Support global configuration files in /etc/rustic/

[pheki]

I think it would be great to have global config files in /etc/rustic/ which could be used for backups by "system" users (which don't have a home directory) or configurations shared between users, so for example one user could create the backup and other users would still be able to access it.

The configuration files at ~/.config/ would have precedence over /etc/.

If you're interested, I'm willing to find some time and give this a try.

[aawsome]

I also like the idea. Especially with the possibility to use other config file, see use-profile, there is a good use case to have global config options and maybe per-user config options referring to to the global ones.

Some notes:

• We are currently about to refactor rustic, see Refactor into rustic_core library, rustic cli library and rustic application part #617. Maybe you should wait for this to finish or base on this PR.
• Currently https://docs.rs/directories/latest/directories/struct.ProjectDirs.html is used. Maybe you can find a better crate which supports user/global config dirs.
• Please have in mind that we should stay compatible with non-linux systems, i.e. MacOS and Windows.

[pheki]

We are currently about to refactor rustic

Oh, good to know! Waiting is good to me

• Please have in mind that we should stay compatible with non-linux systems, i.e. MacOS and Windows.

Hmmm totally forgot about Windows... Here are some options I've gathered:

Windows:

• %ProgramData%\rustic\config (resolves to C:\ProgramData\rustic\config)

MacOS:

• /etc/rustic/
• /usr/local/etc/rustic (for software installed using homebrew)
• /Library/Application Support/com.rustic.rustic (I don't know the actual values you're using here but you get the point)
• /Users/Shared/* (could use .config or Library/ApplicationSupport)

For MacOS I think /etc/ and /usr/local/etc are the best option (we could just check both directories).

Currently https://docs.rs/directories/latest/directories/struct.ProjectDirs.html is used. Maybe you can find a better crate which supports user/global config dirs.

Just opened a issue there: dirs-dev/directories-rs#82

[aawsome]

Yes, would be great to have this implemented upstream. But I'm also fine with adding global config support to rustic until it's conveniently supported by a crate.

[aawsome]

FYI, #617 has just been merged.