Painless Docker - 2nd Edition

cat < docker-compose.yml
version: '3.9'

services:
  db:
    image: mysql:9.6.0
    volumes:
      - db_data:/var/lib/mysql
    environment:
      MYSQL_ROOT_PASSWORD_FILE: /run/secrets/db_root_password
      MYSQL_DATABASE: wordpress
      MYSQL_USER: wordpress
      MYSQL_PASSWORD_FILE: /run/secrets/db_password
    secrets:
      - db_root_password
      - db_password
    networks:
      - wordpress-network
    deploy:
      placement:
        constraints:
          - node.role==manager
      resources:
        limits:
          cpus: '1'
          memory: 800M
        reservations:
          cpus: '0.5'
          memory: 500M
      update_config:
        parallelism: 1
        delay: 10s
        order: start-first
      restart_policy:
        condition: any
        delay: 5s
        max_attempts: 3
        window: 120s

  wordpress:
    depends_on:
      - db
    image: wordpress:6.9.1-apache
    ports:
      - "8000:80"
    environment:
      WORDPRESS_DB_HOST: db:3306
      WORDPRESS_DB_USER: wordpress
      WORDPRESS_DB_PASSWORD_FILE: /run/secrets/db_password
    secrets:
      - db_password
    networks:
      - wordpress-network
    healthcheck:
      test: ["CMD", "curl", "-f", "http://localhost:80"]
      interval: 1m30s
      timeout: 10s
      retries: 3
    deploy:
      placement:
        constraints: