Docker Compose Mongo with Mongo Express

docker-compose.yml

version: "3.5"

services:
  mongo:
    image: mongo:latest
    container_name: mongo
    environment:
      MONGO_INITDB_ROOT_USERNAME: admin
      MONGO_INITDB_ROOT_PASSWORD: admin
    ports:
      - "0.0.0.0:27017:27017"
    networks:
      - MONGO
    volumes:
      - type: volume
        source: MONGO_DATA
        target: /data/db
      - type: volume
        source: MONGO_CONFIG
        target: /data/configdb
  mongo-express:
    image: mongo-express:latest
    container_name: mongo-express
    environment:
      ME_CONFIG_MONGODB_ADMINUSERNAME: admin
      ME_CONFIG_MONGODB_ADMINPASSWORD: admin
      ME_CONFIG_MONGODB_SERVER: mongo
      ME_CONFIG_MONGODB_PORT: "27017"
    ports:
      - "0.0.0.0:8081:8081"
    networks:
      - MONGO
    depends_on:
      - mongo

networks:
  MONGO:
    name: MONGO

volumes:
  MONGO_DATA:
    name: MONGO_DATA
  MONGO_CONFIG:
    name: MONGO_CONFIG

The above error/warning didn't prevent me from running, can be ignored if this is for learning.
The "wait-for" fixed my issue, thanks so much for this example @adamelliotfields!

You can also use restart: unless-stopped instead of overwriting the entrypoint.

I get a connection error that seems due to the fact that mongo-express does not wait for mongodb to start (i can connect successfuly with compass to localhost:27017)

mongo-express    | (node:7) UnhandledPromiseRejectionWarning: MongoNetworkError: failed to connect to server [mongo-server:27017] on first connect [Error: connect ECONNREFUSED 172.19.0.2:27017
mongo-express    |     at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1144:16) {
mongo-express    |   name: 'MongoNetworkError'
mongo-express    | }]

  mongo-server:
    container_name: mongo-server
    image: mongo:4.4.5
    networks:
      - weally
    ports:
      - "27017:27017"
    volumes:
      - type: bind
        source: /var/weally/mongodb
        target: /data/db
#      - /var/weally/mongodb:/data/db
#      - ./config/mongodb.conf:/data/configdb
    restart: always

  mongo-express:
    image: mongo-express:latest
    container_name: mongo-express
    environment:
      ME_CONFIG_MONGODB_SERVER: mongo-server
      ME_CONFIG_MONGODB_PORT: "27017"
    ports:
      - "8081:8081"
    networks:
      - weally
    depends_on:
      - mongo-server

You can also use restart: unless-stopped instead of overwriting the entrypoint.

works too and it's a cleaner solution imo.

Think of the wait-for script as like a Kubernetes readiness probe. Kubernetes wont serve traffic to a pod that isn't ready.

That said, you can certainly get by with restart policies if you don't mind the log spam.

Also check out the READMEs for mongo and mongo-express on Docker Hub - they include everything in this Gist and more (and they aren't 4 years old).