Problem trying to connect Mongodb via Docker-Compose with Robo3t. How to complete the connection?

Question

I want to make a connection through Robo3t of a Mongodb database that is running via Docker-Compose.

version: '3'

services:
  mongo-express:
    image: mongo-express
    container_name: mongo-express
    ports:
      - 8081:8081
    environment:
      ME_CONFIG_BASICAUTH_USERNAME: <usuario>
      ME_CONFIG_BASICAUTH_PASSWORD: <senha>
      ME_CONFIG_MONGODB_PORT: 27017
      ME_CONFIG_MONGODB_ADMINUSERNAME: root
      ME_CONFIG_MONGODB_ADMINPASSWORD: <senha>
    links:
      - mongo
    networks:
      - mongo-network

  mongo:
    image: mongo
    container_name: mongo
    environment:
      MONGO_INITDB_ROOT_USERNAME: <usuario>
      MONGO_INITDB_ROOT_PASSWORD: <senha>
    ports:
      - 27017:27017
    volumes:
      - ./datadir:/data/db
    networks:
      - mongo-network

networks: 
    mongo-network:
      driver: bridge

I’ve tried to change the authentication mechanisms and ports but gives the same message:

Cannot connect to the MongoDB at localhost:27017.

Error:
Authentication failed.

Answer 1

Your Docker-Compose is correct. The problem is in connecting to the database.

As specified in Docker Hub:

These variables, used in Conjunction, create a new user and set that user’s password. This user is created in the admin Authentication database and Given the role of root, which is a "superuser" role.

That is, when using the environment variables MONGO_INITDB_ROOT_USERNAME and MONGO_INITDB_ROOT_PASSWORD, the user is created as root in the database admin.

Therefore, it is necessary to specify admin in the field Database flap Authentication.