[Evolution-hackers] kolab2 evolution plugin

[Sebastien Estienne <sebastien estienne gmail com>]

Hello,
I'd like to start working on a kolab2 connector for evolution, and i'd
like to have opinions of evolution hackers on the doability of the
project. I asked the question to kolab2 (proko2) developpers, his
answer is following

To give a short overview: of how kolab2 works:
-everything is stored in imap4 folders (mail/calendars/contact/notest)
-an xml format define these different elements in the a mail (rfc 822)
-imap folder use ANNOTATE to define there content.

the following link provide documentations about kolab2 storage format
and architecture:
http://www.kolab.org/documentation.html

one of the big advantage of kolab2 server, is that it's really easy to
setup and use compare to openxchange and opengroupware. You can
install it and get it running in 5 lines of shell. And it's based on
really common opensource software (apache/postfix/cyrus/php/openldap).
And kolab server has nothing kde specific.
So it seems to be the only opensource groupware server that is easy to
use and setup. (i tried openxchange + postfix/cyrus and opengroupware
+ postfix/cyrus/openldap)

(if some are interested i've a wiki about installing
kolab2/openxchange/opengroupware on debian sarge)
-----------------------------------------------------------------------------------
Question asked to the kolab2 mailing list:

> Could you give me an idea of the difficulty to do it for 2 goods
> developpers that have knowledge about xml/imap/c/linux (time?)

That is a though question.
Maybe Bo, David or Joon can say more.
(And it really is a topic for kolab-devel@ more than kolab-users@)

The estimation depends a lot of the current code,
especially what is there to use and how good it is.
Here is a quick brain dump, which garantees nothing,
but is betten then no answer:

There are two main parts of the problem:
    a) disconnected imap with annotations
    b) the Kolab2 XML storage format 
    c) interoperability details, like triggering pfbs

a) can be done in various degrees, from trying online imap
for testing purposes only (it will be considered an offensive client
in production environments, because bogging down the server)
to well designed syncronisation queues.
Depending on how much Evolution already does, I would 
roughly estimate say up to 6 personmonth. (So with two people
you might be able to do it in 4 month.)

b) Dedends on how Evolution saves events internally.
When knowing everything, 3 person month.
Usually you discover bugs in Evolution this ways, that you need
to fix. 

c) Hard to tell, there are many small but important details. 
(This probably is the biggest item.)
-- 
Sebastien Estienne