A quick Go script, testing the performance of using concurrent channels for HTTP requests.

concurrent_http.go

/**
 * A quick Go script, testing the performance of using
 * concurrent channels for HTTP requests.
 *
 * Example:
 * 	$ go run concurrent_http.go https://google.com https://facebook.com
 *
 *	-- Consecutive --
 * 	GET: https://google.com
 * 	0.61 elapsed with response length: 10711 https://google.com
 * 	GET: https://facebook.com
 * 	0.42 elapsed with response length: 218651 https://facebook.com
 * 	-- 1.09s elapsed --
 *
 * 	-- Concurrent --
 * 	GET: https://google.com
 * 	GET: https://facebook.com
 * 	0.17 elapsed with response length: 10668 https://google.com
 * 	0.24 elapsed with response length: 219005 https://facebook.com
 * 	-- 0.25s elapsed --
 *
 * Author: Pat Migliaccio <pat@patmigliaccio.com>
 * License: MIT
 */

package main

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

func main() {
	Consecutive(os.Args)
	Concurrent(os.Args)
}

// Consecutive makes HTTP requests consecutively
func Consecutive(args []string) {
	fmt.Println("\n-- Consecutive --")

	startOne := time.Now()
	for _, url := range os.Args[1:] {
		fmt.Printf("GET: %s\n", url)
		MakeRequest(url)
	}

	fmt.Printf("-- %.2fs elapsed --\n\n", time.Since(startOne).Seconds())
}

// Concurrent makes HTTP requests concurrently in GoRoutines
func Concurrent(args []string) {
	fmt.Println("-- Concurrent --")

	startTwo := time.Now()
	ch := make(chan string)
	for _, url := range args[1:] {
		fmt.Printf("GET: %s\n", url)
		go MakeRequestConcurrent(url, ch)
	}

	for range args[1:] {
		fmt.Println(<-ch)
	}

	fmt.Printf("-- %.2fs elapsed --\n\n", time.Since(startTwo).Seconds())
}

// MakeRequest calls an HTTP Get Request
func MakeRequest(url string) {
	start := time.Now()
	resp, _ := http.Get(url)

	secs := time.Since(start).Seconds()
	body, _ := ioutil.ReadAll(resp.Body)
	fmt.Printf("%.2f elapsed with response length: %d %s\n", secs, len(body), url)
}

// MakeRequestConcurrent calls an HTTP Get Request concurrently
func MakeRequestConcurrent(url string, ch chan<- string) {
	start := time.Now()
	resp, _ := http.Get(url)

	secs := time.Since(start).Seconds()
	body, _ := ioutil.ReadAll(resp.Body)
	ch <- fmt.Sprintf("%.2f elapsed with response length: %d %s", secs, len(body), url)
}