Incremental backup

[rchen19]

Is your feature request related to a problem? Please describe.
Currently you cannot point output path to an existing directory, and bagoup insist on creating an empty directory and backup everything.

Describe the solution you'd like
Would it be possible to backup incrementally, i.e. find new messages sent and received after the last backup, and add these new ones to an existing backup directory?

Additional context
Just a thought. This may be a bit difficult to implement, it will need either 1) keep an internal database on which messages it has already backed up, or 2) scan the backup files to determine which ones are old, prior to each backup.

[tagatac]

Thanks for the issue.

This could actually be feasible by writing a pointer file containing the timestamp of the last exported message, with 2 caveats:

1. It would only work for text file backups. The concept of appending wouldn't work well with PDF exports.
2. This would put a backward-compatibility constraint on bagoup (unless the pointer file also contains the bagoup version, and incremental export is only supported within the same version).

To other users: please upvote or comment if you would use this functionality.

[rchen19]

I actually do not see upvote option here, is it some new feature of GitHub?

[tagatac]

[rchen19]

Ah I see, emoji reactions 😂