Node is not finding js files included in html

问题:

I'm trying to build a simple chat app using node and socket.io. I am following the tutorial listed here: http://socket.io/get-started/chat/

My issues is that the tutorial has some javascript that is placed in a script tag directly in the html. I would like to move this code into it's own js file.

I made a file called chat.js, that is in the same directory as my index.html and index.js. In my html I put the following code in the header (I also tried right before the ending body tag too)

  <script type="text/javascript" src="chat.js"></script>

However, when I run node index.js in terminal and go to localhost, I get a 400 for chat.js. I've tried placing "/chat.js" as well as "./chat.js" with no luck. All three files are in the same directory.

Any clues to what I am doing wrong will be appreciated.

My index.js

var app = require('express')();
var http = require('http').Server(app);
var io = require('socket.io')(http);

app.get('/', function(req, res){
 res.sendFile(__dirname + '/index.html');
});


io.on('connection', function(socket){
 socket.on('chat message', function(msg){
   io.emit('chat message', msg);
 });
});

http.listen(3000, function(){
 console.log('listening on *:3000');
});

回答1:

node.js does not automatically serve any files like other web servers do. If you want it to send chat.js when the browser requests it, you will have to create a route for it in your node.js code so that the web server will send it.

If you use something like the Express framework, this can be done in perhaps one line of code with app.use(express.static(...)).

Notice how in the demo you linked to, there's a specific route for the / path. You need a similar route for /chat.js or you could use app.use(express.static(...)) to configure the automatic serving of a whole directory of files.

In the future, if you show your actual server code, then we could help more specifically with actual code that fits into your server.

---

Now that you've shown your code, you could add a specific route for /chat.js:

app.get('/chat.js', function(req, res){
    res.sendFile(__dirname + '/chat.js');
});

Or, if you move chat.js to be in a public sub-directory under your app code, then you could serve all files in that directory automatically with this:

app.use(express.static('public'));

When Express gets a request for a route that doesn't have a specific handler, it will check the public sub-directory to see if a file matches the request name. If so, it will automatically serve that file.