[Catalyst] Simple and effective wiki spam prevention

[A. Pagaltzis]

* Christopher H. Laco <claco at chrislaco.com> [2006-04-07 17:00]:
> Trac needs a Captcha plugin.

That is a heavy-handed solution. Wiki gnomes will get rather
irritated by it.

Here are some less intrusive but nonetheless very effective
things which have been effective on the WLUG Wiki:

• Disable anonymous edits. You don’t need to require
  registration, just require that people sign on with a WikiWord
  before they can edit. No password or anything, all that’s
  required is a name. You’d be amazed at how many stupid spambots
  are run off by this.

• Reject edits which insert more than X new external links into
  the page text. I think X=8 at the WLUG Wiki.

• Quarantine new external links with `nofollow`, but strip that
  after another user edits the page. This also means that old
  revisions of the page continue applying `nofollow` to links in
  quickly reverted spam.

• The WLUG Wiki rejects edits which contain chinese characters…

Also, my observation is that sites which have no spam also tend
to attract very little spam, whereas sites with a lot of spam get
spammed a lot. I guess spammers specifically search out the
broken windows because their droppings have the best chances of
surviving at neglected sites.

As you see, you can run a wide-open wiki without any spam problem
if you are a bit creative about your preventive countermeasures
and have a few people watching RecentChanges moderately closely.

Regards,
-- 
Aristotle Pagaltzis // <http://plasmasturm.org/>