[Mailman-Developers] How to share Mailman extensions

[Ellen Spertus]

I'm wondering how best to share my Mailman extensions, assuming they're 
useful to anyone besides me.  For now, I've created a project at 
sourceforge.net (http://sourceforge.net/projects/dsub/) and released a 
tarball containing the files I've modified or created.  The code is 
pre-alpha at this point.  I hope to have an alpha version by the end of 
this weekend.  While I hope my changes will eventually be incorporated into 
Mailman, the time has clearly not yet arrived.  Any advice on whether to 
start my own branch of the Mailman CVS tree now or to keep hacking 
separately until when and if my code is incorporated?

When I upload the alpha code, I'll also post a design doc and ask for 
criticism.

I've attached my original description of my changes.

Ellen


FUNCTIONALITY

A user of mailing list foo creates a new thread with a base name of bar by 
sending email to foo-new-bar@host.  The system appends an integer to bar to 
generate a unique thread name, e.g., bar1.  All subscribers to mailing list 
foo receive the first message of any thread.  The message headers are:
         To: foo-bar1@host
         From: original-sender@wherever
If a user chooses reply, the new message goes to the original sender 
(assuming a decent MUA).  It a user chooses reply-all, the new message 
becomes part of the thread bar1.

When subscribing (or subsequently), each user specifies whether they want 
to be subscribed to new threads by default.  If so, the user gets all 
messages in a new thread (unless they explicitly unsubscribe).  If a user 
chooses NOT to be subscribed to new threads by default, they only get the 
initial message unless they explicitly subscribe.  Each message contains 
(un)subscribe information both as a URL and mailto to make the operations 
as lightweight as possible; e.g.,

         To unsubscribe from this conversation, send email to 
foo-bar1-unsubscribe@javamlm.mills.edu
         or visit 
http://javamlm.mills.edu/scripts/override?listname=foo&conversation=14&preference=0.
         To unsubscribe from foo, send email to 
foo-unsubscribe@javamlm.mills.edu.

Note that thread membership is determined solely by the address to which a 
message is sent, not the message's subject, references, or other headers.

IMPLEMENTATION

We implemented threads by including a threadID in each message's metadata, 
which was stored in a relational database, as was information about each 
thread, subscription, etc.  The following SQL query determines to whom to 
send a message in thread 37:

SELECT email
FROM Subscriber
WHERE deleted = FALSE AND
((Subscriber.preference = 1 AND
   NOT EXISTS
    (SELECT * FROM Override
     WHERE Override.subscriber_id = Subscriber.subscriber_id
     AND Override.thread_id = 37
     AND Override.preference = 0))
  OR
  (Subscriber.preference = 0 AND
   EXISTS
    (SELECT * FROM Override
     WHERE Override.subscriber_id = Subscriber.subscriber_id
     AND Override.thread_id = 37
     AND Override.preference = 1)))

The full schema is in the paper.  I'm including the query here to give you 
an idea of the complexity and to show that list membership is calculated on 
the fly.