Destroy user_attributes and attribute_values when a user is destroyed

app/controllers/panel/users_controller.rb

@@ -65,6 +65,10 @@ class Panel::UsersController < ApplicationController
     else
       @user = User.find(params[:id]) 
       @user.destroy
+      @user.user_attributes.each do |ua|
+        ua.attribute_values.each(&:destroy)
+        ua.destroy
+      end
     end
     
     redirect_to :action => :index

app/models/user.rb

@@ -10,6 +10,7 @@ class User
   field :admin, :type => Boolean, :default => true
   field :active_roles, :type => Array
   
+  has_many :user_attributes
   has_many :user_roles
   has_many :user_infos
   before_save :clean_active_roles