Trick Question

A very small and simple CAPTCHA-type spam prevention module. A lightweight, compact and simple alternative to larger and more complex modules such as

• The excellent and very popular Captcha module and the sub module Captcha Riddler
• The intelligent and flexible Mollom module.

Please notice...

CAPTCHA is short for Completely Automated Public Turing-test to tell Computers and Humans Apart, and that is exactly what all these modules do. Perform a test to separate fake submissions from real ones.

Independent

This module is a stand alone module, independent of Captcha and other modules. It contains only one simple questions (riddle) and nothing else. It's not dependent on any other modules, libraries or functions, and does not use graphical elements.
It's flexible and can be used on most forms: node forms as well as user registrations, comment forms and other forms.
It offers you to select one or several forms and to select roles that don't need to be checked, in other words won't see and need to reply to the question.

The idea is to have a really simple question with a very obvious answer. For localized sites you can ask and request replies in your own language for even better bot submission prevention and to almost completely avoid fake submissions from non-local humans, who won't be able to read the questions. You will never be able to completely avoid fake submissions from real humans, though.

Examples

It's recommended to use questions that can be replied to with one letter in order to make the workload on the user as small as possible, but other simple questions and replies will work equally well.
Examples:
"What's the sum of three and four as a digit?" The correct answer is "7"
"What's the first letter in the word salmon?" The correct answer is "s" or "S"
"Tell us Mary Poppins' first name" Correct answer is "mary", "Mary", "MARY" or any combination.
Don't use the above examples, but make your own with similar questions and replies. Since you supply both the question and the correct answer, you are responsible for making it logical and easy to understand.

The module ignores letter case in the reply, and "mary", "Mary", "MARY" and "mARy" will all be correct replies to the last example.

Caveat

Please notice that the Trick Question field is NOT marked as a required field (usually a red asterisk), but that it IS required to be correctly filled out for the form to validate.
This construction is used because Drupal will require you to fill out the trick question to delete a node, which is pretty counter intuitive. This is a core Drupal issue and not an issue for this module only. Any required field needs to be filled out in order for Drupal to accept a deletion.

Configuration

You configure the module on its configuration page in admin > settings > trick_question
Type in a question and the correct answer.
Edit the explanation to tell the users what is happening, and maybe even reveal the correct reply. Since the bots won't be able to read this tip, there's no harm done in giving away the correct answer.
There is no functions to automatically change the question and answer and no function to randomly pick from a list. You yourself will have to go in and change the question and answer now and then if you want a higher level of security.

Now select the forms you want to filter.
You can select any node form as well as the user registration form and the comment submission form. Should you have a form that doesn't appear in the list, simply add the Drupal form ID in the text field below the checkboxes.

You can decide where in your forms you want the Trick Question field to appear by entering a form weight. The default is 50.
50 will usually place it near the bottom of the form, -10 usually in the top.

Save the settings and your question should appear on the relevant forms.

Permissions

Admin is never asked to fill out the Trick Question, so if you want to test this function, you need to be logged in as a user with a role that has to reply.
You might want to go to the permissions page and exclude other user groups (roles) from the test. If you have groups of already tested and trusted people, you may have no need to pester them with the question again. Mark them in the permissions list.
You can at the same time allow certain roles to administer the module and change the question. This privilege should of course only be granted to site administrators, editors, webmasters and similar groups, and never to common users, no matter how trusted they might be.