Wikimedia Bugzilla is closed!

[I've gone ahead and CC'd some folks who appear to have been interested in this
topic when it has come up in the past. If you have no interest/possess an active
disgust for this feature, I appologize for the spam.]

The topic of supporting RSS feeds for user watchlists is one that has come up
many times on mediawiki.org and the mailinglists. This feature has become a
personal itch for me lately, so I've done some investigation of previous efforts
and discussion on this topic. For a wide variety of reasons, these past efforts
have failed. I hope to have corrected many of those concerns here, and ideally,
to have created something that can be accepted into the repository. 

Attached is a patch against CVS to add watchlist RSS feeds. Highlights of the
design are below: 

- Authentication: Users are assigned a special RSS watchlist token when they
first subscribe to their watchlist. Requests for a feed must include both the
user_id and the correct token or they will be denied. Users are warned that
anyone with access to their token may view their watchlist, and are encouraged
not to use this feature if this is a problem for them. Tokens are non-trivial to
guess.

- Server load limiting: Refreshes are limited to once per hour (this can be
configured by the admin as needed). If a user exceeds this limit, the watchlist
will not be generated until the time elapses. This should avoid the dreaded user
who sets their 50,000 page watchlist to reload every 5 minutes. 

- (hopefully) properly localizable and configurable, including a master disable
switch if sites need to disable this feature.

As always, comments and thoughts on the patch are appreciated. If you'd like to
see this in action on a running installation, I have a testing install up at
http://www.zachlipton.com/wikirss (just create an account, add something to
watchlist, and go look at your watchlist). I'm often on as 'zach' on freenode if
you'd like to discuss in realtime. 

Thanks. I hope that we can make this feature work this time around.