Book Image

JavaScript Concurrency

By : Adam Boduch
Book Image

JavaScript Concurrency

By: Adam Boduch

Overview of this book

Concurrent programming may sound abstract and complex, but it helps to deliver a better user experience. With single threaded JavaScript, applications lack dynamism. This means that when JavaScript code is running, nothing else can happen. The DOM can’t update, which means the UI freezes. In a world where users expect speed and responsiveness – in all senses of the word – this is something no developer can afford. Fortunately, JavaScript has evolved to adopt concurrent capabilities – one of the reasons why it is still at the forefront of modern web development. This book helps you dive into concurrent JavaScript, and demonstrates how to apply its core principles and key techniques and tools to a range of complex development challenges. Built around the three core principles of concurrency – parallelism, synchronization, and conservation – you’ll learn everything you need to unlock a more efficient and dynamic JavaScript, to lay the foundations of even better user experiences. Throughout the book you’ll learn how to put these principles into action by using a range of development approaches. Covering everything from JavaScript promises, web workers, generators and functional programming techniques, everything you learn will have a real impact on the performance of your applications. You’ll also learn how to move between client and server, for a more frictionless and fully realized approach to development. With further guidance on concurrent programming with Node.js, JavaScript Concurrency is committed to making you a better web developer. The best developers know that great design is about more than the UI – with concurrency, you can be confident every your project will be expertly designed to guarantee its dynamism and power.
Table of Contents (17 chapters)
JavaScript Concurrency
About the Author
About the Reviewer

Building the API

We'll begin the implementation with the NodeJS back-end. This is where we'll build the necessary API endpoints. We don't necessarily have to start with building the back-end first. In fact, a lot of the time, the UI design drives the API design. Different development shops have different approaches; we're doing the back-end first for no particular reason.

We'll start by implementing the basic HTTP serving and request routing mechanisms. Then, we'll look at using coroutines as handler functions. We'll wrap up the section with a look at how each of our handler functions are implemented.

The HTTP server and routing

We're not going to use anything more than the core http Node module for handling HTTP requests. In a real application, where we're more likely to use a web framework that takes care of a lot of boilerplate code for us, we would probably have a router component at our disposal. Our requirements are very similar to what we'd find in these routers, so we'll just roll our...