Docker 哲学 - compose.yaml 指令

news2024/10/12 18:23:53

compose.yaml 的 image commond working_dir 和 dockerfile的 from cmd workdir 区别在哪里。为什么 dockerfile制定过了。compose还要再写一个。是处于个性化还是有不同的意义

如果 dockerfile 的 from 是 node:16 ，compose.yaml 的 images 是 node:18 那么直接 docker run 用的就是默认 16 的node 但是 compose up启动用的就是 18的node

depends_on：

总结：

depends_on 可以设置容器的启动顺序，如果一个服务依赖另一个服务，那么就可以自定义控制

所以来服务的状态来启动目标服务

有几种语法：

depends_on:
      - db
      - redis
short syntax

1、跟依赖服务的名字

Compose creates services in dependency order. In the following example, db and redis are created before web.

Compose removes services in dependency order. In the following example, web is removed before db and redis.

Compose guarantees dependency services have been started before starting a dependent service. Compose waits for dependency services to be "ready" before starting a dependent service.

弊端：不会等依赖服务完全初始化完成只是一个 ready

2、

depends_on:

可以有三个属性：

restart 设置为 true时依赖服务有更新，compose自动重启

condition: 自定义条件决定什么时候启动该服务有三个属性

required：是否与依赖服务之间存在上下文关系

condition 的三个属性

service_started ：不会等依赖服务完全初始化完成只是一个 ready 等同直接写服务名

service_healthy: 该属性的值由另一个容器的 service下字段 healthy_check 决定

service_completion_successfully:依赖服务完全初始化

介绍

healthy_check:

version: '3'

services:
  rabbitmq:
    hostname: rabbitmq_host
    container_name: 'mq'
    image: rabbitmq:3.9.11-management
    restart: always
    ports:
      - "5772:5672"  # AMQP
      - "15772:15672"  # Web UI
    networks:
      - app-network
    environment:
      RABBITMQ_DEFAULT_USER: root
      RABBITMQ_DEFAULT_PASS: pwd
      RABBITMQ_DEFAULT_VHOST: /
    volumes:
      - rabbitmq_data:/var/lib/rabbitmq/mnesia

    healthcheck:
      test: [ "CMD", "rabbitmq-diagnostics", "ping" ]
      interval: 50s
      timeout: 5s
      retries: 3


  selenium:
    container_name: 'selenium'
    image: selenium/standalone-chrome
    restart: always
    ports:
      - "4444:4444"

    networks:
      - app-network

    healthcheck:
      test: [ "CMD", "curl", "-f", "http://localhost:4444/wd/hub/status" ]
      interval: 30s
      timeout: 5s
      retries: 3


  db:
    container_name: 'mysql8'
    image: mysql:8.0.32
#    hostname: mysql_host
    user: root
    command:
      --default-authentication-plugin=mysql_native_password
      --character-set-server=utf8mb4
      --collation-server=utf8mb4_unicode_ci

    environment:
      LANG: C.UTF-8
      MYSQL_ROOT_PASSWORD: pwd
      MYSQL_DATABASE: yinlian

    ports:
      - "3306:3306"

    volumes:
      - "./data/db/data:/var/lib/mysql"
      - "./data/db/mysql-files:/var/lib/mysql-files"
      - "./build/docker/mysqldb/my.cnf:/etc/my.cnf"

    networks:
      - app-network

    healthcheck:
      test: [ "CMD", "mysqladmin", "ping", "-h", "localhost" ]
      interval: 30s
      timeout: 5s
      retries: 3

  app-producer:
    container_name: 'producer'
    build:
      context: .
      dockerfile: Dockerfile
    ports:
      - "8001:8001"

    command: ['echo','hello world, Frank']
    depends_on:
      db:
        condition: service_healthy

      rabbitmq:
        condition: service_healthy

      selenium:
        condition: service_healthy

    networks:
      - app-network


networks:
  app-network:
    driver: bridge

volumes:
  rabbitmq_data:
    driver: local