Compose: ".env" file not read relative to docker-compose.yml file

[andrerom]

global/default ".env" file is a great feature, allowing to set defaults for env variables without hardcoding reference to it inside each and every service definition using env_file, or having to wrap docker-compose in script to accomplish this.

However it does not seem to take folder of docker-compose.yml file into account, as implied by the doc:

Compose supports declaring default environment variables in an environment file named .env, _and placed in the same folder as your compose file_.

Example:

docker-compose --verbose -f bin/.docker/docker-compose.yml up -d --no-recreate
compose.config.config.find: Using configuration files: ./bin/.docker/docker-compose.yml
WARNING: compose.config.environment.__getitem__: The DATABASE_USER variable is not set. Defaulting to a blank string.
WARNING: compose.config.environment.__getitem__: The DATABASE_PASSWORD variable is not set. Defaulting to a blank string.
WARNING: compose.config.environment.__getitem__: The DATABASE_NAME variable is not set. Defaulting to a blank string.
docker.auth.auth.load_config: File doesn't exist
compose.cli.command.get_client: docker-compose version 1.7.0, build 0d7bf73

Suggested behavior

Maybe it should look for it in following order _(all before loading any docker-compose.yml files)_:

• pwd _(execution folder)_
• folder of 1st docker-compose.yml
• [ ... ]

This would allow dev envimrnets to override prod env in example below with .env file in dev/ folder:

 export COMPOSE_FILE="docker-compose.yml:dev/docker-compose.yml"
docker-compose up -d --no-recreate

[andrerom]

Discussions with @dnephin on IRC revealed that this is most likely a doc issue, as it also allows setting COMPOSE_FILE implying it by design can only be taken from current working directory.

[dnephin]

2594 would provide one way to set the directory which contains the .env file

[andrerom]

True, I was about to suggest a flag to override which env to use, but this would solve it as well.

[cinemast]

In my opinion, changing the documentation does nit fix this issue. If you are combining multiple containers with the -f option, there is no way to use their local .env files.

Beside that, the documentation at https://docs.docker.com/compose/compose-file/ still promotes a different (and in my opinion more useful) behavior.

[ghost]

In my opinion, compose should just always check for a .env in the directory where the .yml is located or give the ability within the compose yml itself to point to an env file anywhere.

[shin-]

As answered in #5481, the reason it works like this is because the .env file also allows to define the COMPOSE_FILE variable, which obviously needs to be read before we can evaluate where the Compose file is located.