Re: Gnus Own-Cloudy?

[Eric Abrahamsen <eric@ericabrahamsen.net>]

Eric Abrahamsen <eric@ericabrahamsen.net> writes:

> Dan Christensen <jdc@uwo.ca> writes:
>
>> Eric Abrahamsen <eric@ericabrahamsen.net> writes:
>>
>>> But I would have thought that the active values for each group are
>>> stored on disk, so if you don't copy those over as well, Gnus will get
>>> confused about how many messages are in each group.
>>
>> For accessing an IMAP server, there's no need to sync Gnus data.  That's
>> sort of the point of using IMAP for your mail:  multiple clients can
>> independently access it and stay in sync with each other via the IMAP
>> server.
>>
>> Eric S Fraga <e.fraga@ucl.ac.uk> writes:
>>
>>> but as you have a local server on each system, they may be numbering
>>> messages differently depending on how they synchronise with the real
>>> IMAP server.  As a result, the counts and various data structures stored
>>> within the newsrc.eld file may not be consistent between machines?
>>
>> Right.  When you are accessing two different IMAP servers (even if
>> they are synced behind the scenes), you definitely don't want to
>> sync the Gnus data, since article numbers won't match.  For example, if
>> you tick an article in once Gnus instance, a different article may show
>> up as ticked in the other.
>
> Okay, I've received (and marked) a bunch of mail on the desktop (now my
> primary machine), after not having touched the laptop for a day. Right
> now the desktop's Gnus installation is showing a single unread message
> in one account's INBOX. I haven't copied any Gnus-related files from
> desktop to laptop.
>
> Now I go to my laptop, boot, run isync, then start Gnus. I get the
> unread counts that I would expect if Gnus was keeping track of which
> messages I'd read _on this machine_. Except for the sent mail folder of
> one of my accounts, which shows 3000+ unread messages, a number that
> doesn't seem to correspond to anything.

After thinking about this for a bit, I think I have a partial
explanation, and it's related to Gmail's emulation of IMAP folders.

I do client-side splitting. So I sync gmail with dovecot, then check
mail with Gnus. Gnus splits the mail, and tells dovecot to *remove* the
split mail from INBOX, and put it into another folder.

Next time I sync, dovecot and isync tell gmail to do the same thing. (I
don't know how IMAP works -- is it a "move" operation, or a "remove from
one group and add to another" operation? And when does the \Seen flag
get added?)

Gmail only does half of what it's told: it "adds" the new folder to the
message (as a label), but doesn't remove it from INBOX. This explains
the slowly-diverging folder message counts between my dovecot and Gmail.
It also helps explain the high unread-message count in my Gmail inbox
(via webmail): the messages must be first getting moved, then flagged as
\Seen, so the message that stays behind in Gmail's INBOX never gets
flagged.

When I sync on another computer, Gmail now has two copies of the
previously-split messages: one still in the INBOX, and one in the
destination folder, and both of these messages come down to dovecot,
then to Gnus. From what I can tell, neither has been marked \Seen, as
they show up as unread in both places in Gnus.

This still doesn't explain the shifting UID numbers, though.

Perhaps this is something I can fix by changing how isync talks to Gmail
(ie, sync directionality and all that). I don't know.

E

> The UIDs seem to remain the same -- at least my earlier ticked messages
> are the same on both machines. But I'm having another issue with
> something in my mail chain (gmail <-> isync <-> dovecot <-> gnus)
> re-setting UIDs for previously received messages, something that I just
> reported yesterday on the isync mailing list[1]. I can see now that, after
> I did a couple of syncs concurrently on both machines, mail I received
> on the laptop is not appearing on the desktop -- presumably because the
> UID of the message was changed, then incremented, but the UIDVALIDITY of
> the folder was untouched. This is a pretty big bug, but in which I'm not
> sure.
>
> Lastly, and also weird: I signed up for an outlook.com account so I
> could test the other issue, about searching for non-ascii characters via
> IMAP. I connected Gnus to that account directly, not via isync/dovecot.
> When I first restarted Gnus, it showed the unread count for that
> account's INBOX as 10004, which was the most recent UID, not the unread
> count (why outlook starts its UIDs at 10000 I don't know). After
> clearing that, it's behaving normally.
>
> So something weird is happening, or many weird things. Gnus has
> obviously got some remaining strangeness about group unread counts, but
> I'm inclined to blame the shifting UIDs on the interaction between
> dovecot, isync, and gmail. The whole thing is a mystery to me. I hope
> Oswald will respond on the isync list, and I'll look into Gnus' unread
> counts this weekend. Otherwise, it's back to work!
>
> Thanks,
> Eric
>
>
> [1]: http://sourceforge.net/p/isync/mailman/message/33402006/