps                 List containers
  pull               Pull service images
  push               Push service images
  restart            Restart services
  rm                 Remove stopped containers
  run                Run a one-off command
  scale              Set number of containers for a service
  start              Start services
  stop               Stop services
  top                Display the running processes
  unpause            Unpause services
  up                 Create and start containers
  version            Show the Docker-Compose version information

其中很多命令和docker的差不多，比较容易理解。

再来一个例子

如果我们需要自己创建一个image来启动container 怎么弄的

Dockerfile

FROM python:2.7
LABEL maintaner="Peng Xiao [email protected]"
COPY . /app
WORKDIR /app
RUN pip install flask redis
EXPOSE 5000
CMD [ "python", "app.py" ]

docker-compose.yml

version: "3"

services:

  redis:
    image: redis

  web:
    build:
      context: .
      dockerfile: Dockerfile
    ports:
      - 8080:5000
    environment:
      REDIS_HOST: redis

然后创建的方式和上面一样。