RobotCatcher

RobotCatcher makes your forms smarter and keeps bots away.

Prerequisites:

• Ruby 1.9.3 or above (built with for example rbenv and ruby-build)
• Bundle
• A Rails application (Rails 3.2.22)

Installation is simple! Add this line to your application's Gemfile:

gem 'robot_catcher'

Or in your gem specification (gemspec) file:

Gem::Specification.new do |s|
    ...
    s.add_dependency 'robot_catcher'

After running bundle install, RobotCatcher's functionality will be available in your project.

NB: Remember to require 'robot_catcher manually in case RobotCatcher is a depedency of your engine, or require it in the library file of your engine.

RobotCatcher is a small form plugin that uses several kinds of hashing to consider whether a form has been filled out by a bot or a human being.

In any forms in your Rails application. Instead of form_for, use rc_form_for, and specify the request ip address as an argument (typically request.remote_ip:

rc_form_for(@article, ip: request.remote_ip) do |f|
    f.label 'title'
    f.text_field 'title'

    f.label 'text'
    f.text_area 'text'

    f.submit
end

Idem dito in case you want to use form_tag or anyother field *_tag:

rc_form_tag('/articles', ip: request.remote_ip) do
    label_tag 'title'
    rc_text_field_tag 'title'

    label_tag 'text'
    rc_text_area_tag 'text'

    submit_tag
end

NB: In case of tags, only use tags helper methods on fields (i.e. not on labels or submit).

In special cases, especially when mixing html and erb, you might want to generate a hash input manually. Important: the label in rc_hash_tag should correspond to the name attribute's value in the following input tag:

<%= rc_form_tag('/articles', ip: request.remote_ip) do %>
    <label for="title">Title</label>
    <%= rc_hash_tag 'title' %>
    <input id="title" type="text" name="title"></input>
    
    ...
<% end %>

To specify the attributes that should be investigated by the robot catcher, use the class method robot_catch. See the example below. A prerequisite is that the model class is a child of ActiveRecord::Base.

class Article < ActiveRecord::Base
	robot_catch :title, :text
    ...
end

In the current version, catching robots is done by using the robot? method on a model object. The arguments are the original params hash (technically a ActionController::Parameters instance), and the request ip address. It be the original params hash because that hash contains the information (i.e. spinner, timestamp, etc.) that the robot catcher checks. See the example below.

def create
    @article = Article.new(params[:article])

    if @article.robot?(params, request.remote_ip)
        redirect_to @article, notice: 'Stupid robot.'
        return
    end

    if @article.save
        redirect_to @article, notice: 'Article was successfully created.'
    else
        render :new
    end
end

NB: This requires some knowledge about the difference between what rc_form_for and rc_form_tag generates. As for in the example given in the front-end section with rc_form_tag, the params hash will include no :article key, so a new article object is made by passing in the raw params hash (since this contains the right attribute keys and values). Anyway, if you want to do it the Rails way, use rc_form_for like in the example above.

• Store robot catches in database
• Configuration (e.g. for a secret that is used for hashing)
• Better usage of concerns
• More DRY

• Random order on spinner hasher
• Support for more tags
• Integration into native validations
• Rewriting native form helper class

This project uses MIT-LICENSE.