version: '3'
services:

  db:
    image: mysql:5.7
    volumes:
      - db_data:/var/lib/mysql
    restart: always
    environment:
      MYSQL_ROOT_PASSWORD: root
      MYSQL_DATABASE: test
      MYSQL_USER: test
      MYSQL_PASSWORD: testpassword

  app1:
    build: ./simple-node-app
    environment:
      DB_HOST: db
      DB_DATABASE: test
      DB_USER: teste
      DB_PASSWORD: testpassword

  app2:
    extends:
      file: ./app2.yml
      service: app2

  app3:
    extends:
      service: app1

  app4:
    extends:
      file: ./simple-node-app-1235/app4.yml
      service: app4
  
volumes:
  db_data: {}