package main

import (
	"flag"
	"io"
	"log"
	"net/http"
	"strconv"
	"time"
)

var addr = flag.String("addr", ":80", "http service address") // Q=17, R=18

func reqs(x chan int64) {
	var r int
	var bytes int64
	r = 0
	bytes = 0
	tck := time.NewTicker(1e9)
	for {
		select {
		case b := <-x:
			r += 1
			bytes += b
		case <-tck.C:
			if r != 0 {
				log.Print(r, " req/s, ", bytes, " bytes/s")
				r = 0
				bytes = 0
			}
		}
	}
}

var X chan int64

func main() {
	flag.Parse()
	X = make(chan int64, 4096)
	go reqs(X)
	http.Handle("/", http.HandlerFunc(QR))
	err := http.ListenAndServe(*addr, nil)
	if err != nil {
		log.Fatal("ListenAndServe:", err)
	}
}

func QR(w http.ResponseWriter, req *http.Request) {
	var body = "OK"
	w.Header().Set("Content-Type", "text/plain")
	w.Header().Set("Content-Length", strconv.Itoa(len(body)))
	io.WriteString(w, body)
	X <- req.ContentLength
}