attach_to

# File activesupport/lib/active_support/subscriber.rb, line 35
      def attach_to(namespace, subscriber = new, notifier = ActiveSupport::Notifications, inherit_all: false)
        @namespace  = namespace
        @subscriber = subscriber
        @notifier   = notifier
        @inherit_all = inherit_all

        subscribers << subscriber

        # Add event subscribers for all existing methods on the class.
        fetch_public_methods(subscriber, inherit_all).each do |event|
          add_event_subscriber(event)
        end
      end