Idle Time

I’ve finished fixing number 12. Now, when you forget to answer the Turing test, your response will reappear in the comment form when the post loads.

For those of you who run Negative Turing Test on your own blag: WordPress has a bug as of both 2.1 and 2.3. Normally, when you submit a comment, WordPress sets three cookies that it uses to automatically fill in the Name, Email, and URL fields on the commenter’s future visits. When a plug-in like NTT deletes the comment, WordPress fails to notice and empties out the cookies. The result is that, when NTT deletes the comment, the name, email, and URL fields come back empty. (This is true with or without the fix for number 12.)

There’s nothing NTT can do about that—it’s a WordPress bug that I discovered in testing the fix for number 12. I isolated the problem and have already fixed it here, and I’ll soon submit a patch to the WordPress developers so that you can all have this fix as well. Until they accept it, here’s the patch for WordPress 2.3.

Spam comments blocked by Negative Turing Test in June 2007:

38,502

I’ve reset the NTT counter at 26,445 spams. Once again, next month will bring another count of spams-per-month.

I think I’ll do this every month and establish a trend. Maybe find some free graphing software and plot a graph with the counts.

As of r58, you can now tell Negative Turing Test to delete spam comments instead of marking them as spam. (This is in the NTT Options pane.)

I just turned this on here. It worked fine on the test post; we’ll see how well it works in real usage.

Oh, and in case you ever need to delete a comment from a WP plug-in: Use wp_set_comment_status. I thought for so long that WP had no programmatic way to delete comments—now I know that it does.

From time to time, I check a Technorati search for my blog, which I have bookmarked, to see who’s linking to me and what they have to say.

Today I find that chucker has installed NTT. Cool!

chucker: I invite you to email me about you getting spam every few minutes. I’m interested to hear more specifics. My address is on the front page. (Initial hunch: Try turning off Akismet. I gave up on Akismet after all the false positives we had when we tried using it on Adium Trac; as such, I’ve never used it here.)

One of Negative Turing Test’s most recent features is a counter of how many spams it eats. I added this feature last month, and made a note to reveal today what it got up to.

The number of spams blocked by NTT from 2007-02-12 to 2007-03-12 is:

6,220

I should probably get around to making it delete those…

I just committed revision 44 of Negative Turing Test, and am running it now on this blog (and I’ve turned off the Comment Authorization plug-in, which is what used to email you when you commented, prompting you to approve your own comment). It now correctly blocks spam and allows ham; these being the minimum requirements, I call r44 the first working version of NTT. Feel free to try it out on your own blog — or on mine — and report any problems (preferably using the Google Code issue tracker, but email‘s fine too).

I’m not quite done with it. My next step is to add an option for it to outright delete spam instead of simply stamping it “spam” and saving it for some plug-in that I don’t use to study. I’m confident that I will never see a false positive, and if I ever see a false negative, I can simply change the problem that it poses in order to avoid future false negatives.

The plug-in comes with no default challenge: All fields are empty. This means that if you want to block spam with it, you’ll need to think of a challenge to put in there. Please don’t borrow mine, as I put in no default for a reason: If there’s a default (or a really popular challenge), the spammers will pre-program their bots with the correct response and the plug-in will be defeated (and all NTT users who’ve used that challenge will have to change it, and/or will send me a bunch of email). I recommend searching a book of easy jokes or logic riddles.

I’m going to be working on the comment spam problem today. Attempt #1 is adding a Turing test to the comment form; you might not be able to comment while I’m debugging it. I’ll update this post when it’s all working.

UPDATE 2006-12-16: I’ve decided to host the project for attempt #1 at Google Code. It’s called Negative Turing Test. You’ll be able to get the fruits of my labor when it’s done, and you can watch me work on it in the Subversion repo. (And yes, that means that I’m not debugging yet. You can still comment for now. ;)