Distributed Systems with Node.js

Chapter 1. Why Distributed?

Node.js is a self-contained runtime for running JavaScript code on the server. It provides a JavaScript language engine and dozens of APIs, many of which allow application code to interact with the underlying operating system and the world outside of it. But you probably already knew that.

This chapter takes a high-level look at Node.js, in particular how it relates to this book. It looks at the single-threaded nature of JavaScript, simultaneously one of its greatest strengths and greatest weaknesses, and part of the reason why it’s so important to run Node.js in a distributed manner.

It also contains a small pair of sample applications that are used as a baseline, only to be upgraded numerous times throughout the book. The first iteration of these applications is likely simpler than anything you’ve previously shipped to production.

If you find that you already know the information in these first few sections, then feel free to skip directly to “Sample Applications”.

The JavaScript language is transitioning from being a single-threaded language to being a multithreaded language. The Atomics object, for example, provides mechanisms to coordinate communication across different threads, while instances of SharedArrayBuffer can be written to and read from across threads. That said, as of this writing, multithreaded JavaScript still hasn’t caught on within the community. JavaScript today is multithreaded, but it’s still the nature of the language, and of ...