CAPTCHA validation

This plugin adds the ability to require CAPTCHA validation in your model. It depends on RMagick to generate images.

Right now there are two different challenges in this plugin. There’s the familiar, but inaccessible image with embedded text, and then there’s another type of challenge which involves asking the user a (simple) question to prove he is not a robot. The latter type is also passable by people with vision impairments, and as a bonus it is also more lightweight.

Usage

How to use in your Rails application.

Install

Put this plugin in your application’s vendor/plugins directory. This can be done easily using the script/plugin script in your application:

  script/plugin install http://nimrod.interinter.net/plugins/trunk/validates_captcha

If your app is in Subversion you may want to include an -x to associate the plugin with its original repository so you can svn up it later. Also, <strong>note the changed address for the repository</strong> if you have previously used this plugin.

Prepare

This plugin assumes it has write access to a directory where a PStore file with the generated CAPTCHA challenges is stored. This is by default var/data. You can create this directory by running script/generate captcha store_directory in your application’s root folder. You should check that your web server’s user has write access to this directory.

If you plan to use the image challenges, these will also need to be stored in a server-writable directory. This is by default public/images/captcha. You can create this directory by running script/generate captcha image_directory in your application’s root directory.

Both of these locations can be changed. See FleskPlugins::CaptchaConfig for details.

Update Model

This step is not necessary if you want to validate the challenge in your controller. Instructions on how to do that are further down on the page.

  class MySuperModel < ActiveRecord::Base
    validates_captcha
  end

Update View

In your view, put this inside the form for the model that requires CAPTCHA validation:

  <% c = prepare_captcha :type => :image -%>
  <%= captcha_hidden_field c, 'my_super_model' %>
  <%= captcha_image_tag c %>
  <%= captcha_label 'my_super_model', 'Type in the text from the image above' %>
  <%= captcha_text_field 'my_super_model' %>

To use the question challenge instead, do this:

  <% c = prepare_captcha :type => :question -%>
  <%= captcha_hidden_field c, 'my_super_model' %>
  <%= captcha_question_as_label c, 'my_super_model' %>
  <%= captcha_text_field 'my_super_model' %>

See FleskPlugins::Captcha::Helpers for how to customise your view.

Update Controller

If you want to validate the challenge in your controller, you can use the +captcha_valid?+ method:

  def save
        supermodel = MySuperModel.find(params[:id])
        supermodel.attributes = params[:my_super_model]

        if captcha_valid?(params[:my_super_model][:captcha_id], params[:my_super_model][:captcha_validation])
                supermodel.save
        else
          flash[:error] = "Are you sure you're human?"
          redirect_or_something
        end
  end

If you want to let the model handle the validation, you need to assign the values from your form to your model. If you’re using some form of mass-assignment, this will happen automatically:

  def save
    @supermodel = MySuperModel.find(params[:id])
    @supermodel.attributes = params[:my_super_model]
    @supermodel.save
  end

The virtual attributes, captcha_id and captcha_validation, are accessible to mass-assignment. If you’re assigning each attribute seperately, you will also have to assign these virtual attributes:

  def save
    @supermodel = MySuperModel.find(params[:id])
    @supermodel.name = params[:my_super_model][:name]
    @supermodel.description params[:my_super_model][:description]
    @supermodel.captcha_id = params[:my_super_model][:captcha_id]
    @supermodel.captcha_validation = params[:my_super_model][:captcha_validation]
  end

Restart server

For Rails to use the newly installed plugin, you have to restart the server, even in development mode. You only have to do this once.

Contact

You can contact me at toredarell att gmail doot com

Contributors

Serge Sozonoff
Blake Watters
Manik Juneja
Joscha Diehl
Mark Lussier
Bradford Folkens

Licence

See MIT-LICENCE (same as Rails; use however you want; if your computer explodes it’s not my fault)

README