Docker Compose

services:    # 必填,定义各个容器服务
  web:
    image: nginx

networks:    # 可选,定义自定义网络
  frontend:

volumes:     # 可选,定义命名数据卷
  db-data:

healthcheck:
  test: ["CMD", "curl", "-f", "http://localhost/health"]
  interval: 10s     # 每 10 秒检查一次
  timeout: 3s       # 单次检查超时时间
  retries: 3        # 连续失败 3 次判定为不健康
  start_period: 30s # 启动后宽限期

services:
  # Web 应用,由本地 Dockerfile 构建
  web:
    build: .
    ports:
      - "8080:8080"
    environment:
      - REDIS_HOST=redis
      - DB_HOST=mysql
      - DB_PASSWORD=${DB_PASSWORD}
    depends_on:
      redis:
        condition: service_started        # 等 Redis 启动
      mysql:
        condition: service_healthy        # 等 MySQL 健康检查通过
    restart: always

  # 缓存服务
  redis:
    image: redis:7-alpine
    volumes:
      - redis-data:/data
    restart: always

  # 数据库服务
  mysql:
    image: mysql:8
    environment:
      - MYSQL_ROOT_PASSWORD=${DB_PASSWORD}
      - MYSQL_DATABASE=appdb
    volumes:
      - mysql-data:/var/lib/mysql
    healthcheck:
      test: ["CMD", "mysqladmin", "ping", "-h", "localhost"]
      interval: 10s
      timeout: 5s
      retries: 5
      start_period: 30s
    restart: always

volumes:
  redis-data:
  mysql-data:

# .env 文件内容
DB_PASSWORD=s3cret-passw0rd

services:
  web:
    build: .
    volumes:
      - ./src:/app/src    # 本地代码覆盖容器内目录
    ports:
      - "8080:8080"

docker compose build        # 重新构建镜像
docker compose up -d        # 用新镜像重建容器
# 等效于一步:docker compose up -d --build