I don't understand the code in the www.js file

Question

There is a lot of boilerplate code already written for this course that doesn't make sense to me (and its frustrating that there's no explanation of it). 
In the www.js file the http module is required and a server is set up. 
```js
var http = require('http');
/**
 * Get port from environment and store in Express.
 */
var port = normalizePort(process.env.PORT || '3000');
app.set('port', port);
/**
 * Create HTTP server.
 */
var server = http.createServer(app);
/**
 * Listen on provided port, on all network interfaces.
 */
server.listen(port);
``
Why is any of this necessary? With Express you can just useapp.listen(port)`. I don't see why all the above code is necessary.
There is some other stuff that seems unnecessary as well. Like this function:
```js
/**
 * Normalize a port into a number, string, or false.
 */
function normalizePort(val) {
  var port = parseInt(val, 10);
  if (isNaN(port)) {
    // named pipe
    return val;
  }
  if (port >= 0) {
    // port number
    return port;
  }
  return false;
}
```
Why would you need to "normalize" the port number? For what purpose? It's a bit frustrating how this stuff is just written for you with no explanation.

Guil Hernandez · Accepted Answer

Hi there. As mentioned at the beginning of the workshop, I used the Express application generator (https://expressjs.com/en/starter/generator.html) to spin up the Express app. :)

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Michael Cook

Michael Cook

I don't understand the code in the www.js file

1 Answer

Guil Hernandez

Guil Hernandez

Michael Cook

Michael Cook