Invisible Captcha

Simple spam protection for Rails applications using honeypot strategy and for better user experience. Support for ActiveRecord (and ActiveModel) forms and for non-RESTful resources.

Installation

Add this line to you Gemfile:

gem 'invisible_captcha'

Or install gem:

gem install invisible_captcha

Usage

Model style

View code:

<%= form_for(@topic) do |f| %>

  <!-- You can use form helper -->
  <%= f.invisible_captcha :subtitle %>

  <!-- or view helper -->
  <%= invisible_captcha :topic, :subtitle %>

<% end %>

Model code:

validates :subtitle, :invisible_captcha => true

Controller style

View code:

<%= form_tag(search_path) do %>

  <%= invisible_captcha %>

<% end %>

Controller code:

before_filter :check_invisible_captcha, :only => [:create, :update]

This filter returns a response that has no content (only headers). If you desire a different behaviour, this lib provides a method to check manualy if invisible captcha (fake field) is present:

if invisible_captcha?
  # invalid
else
  # valid
end

If you want to use it in this way but using RESTful forms with form_for, you can call this method with the fake field as a parameters:

if invisible_captcha?(:topic, :subtitle)
  # invalid
else
  # valid
end

Setup

If you want to customize some defaults, add the following to an initializer (config/initializers/invisible_captcha.rb):