services:
  mongo:
    image: mongo
    ports:
     - 3456:27017
    environment:
      MONGO_INITDB_ROOT_USERNAME: root
      MONGO_INITDB_ROOT_PASSWORD: example
      MONGO_INITDB_DATABASE: the_database

    volumes: 
      - ./mongo/mongo-init.js:/docker-entrypoint-initdb.d/mongo-init.js