HTTP response in Express

Now that we have covered the basics of HTTP response in general, let's find out if it works in Express.

By now, we already know how a simple HTTP response can be generated in Express—by setting up a route and a handler for it:

app.get('/', function(req, res) {
  res.send('welcome');
});

Let's examine the response for this response.

Note

Express can send an HTTP response using one of its response methods: res.send(), res.json(), res.jsonp(), res.sendfile(), res.download(), res.render(), or res.redirect(). If none of them is called, the request will be left hanging till the connection times out.

If more than one response methods are specified in a route handler, only the first method will take effect, the rest will generate non-fatal, run-time errors.

Start the app, load the homepage, and look at the response headers using a browser-debugging tool:

HTTP/1.1 200 OK
X-Powered-By: Express
Content-Type: text/html; charset=utf-8
Content-Length: 7
Date: Sat, 09 Mar 2013 15:55:24...