Book Image

Mastering Node.js

By : Sandro Pasquali
Book Image

Mastering Node.js

By: Sandro Pasquali

Overview of this book

Node.js is a modern development stack focused on providing an easy way to build scalable network software. Backed by a growing number of large companies and a rapidly increasing developer base, Node is revolutionizing the way that software is being built today. Powered by Google's V8 engine and built out of C++ modules, this is a JavaScript environment for the enterprise.Mastering Node.js will take the reader deep into this exciting development environment. Beginning with a comprehensive breakdown of its innovative non-blocking evented design, Node's structure is explained in detail, laying out how its blazingly fast I/O performance simplifies the creation of fast servers, scalable architectures, and responsive web applications.Mastering Node.js takes you through a concise yet thorough tour of Node's innovative evented non-blocking design, showing you how to build professional applications with the help of detailed examples.Learn how to integrate your applications with Facebook and Twitter, Amazon and Google, creating social apps and programs reaching thousands of collaborators on the cloud. See how the Express and Path frameworks make the creation of professional web applications painless. Set up one, two, or an entire server cluster with just a few lines of code, ready to scale as soon as you're ready to launch. Move data seamlessly between databases and file systems, between clients, and across network protocols, using a beautifully designed, consistent, and predictable set of tools.Mastering Node.js contains all of the examples and explanations you'll need to build applications in a short amount of time and at a low cost, running on a scale and speed that would have been nearly impossible just a few years ago.
Table of Contents (20 chapters)
Mastering Node.js
About the Author
About the Reviewers

Chapter 4. Using Node to Access the Filesystem


We have persistent objects — they're called files.

 --Ken Thompson

A file is simply a chunk of data that is persisted, usually, on some hard medium such as a hard drive. Files are normally composed of a sequence of bytes whose encoding maps onto some other pattern, like a sequence of numbers or electrical pulses. A nearly infinite number of encodings are possible, with some common ones being text files, image files, and music files. Files have a fixed length, and to be read their character encoding must be deciphered by some sort of reader, like an MP3 player or a word processor.

When a file is in transit, moving through a cable after it's been siphoned off of some storage device, it is no different than any other data stream running through the wire. Its previous solid state is just a stable blueprint that can be easily and infinitely copied, sliced up, and reworked.

We've seen how evented streams reflect the core design principles informing...