No, I don't think we should do this, and this definitely doesn't address docker/compose#745 (just shifts the problem from directory name or .env to the compose file)

@thaJeztah then I misunderstood the requirements set on docker/compose#745

@thaJeztah do you mean because it doesn't persist the project name in a separate file from the docker-compose.yml file, and/or because compose does not save the auto-generated project name into said separate file? This solution does allow persistence of the project name independently of choices that may affect other (not compose related) parts of a project (folder name, checking in a .env file), so I think it's fair to say it covers at least some of the use cases -- I think some clarification on what it's missing would be helpful.

@thaJeztah ok, reading more carefully your initial request docker/compose#745.

IIUC you're expecting we store "user session state" on filesystem aside the compose.yaml file so that user only has to set --project-name once and then all further commands will apply to the same project. We could obviously have docker-compose support some .docker-compose file in project directory as an implementation specific alternative to define project name, as well as some additional command flag to create this file. That could be nice (I'm not fully convince this is really useful, but why not ¯\(ツ)/¯ ?

That being said, comments on docker/compose#745 demonstrate we also have user who expect they can hard-code the project name in the compose file to make it fully deterministic. I think we can have both

• default project name defined in compose file
• if not set, default project name determined by implementation (docker-compose uses parent folder)
• project name set by some implementation-specific config file
• project name set explicitly by command

+1 to have an option to define name as part of the compose file. Indeed, it does not need to be the only option, but in many cases defining it inside the compose file is the most intiuitive and natural solution.
Then, ability to store project name passed by --project-name or other ways when compose up can be used to override the name passed in the compose file (that in turn also overrides default naming like based on parent folder).
Note that compose implementation also uses container labels to store project name, not sure about the interaction with this - but adding the name field in the compose file can be done quite independently of more "runtime" features happening related to storing project name after user executes compose up.

how do we expect it to work for cases when multiple Compose files are combined

Like other elements : if defined in an override file, will override.