[arch-dev-public] Adding some kind of Captcha to our Wiki

Pierre Schmitz pierre at archlinux.de
Sat May 23 04:13:12 EDT 2009

Hi all,

as discussed here http://bbs.archlinux.org/viewtopic.php?pid=557394 some spam 
bots seem to like our wiki.

I have developed a very simple but effective way to stop such bots. Of course 
they could easily bypass it but as it is not used by anybody else the bot 
programmers just don't know about it.

The idea is to set a cookie on each form which existence will be checked 
before each form action. The cookie is set by an "image" which is included by 
CSS. Until now there seems to be no bot which reads CSS definitions.

Those which use text browsers will see a text form in which they need to enter 
a short hex code in order to submit anything. Anyone else wont even notice 
that there is a captcha.

So, what do you think? Should I activate this plugin? The only thing I need to 
do is translating some error mesages from German into English.

PS: Source code is at: 


Pierre Schmitz

Clemens-August-Straße 76
53115 Bonn

Telefon		0228 9716608
Mobil		0160 95269831
Jabber		pierre at jabber.archlinux.de
WWW		http://www.archlinux.de

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