dovecot - May 2012 - plugin: Don't allow deleting the last instance of a mail

Before beginning to code it, does anyone have any related ideas that could be
useful before starting it?

Mainly what I'm intending to do is to write a plugin for mdbox storage that
allows users to expunge mails in a specific namespace only if there are other
instances for the mail. So basically:

 * Users can't accidentally delete mails (in shared mailboxes)
 * Users can still move mails within folders

For v2.1 this can be implemented only to a specific storage backend, so at least
for now only mdbox will support it. Maildir and sdbox support would also be
possible by looking at hard link counts. Race conditions would allow deleting
the mails, but that's unlikely to be an issue since the main point is to
avoid accidental deletions that shouldn't be attempted in the first place
anyway.

Am 15.05.2012 20:57, schrieb Timo Sirainen:
> Before beginning to code it, does anyone have any related ideas that could
be useful before starting it?
> 
> Mainly what I'm intending to do is to write a plugin for mdbox storage
that allows users to expunge mails in a specific namespace only if there are
other instances for the mail. So basically:
> 
>  * Users can't accidentally delete mails (in shared mailboxes)
>  * Users can still move mails within folders
> 
> For v2.1 this can be implemented only to a specific storage backend, so at
least for now only mdbox will support it. Maildir and sdbox support would also
be possible by looking at hard link counts. Race conditions would allow deleting
the mails, but that's unlikely to be an issue since the main point is to
avoid accidental deletions that shouldn't be attempted in the first place
anyway.
> 
Hi Timo, is this feature often asked by dovecot-users ?
or are there special reasons for hacking it now, perhaps other stuff is
more urgent...
-- 
Best Regards

MfG Robert Schetterer

Germany/Munich/Bavaria