[Dovecot] v1.2 development tree started

[Joseph Yee]

Hi Timo,

First of all, dovecot is great! :)

Question on CONDSTORE.  I haven't re-read RFC to confirm, isn't 
CONDSTORE operates under switch mode with command ENABLE?  So that IMAP 
client needs to request such capability.  Maybe I mixed up with another 
IMAP command.

Thanks
Joseph

Timo Sirainen wrote:
> Updates:
> 
> On Mon, 2008-06-09 at 05:51 +0300, Timo Sirainen wrote:
>> I merged all the new features and latest v1.1 changes under one tree:
>>
>> http://hg.dovecot.org/dovecot-1.2/
> 
> Nightly snapshots are also from v1.2 code tree nowadays.
> 
>> 1. CONDSTORE extension is probably the largest change. It adds new
>> "modification sequences" for messages that increase whenever the
>> message's metadata changes.
>>
>> I'll probably have to reimplement the way modseqs are calculated,
>> because modseqs will be very useful when implementing replication and
>> the current way just doesn't work with it. If modseq-supporting clients
>> see the current modseqs and later the server gets upgraded to new
>> modseqs, the clients will most likely break. So this change should be
>> done for v1.2.
> 
> Modseq changes are implemented. The only issue with CONDSTORE is that
> STORE UNCHANGEDSINCE command doesn't atomically check-and-update.
> Implementing the atomicity should be pretty easy since there is a
> similar check already in the code. The largest issue with it is changing
> APIs enough to support returning back which messages failed the STORE.
> Still should be pretty easy.
> 
>> 4. Virtual mailboxes should work fast after mailbox is opened. The
>> initial opening could use several optimizations though. It could
>> probably share some code with QRESYNC to avoid the full initial search
>> (storing each backend's modseq to index header). Also if search
>> parameters don't contain any dynamically changing data, there's no point
>> in searching the old messages.
> 
> Implemented initial opening optimizations. I haven't done much testing
> though, other than it appears not to crash and appears to work with
> simple tests. :) So the current implementation should be as fast as it's
> possible to make it.
> 
>> The current design doesn't allow changing the search parameters or list
>> of mailboxes, otherwise it breaks more or less badly. I guess I could
>> add code to check if the dovecot-virtual file's mtime has changed and if
>> so make it do a full resync. This anyway means that there's no way to
>> support wildcard mailbox names (e.g. "all mailboxes"). But does anyone
>> really want that (yet)? It'll anyway be faster/easier to implement once
>> mailbox list indexes are implemented.
> 
> Changing mailbox list is now detected and handled, as well as
> UIDVALIDITY changing in mailboxes. Mailbox list wildcards wouldn't be
> all that difficult to implement anymore if someone wants them, but until
> then I don't think I'll bother.
> 
> Changing search parameters still isn't detected though. Maybe it could
> store a MD5 sum of the search parameters in the header and if it changes
> rebuild the entire mailbox.
> 
>> I'll still have to add a new X-MAILBOX search parameter which can be
>> used to test what the backend mailbox name is. This will be especially
>> useful with INTHREAD extension. I guess it wouldn't hurt to have FETCH
>> X-MAILBOX if someone wants it.
> 
> Oh, almost forgot about this one.
> 
>> 6. INTHREAD extension isn't started yet, but I'll start it soon.
>> Hopefully won't be too tricky to get it working with virtual mailboxes
>> and CONTEXT=SEARCH..
> 
> This one is the last major unimplemented v1.2 feature. After that I'll
> start finishing, optimizing and stabilizing the features for a v1.2
> release (as well as start v2.0/replication coding). I'm hoping for
> v1.2.0 release by the end of this summer.