[Borgbackup] Borg & Maildir

[Sitaram Chamarty]

On Thu, Dec 29, 2016 at 02:45:21PM +0000, Iain Mac Donald wrote:
> 
> I have been running Borg for a week for our home server & family
> laptops and everything is working just great.
> 
> The one problem I foresee is restoring deleted emails. Emails are
> stored in Maildir format, filenames aren't seen by users, many
> folders have high daily activity and some folders contain 10s of
> thousands of files. Identifying which file to restore would be very
> difficult.
> 
> The only way I can think of doing it is by restoring a whole folder to
> a temporary location accessible to the IMAP server and then using an
> IMAP client to identify the deleted message and copying it back to the
> desired folder. Another approach might be doing text string searches on
> the Borg backups, within date ranges, but I'm not sure how to do that.
> 
> I realise this is a bit off-topic but I was hoping someone on the list
> might have a better solution to this problem.

Just use a mail client that can detect (and delete) duplicate
mails.  Once you have that, do what you said above -- i.e.,
restore the whole folder to a temp location -- then copy all
mails from there to the main one.  When that is done, delete
duplicates.

Thunderbird has an extension for this.  In mutt just use the
pattern '~=' and delete all mails with that pattern.  I'm sure
other mail clients have something.

The big downside to this is if you really only need a few mails,
but the maildir has tons of mails. You'd be processing all those
tons of mails just to grab one.

Playing around with 'formail' and message-IDs may also help.

regards
sitaram