ActiveRecord Global Callbacks for all Models

Question

I have around 40 models in my RoR application. I want to setup a after_save callback for all models. One way is to add it to all models. Since this callback has the same cod

Answer 1

You should use observers for this:

class AuditObserver < ActiveRecord::Observer      

  observe ActiveRecord::Base.send(:subclasses)

  def after_save(record)
    AuditTrail.new(record, "UPDATED")
  end
end

In order to activate an observer, list it in the config.active_record.observers configuration setting in your config/application.rb file.

config.active_record.observers = :audit_observer

Note

In Rails 4, the observer feature is removed from core. Use the https://github.com/rails/rails-observers gem.