Example showing how to provide a blocking-close for long running processes in golang. The process will run until Close() is called, this call blocks until the process has actually stopped.

quit.go

package main

import (
	"log"
	"time"
)

type Process struct {
	quit chan struct{}
}

func NewProcess() *Process {
	p := &Process{quit: make(chan struct{})}
	go p.run()
	return p
}

func (p *Process) run() {
loop:
	for {
		select {
		case <-time.After(time.Second):
			log.Println("tick")

		case <-p.quit:
			log.Println("break")

			// simulate closing long task
			time.Sleep(5 * time.Second)

			break loop
		}
	}

	// signal end of run()
	close(p.quit)
}

func (p *Process) Close() {
	// tell loop to break
	p.quit <- struct{}{}

	// wait for run() to finish
	<-p.quit
}

func main() {
	proc := NewProcess()

	time.Sleep(2 * time.Second)

	log.Println("closing proc")
	proc.Close()
	log.Println("proc closed")
}