Golang simple signal dispatcher

signal_dispatcher.go

package signal_dispatcher

import (
	"os"
	"os/signal"
)

type SignalSubscriber interface {
	GetSubscribesSignals() *map[os.Signal]bool
	Notify(os.Signal)
}
type SignalSubscriberCallback struct {
	signals  *map[os.Signal]bool
	callback func(os.Signal)
}

func (s *SignalSubscriberCallback) GetSubscribesSignals() *map[os.Signal]bool {
	return s.signals
}

func (s *SignalSubscriberCallback) Notify(signal os.Signal) {
	s.callback(signal)
}

type SignalDispatcher struct {
	signalChan  chan os.Signal
	stopChan    chan bool
	subscribers []SignalSubscriber
}

func (s *SignalDispatcher) Subscribe(callback func(os.Signal), sig ...os.Signal) *SignalDispatcher {
	var signals *map[os.Signal]bool
	if sig != nil {
		signals := &map[os.Signal]bool{}
		for _, s := range sig {
			(*signals)[s] = true
		}
	}
	s.subscribers = append(s.subscribers, &SignalSubscriberCallback{callback: callback, signals: signals})
	return s
}

func (s *SignalDispatcher) Listen() *SignalDispatcher {
	s.signalChan = make(chan os.Signal, 1)
	s.stopChan = make(chan bool, 1)
	signal.Notify(s.signalChan)
	go func() {
		for {
			select {
			case <-s.stopChan:
				signal.Stop(s.signalChan)
				close(s.stopChan)
				close(s.signalChan)
				return
			case sig := <-s.signalChan:
				for _, subscriber := range s.subscribers {
					signals := subscriber.GetSubscribesSignals()
					if signals != nil {
						if _, ok := (*signals)[sig]; !ok {
							continue
						}
					}
					subscriber.Notify(sig)
				}
			}
		}
	}()
	return s
}

func (s *SignalDispatcher) Stop() *SignalDispatcher {
	s.stopChan <- true
	return s
}

See https://gist.github.com/instabledesign/494ffc8bafd5781bb4d43dbe2111cc30
and https://github.com/gol4ng/signal