I have been trying my hand at node.js and socket.io, and following a tutorial. I keep getting an error from an application i am building. This is my server.js file:
var http = require('http');
var fs = require('fs');
var path = require('path');
var mime = require('mime');
var cache = {};
var chatServer = require('./lib/chat_server.js');
chatServer.listen(server);
//file doesn't exist
function send404(response) {
response.writeHead(404, {'Content-Type': 'text/plain'});
response.write('Error 404: resource not found.');
response.end();
}
//handles serving file data
function sendFile(response, filePath, fileContents) {
response.writeHead(
200,
{"content-type": mime.lookup(path.basename(filePath))}
);
response.end(fileContents);
}
//cache static files to memory
function serveStatic(response, cache, absPath) {
if (cache[absPath]) {
sendFile(response, absPath, cache[absPath]);
} else {
fs.exists(absPath, function(exists) {
if (exists) {
fs.readFile(absPath, function(err, data) {
if (err) {
send404(response);
}
else {
cache[absPath] = data;
sendFile(response, absPath, data);
}
});
}
else {
send404(response);
}
});
}
}
var server = http.createServer(function(request, response) {
var filePath = false;
if (request.url == '/') {
filePath = 'public/index.html';
}
else {
filePath = 'public' + request.url;
}
var absPath = './' + filePath;
serveStatic(response, cache, absPath);
});
server.listen(3001, function() {
console.log("Server listening on port 3001.");
});
This is my index.html file:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">
<title>Chat</title>
<meta name="description" content="An interactive chat application using websockets.">
<link rel="stylesheet" href="/stylesheets/style.css">
</head>
<body>
<div id='content'>
<div id='room'></div>
<div id='room-list'></div>
<div id='messages'></div>
<form id='send-form'>
<input id='send-message' />
<input id='send-button' type='submit' value='Send'/>
<div id='help'>
Chat commands:
<ul>
<li>Change nickname: <code>/nick [username]</code></li>
<li>Join/create room: <code>/join [room name]</code></li>
</ul>
</div>
</form>
</div>
<script src="[localserver here]:3001/socket.io/socket.io.js" type="text/javascript"></script>
<script src="/javascripts/jquery-1.8.3.min.js" type="text/javascript"></script>
<script src="/javascripts/chat.js" type="text/javascript"></script>
<script src="/javascripts/chat_ui.js" type="text/javascript"></script>
</body>
</html>
Upon loading "[localserver here]:3001" from the browser, the index page appears with the ensuing CSS. But when i try an event, like sending a message, i get this error:
Error 404: resource not found.
I right-clicked and inspected element from my Chrome browser and got this two messages:
Failed to load resource: the server responded with a status of 404 (Not Found) "[localserver here]:3001/socket.io/socket.io.js"
Uncaught ReferenceError: io is not defined "[localserver here]:3001/javascripts/chat_ui.js:26"
This is line 26 from my chat_ui.js file:
var socket = io.connect('[localserver here]:3001');
$(document).ready(function() {
var chatApp = new Chat(socket);
socket.on('nameResult', function(result) {
var message;
if (result.success) {
message = 'You are now known as ' + result.name + '.';
} else {
message = result.message;
}
$('#messages').append(divSystemContentElement(message));
});
socket.on('joinResult', function(result) {
$('#room').text(result.room);
$('#messages').append(divSystemContentElement('Room changed.'));
});
socket.on('message', function (message) {
var newElement = $('<div></div>').text(message.text);
$('#messages').append(newElement);
});
socket.on('rooms', function(rooms) {
$('#room-list').empty();
for(var room in rooms) {
room = room.substring(1, room.length);
if (room != '') {
$('#room-list').append(divEscapedContentElement(room));
}
}
$('#room-list div').click(function() {
chatApp.processCommand('/join ' + $(this).text());
$('#send-message').focus();
});
});
setInterval(function() {
socket.emit('rooms');
}, 1000);
$('#send-message').focus();
$('#send-form').submit(function() {
processUserInput(chatApp, socket);
return false;
});
})
I have tried all sorts. Initially line 26 was var socket = io.connect(); and i changed it to the one above. I also changed the directory of socket.io.js in the index.html file from:
to
...as i thought this was the problem, but it is still giving me the same error.
Please how do i resolve this?
(PS - I am using Brackets as my IDE for node.js development. Also, i used "[localserver]" to indicate the localhost)
