[Kolab-devel] drawbacks if kolabmailboxfilter.php is removed

[Fabio Pietrosanti]

Hi,

i was reading kolabmailboxfilter.php and seen that it basically do:
- check parameters passed by postfix
- make sure there is a recipient
- make recipients lowercase
- enforce allow_sender_header directive
- verify if it's an ical essage
  - if it's icall
    - call resmgr_filter (which check if this is the KolabHomeServer of
user and do several calendaring jobs via imap)
    - add header X-Kolab-Scheduling-Message: TRUE
- deliver message trough LMTP

I'm wondering if would make sense to move all those functionality to
kolabfilter.php and let postfix do the LMTP delivery to Cyrus LMTP
Server itself.
In that way there will be only "one" filter that in a scalable
environement could also be separated from the rest of infrastructure.
Having only one filter would also be benefit for performance.


I'm saying that because i need to integrate OpenPec
(http://www.openpec.org which is in italian), a components that receive
email via SMTP/LMTP and deliver it to LMTP.

OpenPEC "has to be" the LMTP delivery cause it need to certify that an
email was delivered to the mailbox of the user.
The certification is done via a digital signature email receipt sent to
the sender and to the sender certified isp.
This methods is recognized by italian law of "Certified electronic
Email" that has has been submitted to european community as
infrastructure for Certified Email Service and perhaps will be proposed
as standard to other european community state.

Having kolabmailboxfilter.php has the components that do the final LMTP
delivery it's difficult to integrate OpenPEC that need to be the
certified component that guarantee that the email was delivered to the
user mailbox.
I cannot move OpenPEC after kolabmailboxfilter.php because it need to
receive all email trough content-filter directive of postfix.

In such situation, would be possible to move the kolabmailboxfilter.php
functionality inside kolabmailfilter.php?

This would also provide a good performance boost.

Waiting for comments

Fabio