Adding reCAPTCHA to Movable Type
UPDATE 2007.07.11: version 1.2 released.
UPDATE 2007.08.29: instructions for MT 4.0.
UPDATE 2008.05.01: instructions for MT 4.1.
Joel just clued me in on a new Captcha system called reCAPTCHA. What's different about reCAPTCHA is that they use the verification words to correct OCR mistakes in scanned books. In their words: "About 60 million CAPTCHAs are solved by humans around the world every day.... in aggregate these little puzzles consume more than 150,000 hours of work each day. What if we could make positive use of this human effort?"
They provide PHP code and a WordPress plugin, but I'm using Movable Type here, so I wrote a Movable Type plugin to use this system. Details follow...
Installing in Movable Type
I've tested this plugin with Movable Type 3.2. It should work with 3.3 also. NOTE: skip to the bottom for Movable Type 4.x.
- Download the reCAPTCHA plugin: Recaptcha.zip
- Copy the
Recaptcha.plfile to yourmt/pluginsdirectory. - Edit your
mt/lib/MT/App/Comments.pmfile, somewhere around line 230, adding the block below noted with "begin addition":
# Run all the Comment-throttling callbacks
my $passed_filter = MT->run_callbacks('CommentThrottleFilter',
$app, $entry);
$passed_filter ||
return $app->handle_error($app->translate("_THROTTLED_COMMENT"),
"403 Throttled");
### BEGIN ADDITION FOR RECAPTCHA PLUGIN ###
my $error_message = MT->run_callbacks('CommentErrorFilter', $app, $entry);
if ($error_message) {
return $app->handle_error($error_message);
}
### END ADDITION FOR RECAPTCHA PLUGIN ###
- Edit your templates for comments and comment preview to include something like:
<p>
Verification (needed to reduce spam):
<$MTRecaptchaBox$>
</p>
- Go into the Movable Type admin interface, click "Settings" (left bar), then "Plugins" (across the top). You should see "reCAPTCHA" listed with your plugins. Click "Show Settings" and enter the public and private keys you got from recaptcha.net when you signed up. Click "Save Changes."
- You should now rebuild your site so the reCAPTCHA box will show up on your pages. Click "Rebuild Site" (left bar).
Notes for Version 1.2 Upgrade
If you are upgrading from a version prior to 1.2, you'll notice the public/private keys have moved out of the Recaptcha.pl source file and into the MT settings page, where they belong. Also, the change to Comments.pm is different. Please replace the change with the new text shown above.
Notes on the Plugin
The plugin adds two features: the MTRecaptchaBox tag and a callback hook for comment posting. The tag simply generates the correct HTML for displaying a Recaptcha box.
The comment posting hook contacts recaptcha.net to validate the contents of the Recaptcha box. Unfortunately, I couldn't properly implement this without changing Comments.pm; I needed to add a new callback which would allow a plugin to cause comment submission failure and return an error message to the user. The existing mechanisms (throttling, junk, and 'CommentFilter') weren't good enough. I did this the nicest way possible, though, by adding another callback hook.
Movable Type 4.0
MT 4.0 has a new CAPTCHA plugin API, and they supply a reCAPTCHA plugin. Unfortunately, it's busted. Here's how to make it work:
- Copy the reCaptcha folder from extras/examples/plugins to your plugins directory.
- Edit the reCaptcha.pl file: change
system_config_templatetoconfig_templateat line 20. - Also in reCaptcha.pl at line 29, add your keys like so:
['recaptcha_publickey', { Default => 'YOUR-PUBLIC-KEY-HERE' }],
['recaptcha_privatekey', { Default => 'YOUR-PRIVATE-KEY-HERE' }],
- Now go to the Movable Type dashboard in your browser, Preferences > Blog Settings > Comments. Set "Immediately Approve Comments From" to "anyone." Near the bottom is a chooser called "CAPTCHA provider." Select reCAPTCHA and click Save Changes.
- In the sidebar select Registration. Check the "Anonymous Comments" checkbox and deselect the rest, click Save Changes.
- Rebuild your site.
Something is busted with the Preferences > Plugins panel (it won't save the keys if you enter them there) so that's why you need to hard-code them in reCaptcha.pl. I've submitted a bug to SixApart so hopefully these problems will be fixed in the next release of MT 4.
Movable Type 4.1
SixApart has fixed the reCATCHA plugin in 4.1. Here's what you need to do:
- Copy the mt/extras/examples/plugins/reCaptcha directory to mt/plugins/reCaptcha.
- Edit the comment form template as indicated in the README file. Ignore the part about the JavaScript index template.
- Go to Preferences > Blog Settings > Comment and set "CAPTCHA Provider" to reCAPTCHA. Save your changes.
- Go to Preferences > Plugin Settings > reCaptcha > Settings and fill in the public and private keys. Save changes.
- Rebuild your site.
Update 2008.05.02: Marcos Lara adds: if you've turned on Movable Type's built-in spam protection, turn that back down to zero when using reCAPTCHA. Otherwise all comments will get marked as needing moderator approval.
Thanks
Many thanks to Ian Peters for getting the plugin integrated with the MT settings page, and other tasty improvements.
Comments
I'm giving the recaptcha plugin a try here. The first word is easy to read, but the second one, which must be the OCR error... Well, let's just say that it's obvious why this OCR attempt failed. I'm giving it my best guess. (The one that it's giving me here on the preview is a lot better.)
Posted by: Joel Odom | May 30, 2007 6:00 AM
I'm just trying out a few more captchas. Ignore this comment... (Ah, here's one with an n with a tilde. I don't know how to type that on this keyboard.)
Posted by: Joel Odom | May 30, 2007 6:06 AM
Josh, thanks so much for creating this. I've installed it and it works really well, which is something of a first for Movable Type captcha software in my limited experience.
Posted by: Mark | May 30, 2007 3:16 PM
I can't get past your Captcha step whether I type the 2 words with one space between them or two spaces.Help!
Posted by: Jim Schatz | June 1, 2007 11:22 AM
Just curious if it ignores a space between the words
Posted by: Anonymous | June 7, 2007 3:08 AM
Thanks for doing this! I've always manually moderated comments but I hate the way it stops any sort of conversation happening. Will be installing this very soon.
Posted by: Sarah | June 16, 2007 6:32 PM
I installed the plug-in but the test consistently fails.
Posted by: Sylvia Tognetti | June 18, 2007 5:14 PM
hi.. I'm Jaanus, just testing your system and considering to use on my own MovableType installation.
Posted by: Jaanus | June 19, 2007 5:13 AM
Sylvia, In the Recaptcha.pl file there's two lines that say 'YOUR_PUBLIC_KEY_HERE' and 'YOUR_PRIVATE_KEY_HERE'; did you set those with the info recaptcha.net gave you? If so, can you copy-n-paste the error message you're seeing into an email?
Posted by: Josh Carter | June 19, 2007 7:32 AM
I finally got it to work - after a bit of trial and error with placement of the template code. Since they were test comments on a test post, I deleted all of it. THANK YOU very much for your assistance - and for whatever work you did on the plug-in.
Posted by: Sylvia Tognetti | June 19, 2007 7:34 AM
Hi Josh, this works awesome from the first comment post, but all comments attempted from the COMMENT PREVIEW page fail the Captcha test on my blog. Any ideas?
Posted by: Ella Speed | July 7, 2007 2:53 PM
I'm also unable to get the plugin working from the preview page. Anyone had any luck with this?
Posted by: Ian Peters | July 10, 2007 10:38 AM
It's working from the preview page here. Can you give me more detail on the version of MT you have installed? Also, send me your mt/lib/MT/App/Comments.pm file so I can double-check the changes there.
Posted by: Josh Carter | July 10, 2007 10:45 AM
Sorry about that. Turned out to be a misconfiguration in the MTKeystrokes plugin that had been installed. Preview's working just fine.
Posted by: Ian Peters | July 11, 2007 1:06 PM
HI, I am trying to get the reCaptcha plug in to work on version 3.2 - I have the plug in installed, and keysin place, I see the reCaptcha box - but it doesn't seem to work. I can type anything in the box and it doesn't authenticate - doesn't fail the post. Any ideas?
Posted by: JD Shipengrover | August 1, 2007 7:14 AM
I tried installing your plugin on the MT4 version to no avail. MT4 ships with an example reCaptcha plugin that didn't seem to work either, but by using the two plugins in conjunction I have got this to work (finally after two days pulling my hair out). It doesn't require any fiddling with the comments.pm file, and I had to manually enter the keys into the Recapture.pl file. Also had to remove the id from the div where the code goes in the comment form template. But now it works and I couldn't be happier.
Posted by: Toni | August 11, 2007 9:40 PM
Do you think this will work with Movable Type version 2.65?
I'll try it out if you think it might.
Posted by: Emmanuel Huna | August 25, 2007 7:18 PM
Emmanuel: I have no idea what the plugin system for MT 2.65 looks like. If I had to guess, this plugin wouldn't work without a fair bit of modification.
Posted by: Josh Carter | August 27, 2007 9:45 AM
Ok I followed the above directions but I do not get the "Show Settings" button in the plugin manager. Plugin is enabled, I tried playing with the permissions on the .pl to no avail. MT version 3.32
Posted by: KMS2 | August 27, 2007 1:24 PM
Josh,
I am trying to install on MT4 and all I have are the cryptic hints that Toni mentioned above.
Could you please explain to me how to install this on MT4? I am willing to do any kind of Perl script configuration as long as it's clearly explained, since I am not a programmer.
Much appreciated,
Jonathan
Posted by: Jonathan | August 28, 2007 4:04 PM
Thanks for the questions about MT 4. I just posted instructions above for making this work.
Posted by: Josh Carter | August 29, 2007 7:33 AM
FYI, in MT 4.0, the public/private keys are actually being saved, they're just not being displayed in the settings form. You can fix that by setting the config_template to the following:
This way you can avoid hardcoding the reCaptcha public/private keys.
Posted by: stepan | August 30, 2007 5:45 AM
Stepan: I tried that, but the keys it was saving didn't actually match what was going into the template form. I put one set of data into the default settings, and another set into the config fields, then rebuilt the site. The reCaptcha code on the generated web page used the default settings -- not what the config fields displayed!
Posted by: Josh Carter | August 30, 2007 7:41 AM
Thanks very much for your work, but I have a question after all.
I tried to install reCaptcha on MT4, but failed. Your guide is good, but for people with a bit of knowledge in programming.
My steps were:
1) I transfered reCaptcha directory from examples/plugins to plugins. So this ok
2) I have moderated line 20, and shortened it, by deleting 'system_'
3) At line 29 I have substituted two lines with the ones given by you. Of course I entered my public and private keys there. You call it hardcore edition or whatever. English is not my native language.
4)I have chosen Captcha provider and rebuilt the site. And nothing happens. Would please be so kind to explain step by step what to next.
Posted by: R | September 5, 2007 8:08 AM
is it possible to place a racaptcha box in every form that we use is the pages of the blog o site other than comments form? if so, how we can do that?
Posted by: frh | September 8, 2007 5:16 AM
Thanks for this guide. I'm using MT4, and found ut's especially important to change the template so that the public and private keys get stored. Otherwise the reCAPTCHA box just doesn't appear (no error messages either!)
Posted by: Nik Roberts | November 11, 2007 5:29 AM
Just seeing if this works - thinking of using it.
Posted by: Anthony | November 15, 2007 2:22 AM
cool
Posted by: tester | November 17, 2007 7:06 AM
testing recaptcha
Posted by: tester | November 17, 2007 7:40 AM
cheat
Posted by: Anonymous | November 17, 2007 8:33 AM
test
Posted by: Senthilkumar | November 17, 2007 11:08 AM
Why my recaptcha filed always fails text verification?
Posted by: Anonymous | November 22, 2007 2:58 AM
Excellent plugin! It looks and it works like a charm
Posted by: Mihai Bocsaru | December 2, 2007 12:25 PM
Has anyone got this working on MT 3.31? I have installed and it is showing up, but not authenticating.
Get the following error:
Your comment submission failed for the following reasons:
Failed CAPTCHA verification; please use your browser's back button and re-enter the verification words. Error: challenge field cannot be empty.
Posted by: Deb | December 8, 2007 12:32 AM
are all verifications running very slow right now?
Posted by: john | December 31, 2007 2:15 AM
Wonderful, many thanks
Posted by: Stroyka | January 13, 2008 10:33 AM
Would it be difficult to modify your plugin for MT 3.14 (I am missing JunkFilter.pm to start with)
Posted by: David Kaspar | January 30, 2008 5:03 AM
Just for everyones info, in 4.1 the plugin seems to work out of the box, just copy it, go to plugin settings for your blog and enter your keys there. Activate in blog settings.
Posted by: minime | March 3, 2008 8:19 PM
Just for everyones info, in 4.1 the plugin seems to work out of the box, just copy it, go to plugin settings for your blog and enter your keys there. Activate in blog settings.
Posted by: minime | March 3, 2008 8:20 PM
trying without space
Posted by: Anonymous | March 25, 2008 11:18 AM
I would very much like to use this. I just upgraded to mt 4.0, but I don't see the recaptcha plug in on my plug in page. All the plugins that show are Multi Blog 2.0, Spam Lookup - Lookups 2.11, Spam Lookup Link 2.11, and Spam Lookup Keyword Filter 2.1. My husband helped me set up the captcha he is using, but I don't like it and my readers are having problems with it. I would like to do the reCaptcha, but am not sure where to start. Any help would be appreciated! TIA!
Posted by: Melissa Markham | March 29, 2008 6:10 AM
Okay, I know I sent you a comment, but I figured out my previous question. There is now a plug in avaialable. I downloaded it and followed the instructions in the read me file. But the recaptcha is still now showing up.
The final step I am told to do is remove this from my javascript index template, but it is not there in that template. It also says I can remove from my Global Java Script, but I don't see that template. :
captcha_timer = setInterval('delayShowCaptcha()', 1000);
Any information you can share with me would be greatly appreciated! TIA!
Posted by: Melissa Markham | March 29, 2008 7:35 AM
these instructions broke my anonymous comments completely.
the result of following this was my MT4.1 w/pro pack always returned "awaiting moderator approval" after the recaptcha approval completed successfully, despite the fact the moderator never received a single request or notification of the pending request and despite the fact that anonymous comments are allowed.
is there any help?
Posted by: rubyvrooom | April 29, 2008 6:15 PM
Hi. Hope someone can help. I installed this plugin with MT 3.2. Everything seemed to work fine except I can't get the actual reCAPTCHA box to display. Can you help.
Posted by: James | April 30, 2008 6:56 PM
Ok, one more problem, I tried unchecking the box in the reCAPTCHA settings that says, 'Enable reCAPTCHA filtering for this blog.' But now comments don't work at all for my site. The error message I get is '1.' Any help would really be appreciated.
Posted by: James | May 1, 2008 12:46 AM