Learning Node

Chapter 6. Routing Traffic, Serving Files, and Middleware

Click a link in a web page, and you expect something to happen. That something is typically a page being loaded. However, there’s actually a lot that goes on before that web resource loads—some of which is mostly out of our control (such as packet routing), and some of which is dependent on us having software installed that understands how to respond based on the link’s contents.

Of course, when we use web servers such as Apache, and software such as Drupal, much of the mechanics of serving a file or a resource are handled behind the scenes. However, when we’re creating our own server-side applications in Node and bypassing our usual technology, we have to get more involved in ensuring that the right resource gets delivered at the right time.

This chapter focuses on the technology available to Node developers for providing the very basic routing and middleware functionality we need to ensure that resource A gets delivered to user B correctly and quickly.

Building a Simple Static File Server from Scratch

We have all the functionality we need to build a simple router or to serve static files built directly into Node. But being able to do so and doing so easily are two different things.

When thinking of what’s necessary to build a simple but functional static file server, we might come up with the following set of steps:

1. Create an HTTP server and listen for requests.

2. When a request arrives, parse the request URL to determine ...