Ruby publisher/subscriber event model

EventSubscription.rb

module EventPublisher
    attr_reader :events
    attr_reader :subscribers

    def register_events(events)
      @subscribers = {}
      @events = events
    end
  
    def publish_event(event)
      @subscribers[event].each do | subscriber |
        subscriber.call event
      end
    end
    
    def event_subscribe(event_name, event_handler)
      @subscribers[event_name] = [] if !@subscribers[event_name]
      @subscribers[event_name] << event_handler
    end
    
    def event_unsubscribe(event_name, event_handler)
      @subscribers[event_name].delete_if { |handler| handler == event_handler }
    end
end

class MyEventPublisher
  include EventPublisher
  
  def initialize()
    register_events :my_custom_event
  end
  
  def my_custom_event()
    publish_event :my_custom_event
  end
end

class MyEventSubscriber
  def handle_event(event)
    puts "Handled #{event}"
  end
end

class MyOtherEventSubscriber
  def handle_event(event)
    puts "Also handled #{event}"
  end
end

publisher = MyEventPublisher.new
subscriber = MyEventSubscriber.new
subscriber2 = MyOtherEventSubscriber.new

publisher.event_subscribe :my_custom_event, subscriber.method(:handle_event)
publisher.event_subscribe :my_custom_event, subscriber2.method(:handle_event)
publisher.my_custom_event