calculate_average_worker.rb

class CalculateAverageWorker
  @queue = :default
  
  def self.perform(rating_id)
    rating = Rating.find(rating_id)
    total  = Rating.where(rabbit_id: rating.rabbit_id).count
    sum    = Rating.where(rabbit_id: rating.rabbit_id').sum(:value)
    
    profile = RabbitProfile.find_by(user_id: rating.rabbit_id)
    profile.ratings_total  = total
    profile.rating_average = sum.to_f / (5*total.to_f)
    profile.save!
  end
end

rating.rb

class Rating < ActiveRecord::Base
  after_commit :enqueue_worker
  
  def enqueue_worker
    Resque.enqueue(CalculateAverageWorker, self.id)
  end
end