task runner

main.go

package main

import (
	"fmt"
	"log"
	"net/http"
	"strconv"
	"time"
)

func main() {
	http.HandleFunc("/task", func(w http.ResponseWriter, r *http.Request) {
		if err := handler(r); err != nil {
			w.WriteHeader(500)
			_, _ = w.Write([]byte(err.Error()))
			return
		}
		w.WriteHeader(200)
	})
	err := http.ListenAndServe(":8080", nil)
	if err != nil {
		log.Fatal(err)
	}
}

func handler(r *http.Request) error {
	q := r.URL.Query()
	message := q.Get("message")

	duration, err := strconv.Atoi(q.Get("duration"))
	if err != nil {
		return fmt.Errorf("duration: %w", err)
	}

	delay, err := strconv.Atoi(q.Get("delay"))
	if err != nil {
		return fmt.Errorf("delay: %w", err)
	}

	time.AfterFunc(time.Duration(delay)*time.Second, func() {
		task(message, time.Duration(duration)*time.Second)
	})
	return nil
}

func task(message string, duration time.Duration) {
	log.Printf("task %v started", message)
	time.Sleep(duration)
	log.Printf("task %v finished", message)
}