gistfile1.go

package main

import (
	"fmt"
	"io/ioutil"
	"log"
	"net/http"
	"os"
	"strconv"
	"time"
)

const NANO_TO_MILLI = 1000 * 1000

func main() {
	if len(os.Args) != 4 {
		fmt.Println("usage:", os.Args[0], "url numTests numRequests")
		os.Exit(3)
	}
	numTests, error := strconv.Atoi(os.Args[2])
	if error != nil {
		log.Fatal(error)
		os.Exit(1)
	}
	numRequests, error := strconv.Atoi(os.Args[3])
	if error != nil {
		log.Fatal(error)
		os.Exit(2)
	}
	transport := &http.Transport{
		DisableKeepAlives:   false,
		MaxIdleConnsPerHost: numRequests,
	}
	client := &http.Client{
		Transport: transport,
	}
	for i := 0; i < numTests; i++ {
		runTest(client, numRequests)
	}
}

func runTest(client *http.Client, numRequests int) {
	times := make(chan int64)
	for i := 0; i < numRequests; i++ {
		go getPing(client, times)
	}
	totalTime := int64(0)
	for i := 0; i < numRequests; i++ {
		time := <-times
		totalTime += time
	}
	timeNanoseconds := float64(totalTime) / float64(numRequests)
	timeMilliseconds := timeNanoseconds / NANO_TO_MILLI
	fmt.Println("avg request time:", timeMilliseconds, "ms")
}

func getPing(client *http.Client, times chan int64) {
	start := time.Now()
	response, error := client.Get(os.Args[1])
	if error != nil {
		log.Fatal(error)
	}
	_, error = ioutil.ReadAll(response.Body)
	response.Body.Close()
	times <- time.Since(start).Nanoseconds()
	if error != nil {
		log.Fatal(error)
	}
}