Captcha
=======

It is captcha varification plugin for Rails applications. It creates random images and random text written over the 
images and validates the captcha text after the submition of the form.

Installation
============

Captcha installation process.

MiniMagick installation :

    sudo gem install mini_magick

Plugin installation :

    script/plugin install git://github.com/hokam/captcha.git

Uninstallation
==============

    script/plugin remove captcha


Usage
=====

After installation process you need to add 'before_filter' callback in your controller to create captcha image before
the processing of specified actions.

Suppose you have a CommentsController in which you want to create capthca image for "new" action so just add the following
lines in your controller.

class CommentsController << ActionController::Base
  before_filter :create_captcha, :only => [:new]
  # ....
  # ....
end

And for validation of captcha text you need to call validate_captcha funtion in the required action.
Lets say in "create" action of CommentsController you want to apply captcha validation, so do the following addition
in your 'create' action.


class CommentsController << ActionController::Base
  before_filter :create_captcha, :only => [:new]

  def new
    # action related data
  end
  # other action methods

  def create
    if validate_captcha
      # ........
    else
      # ........
    end
  end
end

And add the following line in your html view to create captcha image.

<%= image_captcha_tag %>

If captcha validation failes then captcha plugin set the error message
in flash[:notice] variable, so you should use flash[:notice] variable in
your form for the notification of captcha failure message.

<%= flash[:notice] if flash[:notice] %> 

To read more, use following.

http://rails-plugin-usage.blogspot.com/2011/06/rails-catpcha-plugin-usage.html