Voting system extracted a library

answer.rb

class Answer < ActiveRecord::Base
  include Votes


  act_as_votes
end

question.rb

class Question < ActiveRecord::Base
  include Votes

  act_as_votes
end

vote.rb

class Vote < ActiveRecord::Base
  attr_accessible :tendency, :votable_id, :votable_type

  belongs_to :voteable, :polymorphic => true, :counter_cache => true
end

votes.rb

module Votes
  def self.included(base)
    base.extend(ClassMethods)
  end

  module ClassMethods

    def act_as_votes
      has_many :votes, :as => :voteable, :dependent => :destroy
    end

    def most_voted
      order('votes_count desc')
    end

  end

  def vote_up
    votes.create(tendency: 1)
  end

  def vote_down
    votes.create(tendency: -1)
  end
end