Wiki-Spammers (was: [Pmwiki-users] pmwiki.org - version 1 - vandalised)

[Thomas -Balu- Walter]

At around 04:00 this morning I noticed that "bob" once again vandalized
my Wikis (old and new one), so I undid his changes... I also locked the
old wiki pages by giving an edit password.

About 20 Minutes later the following happened:

 * Main.HomePage . . . 2005-01-10 04:23 by bob
 * Main.HomePage . . . 2005-01-10 04:27 by bob
 * Main.HomePage . . . 2005-01-10 04:28 by bob
 * Main.WikiSandbox . . . 2005-01-10 04:33 by bob
 * Main.WikiSandbox . . . 2005-01-10 04:37 by bob
 * Main.WikiSandbox . . . 2005-01-10 04:38 by bob
 * Main.SideBar . . . 2005-01-10 04:44 by bob
 * Main.SideBar . . . 2005-01-10 04:48 by bob
 * Main.SideBar . . . 2005-01-10 04:48 by bob
 * Main.SearchWiki . . . 2005-01-10 04:53 by bob
 * Main.SearchWiki . . . 2005-01-10 04:57 by bob
 * Main.SearchWiki . . . 2005-01-10 04:58 by bob
 * PmWiki.WikiHelp . . . 2005-01-10 05:02 by bob
 * PmWiki.WikiHelp . . . 2005-01-10 05:06 by bob
 * PmWiki.WikiHelp . . . 2005-01-10 05:07 by bob
 * PmWiki.EditQuickReference . . . 2005-01-10 05:11 by bob
 * PmWiki.EditQuickReference . . . 2005-01-10 05:16 by bob
 * PmWiki.EditQuickReference . . . 2005-01-10 05:16 by bob
 * Main.RecentChanges . . . 2005-01-10 05:21 by bob
 * Main.RecentChanges . . . 2005-01-10 05:37 by bob
 ...

The pages were not changed though as I guess PmWiki ignored them because
of a missing password.

I do not want to block all visitors from modifying pages or having to
approve their links.

Even worse I think "bob" does not care if his links are just plain text
and not linked. "does not care" as in "change the pages anyway and don't
figure out that the links don't have any effect on his page ranking or
whatever he tries to do". So he will keep vandalising the pages.

So I wonder if another mechanism would be to disallow adding of content
with more than X external links in it.
Probably not - because the spammers than will just split their adding of
new links into more tha n one edcit request probably.

Another idea: having the visitors to enter a code that is randomly
generated inside a graphic if they add content with more than x external
links?

I am a little low on time at the moment, but I'd probably go for
something like the last if someone tells me an easy way to count the
external links (not enough time to figure out the needed regexes :).

     Balu