Default keys and aliases location on non-Unix platforms

[str4d]

The specification gives the Unix path ~/.config/age/* as the default location it looks for keys and aliases. How should this map to Windows and macOS? The directories Rust crate (which aims to follow per-OS conventions) appears to indicate the following as being approximately OS-shaped:

• Windows: C:\Users\Alice\AppData\Roaming\age tool\age\config\*
• macOS: /Users/Alice/Library/Preferences/com.age-tool.age/*

We could also go simpler by just using the known folders for program settings as the base:

• Windows: C:\Users\Alice\AppData\Roaming\age\*
• macOS: /Users/Alice/Library/Preferences/age/*

Thoughts? Is there somewhere else these should go? Are users expected to be editing these by hand (in which case maybe a Documents-like folder should be used, which is more accessible)?

[danlamanna]

FWIW, It looks like the Go team had a lot of discussion on this topic for the 1.13 release and produced os.UserConfigDir. Perhaps age should rely on that?

[str4d]

I scanned the discussion there and it seems like a reasonable approach. For my Rust impl to be compatible I'd need to manually detect macOS and handle it separately because of how the directories crate differs, but that's not too bad.

[Fastidious]

I think age should use $home/.config/age/ under macOS as well. Several applications share the same directory.

[FiloSottile]

For the record, we ended up removing the ~/.config/age path entirely, and replacing it with a recommendation that applications generate per-task keys and keep them in the application config path.