Docker Compose doesn't load .env file and incorrect DATABASE_URL configuration

[SureshPradhana]

Overview:

There are two main issues in the current Docker setup:

1. The .env file is not being loaded, causing missing environment variables during runtime.
2. The DATABASE_URL uses host.docker.internal:35000, which leads to connection errors within the Docker network.

These issues prevent the backend service from properly connecting to the PostgreSQL database when using Docker Compose.

Environment:

• OS: Arch Linux
• Docker Version: 27.0.3
• Docker Compose Version: 2.28.1

Actions Needed:

• [ ] Load .env file: Update the docker-compose.yml to include the env_file directive.
• [ ] Update DATABASE_URL: Modify the DATABASE_URL to use the correct hostname within the Docker network (db:5432).

Proposed Fix:

1. Load .env file: Add the following to the api service in docker-compose.yml:

   env_file:
    - .env

2. Correct DATABASE_URL: Update the DATABASE_URL in docker-compose.yml:

   DATABASE_URL=postgres://postgres:postgres@db:5432/bloom

[SureshPradhana]

Hi, can you confirm if the issue I reported is correct? If so, I'd like to work on it.

[kyleecodes]

1. The .env file is not being loaded, causing missing environment variables during runtime.
2. The DATABASE_URL uses host.docker.internal:35000, which leads to connection errors within the Docker network.

Hi @SureshPradhana, thank you for your suggestion, and patience while we were out of office. Can you share the exact connection errors you experienced? They might be specific to your set-up. But we aim to support all environments, so it's important we learn what is going on here.

As for loading env vars, I agree they should be mounted to the volume / loaded at runtime, as you demonstrated. Our current set-up isn't best practice, this would be more secure and flexible.

[SureshPradhana]

Hi @kyleecodes,

Thanks for the feedback. Here are the connection errors I faced:

• Issue: Connection refused when using host.docker.internal:35000 for PostgreSQL.

  bloom-backend   | [Nest] 39  - 08/29/2024, 11:20:24 AM   ERROR [TypeOrmModule] Unable to connect to the database. Retrying (1)...
  bloom-backend   | Error: getaddrinfo ENOTFOUND host.docker.internal
  bloom-backend   |     at GetAddrInfoReqWrap.onlookupall [as oncomplete] (node:dns:120:26)
  bloom-backend   | [Nest] 39  - 08/29/2024, 11:20:27 AM   ERROR [TypeOrmModule] Unable to connect to the database. 

i use linux found out that On Linux, host.docker.internal is not available out-of-the-box. Instead, you might need to use the host’s IP address or configure Docker networking to access the host machine.

In a Docker Compose setup, host.docker.internal isn't suitable because PostgreSQL runs in a Docker container. The recommended approach is to use postgres://postgres:postgres@db:5432/bloom to connect to the PostgreSQL service within Docker.