a working echo client and server using gorilla

Signed-off-by: Jeff Carr <jcarr@wit.com>

example-gorilla/client.go

@@ -0,0 +1,83 @@
+// Copyright 2015 The Gorilla WebSocket 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 ignore
+
+package main
+
+import (
+	"flag"
+	"log"
+	"net/url"
+	"os"
+	"os/signal"
+	"time"
+
+	"github.com/gorilla/websocket"
+)
+
+// var addr = flag.String("addr", "localhost:8080", "http service address")
+var addr = flag.String("addr", "v000185.testing.com.customers.wprod.wit.com:9000", "http service address")
+
+func main() {
+	flag.Parse()
+	log.SetFlags(0)
+
+	interrupt := make(chan os.Signal, 1)
+	signal.Notify(interrupt, os.Interrupt)
+
+	u := url.URL{Scheme: "ws", Host: *addr, Path: "/echo"}
+	log.Printf("connecting to %s", u.String())
+
+	c, _, err := websocket.DefaultDialer.Dial(u.String(), nil)
+	if err != nil {
+		log.Fatal("dial:", err)
+	}
+	defer c.Close()
+
+	done := make(chan struct{})
+
+	go func() {
+		defer close(done)
+		for {
+			_, message, err := c.ReadMessage()
+			if err != nil {
+				log.Println("read:", err)
+				return
+			}
+			log.Printf("recv: %s", message)
+		}
+	}()
+
+	ticker := time.NewTicker(time.Second)
+	defer ticker.Stop()
+
+	for {
+		select {
+		case <-done:
+			return
+		case t := <-ticker.C:
+			err := c.WriteMessage(websocket.TextMessage, []byte(t.String()))
+			if err != nil {
+				log.Println("write:", err)
+				return
+			}
+		case <-interrupt:
+			log.Println("interrupt")
+
+			// Cleanly close the connection by sending a close message and then
+			// waiting (with timeout) for the server to close the connection.
+			err := c.WriteMessage(websocket.CloseMessage, websocket.FormatCloseMessage(websocket.CloseNormalClosure, ""))
+			if err != nil {
+				log.Println("write close:", err)
+				return
+			}
+			select {
+			case <-done:
+			case <-time.After(time.Second):
+			}
+			return
+		}
+	}
+}

example-gorilla/server.go

@@ -0,0 +1,268 @@
+// Copyright 2013 The Gorilla WebSocket Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Command server is a test server for the Autobahn WebSockets Test Suite.
+package main
+
+import (
+	"errors"
+	"flag"
+	"io"
+	"log"
+	"net/http"
+	"time"
+	"unicode/utf8"
+
+	"github.com/gorilla/websocket"
+)
+
+var upgrader = websocket.Upgrader{
+	ReadBufferSize:    4096,
+	WriteBufferSize:   4096,
+	EnableCompression: true,
+	CheckOrigin: func(r *http.Request) bool {
+		return true
+	},
+}
+
+// echoCopy echoes messages from the client using io.Copy.
+func echoCopy(w http.ResponseWriter, r *http.Request, writerOnly bool) {
+	conn, err := upgrader.Upgrade(w, r, nil)
+	if err != nil {
+		log.Println("Upgrade:", err)
+		return
+	}
+	defer conn.Close()
+	for {
+		mt, r, err := conn.NextReader()
+		if err != nil {
+			if err != io.EOF {
+				log.Println("NextReader:", err)
+			}
+			return
+		}
+		if mt == websocket.TextMessage {
+			r = &validator{r: r}
+		}
+		w, err := conn.NextWriter(mt)
+		if err != nil {
+			log.Println("NextWriter:", err)
+			return
+		}
+		if mt == websocket.TextMessage {
+			r = &validator{r: r}
+		}
+		if writerOnly {
+			_, err = io.Copy(struct{ io.Writer }{w}, r)
+		} else {
+			_, err = io.Copy(w, r)
+		}
+		if err != nil {
+			if err == errInvalidUTF8 {
+				conn.WriteControl(websocket.CloseMessage,
+					websocket.FormatCloseMessage(websocket.CloseInvalidFramePayloadData, ""),
+					time.Time{})
+			}
+			log.Println("Copy:", err)
+			return
+		}
+		err = w.Close()
+		if err != nil {
+			log.Println("Close:", err)
+			return
+		}
+	}
+}
+
+func echoCopyWriterOnly(w http.ResponseWriter, r *http.Request) {
+	echoCopy(w, r, true)
+}
+
+func echoCopyFull(w http.ResponseWriter, r *http.Request) {
+	echoCopy(w, r, false)
+}
+
+// echoReadAll echoes messages from the client by reading the entire message
+// with ioutil.ReadAll.
+func echoReadAll(w http.ResponseWriter, r *http.Request, writeMessage, writePrepared bool) {
+	conn, err := upgrader.Upgrade(w, r, nil)
+	if err != nil {
+		log.Println("Upgrade:", err)
+		return
+	}
+	defer conn.Close()
+	for {
+		mt, b, err := conn.ReadMessage()
+		if err != nil {
+			if err != io.EOF {
+				log.Println("NextReader:", err)
+			}
+			return
+		}
+		if mt == websocket.TextMessage {
+			if !utf8.Valid(b) {
+				conn.WriteControl(websocket.CloseMessage,
+					websocket.FormatCloseMessage(websocket.CloseInvalidFramePayloadData, ""),
+					time.Time{})
+				log.Println("ReadAll: invalid utf8")
+			}
+		}
+		if writeMessage {
+			if !writePrepared {
+				err = conn.WriteMessage(mt, b)
+				if err != nil {
+					log.Println("WriteMessage:", err)
+				}
+			} else {
+				pm, err := websocket.NewPreparedMessage(mt, b)
+				if err != nil {
+					log.Println("NewPreparedMessage:", err)
+					return
+				}
+				err = conn.WritePreparedMessage(pm)
+				if err != nil {
+					log.Println("WritePreparedMessage:", err)
+				}
+			}
+		} else {
+			w, err := conn.NextWriter(mt)
+			if err != nil {
+				log.Println("NextWriter:", err)
+				return
+			}
+			if _, err := w.Write(b); err != nil {
+				log.Println("Writer:", err)
+				return
+			}
+			if err := w.Close(); err != nil {
+				log.Println("Close:", err)
+				return
+			}
+		}
+	}
+}
+
+func echoReadAllWriter(w http.ResponseWriter, r *http.Request) {
+	echoReadAll(w, r, false, false)
+}
+
+func echoReadAllWriteMessage(w http.ResponseWriter, r *http.Request) {
+	echoReadAll(w, r, true, false)
+}
+
+func echoReadAllWritePreparedMessage(w http.ResponseWriter, r *http.Request) {
+	echoReadAll(w, r, true, true)
+}
+
+func serveHome(w http.ResponseWriter, r *http.Request) {
+	if r.URL.Path != "/" {
+		http.Error(w, "Not found.", http.StatusNotFound)
+		return
+	}
+	if r.Method != "GET" {
+		http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+	w.Header().Set("Content-Type", "text/html; charset=utf-8")
+	io.WriteString(w, "<html><body>Echo Server</body></html>")
+}
+
+var addr = flag.String("addr", ":9000", "http service address")
+
+func main() {
+	flag.Parse()
+	http.HandleFunc("/", serveHome)
+	http.HandleFunc("/c", echoCopyWriterOnly)
+	http.HandleFunc("/f", echoCopyFull)
+	http.HandleFunc("/echo", echoCopyFull)
+	http.HandleFunc("/r", echoReadAllWriter)
+	http.HandleFunc("/m", echoReadAllWriteMessage)
+	http.HandleFunc("/p", echoReadAllWritePreparedMessage)
+
+	log.Println("Starting http.ListenAndServe() on port 9000")
+	err := http.ListenAndServe(*addr, nil)
+	if err != nil {
+		log.Fatal("ListenAndServe: ", err)
+	}
+}
+
+type validator struct {
+	state int
+	x     rune
+	r     io.Reader
+}
+
+var errInvalidUTF8 = errors.New("invalid utf8")
+
+func (r *validator) Read(p []byte) (int, error) {
+	n, err := r.r.Read(p)
+	state := r.state
+	x := r.x
+	for _, b := range p[:n] {
+		state, x = decode(state, x, b)
+		if state == utf8Reject {
+			break
+		}
+	}
+	r.state = state
+	r.x = x
+	if state == utf8Reject || (err == io.EOF && state != utf8Accept) {
+		return n, errInvalidUTF8
+	}
+	return n, err
+}
+
+// UTF-8 decoder from http://bjoern.hoehrmann.de/utf-8/decoder/dfa/
+//
+// Copyright (c) 2008-2009 Bjoern Hoehrmann <bjoern@hoehrmann.de>
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to
+// deal in the Software without restriction, including without limitation the
+// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+// sell copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+// IN THE SOFTWARE.
+var utf8d = [...]byte{
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 00..1f
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 20..3f
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 40..5f
+	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // 60..7f
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, // 80..9f
+	7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, // a0..bf
+	8, 8, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, // c0..df
+	0xa, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x3, 0x4, 0x3, 0x3, // e0..ef
+	0xb, 0x6, 0x6, 0x6, 0x5, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, 0x8, // f0..ff
+	0x0, 0x1, 0x2, 0x3, 0x5, 0x8, 0x7, 0x1, 0x1, 0x1, 0x4, 0x6, 0x1, 0x1, 0x1, 0x1, // s0..s0
+	1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 1, 1, // s1..s2
+	1, 2, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, // s3..s4
+	1, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 3, 1, 1, 1, 1, 1, 1, // s5..s6
+	1, 3, 1, 1, 1, 1, 1, 3, 1, 3, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // s7..s8
+}
+
+const (
+	utf8Accept = 0
+	utf8Reject = 1
+)
+
+func decode(state int, x rune, b byte) (int, rune) {
+	t := utf8d[b]
+	if state != utf8Accept {
+		x = rune(b&0x3f) | (x << 6)
+	} else {
+		x = rune((0xff >> t) & b)
+	}
+	state = int(utf8d[256+state*16+int(t)])
+	return state, x
+}