[Dovecot] Idea: POP3 deletion as a flag

[Timo Sirainen]

On 3.5.2013, at 20.30, Tom Hendrikx <tom at whyscream.net> wrote:

> On 03-05-13 18:49, lst_hoe02 at kwsoft.de wrote:
>> 
>> Zitat von Timo Sirainen <tss at iki.fi>:
>> 
>>> GMail doesn't delete mails when POP3 client issues a DELE command for
>>> it. Instead they just become invisible for future POP3 sessions, but
>>> they still exist for IMAP/webmail. The same could be implemented
>>> pretty easily for Dovecot:
>>> 
>>> - Add a new setting to enable this: pop3_deleted_flag = $POP3Deleted
>>> - When DELEting a message, add this flag to the message.
>>> - When listing messages, skip all messages that have this flag.
>>> - Also hide this flag from IMAP clients(?)
>>> 
>>> Thoughts? Probably 20 lines of new code.
>> 
>> Hmm, this would lead to every increasing mailboxes for POP3 only users.
>> What about this
>> 
>> - Use some setting to express that POP3 deleted mail should be IMAP
>> mark-as-deleted
> 
> This conflicts with (many) IMAP user agents that don't use
> mark-as-deleted but have some version of 'move to trash folder' instead.
> I do agree that it's probably the Right Way (tm) :)

Depends on what purpose this feature is going to be used for. Many POP3 users don't actually want to delete the mails, they just want to download them, and their client just happens to delete the mails as well. They might still want to use webmail occasionally to find any old mails. For that purpose \Deleted flag wouldn't be ideal. But, with this setting it would be possible as well: pop3_deleted_flag = \Deleted (although that would need a few more lines of code).

>> - Skip messages marked as deleted with POP3, maybe even as default?
>> 
>> With this on IMAP access you clearly see what is going on. Also if you
>> delete Messages by IMAP they won't get downloaded by POP3. This would
>> also fit with mail providers doing an "IMAP" expunge/purge on a fixed
>> timebase.

If mail is expunged from IMAP, it also is expunged from POP3 in any case.