Go version of AB

go-ab

package main

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

var url string

func get(start, done chan bool) {
	var err os.Error
	var resp *http.Response
	for {
		<-start
		resp, _, err = http.Get(url)
		if err != nil {
			fmt.Printf("%v\n", err)
		} else {
			ioutil.ReadAll(resp.Body)
			resp.Body.Close()
		}
		done <- true
	}
}

func main() {
	n := flag.Int("n", 1, "total number of requests")
	c := flag.Int("c", 1, "number of parallel requests")
	flag.Parse()
	url = flag.Args()[0] // no defaults

	loop := *n / *c

	done := make(chan bool, *n)
	start := make(chan bool, *n)
	b := time.Nanoseconds()
	for i := 0; i < *c; i++ {
		go get(start, done)
		start <- true // start some goroutines immediately
	}
	for i := *c; i < *n; i++ {
		start <- true // fill in the chan so everybody can work
	}
	for i := 0; i < *n; i++ {
		<-done
		if i % loop == 0 {
			fmt.Printf("%d reqs end in %d msecs\n", i, (time.Nanoseconds()-b)/1e6)
		}
	}
	e := time.Nanoseconds()
	fmt.Printf("time used %d\n", (e-b)/1e6)
}