Limit http requests to 5 per second in golang

golimit.go

package main

import (
	"context"
	"fmt"
	"log"
	"net/http"
	"sync"
	"time"

	"golang.org/x/time/rate"
)

var url = "http://localhost:8888/"

func main() {
	start := time.Now()

	// Have a max rate of 5/sec; allow bursts of up-to 5.
	rlim := rate.NewLimiter(5, 5)
	var wg sync.WaitGroup

	for i := 0; i < 30; i++ {
		wg.Add(1)
		go func() {
			defer wg.Done()

			// Wait for the rate limiter.
			rlim.Wait(context.Background())

			// make up to 3 attemps to fetch URL
			for i := 1; i <= 3; i++ {
				resp, err := http.Get(url)
				if err != nil {
					log.Println(err)
					continue
				}
				fmt.Println(" status: ", resp.Status, " attempt: ", i)
				if resp.StatusCode == 200 {
					break
				}
			}
		}()
	}
	wg.Wait()

	elapsed := time.Since(start)
	fmt.Println("Fetched 30 urls in", elapsed)
}