SimpleCaptcha is the simplest and a robust captcha plugin. Its implementation requires adding up a single line in views and in controllers/models. SimpleCaptcha is available to be used with Rails 3 or above and also it provides the backward compatibility with previous versions of Rails.
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Zero FileSystem usage(secret code moved to db-store and image storage removed).
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Provides various image styles.
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Provides three level of complexity of images.
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Works absolutely fine in distributed environment(session and db based implementation works fine in distributed environment).
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Implementation is as easy as just writing a single line in your view. “<%= show_simple_captcha %>” within the ‘form’ tags.
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Flexible DOM and CSS handling(There is a separate view partial for rednering SimpleCaptcha DOM elements).
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Automated removal of 1 hour old unmatched simple_captcha data.
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Ruby >= 1.8.7
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Rails >= 3
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ImageMagick should be installed on your machine to use this plugin. visit www.imagemagick.org/script/index.php for more details.
gem "galetahub-simple_captcha", :require => "simple_captcha"
or
gem 'simple_captcha', :git => 'git://github.com/galetahub/simple-captcha.git'
After installation, follow these simple steps to setup the plugin. The setup will depend on the version of rails your application is using.
rails generate simple_captcha rake db:migrate # skip and delete migration if you're using redis or mongoid.
Add the following line in the file “app/controllers/application.rb”
ApplicationController < ActionController::Base include SimpleCaptcha::ControllerHelpers end
In the view file within the form tags add this code
<%= show_simple_captcha %>
and in the controller’s action authenticate it as
if simple_captcha_valid? do this else do that end
In the view file within the form tags write this code
<%= show_simple_captcha(:object=>"user") %>
and in the model class add this code
class User < ActiveRecord::Base apply_simple_captcha end
<%= form_for @user do |form| -%> ... <%= form.simple_captcha :label => "Enter numbers.." %> ... <% end -%>
NOTE: @user.valid? will still work as it should, it will not validate the captcha code.
@user.valid_with_captcha?
NOTE: @user.save will still work as it should, it will not validate the captcha code.
@user.save_with_captcha
SimpleCaptcha detects if your use Formtastic and appends “SimpleCaptcha::CustomFormBuilder”.
<%= form.input :captcha, :as => :simple_captcha %>
Gemfile
gem 'redis' gem 'redis-namespace'
in ‘application.rb’, add belows code under Bundler.require(:default, Rails.env)
SimpleCaptcha.store = 'redis'
create an new initilizer
# config/initializers/captcha.rb redis = Redis.new host: '127.0.0.1', port: 6379 redis = Redis::Namespace.new('express:captcha', redis: redis) SimpleCaptcha.setup do |sc| # Redis instance sc.redis = redis # expire time for redis sc.expire = 3600 # default: 100x28 sc.image_size = '80x34' # default: 5 sc.length = 5 # default: simply_blue # possible values: # 'embosed_silver', # 'simply_red', # 'simply_green', # 'simply_blue', # 'distorted_black', # 'all_black', # 'charcoal_grey', # 'almost_invisible' # 'random' sc.image_style = 'random' # default: low # possible values: 'low', 'medium', 'high', 'random' sc.distortion = 'low' end
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label - provides the custom text b/w the image and the text field, the default is “type the code from the image”
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object - the name of the object of the model class, to implement the model based captcha.
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code_type - return numeric only if set to ‘numeric’
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image_style - provides the specific image style for the captcha image.
There are eight different styles available with the plugin as…
1) simply_blue 2) simply_red 3) simply_green 4) charcoal_grey 5) embosed_silver 6) all_black 7) distorted_black 8) almost_invisible
Default style is ‘simply_blue’. You can also specify ‘random’ to select the random image style.
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distortion - handles the complexity of the image. The :distortion can be set to ‘low’, ‘medium’ or ‘high’. Default is ‘low’.
Create “rails_root/config/initializers/simple_captcha.rb”
SimpleCaptcha.setup do |sc| # default: 100x28 sc.image_size = '120x40' # default: 5 sc.length = 6 # default: simply_blue # possible values: # 'embosed_silver', # 'simply_red', # 'simply_green', # 'simply_blue', # 'distorted_black', # 'all_black', # 'charcoal_grey', # 'almost_invisible' # 'random' sc.image_style = 'simply_green' # default: low # possible values: 'low', 'medium', 'high', 'random' sc.distortion = 'medium' end
You can add your own style:
SimpleCaptcha.setup do |sc| sc.image_style = 'mycaptha' sc.add_image_style('mycaptha', [ "-background '#F4F7F8'", "-fill '#86818B'", "-border 1", "-bordercolor '#E0E2E3'"]) end
You can provide the path where image_magick is installed as well:
SimpleCaptcha.setup do |sc| sc.image_magick_path = '/usr/bin' # you can check this from console by running: which convert end
You can provide the path where should be stored tmp files. It’s usefull when you dont have acces to /tmp (default directory)
SimpleCaptcha.setup do |sc| sc.tmp_path = '/tmp' # or somewhere in project eg. Rails.root.join('tmp/simple_captcha').to_s, make shure directory exists end
You can change the CSS of the SimpleCaptcha DOM elements as per your need in this file.
/app/views/simple_captcha/_simple_captcha.erb
<%= show_simple_captcha %> <%= show_simple_captcha(:label => "human authentication") %>
<%= show_simple_captcha(:object => 'user', :label => "human authentication") %>
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message - provides the custom message on failure of captcha authentication the default is “Secret Code did not match with the Image”
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add_to_base - if set to true, appends the error message to the base.
class User < ActiveRecord::Base apply_simple_captcha end class User < ActiveRecord::Base apply_simple_captcha :message => "The secret Image and code were different", :add_to_base => true end
simple_captcha:
placeholder: "Enter the image value"
label: "Enter the code in the box:"
message:
default: "Secret Code did not match with the Image"
user: "The secret Image and code were different"
Enjoy the simplest captcha implementation.
Author: Sur
Blog: expressica.com
Contact: [email protected]
Plugin Homepage: expressica.com/simple_captcha
Plugin update for rails 3: github.com/galetahub
Any feedback/comment/issue/donation is welcome!