my docker-compose file

version: "3.7"
networks:
  mynet:

services:

  app:
    image: node:12-alpine
    command: sh -c "yarn install && yarn run dev"
    ports:
      - 3000:3000
    working_dir: /app
    volumes:
      - ./:/app
    environment:
      MYSQL_HOST: peeter-mysql
      MYSQL_DB: todos
      MYSQL_USER: user
      MYSQL_PASSWORD: secret
    networks:
      - mynet

  peeter-mysql:
    image: mysql
    command: --default-authentication-plugin=mysql_native_password
    volumes:
      - todo-mysql-data:/var/lib/mysql
    environment:
      MYSQL_DATABASE: todos
      MYSQL_ROOT_PASSWORD: pass
      MYSQL_USER: user
      MYSQL_PASSWORD: secret
      MYSQL_TCP_PORT: 3306
    networks:
      - mynet

  phpmyadmin:
    image: phpmyadmin
    ports:
      - 8081:80
    links:
      - peeter-mysql
    environment:
      MYSQL_ROOT_PASSWORD: pass
      PMA_HOSTS: peeter-mysql
      MYSQL_USER: secret
      MYSQL_PASSWORD: secret
    # Wait for "mysql" container to start first
    depends_on:
      - peeter-mysql
    networks:
      - mynet

volumes:
  todo-mysql-data: