Docker从入门到精通之DockerCompose

　　Compose是一个用于定义和运行多容器Docker应用程序的工具。使用Compose，您可以使用YAML文件来配置应用程序的服务。然后，只需一个命令，就可以从配置中创建并启动所有服务。 Install Docker Compose下载docker compose $  sudo curl -L ＂https://github.com/docker/compose/releases/download/1.29.2/docker-compose-$(uname -s)-$(uname -m)＂ -o /usr/local/bin/docker-compose给docker compose设置可执行权限 $ sudo chmod +x /usr/local/bin/docker-compose验证 $ docker-compose --versionUninstallation$ sudo rm /usr/local/bin/docker-composeGetting Started
　　用python构建一个简易网页统计网页点击量，docker-compose进行发布
　　Step1：创建项目 创建项目目录 $ mkdir   test_web
　　$ cd   test_web 在项目目录中创建app.py文件，并把下面代码复制进去import    time
　　import    redis
　　from    flask    import    Flask
　　app   =  Flask  ( __name__  )
　　cache   =  redis  . Redis  ( host  = ＂redis＂  ,  port  = 6379  )
　　def    get_hit_count  ():
　　retries   =  5
　　while    True  :
　　try  :
　　return    cache  . incr  ( ＂hits＂  )
　　except    redis  . exceptions  . ConnectionError    as    exc  :
　　if    retries   ==  0  :
　　raise    exc
　　retries   -=  1
　　time  . sleep  ( 0.5  )
　　@app  . route  ( ＂/＂  )
　　def    hello  ():
　　count   =  get_hit_count  ()
　　return    ＂Hello World! I have been seen {} times. ＂  . format  ( count  ) 创建requirements.txt文件，以下内容复制进去flask redis
　　Step2：创建Dockerfile文件 FROM python:3.7-alpine WORKDIR /code ENV FLASK_APP=app.py ENV FLASK_RUN_HOST=0.0.0.0 RUN apk add --no-cache gcc musl-dev linux-headers COPY requirements.txt requirements.txt RUN pip install -r requirements.txt EXPOSE 5000 COPY . . CMD [＂flask＂, ＂run＂]
　　Step3：在docker-compose.yml中定义services version: ＂3.9＂ services:   web:     build: .     ports:       - ＂5000:5000＂   redis:     image: ＂redis:alpine＂
　　Step4：用Docker compose构建和运行app 进入项目目录，运行docker-compose up $ docker  -compose   up 在浏览器访问http://localhost:5000/ ，刷新页面看变化查看使用compose构建的镜像$ docker   images
　　Step5：绑定一个数据卷 version: ＂3.9＂ services:   web:     build: .     ports:       - ＂5000:5000＂     volumes:       - .:/code     environment:       FLASK_ENV: development   redis:     image: ＂redis:alpine＂
　　将当前目录与容器的/code目录绑定，这样可以动态修改代码
　　Step6：重新构建和运行app
　　先docker-compose down停止服务，在构建 $ docker-compose down $ docker-compose upCompose file
　　用YAML文件定义服务，默认文件是docker-compose.yml，包含4个顶级key，version、services、networks、volumes
　　参考compose-spec/spec.md at master · compose-spec/compose-spec · GitHub version
　　指定本 yml 依从的 compose版本 services
　　定义多个应用服务，包含环境配置、镜像构建等 build
　　指定构建镜像的路径 version: ＂3.9＂ services:   webapp:     build: ./appblkio_config
　　定义服务的block IO配置，参考compose-spec/spec.md at master · compose-spec/compose-spec · GitHub container_name
　　指定自定义容器名称 depends_on
　　定义服务间启动或关闭的依赖关系 services:   web:     build: .     depends_on:       - db       - redis   redis:     image: redis   db:     image: postgrescommand
　　覆盖容器启动的默认命令 command: [ ＂bundle＂, ＂exec＂, ＂thin＂, ＂-p＂, ＂3000＂ ]domainname
　　domainname   declares a custom domain name to use for the service container. entrypoint
　　覆盖容器默认的entrypoint env_file
　　从文件中添加环境变量到容器，可以是一个或多个文件 env_file: .envenv_file:   - ./a.env   - ./b.env
　　文件格式： # Set Rails/Rack environment RACK_ENV=development VAR=＂quoted＂environment
　　添加环境变量 environment:   RACK_ENV: development   SHOW: ＂true＂   USER_INPUT:expose
　　暴露端口，但不映射到宿主机，只被连接的服务访问，仅可以指定内部端口 expose:   - ＂3000＂   - ＂8000＂healthcheck
　　用于检测 docker 服务是否健康运行。 healthcheck:   test: [＂CMD＂, ＂curl＂, ＂-f＂, ＂http://localhost＂] # 设置检测程序   interval: 1m30s  # 设置检测间隔   timeout: 10s # 设置检测超时时间   retries: 3 # 设置重试次数   start_period: 40s # 启动后，多少秒开始启动检测程序image
　　指定容器运行的镜像 image: redis:5labels
　　设置容器标签 labels:   com.example.description: ＂Accounting webapp＂   com.example.department: ＂Finance＂labels:   - ＂com.example.description=Accounting webapp＂   - ＂com.example.department=Finance＂links
　　连接到另一个容器的网络，简单将就是让容器相互连通 web:   links:     - db     - db:database     - redislogging
　　服务的日志记录配置，driver：指定服务容器的日志记录驱动程序，默认值为json-file。有以下三个选项 driver: ＂json-file＂ driver: ＂syslog＂ driver: ＂none＂
　　仅在 json-file 驱动程序下，可以使用以下参数，限制日志得数量和大小。 logging:   driver: json-file   options:     max-size: ＂200k＂ # 单个文件大小为200k     max-file: ＂10＂ # 最多10个文件
　　syslog 驱动程序下，可以使用 syslog-address 指定日志接收地址。 logging:   driver: syslog   options:     syslog-address: ＂tcp://192.168.0.42:123＂network_mode
　　设置网络模式，格式如下： network_mode: ＂bridge＂ #桥接模式 network_mode: ＂host＂ network_mode: ＂none＂ network_mode: ＂service:[service name]＂networks
　　配置容器连接的网络 services:   some-service:     networks:       - some-network       - other-network networks:   some-network:     # Use a custom driver     driver: custom-driver-1   other-network:     # Use a custom driver which takes special options     driver: custom-driver-2services:   frontend:     image: awesome/webapp     networks:       - front-tier       - back-tier    monitoring:     image: awesome/monitoring     networks:       - admin    backend:     image: awesome/backend     networks:       back-tier:         aliases:           - database       admin:         aliases:           - mysql  networks:   front-tier:   back-tier:   admin:ipv4_address, ipv6_address
　　指定ip地址 services:   frontend:     image: awesome/webapp     networks:       front-tier:         ipv4_address: 172.16.238.10         ipv6_address: 2001:3984:3989::10  networks:   front-tier:     ipam:       driver: default       config:         - subnet: ＂172.16.238.0/24＂         - subnet: ＂2001:3984:3989::/64＂ports
　　端口映射，映射主机与容器端口，格式：Host:ontainer ports:      - ＂5000:5000＂restart
　　容器重启策略 restart: ＂no＂ restart: always restart: on-failure restart: unless-stoppedsecrets
　　存储敏感数据，比如密码 services:   frontend:     image: awesome/webapp     secrets:       - server-certificate secrets:   server-certificate:     file: ./server.certvolumes
　　将主机数据卷挂载到容器 services:   db:     image: postgres:latest     volumes:       - ＂/localhost/postgres.sock:/var/run/postgres/postgres.sock＂       - ＂/localhost/data:/var/lib/postgresql/data＂working_dir
　　覆盖容器工作目录 Volumes 顶级目录services:   backend:     image: awesome/database     volumes:       - db-data:/etc/data    backup:     image: backup-service     volumes:       - db-data:/var/lib/backup/data  volumes:   db-data:Networks 顶级目录services:   frontend:     image: awesome/webapp     networks:       - front-tier       - back-tier  networks:   front-tier:   back-tier:     driver: bridgedocker-compose 命令$ docker-compose --help Define and run multi-container applications with Docker.  Usage:   docker-compose [-f ...] [--profile ...] [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)   --profile NAME              Specify a profile to enable   --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 informationSwarm集群