Ошибка to_sym в запросе ActionController

Question

Я создаю плагин для идентификации запросов мобильных устройств. Любой контроллер, который вызывает is_mobile_aware, должен иметь шаблоны «.html» и «.mobile» для всех действий. Сейчас я просто тестирую свой код. Я пытаюсь получить каждый запрос на использование шаблона «.mobile», но я получаю сообщение об ошибке при выполнении запросов. Вот код с ошибкой ниже:

---

Код:

module ActionController
  module MobileAware
    def self.included(base)
      base.extend(ClassMethods)
    end    

    module ClassMethods
      def is_mobile_aware
        include ActionController::MobileAware::InstanceMethods

        before_filter :set_format
      end
    end

    module InstanceMethods
      def set_format        
        request.format = :mobile          
      end
    end
  end
end

---

Error

неопределенный метод `to_sym 'для nil: NilClass

Запрос

Параметры:

{ "Формат" => "мобильный"}

---

Спасибо за вашу помощь!

---

Полный след:

activesupport (3.0.3) lib/active_support/whiny_nil.rb:48:in `method_missing'
actionpack (3.0.3) lib/action_controller/metal/rendering.rb:10:in `block in process_action'
actionpack (3.0.3) lib/action_controller/metal/rendering.rb:10:in `map'
actionpack (3.0.3) lib/action_controller/metal/rendering.rb:10:in `process_action'
actionpack (3.0.3) lib/abstract_controller/callbacks.rb:18:in `block in process_action'
activesupport (3.0.3) lib/active_support/callbacks.rb:450:in `_run__233835139__process_action__997034143__callbacks'
activesupport (3.0.3) lib/active_support/callbacks.rb:409:in `_run_process_action_callbacks'
activesupport (3.0.3) lib/active_support/callbacks.rb:93:in `run_callbacks'
actionpack (3.0.3) lib/abstract_controller/callbacks.rb:17:in `process_action'
actionpack (3.0.3) lib/action_controller/metal/instrumentation.rb:30:in `block in process_action'
activesupport (3.0.3) lib/active_support/notifications.rb:52:in `block in instrument'
activesupport (3.0.3) lib/active_support/notifications/instrumenter.rb:21:in `instrument'
activesupport (3.0.3) lib/active_support/notifications.rb:52:in `instrument'
actionpack (3.0.3) lib/action_controller/metal/instrumentation.rb:29:in `process_action'
actionpack (3.0.3) lib/action_controller/metal/rescue.rb:17:in `process_action'
actionpack (3.0.3) lib/abstract_controller/base.rb:120:in `process'
actionpack (3.0.3) lib/abstract_controller/rendering.rb:40:in `process'
actionpack (3.0.3) lib/action_controller/metal.rb:138:in `dispatch'
actionpack (3.0.3) lib/action_controller/metal/rack_delegation.rb:14:in `dispatch'
actionpack (3.0.3) lib/action_controller/metal.rb:178:in `block in action'
actionpack (3.0.3) lib/action_dispatch/routing/route_set.rb:62:in `call'
actionpack (3.0.3) lib/action_dispatch/routing/route_set.rb:62:in `dispatch'
actionpack (3.0.3) lib/action_dispatch/routing/route_set.rb:27:in `call'
rack-mount (0.6.13) lib/rack/mount/route_set.rb:148:in `block in call'
rack-mount (0.6.13) lib/rack/mount/code_generation.rb:93:in `block in recognize'
rack-mount (0.6.13) lib/rack/mount/code_generation.rb:75:in `optimized_each'
rack-mount (0.6.13) lib/rack/mount/code_generation.rb:92:in `recognize'
rack-mount (0.6.13) lib/rack/mount/route_set.rb:139:in `call'
actionpack (3.0.3) lib/action_dispatch/routing/route_set.rb:492:in `call'
hoptoad_notifier (2.4.4) lib/hoptoad_notifier/rack.rb:27:in `call'
haml (3.0.25) lib/sass/plugin/rack.rb:41:in `call'
actionpack (3.0.3) lib/action_dispatch/middleware/best_standards_support.rb:17:in `call'
actionpack (3.0.3) lib/action_dispatch/middleware/head.rb:14:in `call'
rack (1.2.1) lib/rack/methodoverride.rb:24:in `call'
actionpack (3.0.3) lib/action_dispatch/middleware/params_parser.rb:21:in `call'
actionpack (3.0.3) lib/action_dispatch/middleware/flash.rb:182:in `call'
actionpack (3.0.3) lib/action_dispatch/middleware/session/abstract_store.rb:149:in `call'
actionpack (3.0.3) lib/action_dispatch/middleware/cookies.rb:295:in `call'
activerecord (3.0.3) lib/active_record/query_cache.rb:32:in `block in call'
activerecord (3.0.3) lib/active_record/connection_adapters/abstract/query_cache.rb:28:in `cache'
activerecord (3.0.3) lib/active_record/query_cache.rb:12:in `cache'
activerecord (3.0.3) lib/active_record/query_cache.rb:31:in `call'
activerecord (3.0.3) lib/active_record/connection_adapters/abstract/connection_pool.rb:353:in `call'
actionpack (3.0.3) lib/action_dispatch/middleware/callbacks.rb:46:in `block in call'
activesupport (3.0.3) lib/active_support/callbacks.rb:415:in `_run_call_callbacks'
actionpack (3.0.3) lib/action_dispatch/middleware/callbacks.rb:44:in `call'
rack (1.2.1) lib/rack/sendfile.rb:107:in `call'
actionpack (3.0.3) lib/action_dispatch/middleware/remote_ip.rb:48:in `call'
actionpack (3.0.3) lib/action_dispatch/middleware/show_exceptions.rb:46:in `call'
railties (3.0.3) lib/rails/rack/logger.rb:13:in `call'
rack (1.2.1) lib/rack/runtime.rb:17:in `call'
activesupport (3.0.3) lib/active_support/cache/strategy/local_cache.rb:72:in `call'
hoptoad_notifier (2.4.4) lib/hoptoad_notifier/user_informer.rb:12:in `call'
rack (1.2.1) lib/rack/lock.rb:11:in `block in call'
:10:in `synchronize'
rack (1.2.1) lib/rack/lock.rb:11:in `call'
actionpack (3.0.3) lib/action_dispatch/middleware/static.rb:30:in `call'
railties (3.0.3) lib/rails/application.rb:168:in `call'
railties (3.0.3) lib/rails/application.rb:77:in `method_missing'
railties (3.0.3) lib/rails/rack/log_tailer.rb:14:in `call'
rack (1.2.1) lib/rack/content_length.rb:13:in `call'
rack (1.2.1) lib/rack/handler/webrick.rb:52:in `service'
C:/Ruby192/lib/ruby/1.9.1/webrick/httpserver.rb:111:in `service'
C:/Ruby192/lib/ruby/1.9.1/webrick/httpserver.rb:70:in `run'
C:/Ruby192/lib/ruby/1.9.1/webrick/server.rb:183:in `block in start_thread'