JavaScript with Promises: Managing Asynchronous Code

Asynchronous JavaScript is everywhere, whether you’re usingAjax, AngularJS, Node.js, or WebRTC. This practical guide shows intermediate toadvanced JavaScript developers how Promises can help you manage asynchronouscode effectively—including the inevitable flood of callbacks as your codebasegrows. You’ll learn the inner workings of Promises and ways to avoiddifficulties and missteps when using them.

The ability to asynchronously fetch data and load scripts in the browserbroadens the capabilities of JavaScript applications. But if you don’tunderstand how the async part works, you’ll wind up with unpredictable codethat’s difficult to maintain. This book is ideal whether you’re new to Promisesor want to expand your knowledge of this technology.

• Understand how async JavaScript works by delving into callbacks, the event loop, and threading
• Learn how Promises organize callbacks into discrete steps that are easier to read and maintain
• Examine scenarios you’ll encounter and techniques you can use when writing real-world applications
• Use features in the Bluebird library and jQuery to work with Promises
• Learn how the Promise API handles asynchronous errors
• Explore ECMAScript 6 language features that simplify Promise-related code