Playing with context

app.go

package main

import (
	"fmt"
	"time"

	"golang.org/x/net/context"
)

func main() {
	someHandler()
}

func someHandler() {
	ctx, cancel := context.WithCancel(context.Background())

	for i := 0; i < 5; i++ {
		go doStuff(ctx, i)
	}

	time.Sleep(time.Second * 6)
	cancel()
	time.Sleep(time.Second * time.Duration(2))
}

func doStuff(ctx context.Context, num int) {
	for {
		select {
		case <-ctx.Done():
			fmt.Println("Done working")
			return
		default:
			fmt.Println("go", num, "working")
		}
		time.Sleep(time.Second)
	}
}