perform_action

# File actionpack/lib/action_controller/base.rb, line 851
      def perform_action
        if self.class.action_methods.include?(action_name) || self.class.action_methods.include?('method_missing')
          send(action_name)
          render unless performed?
        elsif template_exists? && template_public?
          render
        else
          raise UnknownAction, "No action responded to #{action_name}", caller
        end
      end