Go context with timeout: https://goplay.space/#oPYIR4Y3xAM

main.go

package main

import (
	"context"
	"fmt"
	"time"
)

func ctxSafe(ctx context.Context) {
	for {
		select {
		case <-ctx.Done():
			fmt.Println("context done")
			return
		default:
			time.Sleep(time.Second)
			fmt.Printf("handling %s\n", time.Now().String())
		}
	}
}

func notSafe(ctx context.Context) {
	fmt.Println("before")
	ctxSafe(ctx)
	fmt.Println("after")
}

func main() {
	ctx, _ := context.WithTimeout(context.Background(), time.Second*3)

	notSafe(ctx)
}

// T+00.000000before
// T+01.000000handling 2009-11-10 23:00:01 +0000 UTC m=+1.000000001
// T+02.000000handling 2009-11-10 23:00:02 +0000 UTC m=+2.000000001
// T+03.000000handling 2009-11-10 23:00:03 +0000 UTC m=+3.000000001
// context done
// after