protect_from_forgery (ActionController::RequestForgeryProtection::ClassMethods)

    # File lib/action_controller/request_forgery_protection.rb, line 67
          def protect_from_forgery(options = {})
            self.request_forgery_protection_token ||= :authenticity_token
            before_filter :verify_authenticity_token, :only => options.delete(:only), :except => options.delete(:except)
            if options[:secret] || options[:digest]
              ActiveSupport::Deprecation.warn("protect_from_forgery only takes :only and :except options now. :digest and :secret have no effect", caller)
            end
          end