Spam on Trac

[Andrew Whitworth]

As an emergency measure I've disabled TICKET_CREATE and TICKET_APPEND
permissions on trac for authenticated users. This is an attempt to
control the levels of spam we've been getting on trac.

A big problem with the trac spam is that we have so much
infrastructure to broadcast it: Trac has an RSS feed for tickets which
several people are subscribed to. dalek reports new tickets to IRC,
and from there it is included in the IRC logs.

I think it's pretty much unacceptable to be rebroadcasting spam like
this, especially when we have so many new people (GSoC students and
related people) coming to our project for the first time.

We need to find a real anti-spam solution for Trac (which may involve
upgrading our Trac instance to a newer version). Once we get some kind
of solution in place we can re-add these permissions. In the interim,
people who want to report issues are going to need special permission.
It sucks but hopefully this is a short-term problem.

--Andrew Whitworth