Book Image

JavaScript Design Patterns

By : Hugo Di Francesco
Book Image

JavaScript Design Patterns

By: Hugo Di Francesco

Overview of this book

Unlock the potential of JavaScript design patterns, the foundation for development teams seeking structured and reusable solutions to common software development challenges in this guide to improving code maintainability, scalability, and performance. Discover how these patterns equip businesses with cleaner and more maintainable code, promote team collaboration, reduce errors, and save time and costs. This book provides a comprehensive view of design patterns in modern (ES6+) JavaScript with real-world examples of their deployment in professional settings. You’ll start by learning how to use creational, structural, and behavioral design patterns in idiomatic JavaScript, and then shift focus to the architecture and UI patterns. Here, you’ll learn how to apply patterns for libraries such as React and extend them further to general web frontend and micro frontend approaches. The last section of the book introduces and illustrates sets of performance and security patterns, including messaging and events, asset and JavaScript loading strategies, and asynchronous programming performance patterns. Throughout the book, examples featuring React and Next.js, in addition to JavaScript and Web API examples, will help you choose and implement proven design patterns across diverse web ecosystems, transforming the way you approach development.
Table of Contents (16 chapters)
Part 1:Design Patterns
Part 2:Architecture and UI Patterns
Part 3:Performance and Security Patterns

Asynchronous cancellation and timeouts with AbortController

Another source of bad performance in applications in general is doing work that’s not necessary. In the context of a JavaScript web application, one of the types of “work” that can be unnecessary (and therefore a drain on performance) is having HTTP requests that aren’t required any more. For example, in a photo gallery system or any paginated system, when moving across photos, the request for the previous photo might not have completed before the next one is started. In this case, the previous request data is not necessary any more, as we’re essentially on a completely different page.

In these instances, cancelling the request might be useful.

AbortController is a Web/DOM API that allows us to abort web requests. It’s created using its constructor, new AbortController, and controlling a request (to potentially cancel it) is done with the AbortController().signal value, which...