Ability to specify cwd

[nettnikl]

I'd like to propose a new feature - the ability to specify the cwd of the backup process. This seems to be a recurring pattern to allow relative path based backups (a use case is described at https://forum.restic.net/t/backing-up-restoring-relative-paths/744). This would be quite easy, as the subprocess.call supports the cwd parameter.

[nils-werner]

Agreed, that might be handy to have.

I'm thinking of introducing it as something like _cwd: and deprecating arguments: in favor of _args:, to prevent collisions with restic commandline options now or in the future.

[nils-werner]

I have pushed a few changes to cwd-param. Have a go and see if it works as expected.

[nettnikl]

Will do, thanks for your quick reaction!

[nettnikl]

Hey, finally had a chance to test on my setup, sorry for the delay.
It works, in the dry run as well as in my real setup! Great job!
One thing that it'd like considered looking at the resulting configs however - maybe a default backup path of "." would make sense, maybe only in cases where a path is given via cwd? What are your thoughts on this (or do you see discussion potential for another issue)?
Thanks again!

[nils-werner]

Great to hear!

You mean a file

[home]
_cwd: ~

implies

[home]
_cwd: ~
_args: .

?

Hmm... I think woud prefer to not implement any default behaviour here, as using a cwd and then defining a path relative to it is definitely advanced usage that requires knowledge about how restic treats the two differently. In that case I think it would be best to make all the paths involved directly visible to the user.

[nettnikl]

Okay, i agree, i'm just looking for an option to have a "speaking" config file, as the idea of the option "_args: /path/to/backup" is not immediately clear for everyone. However, that has nothing to do with this request. I'll open a new ticket, this one is solved perfectly!

[nils-werner]

Lets keep this open until it has been merged into master.

[nils-werner]

Actually, I am playing with the idea of moving _cwd into the [backup.environ] group, because it is arguably an attribute of the execution environment, and not a command option or argument

[nils-werner]

Ok, I think I like it more that way: Your typical UNIX environment variables already contain $PWD that contains the current working directory. So it kind of makes sense to use this variable to change the cwd of restic:

[home]
_args: .

[home.environ]
PWD: ~

And you can also now cleanly override this value from the commandline

env PWD=~ crestic home backup

A small caveat: Normally, changing $PWD before running a command is not the same as changing the current cwd. Compare

(cd / && ls)
env PWD=/ ls

but I am ignoring that fact here.

[nettnikl]

While it technically is, i think it makes the config harder to read, which should also not be neglected. The current solution looks good to me - maybe you could show how the idiom i mentioned would look in with the alternative approach?

[nils-werner]

This is now in 0.8.0 and called _workdir:.