require_logged_user.rb

module RequireLoggedUser
  protected
  def require_logged_user!
    before_filter do
    return true if current_user.present?
    # if the method hasn't returned, there is no user logged in!
    # flash a warning and redirect the user to the log in page
    flash[:warning] = "You must log in before proceeding!"
    redirect_to new_user_session_path and return
  end

  def self.extend_object(controller)
    super
    controller.send(:require_logged_user!)
  end

end 

store_checkouts_countroller.rb

class StoreCheckoutsController < ApplicationController
extend RequireLoggedUser

...

end