Server-side filtering to subfolder for all users (spamassassin)

Question

Hello,
I am trying to integrate a 3rd-party spam filter/virus scanner, it is just spamassassin/amavisd-new running on a front-end box that adds an X-Spam-Flag: YES header to the message before passing it on. This works great on our current postfix/cyrus-imap system using individual cyrus sieve server side filters to look for the flag and move the message into the user's spam folder.
My question is how to do this in a universal way on OCS, I have been reading through the docs and think server-side filters are the answer, but I can't seem to find a way to set up a system-wide filter that will put the incoming message into the recipients' spam subfolder. Does anyone have any clues on this? I think the key here is to somehow be able to use the recipient name as a variable to pass as a parameter to the moveto action, but I can't see a way to do this. Any pointers would be appreciated.

Answer 1

You can do this in a single system wide rule, but it's undocumented and technically unsupported.
First of all, checking the spam-flag in a system side Deliver rule is straightforward:
<condition>
<attribute tag="xheader" param="X-Spam-Flag"/>
<operator caseSensitive="no" op="stringequal"/>
<operand>YES</operand>
</condition>
(Checking on the subject is OK too, if you rewrite it through SpamAssassin.)
Then to move to a folder, you'll need an external PL/SQL action since the full folder name will vary for each user:
<action>
<command tag="call"/>
<parameter>SpamCheck.moveMsg</parameter>
<parameter>parameter1</parameter>
<parameter>parameter2</parameter>
</action>
Then the tricky part is the Pl/SQL to do the move, using the undocumented es_ga.g_username variable. This is the only way to know which mailbox context you're currently in for the deliver event at the system level. Without this, you need a separate rule for every user. Here's the bare bones of a procedure that would do it.
procedure moveMsg(p_eventid in integer,
p_sessionid in integer,
p_msgobj in mail_message_obj,
myparam1 in varchar2,
myparam2 in varchar2,
p_status out number)
is
this_user varchar2(255);
mList MAIL_MESSAGE_LIST;
Begin
this_user := es_ga.g_username;
mList:=MAIL_MESSAGE_LIST(p_msgobj);
mail_folder.move_messages(p_sessionid, mList, '/' || es_ga.g_username || '/ServerMove');
end MoveToSpam;
You probably want to add some exception handling, etc. to that ;-) More info on the Pl/SQL API in general is in the Mail Application Dev Guide.