Allow to use custom snapshot command

[martyone]

No description provided.

[martyone]

Screenshot of the added UI controls:

[aplaice]

Interesting! Thanks! (Thanks also for the screenshot and for keeping the change as self-contained as possible.) Good catch on the ABC class method!

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Some comments:

I believe logger in custom_command_repo.py is no longer used?

(Nitpicky, sorry!) I think that it'd be better if CUSTOM_SNAPSHOT_COMMAND (and the lower-case variants) were renamed in the order SNAPSHOT_CUSTOM_COMMAND. (I believe that we currently are sort-of namespacing the config keys (import_, export_, snapshot_), which makes it easier to read.) (Hopefully it should be a trivial recursive search/replace.)

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I think that the "docs" (on the right side of the config UI) should be clarified for the default case — something to the effect of "if left blank runs normal procedure". The description for the env variable is also IMO slightly too concise.

Maybe something like:

Optional shell command to run instead of the normal `git-commit` procedure. The `CROWD_ANKI_COMMIT_MESSAGE` environment variable for the shell command will be set to the commit message that would be used normally.

Default: Blank, so the normal `git-commit` procedure is run.

(Maybe "built-in git-commit procedure" instead of "normal git-commit procedure?)

Further, I believe that it would be better for the field in the UI to be labelled fully "Snapshot custom command" (and also in the "docs"). (Yes, it's the "snapshot" section, so it should be obvious, but given that people often just quickly glance through, it's better to be explicit. It's also more consistent with the previous cases, (e.g. "snapshot path") where we repeat "snapshot".)

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Sorry about the nit-picks!

[martyone]

@aplaice Thanks for review and suggestions! Updated.

I did a bit differently in case of the command, because the command overrides just one aspect of taking a snapshot, but using the wording "snapshot custom command" would imply (to me) that it overrides it completely.

[aplaice]

Thanks very much!

"snapshot custom command" would imply (to me) that it overrides it completely.

Yeah, you're right. Good call! Thanks!

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I'll leave this open for a short while in case anybody has further thoughts, and then merge!