Auto-create the dirs

[jaraco]

The app_paths project supports an additional interface (property) that will ensure the directory exists before returning it (alongside the classic interface where it's the caller's responsibility to create it). Having this interface is very convenient. Could platformdirs implement something similar?

[gaborbernat]

If you fill a PR for it sure 👍

[ThomasWaldmann]

I initially had a thumbs up on the top post, but I just removed it again.

We are currently working on adopting platformdirs to borgbackup and while dealing with the respective code, it became clear to me that:

• auto-creating should not be fully automatic, but just if requested
• whether one actually uses the path returned by platformdirs might depend on other circumstances also, e.g. whether some application-specific overriding env vars are set or not. if such an override happens, one would not want to auto-create a useless directory elsewhere just as a side-effect of querying the path.

[jaraco]

Indeed. The way app_paths gave control was by exposing separate properties. Ex. user_data would auto-create while user_data_path would not.

[ThomasWaldmann]

Hmm, is a separate property good enough considering the mode of the auto-created directory?

[jaraco]

In my cases, mode was never a consideration. Maybe it will become relevant, but hasn't yet.

[smsearcy]

The basic use case of the default mode would suffice for my use cases as well, and I think this would be a very nice to have feature.

A couple thoughts/questions:

• For the functions like platformdirs.user_data_dir(), would an additional create: bool = False keyword parameter make sense? (That could also include mode support.)
• For the PlatformDirs class, does it make more sense to have additional properties or having a create: bool = False keyword parameter in the __init__()?

[gaborbernat]

Yeah, a PR with that effect would be accepted.

[gaborbernat]

Though instead of create I'd use ensure_exist. Feels more like what the stdlib would use https://docs.python.org/3/library/os.html#os.makedirs; and implies it would only create it if does not already exist.

[Akuli]

If I do PlatformDirs("foo", "bar", ensure_exist=True), will it create all the different directories (config, cache, log, site cache, site data, ...) or only the ones I use?

I hope only the used directories will be created. It means that accessing a property will magically create a directory, but it doesn't seem too magical to me.

Edit: Nevermind, this was already discussed above. Should have read more carefully...

[smsearcy]

FYI, I finally started a branch for this. I need to write some tests then I'll open the PR.

[gaborbernat]

Thanks 👍