Implementing a virtual hosting paradigm

If we wish to host multiple sites on one server, we can do so with virtual hosting. Virtual hosting is a way to uniquely handle multiple domain names according to their name. The technique is surprisingly simple: we just look at the incoming Host header and respond accordingly. In this task, we're going to implement simple name based virtual hosting for static sites.

Getting ready

We'll create a folder called sites, with localhost-site and nodecookbook as subdirectories. In localhost-site/index.html we'll write the following:

<b> This is localhost </b>

And in nodecookbook/index.html we'll add the following code:

<h1>Welcome to the Node Cookbook Site!</h1>

For local testing, we'll want to configure our system with some extra host names so we can point different domains to our server. To do this, we edit /etc/hosts on Linux and Max OS X, or %SystemRoot%\system32\drivers\etc\hosts for Windows systems.

At the top of the file it maps...