model add scope

app/models/product.rb

@@ -122,7 +122,7 @@ class Product < ActiveRecord::Base
         end 
             #return ((rate*100).round.to_f/100).to_s + "%"
             # user= "{current_admin_user.email}"
-        return  Session.user_id
+        return  session[:current_user_id]
     end
 
     rails_admin do