zammad/app/models/concerns/has_online_notifications.rb

# Copyright (C) 2012-2016 Zammad Foundation, http://zammad-foundation.org/
module HasOnlineNotifications
  extend ActiveSupport::Concern

  included do
    before_destroy :online_notification_destroy
  end

=begin

delete object online notification list, will be executed automatically

  model = Model.find(123)
  model.online_notification_destroy

=end

  def online_notification_destroy
    OnlineNotification.remove(self.class.to_s, id)
  end
end