I have several people subscribing to my lists with plus addressing (i.e. lindsey+mhonarc@ncsa.uiuc.edu (in fact, I'm subscribed to this list in the same way)). This breaks the "Restrict Posting to List Members" option for these accounts...

What I'm trying to do is check for the existence of a '+' in each address in the list of subscribers, and if present, trim it and everything to the right off before checking for a match.

Unfortunately, it appears that FindMatchingAddresses (called from MailList.FindUser) is just passed a dictionary of list members. Implementing the kind of check that I'd like would significantly slow down checking for matches because it couldn't just use the poster's address as a key anymore.

So what's the best way to do this? Do a foreach on each key and check for a match? Like I said, it's slower, but it sure opens up a lot of possibilities. You could then do things like add regular expressions to the list of accepted posters... /.*\.example\.com/ would allow postings from anyone in a given domain (not something I would recommend), /george@example\.(org|com|net)/ would pull three lines together into one, etc. Not terribly useful, but what if you were to incorporate '+' addressing checks through regexes too then? Create a macro like :USER: and :DOMAIN: that would be used in the regex (colons are used since they can't be part of an address according to RFC 822)... Then you would have a regex like

/:USER:\+[^@]*@:DOMAIN:/

:USER: and :DOMAIN: would be derived from the current poster, and each entry within the list of subscribers would be compared against the resulting regular expression (one at a time).

I think that something like the '+' addressing check would be best served internally within Mailman (via a checkbox or whatever), but once the engine is in place it's a lot more extensible.

Comments? I'm willing to mess with this (although I can't guarantee any great speed -- I just started messing with Python a couple of days ago).

Chris