Adding Captcha to your Application

Are you developing an RoR application and want to add CAPTCHA (Completely Automated Public Turing test to tell Computers and Humans Apart) Authentication in it?

*Note
1. simple_captcha plugin is being used here if you want to use other plugin, you can find it in the net.
2. You must have RMagick installed. (This is a prerequisite.)

Here's the simple steps in adding a captcha image:

1. Type this command in your app root dir:
>> ruby script/plugin install svn://rubyforge.org/var/svn/expressica/plugins/simple_captcha


2. After successful installation.

>> rake simple_captcha:setup

(Am using Rails 2.x version for < 2.0 do

>> rake simple_captcha:setup_old)

3. Then do the migration.

>> rake db:migrate

4. Add this line of code to you config/routes.rb

map.simple_captcha '/simple_captcha/:action', :controller => 'simple_captcha'

5. Add this line in the file app/controllers/application.rb

include SimpleCaptcha::ControllerHelpers

6. In your view add:

<%= show_simple_captcha(:object=>"user") %>

7. In your model add:
apply_simple_captcha

8. Validating with captcha:
@user.valid_with_captcha?

9. Saving with captcha:
@user.save_with_captcha

View Options

:label
provides the custom below the image, default is “(type the code from the image)”

:image_style
Provides the specific image style for the captcha image.
There are eight different styles available with the plugin as…

• simply_blue
• simply_red
• simply_green
• embosed_silver
• all_black
• distorted_black
• charcoal_grey
• almost_invisible

Default is ’simply_blye’
You can also specify ‘random’ to select the random image style.

:distortion
Handles the complexity of the image. The :distortion can be set to ‘low’, ‘medium’
or ‘high’. Default is ‘low’.

:code_type
Handles the text of the captcha image. Available options are ‘numeric’ or ‘alphabetic’.
Default is ‘alphabetic’.

:object
the name of the object of the model class, to implement the model based captcha.

How to change the CSS for SimpleCaptcha DOM elements ?
You can change the CSS of the SimpleCaptcha DOM elements as per your need in this file…
For Rails >= 2.0 the partial view file wiil reside as…
“/app/views/simple_captcha/_simple_captcha.erb”
For Rails < 2.0 the partial view file will reside as…
“/app/views/simple_captcha/_simple_captcha.rhtml”

View’s Examples

for detailed info:
http://expressica.com/simple_captcha/

ApplicationController <> NOTE: