Refector the include method

lib/rails_api_authentication.rb

 require "rails_api_authentication/version"
+require "rails_api_authentication/configuration"
 require "rails_api_authentication/auth_action"
 require "rails_api_authentication/auth_session"
 require "rails_api_authentication/auth_token"
 require "rails_api_authentication/authable"
+require "rails_api_authentication/acts_as_authenticationable"
+require "rails_api_authentication/acts_as_authentication_handler"
 
 module RailsApiAuthentication
+  extend Configuration
 
+  private
+
+  def self.ensure_models_can_act_as_token_authenticatables model_adapters
+    model_adapters.each do |model_adapter|
+      model_adapter.base_class.send :extend, RailsApiAuthentication::ActsAsAuthenticationable
+    end
+  end
+
+  def self.ensure_controllers_can_act_as_token_authentication_handlers controller_adapters
+    controller_adapters.each do |controller_adapter|
+      controller_adapter.base_class.send :extend, RailsApiAuthentication::ActsAsAuthenticationHandler
+    end
+  end
+
+  available_model_adapters = load_available_adapters RailsApiAuthentication.model_adapters
+  ensure_models_can_act_as_token_authenticatables available_model_adapters
+
+  available_controller_adapters = load_available_adapters RailsApiAuthentication.controller_adapters
+  ensure_controllers_can_act_as_token_authentication_handlers available_controller_adapters
 end

lib/rails_api_authentication/acts_as_authentication_handler.rb

+module RailsApiAuthentication
+  module ActsAsAuthenticationHandler
+    def acts_as_auth_action(klass_sym, options={})
+      include RailsApiAuthentication::AuthAction
+      auth_action klass_sym, options
+    end
+
+    def acts_as_auth_session(klass_sym)
+      include RailsApiAuthentication::AuthSession
+      auth_session klass_sym
+    end
+  end
+end

lib/rails_api_authentication/acts_as_authenticationable.rb

+module RailsApiAuthentication
+  module ActsAsAuthenticationable
+    def acts_as_authentication(params = {})
+      include RailsApiAuthentication::Authable
+      auth_for params
+    end
+  end
+end

lib/rails_api_authentication/configuration.rb

+module RailsApiAuthentication
+  module Configuration
+    mattr_accessor :controller_adapters
+    mattr_accessor :model_adapters
+
+    @@model_adapters = ['active_record', 'mongoid']
+    @@adapters_dependencies = { 'active_record' => 'ActiveRecord::Base',
+                                'mongoid'       => 'Mongoid::Document',
+                                'rails'         => 'ActionController::Base',
+                                'rails_api'     => 'ActionController::API',
+                                'rails_metal'   => 'ActionController::Metal' }
+  end
+end