Doorkepper and CanCan

gistfile1.rb

# routes
use_doorkeeper do
     controllers :applications => 'custom_applications',
                 :authorized_applications => 'custom_authorized_applications',
                 :authorizations => 'custom_authorizations'
end

# application
config.to_prepare do
      # Only Applications list
      Doorkeeper::ApplicationsController.layout "application"
      # Only Authorization endpoint
      Doorkeeper::AuthorizationsController.layout "application"
      # Only Authorized Applications
      Doorkeeper::AuthorizedApplicationsController.layout "application"
end

class CustomAuthorizationsController < Doorkeeper::AuthorizationsController
  include BeforeAction

  before_action :foo, :bar
end

class CustomAuthorizedApplicationsController < Doorkeeper::AuthorizedApplicationsController
  include BeforeAction

  # only users signed in with Devise can see authorized apps
  before_action :authenticate_user!, :foo, :bar

  # CanCan, the below line generate error, I cant use CanCan?!
  # authorize_resource 
end

class CustomApplicationsController < Doorkeeper::ApplicationsController
  include BeforeAction

  # CanCan, the below line generate error, I cant use CanCan?!
  #authorize_resource

  before_action :authenticate_user!, :foo, :bar
end