node.js app can't find socket.io

Question

I installed socket.io in the app directory (along with express) and in the index.html file I link to it this way:

<script src="http://localhost:8080/node_modules/socket.io/lib/socket.io.js"></script>

I get a 404 on this request. I double-checked the link and it's fine. the node.js app runs on port 8080 and I have no idea why it doesn't work

UPDATE: Apparently it is something to with Express. When not using it I don't have that problem and socket.io works fine. This is he setup of my server file:

var express = require('express'),
    http = require('http');

var app = express();
var server = http.createServer(app);
var io = require('socket.io').listen(server);

app.listen(8000);

and this is the front-end:

<script src="/socket.io/socket.io.js"></script>
<script src="js/vendor/jquery-1.8.3.min.js"></script>
<script>
  var socket = io.connect('http://localhost:8000');

Also, I switched the jQuery from google CDN to local and it doesn't find it too

Answer 1

Make sure you've made socket.io listening to external connections in your back-end. Basically socket.io has inside method of providing your socket.io.js file, so you should place your require ('socket.io').listen(app) before defining any routes to your app.

The correct url is :

<script src="/socket.io/socket.io.js"></script>

as randunel said.

So, your configuration should look like this :

UPDATED for express 3.x :

var express = require('express'),
    http = require('http');

var app = express();
var server = http.createServer(app).listen(8000);

require('socket.io').listen(server);  // Your app passed to socket.io

Server-side

<script src="http://localhost:8000/socket.io/socket.io.js"></script>

Answer 2

Don't use that whole path, it does not correspond to your project's directory structure. Just use

<script src="http://localhost:8080/socket.io/socket.io.js"></script>

By the way, make sure that socket.io is also listening on 8080, not just the other services in your project.

Answer 3

尝试把你的JS文件中http://localhost:8080/javascripts/socket.io.js ，基本上你的JavaScript目录public文件夹中。

Answer 4

The way is the one from randunel.

<script src="http://localhost:8080/socket.io/socket.io.js"></script>

If you link the file directly, you can get a "Welcome to socket.io" message instead of the file. There's also a CDN socket.io.js file available to link, but it's outdated and will not work fine on new projects, so it's not recommended.