Add Ownership to Rails 3 App

gistfile1.rb

module Ownership
  
  module Model
    
    def self.included(base)
      base.instance_eval do 
        before_save :set_creator_and_updater
        belongs_to :creator, :class_name => 'User', :foreign_key => 'creator_id'
        belongs_to :updater, :class_name => 'User', :foreign_key => 'updater_id'    
        validates_presence_of :creator, :updater
        attr_accessible :current_user
      end
    end

    def current_user=(id) 
      @current_user = User.find(id) 
    end
    
    def current_user()    
      @current_user                 
    end
  
    private
  
    def set_creator_and_updater
      if self.creator_id.nil? then
        self.creator_id = @current_user.id
        self.updater_id = @current_user.id
      else
        self.updater_id = @current_user.id
      end
    end

  end
  
  module Controller

    def self.included(base)
      base.class_eval do
        
        before_filter :add_ownership_to_params
        
        def add_ownership_to_params
          model_key = self.class.to_s.gsub(/sController/, '').underscore.to_sym
          if params[model_key].present? && current_user
            params[model_key][:current_user] = current_user.id.to_s
          end
        end

      end
    end

  end
  
end