Erro未初始化的常量Devise :: OmniAuthCallbacksController

Question

在rails 4下的devise中实现OmniAuth时出现以下错误：

uninitialized constant Devise::OmniAuthCallbacksController
app/controllers/usuarios/omniauth_callbacks_controller.rb:1:in `<top (required)>'

就像我无法扩展Devise :: OmniAuthCallbacksController

我的档案是：

class Usuarios::OmniauthCallbacksController < Devise::OmniAuthCallbacksController
   def all
  end
  alias_method :office365, :all 
end

我的宝石

宝石＆＃39;设计＆＃39; gem＆＃39; omniauth＆＃39; gem＆＃39; omniauth-office365＆＃39;

用户模型

class Usuario < ActiveRecord::Base
  devise :database_authenticatable, :registerable,:recoverable, :rememberable, :trackable, :validatable, :omniauthable, 
  :omniauth_providers => [:outlook365]

end

感谢。