[Dovecot] dovecot dspam plugin using libdspam

[WJCarpenter]

It's none of my business, but here's a suggestion for more work for
somebody.  :-)

The idea behind the dspam plugin -- watching things move from folder
to folder -- seems very, very clever to me.  I wonder if it might have
wider applicability, even if we can't see what it is today?  Taking
account some of the performance concerns discussed way, way back, it
still seems like a good idea to separate out the watching part from
the processing part.

What if there were a generic "movewatcher" plugin which:

-- observed movements from one folder to another

-- configured with some kind of list or regexp or something for the
   source folders which were interesting/uninteresting (e.g., "SPAM")
   and likewise for the target folders (e.g., "Trash")

-- configured for some list of email header values to log

-- configured for some place/way to log those header values

-- configured for some format for logging with maybe %-escapes for
   interesting information (e.g., "%u" means the userid, "%s" means
   the source folder name, "%t" means the target folder name, "%hFoo"
   means the value of header "Foo", "%HFoo" means the string "Foo: "
   followed by the value of header "Foo").

Assuming everything interesting you would want to process is available
in one or more headers (in keeping with the Postmaster Code of Condut
Rule #2c: Thou shalt not look at content :-), you could log everything
interesting to some flat file (or FIFO) and write a completely
independent program to process that log.

For the particular case of dspam retraining, you're all good if you
have the dspam signature in the headers.  (I don't know how you end up
without that except during transition to dspam, so I'm not worried
about retraining from the raw message.)
-- 
bill-dovecot at carpenter.ORG (WJCarpenter)    PGP 0x91865119
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