nanoninja/README.md

## README.md

      
    Raw
  

              README.md
            
          
    Websocket Go chat

Installation

After installing Go and setting up your
GOPATH
go get golang.org/x/net/websocket

Running chat

# Add your personnal ip as 192.168.*.* or your domain as www.example.com

go run main.go -addr=0.0.0.0:3000 
Open your favorite browser : http://localhost:3000

  
## index.html
<!DOCTYPE html>
<html lang="en" dir="ltr">

<head>
    <meta charset="UTF-8">
    <title>Websocket</title>
    <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=0" />
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous" />
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap-theme.min.css" integrity="sha384-rHyoN1iRsVXV4nD0JutlnGaslCJuC7uwjduW9SVrLvRYooPp2bWYgmgJQIXwl/Sp" crossorigin="anonymous" />
    <style>
        #messages {
            height: 120px;
            overflow: scroll;
            padding: 20px;
        }
        #messages div {
            margin-bottom: 4px;
        }
    </style>
</head>

<body>
    <div class="container">
        <h1>Websocket</h1>
        <div class="col">
            <div class="form-group">
                <input type="text" id="username" class="form-control" placeholder="Username" />
            </div>
            <div class="form-group">
                <textarea id="text" class="form-control" placeholder="Write a message and press enter..."></textarea>
            </div>
        </div>
        <div>
            <h3>Messages:</h3>
            <div id="messages" class="pre-scrollable well"></div>
        </div>
    </div>

    <script src="https://code.jquery.com/jquery-2.2.4.min.js" integrity="sha256-BbhdlvQf/xTY9gja0Dq3HiwQF8LaCRTXxZKRutelT44=" crossorigin="anonymous"></script>
    <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js" integrity="sha384-Tc5IQib027qvyjSMfHjOMaLkfuWVxZxUPnCJA7l2mCWNIpG9mGCD8wGNIcPD7Txa" crossorigin="anonymous"></script>

    <script type="text/javascript">
        $(document).ready(function () {
            var ws = new WebSocket('ws://' + location.host + '/echo');
            var username = '';

            ws.onopen = function () {
                console.log('Connected');
            };

            ws.onclose = function () {
                alert('Disconnected');
            }

            ws.onmessage = function (e) {
                console.log(e.data);

                var m = JSON.parse(e.data);
                var div = document.createElement('div');
                var strg = document.createElement('strong');

                strg.appendChild(document.createTextNode(m.username + ': '));
                div.appendChild(strg);
                div.appendChild(document.createTextNode(m.text));
                $(div).hide().appendTo('#messages').fadeIn(300);
            };

            ws.onerror = function (e) {
                console.debug(e.data);
            };

            $(document).on('keypress', '#text', function (e) {
                if (e.keyCode == 13) {
                    e.preventDefault();

                    if (username === '') {
                        username = $('#username').val();
                    }
                    var text = $(this);
                    var msg = {
                        username: username,
                        text: text.val()
                    };

                    if (text.val() !== '') {
                        ws.send(JSON.stringify(msg));
                        text.val('');
                    }
                }
            });
        });

        setInterval(animateScroll($('#messages')), 3000);

        function animateScroll(elem) {
            return function () {
                elem.animate({
                    scrollTop: elem[0].scrollHeight
                }, 1000);
            }
        }
    </script>
</body>

</html>

## main.go
// Copyright 2017 The Nanoninja Authors. All rights reserved.

package main

import (
	"flag"
	"html/template"
	"io"
	"log"
	"net/http"

	"golang.org/x/net/websocket"
)

var (
	addr = flag.String("addr", "0.0.0.0:3000", "host:port")
	chat = NewChat()
)

func main() {
	flag.Parse()
	go chat.Run()

	http.HandleFunc("/", indexHandler)
	http.HandleFunc("/echo", webSocketHandler)

	if err := http.ListenAndServe(*addr, nil); err != nil {
		panic(err.Error())
	}
}

func indexHandler(w http.ResponseWriter, r *http.Request) {
	t, err := template.ParseFiles("index.html")
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
	}
	err = t.Execute(w, nil)
}

type User struct {
	Name   string
	Addr   string
	Output chan Message
}

type Message struct {
	Username string `json:"username"`
	Text     string `json:"text"`
}

type Chat struct {
	Users map[string]User
	Join  chan User
	Leave chan User
	Input chan Message
}

func NewChat() *Chat {
	return &Chat{
		Users: make(map[string]User),
		Join:  make(chan User),
		Leave: make(chan User),
		Input: make(chan Message),
	}
}

func (c *Chat) Run() {
	for {
		select {
		case user := <-c.Join:
			c.Users[user.Name] = user
		case user := <-c.Leave:
			delete(c.Users, user.Name)
		case msg := <-c.Input:
			for _, user := range c.Users {
				user.Output <- msg
			}
		}
	}
}

func webSocketServer(ws *websocket.Conn) {
	defer ws.Close()

	user := User{
		Output: make(chan Message),
		Addr:   ws.Request().RemoteAddr,
	}
	defer func() {
		chat.Leave <- user
	}()

	go func() {
		for {
			m := Message{}
			if err := websocket.JSON.Receive(ws, &m); err != nil {
				if err == io.EOF {
					log.Printf("%s has disconnected", user.Name)
					chat.Leave <- user
					break
				}
			}
			user.Name = m.Username
			chat.Join <- user

			m.Text = textLimit(255)(m.Text)
			chat.Input <- m

			addr := chat.Users[m.Username].Addr
			log.Printf("[%s] %s: %s\n", addr, m.Username, m.Text)
		}
	}()

	for msg := range user.Output {
		if err := websocket.JSON.Send(ws, msg); err != nil {
			log.Println(err)
			break
		}
	}
}

func webSocketHandler(w http.ResponseWriter, r *http.Request) {
	s := websocket.Server{Handler: websocket.Handler(webSocketServer)}
	s.ServeHTTP(w, r)
}

type filter func(s string) string

func textLimit(length int) filter {
	return func(s string) string {
		if len(s) > length {
			return s[:length]
		}
		return s
	}
}
	<!DOCTYPE html>
	<html lang="en" dir="ltr">

	<head>
	<meta charset="UTF-8">
	<title>Websocket</title>
	<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=0" />
	<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous" />
	<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap-theme.min.css" integrity="sha384-rHyoN1iRsVXV4nD0JutlnGaslCJuC7uwjduW9SVrLvRYooPp2bWYgmgJQIXwl/Sp" crossorigin="anonymous" />
	<style>
	#messages {
	height: 120px;
	overflow: scroll;
	padding: 20px;
	}
	#messages div {
	margin-bottom: 4px;
	}
	</style>
	</head>

	<body>
	<div class="container">
	<h1>Websocket</h1>
	<div class="col">
	<div class="form-group">
	<input type="text" id="username" class="form-control" placeholder="Username" />
	</div>
	<div class="form-group">
	<textarea id="text" class="form-control" placeholder="Write a message and press enter..."></textarea>
	</div>
	</div>
	<div>
	<h3>Messages:</h3>
	<div id="messages" class="pre-scrollable well"></div>
	</div>
	</div>

	<script src="https://code.jquery.com/jquery-2.2.4.min.js" integrity="sha256-BbhdlvQf/xTY9gja0Dq3HiwQF8LaCRTXxZKRutelT44=" crossorigin="anonymous"></script>
	<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js" integrity="sha384-Tc5IQib027qvyjSMfHjOMaLkfuWVxZxUPnCJA7l2mCWNIpG9mGCD8wGNIcPD7Txa" crossorigin="anonymous"></script>

	<script type="text/javascript">
	$(document).ready(function () {
	var ws = new WebSocket('ws://' + location.host + '/echo');
	var username = '';

	ws.onopen = function () {
	console.log('Connected');
	};

	ws.onclose = function () {
	alert('Disconnected');
	}

	ws.onmessage = function (e) {
	console.log(e.data);

	var m = JSON.parse(e.data);
	var div = document.createElement('div');
	var strg = document.createElement('strong');

	strg.appendChild(document.createTextNode(m.username + ': '));
	div.appendChild(strg);
	div.appendChild(document.createTextNode(m.text));
	$(div).hide().appendTo('#messages').fadeIn(300);
	};

	ws.onerror = function (e) {
	console.debug(e.data);
	};

	$(document).on('keypress', '#text', function (e) {
	if (e.keyCode == 13) {
	e.preventDefault();

	if (username === '') {
	username = $('#username').val();
	}
	var text = $(this);
	var msg = {
	username: username,
	text: text.val()
	};

	if (text.val() !== '') {
	ws.send(JSON.stringify(msg));
	text.val('');
	}
	}
	});
	});

	setInterval(animateScroll($('#messages')), 3000);

	function animateScroll(elem) {
	return function () {
	elem.animate({
	scrollTop: elem[0].scrollHeight
	}, 1000);
	}
	}
	</script>
	</body>

	</html>
	// Copyright 2017 The Nanoninja Authors. All rights reserved.

	package main

	import (
	"flag"
	"html/template"
	"io"
	"log"
	"net/http"

	"golang.org/x/net/websocket"
	)

	var (
	addr = flag.String("addr", "0.0.0.0:3000", "host:port")
	chat = NewChat()
	)

	func main() {
	flag.Parse()
	go chat.Run()

	http.HandleFunc("/", indexHandler)
	http.HandleFunc("/echo", webSocketHandler)

	if err := http.ListenAndServe(*addr, nil); err != nil {
	panic(err.Error())
	}
	}

	func indexHandler(w http.ResponseWriter, r *http.Request) {
	t, err := template.ParseFiles("index.html")
	if err != nil {
	http.Error(w, err.Error(), http.StatusInternalServerError)
	}
	err = t.Execute(w, nil)
	}

	type User struct {
	Name string
	Addr string
	Output chan Message
	}

	type Message struct {
	Username string `json:"username"`
	Text string `json:"text"`
	}

	type Chat struct {
	Users map[string]User
	Join chan User
	Leave chan User
	Input chan Message
	}

	func NewChat() *Chat {
	return &Chat{
	Users: make(map[string]User),
	Join: make(chan User),
	Leave: make(chan User),
	Input: make(chan Message),
	}
	}

	func (c *Chat) Run() {
	for {
	select {
	case user := <-c.Join:
	c.Users[user.Name] = user
	case user := <-c.Leave:
	delete(c.Users, user.Name)
	case msg := <-c.Input:
	for _, user := range c.Users {
	user.Output <- msg
	}
	}
	}
	}

	func webSocketServer(ws *websocket.Conn) {
	defer ws.Close()

	user := User{
	Output: make(chan Message),
	Addr: ws.Request().RemoteAddr,
	}
	defer func() {
	chat.Leave <- user
	}()

	go func() {
	for {
	m := Message{}
	if err := websocket.JSON.Receive(ws, &m); err != nil {
	if err == io.EOF {
	log.Printf("%s has disconnected", user.Name)
	chat.Leave <- user
	break
	}
	}
	user.Name = m.Username
	chat.Join <- user

	m.Text = textLimit(255)(m.Text)
	chat.Input <- m

	addr := chat.Users[m.Username].Addr
	log.Printf("[%s] %s: %s\n", addr, m.Username, m.Text)
	}
	}()

	for msg := range user.Output {
	if err := websocket.JSON.Send(ws, msg); err != nil {
	log.Println(err)
	break
	}
	}
	}

	func webSocketHandler(w http.ResponseWriter, r *http.Request) {
	s := websocket.Server{Handler: websocket.Handler(webSocketServer)}
	s.ServeHTTP(w, r)
	}

	type filter func(s string) string

	func textLimit(length int) filter {
	return func(s string) string {
	if len(s) > length {
	return s[:length]
	}
	return s
	}
	}