h2demo.go 16 KB
Newer Older
zhangweiwei's avatar
init  
zhangweiwei committed
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546
// Copyright 2014 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// +build h2demo

package main

import (
	"bytes"
	"context"
	"crypto/tls"
	"flag"
	"fmt"
	"hash/crc32"
	"image"
	"image/jpeg"
	"io"
	"io/ioutil"
	"log"
	"net"
	"net/http"
	"path"
	"regexp"
	"runtime"
	"strconv"
	"strings"
	"sync"
	"time"

	"cloud.google.com/go/storage"
	"go4.org/syncutil/singleflight"
	"golang.org/x/build/autocertcache"
	"golang.org/x/crypto/acme/autocert"
	"golang.org/x/net/http2"
)

var (
	prod = flag.Bool("prod", false, "Whether to configure itself to be the production http2.golang.org server.")

	httpsAddr = flag.String("https_addr", "localhost:4430", "TLS address to listen on ('host:port' or ':port'). Required.")
	httpAddr  = flag.String("http_addr", "", "Plain HTTP address to listen on ('host:port', or ':port'). Empty means no HTTP.")

	hostHTTP  = flag.String("http_host", "", "Optional host or host:port to use for http:// links to this service. By default, this is implied from -http_addr.")
	hostHTTPS = flag.String("https_host", "", "Optional host or host:port to use for http:// links to this service. By default, this is implied from -https_addr.")
)

func homeOldHTTP(w http.ResponseWriter, r *http.Request) {
	io.WriteString(w, `<html>
<body>
<h1>Go + HTTP/2</h1>
<p>Welcome to <a href="https://golang.org/">the Go language</a>'s <a href="https://http2.github.io/">HTTP/2</a> demo & interop server.</p>
<p>Unfortunately, you're <b>not</b> using HTTP/2 right now. To do so:</p>
<ul>
   <li>Use Firefox Nightly or go to <b>about:config</b> and enable "network.http.spdy.enabled.http2draft"</li>
   <li>Use Google Chrome Canary and/or go to <b>chrome://flags/#enable-spdy4</b> to <i>Enable SPDY/4</i> (Chrome's name for HTTP/2)</li>
</ul>
<p>See code & instructions for connecting at <a href="https://github.com/golang/net/tree/master/http2">https://github.com/golang/net/tree/master/http2</a>.</p>

</body></html>`)
}

func home(w http.ResponseWriter, r *http.Request) {
	if r.URL.Path != "/" {
		http.NotFound(w, r)
		return
	}
	io.WriteString(w, `<html>
<body>
<h1>Go + HTTP/2</h1>

<p>Welcome to <a href="https://golang.org/">the Go language</a>'s <a
href="https://http2.github.io/">HTTP/2</a> demo & interop server.</p>

<p>Congratulations, <b>you're using HTTP/2 right now</b>.</p>

<p>This server exists for others in the HTTP/2 community to test their HTTP/2 client implementations and point out flaws in our server.</p>

<p>
The code is at <a href="https://golang.org/x/net/http2">golang.org/x/net/http2</a> and
is used transparently by the Go standard library from Go 1.6 and later.
</p>

<p>Contact info: <i>bradfitz@golang.org</i>, or <a
href="https://golang.org/s/http2bug">file a bug</a>.</p>

<h2>Handlers for testing</h2>
<ul>
  <li>GET <a href="/reqinfo">/reqinfo</a> to dump the request + headers received</li>
  <li>GET <a href="/clockstream">/clockstream</a> streams the current time every second</li>
  <li>GET <a href="/gophertiles">/gophertiles</a> to see a page with a bunch of images</li>
  <li>GET <a href="/serverpush">/serverpush</a> to see a page with server push</li>
  <li>GET <a href="/file/gopher.png">/file/gopher.png</a> for a small file (does If-Modified-Since, Content-Range, etc)</li>
  <li>GET <a href="/file/go.src.tar.gz">/file/go.src.tar.gz</a> for a larger file (~10 MB)</li>
  <li>GET <a href="/redirect">/redirect</a> to redirect back to / (this page)</li>
  <li>GET <a href="/goroutines">/goroutines</a> to see all active goroutines in this server</li>
  <li>PUT something to <a href="/crc32">/crc32</a> to get a count of number of bytes and its CRC-32</li>
  <li>PUT something to <a href="/ECHO">/ECHO</a> and it will be streamed back to you capitalized</li>
</ul>

</body></html>`)
}

func reqInfoHandler(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Content-Type", "text/plain")
	fmt.Fprintf(w, "Method: %s\n", r.Method)
	fmt.Fprintf(w, "Protocol: %s\n", r.Proto)
	fmt.Fprintf(w, "Host: %s\n", r.Host)
	fmt.Fprintf(w, "RemoteAddr: %s\n", r.RemoteAddr)
	fmt.Fprintf(w, "RequestURI: %q\n", r.RequestURI)
	fmt.Fprintf(w, "URL: %#v\n", r.URL)
	fmt.Fprintf(w, "Body.ContentLength: %d (-1 means unknown)\n", r.ContentLength)
	fmt.Fprintf(w, "Close: %v (relevant for HTTP/1 only)\n", r.Close)
	fmt.Fprintf(w, "TLS: %#v\n", r.TLS)
	fmt.Fprintf(w, "\nHeaders:\n")
	r.Header.Write(w)
}

func crcHandler(w http.ResponseWriter, r *http.Request) {
	if r.Method != "PUT" {
		http.Error(w, "PUT required.", 400)
		return
	}
	crc := crc32.NewIEEE()
	n, err := io.Copy(crc, r.Body)
	if err == nil {
		w.Header().Set("Content-Type", "text/plain")
		fmt.Fprintf(w, "bytes=%d, CRC32=%x", n, crc.Sum(nil))
	}
}

type capitalizeReader struct {
	r io.Reader
}

func (cr capitalizeReader) Read(p []byte) (n int, err error) {
	n, err = cr.r.Read(p)
	for i, b := range p[:n] {
		if b >= 'a' && b <= 'z' {
			p[i] = b - ('a' - 'A')
		}
	}
	return
}

type flushWriter struct {
	w io.Writer
}

func (fw flushWriter) Write(p []byte) (n int, err error) {
	n, err = fw.w.Write(p)
	if f, ok := fw.w.(http.Flusher); ok {
		f.Flush()
	}
	return
}

func echoCapitalHandler(w http.ResponseWriter, r *http.Request) {
	if r.Method != "PUT" {
		http.Error(w, "PUT required.", 400)
		return
	}
	if f, ok := w.(http.Flusher); ok {
		f.Flush()
	}
	io.Copy(flushWriter{w}, capitalizeReader{r.Body})
}

var (
	fsGrp   singleflight.Group
	fsMu    sync.Mutex // guards fsCache
	fsCache = map[string]http.Handler{}
)

// fileServer returns a file-serving handler that proxies URL.
// It lazily fetches URL on the first access and caches its contents forever.
func fileServer(url string, latency time.Duration) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if latency > 0 {
			time.Sleep(latency)
		}
		hi, err := fsGrp.Do(url, func() (interface{}, error) {
			fsMu.Lock()
			if h, ok := fsCache[url]; ok {
				fsMu.Unlock()
				return h, nil
			}
			fsMu.Unlock()

			res, err := http.Get(url)
			if err != nil {
				return nil, err
			}
			defer res.Body.Close()
			slurp, err := ioutil.ReadAll(res.Body)
			if err != nil {
				return nil, err
			}

			modTime := time.Now()
			var h http.Handler = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
				http.ServeContent(w, r, path.Base(url), modTime, bytes.NewReader(slurp))
			})
			fsMu.Lock()
			fsCache[url] = h
			fsMu.Unlock()
			return h, nil
		})
		if err != nil {
			http.Error(w, err.Error(), 500)
			return
		}
		hi.(http.Handler).ServeHTTP(w, r)
	})
}

func clockStreamHandler(w http.ResponseWriter, r *http.Request) {
	clientGone := w.(http.CloseNotifier).CloseNotify()
	w.Header().Set("Content-Type", "text/plain")
	ticker := time.NewTicker(1 * time.Second)
	defer ticker.Stop()
	fmt.Fprintf(w, "# ~1KB of junk to force browsers to start rendering immediately: \n")
	io.WriteString(w, strings.Repeat("# xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx\n", 13))

	for {
		fmt.Fprintf(w, "%v\n", time.Now())
		w.(http.Flusher).Flush()
		select {
		case <-ticker.C:
		case <-clientGone:
			log.Printf("Client %v disconnected from the clock", r.RemoteAddr)
			return
		}
	}
}

func registerHandlers() {
	tiles := newGopherTilesHandler()
	push := newPushHandler()

	mux2 := http.NewServeMux()
	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
		switch {
		case r.URL.Path == "/gophertiles":
			tiles.ServeHTTP(w, r) // allow HTTP/2 + HTTP/1.x
			return
		case strings.HasPrefix(r.URL.Path, "/serverpush"):
			push.ServeHTTP(w, r) // allow HTTP/2 + HTTP/1.x
			return
		case r.TLS == nil: // do not allow HTTP/1.x for anything else
			http.Redirect(w, r, "https://"+httpsHost()+"/", http.StatusFound)
			return
		}
		if r.ProtoMajor == 1 {
			if r.URL.Path == "/reqinfo" {
				reqInfoHandler(w, r)
				return
			}
			homeOldHTTP(w, r)
			return
		}
		mux2.ServeHTTP(w, r)
	})
	mux2.HandleFunc("/", home)
	mux2.Handle("/file/gopher.png", fileServer("https://golang.org/doc/gopher/frontpage.png", 0))
	mux2.Handle("/file/go.src.tar.gz", fileServer("https://storage.googleapis.com/golang/go1.4.1.src.tar.gz", 0))
	mux2.HandleFunc("/reqinfo", reqInfoHandler)
	mux2.HandleFunc("/crc32", crcHandler)
	mux2.HandleFunc("/ECHO", echoCapitalHandler)
	mux2.HandleFunc("/clockstream", clockStreamHandler)
	mux2.Handle("/gophertiles", tiles)
	mux2.HandleFunc("/redirect", func(w http.ResponseWriter, r *http.Request) {
		http.Redirect(w, r, "/", http.StatusFound)
	})
	stripHomedir := regexp.MustCompile(`/(Users|home)/\w+`)
	mux2.HandleFunc("/goroutines", func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Content-Type", "text/plain; charset=utf-8")
		buf := make([]byte, 2<<20)
		w.Write(stripHomedir.ReplaceAll(buf[:runtime.Stack(buf, true)], nil))
	})
}

var pushResources = map[string]http.Handler{
	"/serverpush/static/jquery.min.js": fileServer("https://ajax.googleapis.com/ajax/libs/jquery/1.8.2/jquery.min.js", 100*time.Millisecond),
	"/serverpush/static/godocs.js":     fileServer("https://golang.org/lib/godoc/godocs.js", 100*time.Millisecond),
	"/serverpush/static/playground.js": fileServer("https://golang.org/lib/godoc/playground.js", 100*time.Millisecond),
	"/serverpush/static/style.css":     fileServer("https://golang.org/lib/godoc/style.css", 100*time.Millisecond),
}

func newPushHandler() http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		for path, handler := range pushResources {
			if r.URL.Path == path {
				handler.ServeHTTP(w, r)
				return
			}
		}

		cacheBust := time.Now().UnixNano()
		if pusher, ok := w.(http.Pusher); ok {
			for path := range pushResources {
				url := fmt.Sprintf("%s?%d", path, cacheBust)
				if err := pusher.Push(url, nil); err != nil {
					log.Printf("Failed to push %v: %v", path, err)
				}
			}
		}
		time.Sleep(100 * time.Millisecond) // fake network latency + parsing time
		if err := pushTmpl.Execute(w, struct {
			CacheBust int64
			HTTPSHost string
			HTTPHost  string
		}{
			CacheBust: cacheBust,
			HTTPSHost: httpsHost(),
			HTTPHost:  httpHost(),
		}); err != nil {
			log.Printf("Executing server push template: %v", err)
		}
	})
}

func newGopherTilesHandler() http.Handler {
	const gopherURL = "https://blog.golang.org/go-programming-language-turns-two_gophers.jpg"
	res, err := http.Get(gopherURL)
	if err != nil {
		log.Fatal(err)
	}
	if res.StatusCode != 200 {
		log.Fatalf("Error fetching %s: %v", gopherURL, res.Status)
	}
	slurp, err := ioutil.ReadAll(res.Body)
	res.Body.Close()
	if err != nil {
		log.Fatal(err)
	}
	im, err := jpeg.Decode(bytes.NewReader(slurp))
	if err != nil {
		if len(slurp) > 1024 {
			slurp = slurp[:1024]
		}
		log.Fatalf("Failed to decode gopher image: %v (got %q)", err, slurp)
	}

	type subImager interface {
		SubImage(image.Rectangle) image.Image
	}
	const tileSize = 32
	xt := im.Bounds().Max.X / tileSize
	yt := im.Bounds().Max.Y / tileSize
	var tile [][][]byte // y -> x -> jpeg bytes
	for yi := 0; yi < yt; yi++ {
		var row [][]byte
		for xi := 0; xi < xt; xi++ {
			si := im.(subImager).SubImage(image.Rectangle{
				Min: image.Point{xi * tileSize, yi * tileSize},
				Max: image.Point{(xi + 1) * tileSize, (yi + 1) * tileSize},
			})
			buf := new(bytes.Buffer)
			if err := jpeg.Encode(buf, si, &jpeg.Options{Quality: 90}); err != nil {
				log.Fatal(err)
			}
			row = append(row, buf.Bytes())
		}
		tile = append(tile, row)
	}
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		ms, _ := strconv.Atoi(r.FormValue("latency"))
		const nanosPerMilli = 1e6
		if r.FormValue("x") != "" {
			x, _ := strconv.Atoi(r.FormValue("x"))
			y, _ := strconv.Atoi(r.FormValue("y"))
			if ms <= 1000 {
				time.Sleep(time.Duration(ms) * nanosPerMilli)
			}
			if x >= 0 && x < xt && y >= 0 && y < yt {
				http.ServeContent(w, r, "", time.Time{}, bytes.NewReader(tile[y][x]))
				return
			}
		}
		io.WriteString(w, "<html><body onload='showtimes()'>")
		fmt.Fprintf(w, "A grid of %d tiled images is below. Compare:<p>", xt*yt)
		for _, ms := range []int{0, 30, 200, 1000} {
			d := time.Duration(ms) * nanosPerMilli
			fmt.Fprintf(w, "[<a href='https://%s/gophertiles?latency=%d'>HTTP/2, %v latency</a>] [<a href='http://%s/gophertiles?latency=%d'>HTTP/1, %v latency</a>]<br>\n",
				httpsHost(), ms, d,
				httpHost(), ms, d,
			)
		}
		io.WriteString(w, "<p>\n")
		cacheBust := time.Now().UnixNano()
		for y := 0; y < yt; y++ {
			for x := 0; x < xt; x++ {
				fmt.Fprintf(w, "<img width=%d height=%d src='/gophertiles?x=%d&y=%d&cachebust=%d&latency=%d'>",
					tileSize, tileSize, x, y, cacheBust, ms)
			}
			io.WriteString(w, "<br/>\n")
		}
		io.WriteString(w, `<p><div id='loadtimes'></div></p>
<script>
function showtimes() {
	var times = 'Times from connection start:<br>'
	times += 'DOM loaded: ' + (window.performance.timing.domContentLoadedEventEnd - window.performance.timing.connectStart) + 'ms<br>'
	times += 'DOM complete (images loaded): ' + (window.performance.timing.domComplete - window.performance.timing.connectStart) + 'ms<br>'
	document.getElementById('loadtimes').innerHTML = times
}
</script>
<hr><a href='/'>&lt;&lt Back to Go HTTP/2 demo server</a></body></html>`)
	})
}

func httpsHost() string {
	if *hostHTTPS != "" {
		return *hostHTTPS
	}
	if v := *httpsAddr; strings.HasPrefix(v, ":") {
		return "localhost" + v
	} else {
		return v
	}
}

func httpHost() string {
	if *hostHTTP != "" {
		return *hostHTTP
	}
	if v := *httpAddr; strings.HasPrefix(v, ":") {
		return "localhost" + v
	} else {
		return v
	}
}

func serveProdTLS(autocertManager *autocert.Manager) error {
	srv := &http.Server{
		TLSConfig: &tls.Config{
			GetCertificate: autocertManager.GetCertificate,
		},
	}
	http2.ConfigureServer(srv, &http2.Server{
		NewWriteScheduler: func() http2.WriteScheduler {
			return http2.NewPriorityWriteScheduler(nil)
		},
	})
	ln, err := net.Listen("tcp", ":443")
	if err != nil {
		return err
	}
	return srv.Serve(tls.NewListener(tcpKeepAliveListener{ln.(*net.TCPListener)}, srv.TLSConfig))
}

type tcpKeepAliveListener struct {
	*net.TCPListener
}

func (ln tcpKeepAliveListener) Accept() (c net.Conn, err error) {
	tc, err := ln.AcceptTCP()
	if err != nil {
		return
	}
	tc.SetKeepAlive(true)
	tc.SetKeepAlivePeriod(3 * time.Minute)
	return tc, nil
}

func serveProd() error {
	log.Printf("running in production mode")

	storageClient, err := storage.NewClient(context.Background())
	if err != nil {
		log.Fatalf("storage.NewClient: %v", err)
	}
	autocertManager := &autocert.Manager{
		Prompt:     autocert.AcceptTOS,
		HostPolicy: autocert.HostWhitelist("http2.golang.org"),
		Cache:      autocertcache.NewGoogleCloudStorageCache(storageClient, "golang-h2demo-autocert"),
	}

	errc := make(chan error, 2)
	go func() { errc <- http.ListenAndServe(":80", autocertManager.HTTPHandler(http.DefaultServeMux)) }()
	go func() { errc <- serveProdTLS(autocertManager) }()
	return <-errc
}

const idleTimeout = 5 * time.Minute
const activeTimeout = 10 * time.Minute

// TODO: put this into the standard library and actually send
// PING frames and GOAWAY, etc: golang.org/issue/14204
func idleTimeoutHook() func(net.Conn, http.ConnState) {
	var mu sync.Mutex
	m := map[net.Conn]*time.Timer{}
	return func(c net.Conn, cs http.ConnState) {
		mu.Lock()
		defer mu.Unlock()
		if t, ok := m[c]; ok {
			delete(m, c)
			t.Stop()
		}
		var d time.Duration
		switch cs {
		case http.StateNew, http.StateIdle:
			d = idleTimeout
		case http.StateActive:
			d = activeTimeout
		default:
			return
		}
		m[c] = time.AfterFunc(d, func() {
			log.Printf("closing idle conn %v after %v", c.RemoteAddr(), d)
			go c.Close()
		})
	}
}

func main() {
	var srv http.Server
	flag.BoolVar(&http2.VerboseLogs, "verbose", false, "Verbose HTTP/2 debugging.")
	flag.Parse()
	srv.Addr = *httpsAddr
	srv.ConnState = idleTimeoutHook()

	registerHandlers()

	if *prod {
		*hostHTTP = "http2.golang.org"
		*hostHTTPS = "http2.golang.org"
		log.Fatal(serveProd())
	}

	url := "https://" + httpsHost() + "/"
	log.Printf("Listening on " + url)
	http2.ConfigureServer(&srv, &http2.Server{})

	if *httpAddr != "" {
		go func() {
			log.Printf("Listening on http://" + httpHost() + "/ (for unencrypted HTTP/1)")
			log.Fatal(http.ListenAndServe(*httpAddr, nil))
		}()
	}

	go func() {
		log.Fatal(srv.ListenAndServeTLS("server.crt", "server.key"))
	}()
	select {}
}