plataforma_registrations_controller.rb

class PlataformaRegistrationsController < DeviseController
  prepend_before_filter :require_no_authentication, :only => [ :new, :create, :cancel ]
  prepend_before_filter :authenticate_scope!, :only => [:edit, :update, :destroy]

  # GET /resource/sign_up
  def new
    resource = build_resource({})
    app_id = session[:user_return_to].match(/client_id=(\w+)/)[1]
    application = Doorkeeper::Application.where(:uid => app_id).first
    respond_with resource, :layout => application.name
  end