Stacks - Add the ability to pull and fill ${___} placeholders in compose files from Git

[LeVraiRoiDHyrule]

Is your feature request related to a problem? Please describe

Currently, the only way to fill in ${____} placeholders is to input them manually in Portainer UI. This becomes a problem when pulling a docker-compose.yml from Git, because it is still necessary to input those variables manually.

Adding a .env file in "additional paths", putting the .env in the root of the Git repository or next to the docker-compose.yml doesn't work.

It is currently possible to add a .env file to add env variables to containers, but there is no way to do the same for ${____} placeholders. This blocks from fully editing stacks from Git, re-deploying the full stack from the UI manually is still needed in case I need to change a placeholder value.

Describe the solution you'd like

The best solution would be to have a text field, similar to the one for "additional paths" but for ${____} placeholders. That way we can specify a .env for placeholders for the entire docker-compose.yml.

The current "additional paths" setting would remain unchanged. It would still be possible to add other .env files for adding them to specific containers with env_file : ____.env.

Describe alternatives you've considered

There is no alternative.

Additional context

This would be an very very useful addition for using Git with Stacks. Without it, there isn't much benefits of using Git with Stacks.

[LeVraiRoiDHyrule]

Hi, do someone know if this is doable ? Maybe I just didn't find how but if it is not possible, that would be an extremely interesting feature to add. Have a nice day.

[LeVraiRoiDHyrule]

This already works ! If a file is named .env in the same folder of the docker-compose.yml, it will use it to fill out the placeholders !

[ScottFries]

The main shortcoming with this approach is when you're trying to share an .env file across multiple stacks. E.g. most stacks I deploy make use of a common TZ, DOMAIN_NAME, and miscellaneous directory values. By allowing any arbitrary path(s) to .env files you can cluster related and re-used values together rather than manually replicating them across stacks (and having to maintain all copies of those values).

[yannduran]

Exactly what you've described @ScottFries, & for exactly the same reason that you mentioned, is what I've been trying to (unsuccessfully) do for my stacks. Like the OP I have a single repository with folders for each stack. I was just researching the stack_env file & came across this discussion.

I can't believe that this discussion was started in 2023 & here we are in January 2025 but we still can't share env files across stacks when pulling the stack info from a git repo.

Whether it's a bug, or is this way for a reason (& no I don't think Docker Swarm is a good enough reason for this to not work in normal stacks. Portainer just doesn't seem to be interested in enabling this to work the way we need it to work, which is very disappointing.