How can I connect to a mongoDB cloud cluster from docker container?

Question

I am developing a django-react app and using a mongoDB cluster to store data. When I run the app without using docker, I am able to make requests to the database without issue. However, when I run the docker containers (one for my backend and one for my frontend) I run into this error on the backend:

File "/usr/local/lib/python3.9/site-packages/pymongo/topology.py", line 215, in _select_servers_loop

raise ServerSelectionTimeoutError(

pymongo.errors.ServerSelectionTimeoutError: localhost:27017: [Errno 111] Connection refused, Timeout: 30s, Topology Description: <TopologyDescription id: 5f9ece0f7962ee81cb819b63, topology_type: Single, servers: [<ServerDescription ('localhost', 27017) server_type: Unknown, rtt: None, error=AutoReconnect('localhost:27017: [Errno 111] Connection refused')>]>

I have the mongodb host in both mongo_client.py and settings.py. In settings.py I have:

DATABASES = {
        'default': {
        'ENGINE': 'djongo',
        'NAME': '<mydb>',
        'HOST': 'mongodb+srv://mike:<mypassword>@cluster0.5u0xf.mongodb.net/<mydb>?retryWrites=true&w=majority',
        'USER': 'mike',
        'PASSWORD': '<mypassword>',
    }
}

My docker-compose yaml looks like:

version: "3.2"
services:
    portalbackend:
        restart: always
        container_name: code
        command: bash -c "python manage.py makemigrations &&
                        python manage.py migrate &&
                        python manage.py runserver 0.0.0.0:8000"
        build:
            context: ./PortalBackend/
            dockerfile: Dockerfile
        ports:
        - "8000:8000"
        networks:
        - db-net

    portal:
        restart: always
        command : npm start
        container_name: front
        build:
            context: ./portal/
            dockerfile: Dockerfile
        ports:
        - "3000:3000"
        stdin_open: true
        depends_on:
        - portalbackend
        networks:
        - db-net

networks:
    db-net:
        driver: bridge

Do I need to create a container for mongodb? I originally tried that with a local mongodb instance but I was running into the same issue, so I tried rolling with a cluster. Still running into the same problem.

Answer 1

No you don't need to add a mongo container, as your database is in Atlas.

Please see my answer posted yesterday for a similar problem: Django + Mongo + Docker getting pymongo.errors.ServerSelectionTimeoutError