Bonjour,
j'ai suit un tutoriel d'une application de chat en temps réel avec nodeJS,mais j'ai toujours ces erreurs:

Code : Sélectionner tout - Visualiser dans une fenêtre à part
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
C:\xampp\htdocs\chat>node app.js
   info  - socket.io started
Express server listening on port 3000
GET /chat 200 210ms - 686
 
http.js:690
    throw new Error('Can\'t set headers after they are sent.');
          ^
Error: Can't set headers after they are sent.
    at ServerResponse.OutgoingMessage.setHeader (http.js:690:11)
    at ServerResponse.res.setHeader (C:\xampp\htdocs\chat\node_modules\express\n
ode_modules\connect\lib\patch.js:59:22)
    at next (C:\xampp\htdocs\chat\node_modules\express\node_modules\connect\lib\
proto.js:153:13)
    at Function.app.handle (C:\xampp\htdocs\chat\node_modules\express\node_modul
es\connect\lib\proto.js:198:3)
    at Server.app (C:\xampp\htdocs\chat\node_modules\express\node_modules\connec
t\lib\connect.js:66:31)
    at Manager.handleRequest (C:\xampp\htdocs\chat\node_modules\socket.io\lib\ma
nager.js:564:28)
    at Server.<anonymous> (C:\xampp\htdocs\chat\node_modules\socket.io\lib\manag
er.js:118:10)
    at Server.emit (events.js:117:20)
    at HTTPParser.parser.onIncoming (http.js:2113:12)
    at HTTPParser.parserOnHeadersComplete [as onHeadersComplete] (http.js:122:23
)
les dépendances:

Code : Sélectionner tout - Visualiser dans une fenêtre à part
1
2
3
4
5
6
7
8
9
10
11
12
13
{
  "name": "application-name",
  "version": "0.0.1",
  "private": true,
  "scripts": {
    "start": "node app.js"
  },
  "dependencies": {
    "express": "3.0.0rc4",
    "socket.io": "0.9.10",
    "jade": "*"
  }
}
et le fichier app.js

Code : Sélectionner tout - Visualiser dans une fenêtre à part
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
var express = require('express')
  , routes = require('./routes')
  , user = require('./routes/user')
  , chat = require('./routes/chat')
  , socketio = require('socket.io')
  , http = require('http')
  , path = require('path');
 
var app = express();
 
app.configure(function(){
  app.set('port', process.env.PORT || 3000);
  app.set('views', __dirname + '/views');
  app.set('view engine', 'jade');
  app.use(express.favicon());
  app.use(express.logger('dev'));
  app.use(express.bodyParser());
  app.use(express.methodOverride());
  app.use(app.router);
  app.use(express.static(path.join(__dirname, 'public')));
});
 
app.configure('development', function(){
  app.use(express.errorHandler());
});
 
app.get('/', routes.index);
app.get('/chat', chat.main);
app.get('/users', user.list);
 
var server = app.listen(app.get('port'), function(){
  console.log("Express server listening on port " + app.get('port'));
});
 
var io = socketio.listen(server);
 
var clients = {};
var socketsOfClients = {};
 
io.sockets.on('connection', function(socket) {
  socket.on('set username', function(userName) {
    // Is this an existing user name?
    if (clients[userName] === undefined) {
      // Does not exist ... so, proceed
      clients[userName] = socket.id;
      socketsOfClients[socket.id] = userName;
      userNameAvailable(socket.id, userName);
      userJoined(userName);
    } else
    if (clients[userName] === socket.id) {
      // Ignore for now
    } else {
      userNameAlreadyInUse(socket.id, userName);
    }
  });
 
  socket.on('message', function(msg) {
    var srcUser;
    if (msg.inferSrcUser) {
      // Infer user name based on the socket id
      srcUser = socketsOfClients[socket.id];
    } else {
      srcUser = msg.source;
    }
    if (msg.target == "All") {
      // broadcast
      io.sockets.emit('message',
          {"source": srcUser,
           "message": msg.message,
           "target": msg.target});
    } else {
      // Look up the socket id
      io.sockets.sockets[clients[msg.target]].emit('message', 
          {"source": srcUser,
           "message": msg.message,
           "target": msg.target});
    }
  })
 
  socket.on('disconnect', function() {
      var uName = socketsOfClients[socket.id];
      delete socketsOfClients[socket.id];
    delete clients[uName];
    // relay this message to all the clients
    userLeft(uName);
  })
})
 
function userJoined(uName) {
    Object.keys(socketsOfClients).forEach(function(sId) {
        io.sockets.sockets[sId].emit('userJoined', { "userName": uName });
    })
}
 
function userLeft(uName) {
    io.sockets.emit('userLeft', { "userName": uName });
}
 
function userNameAvailable(sId, uName) {
  setTimeout(function() {
    console.log('Sending welcome msg to ' + uName + ' at ' + sId);
 
    io.sockets.sockets[sId].emit('welcome', { "userName" : uName, "currentUsers": JSON.stringify(Object.keys(clients)) });
  }, 500);
}
 
function userNameAlreadyInUse(sId, uName) {
  setTimeout(function() {
    io.sockets.sockets[sId].emit('error', { "userNameInUse" : true });
  }, 500);
}
merci pour l'aide