Wilson - Node.js the right way practical, server-side JavaScript that scales

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This was a surprisingly difficult book to write, and I couldnt have done it without a lot of help.Im especially thankful for my editor, Jackie Carteryour thoughtful feedback made this book what it is today.

Id also sincerely like to thank the whole team at The Pragmatic Bookshelf.Thanks for your kind patience while I figured out how to write this book.And thanks to the entire team, who worked so hard to polish this book and find all of my mistakes.

Id like to thank all my reviewers.Your keen observations have helped make this book even more technically correct (the best kind of correct).In no particular order:

And I want to thank my wonderful family, too.Ruthy, you are my inspiration; with your quiet perseverance, you can achieve anything.Emma and Jimmy, even though youre both growing up too fast, I cant wait to see all the great things youll do.

For anyone I missed, I hope youll accept my apologies.Any omissions were certainly not intentional.

Two big shifts are happening right now in the practice of writing software, and Node.js is at the forefront of both.

First, software is becoming increasingly asynchronous.Whether youre waiting for a Big Data job, interacting with end users, or simply responding to an API call, chances are youll need asynchronous programming techniques.

Second, JavaScript has quietly become the worlds standard virtual machinein web browsers, modern NoSQL databases, and now on the server as well.

Node.js is right at the intersection of these trends, and its ready to take off in a big way.

In March of 2010, I gave a lightning talk titled Full-Stack JavaScript at the NoSQL Boston conference.Back then, and even more so now, I knew that using JavaScript for every layer of the application stack was not only possible, but a great way to reduce software complexity.

The Right Way in this books title refers to both the process of learning Node and the practice of writing Node.

As for any growing technology, there are lots of resources available for learning Node.js.Many are intently focused on serving up web resources.The web is great, but its not enough, and its not the whole story of Node.

Ruby is more than Rails, and Python is more than Django.Node.js is more than serving web content, and this book treats it that way.

Node.js the Right Way teaches you the core concepts youll need to be an effective Node.js programmer, no matter what kinds of programs you need to write.

One thing I love about JavaScript is that there are seven ways to do anything.Theres breathing room, where developers can explore and experiment and find better approaches to everything.

The community of Node developers, conventions in Node.js development, and even the semantics of the JavaScript language itself are all rapidly evolving.With eyes to the near future, the code examples and recommendations in this book reflect current best practices and standards.

This book is for developers who want to learn how to write asynchronous JavaScript for the server using Node.js.Some prior JavaScript experience will help, but you dont have to be an expert.

Chapter 1, , introduces the Node.js event loop, explaining how it empowers Node to be highly parallel and single-threaded at the same time.This chapter also outlines the five aspects of Node.js development that frame each subsequent chapter and has some brief instructions on getting Node installed on your machine.

The remaining chapters each deal with a specific practical programming area.

In Chapter 2, , well get our first look at writing Node.js programs.If youve done any server-side programming in the past, chances are youve had to access a file system along the way.Well start in this familiar domain, using Nodes file-system tools to create asynchronous, nonblocking file utilities.Youll use Nodes ubiquitous