env_file, environment and .env only work on the current working directory

[jolly-jump]

Ok this is hard to explain: I wanted to integrate the docker-compose into my greater docker-compose containing an nginx-reverse-proxy and more...

Normally this works out of the box, this time I stumbled across the usage of env_file and the .env-file:
My conclusion is: I have to put the .env file where the docker-compose file is, and I cannot do the following:

  immich-server:
    container_name: immich-server
    image: altran1502/immich-server:release
    restart: always
    entrypoint: [ "/bin/sh", "./start-server.sh" ]
    env_file:
      - ./immich/.env
    volumes:
      - "${UPLOAD_LOCATION}:/usr/src/app/upload"
    environment:
      - NODE_ENV=production
    depends_on:
      - immich-redis
      - immich-db

The problem is not that I cannot rename the .env-file or put it in a sub-directory which I usually do. The containers still get the env-variables set.
The problem is, that the replacement in the docker-compose file then does not take place anymore.

Although this here suggest, that you could do what I wanted,

The .env file should be placed at the root of the project directory next to your docker-compose.yml file. You can use an alternative path with one of the following methods:

The --file option in the CLI
The --env-file option in the CLI
Using the env_file attribute in the Compose file

The last bit just does not work: If i put the env_file to point to some other file, the TAGS get not replaced in the docker-compose.yml.

The SA-Answer here explains what I experience, while the other answers there seem to miss the point.

My point for the installation is:

• Maybe one should not use env_file and use the values in .env to replace variables in the docker-compose since they serve different purposes.
• On the other hand, I have no better idea than to hardcode the UPLOAD_LOCATION in the docker-compose.yml once it is set up and rename the variables DB_USERNAME to POSTGRES_USER etc. in the .env file. Then the .env-file serves only the purpose for the containers, not for the docker-compose file and can be moved and renamed however one wants.

Just in case, someone tries the same like me :)