mongo.yml

version: '3.5'
services:
  mongo:
    image: mongo
    expose:
      - 27017
    volumes:
      - ./mongo_data:/data/db
    ports:
      - "127.0.0.1:27017:27017"
    networks:
      - mongo

networks:
  mongo:
    name: mongo

myapp.yml

version: '3.5'
services:
  app:
    container_name: app
    restart: always
    build: .
    ports:
      - '3001:3000'
    networks:
      - mongo

networks:
  mongo:
    external: true

sharelatex.yml

version: '3.5'
services:
  sharelatex:
    image: sharelatex/sharelatex 
    networks:
      - mongo

networks:
  mongo:
    external: true