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

Adapter in JavaScript

The adapter pattern, similar to the other structural design patterns, focuses on interfaces.

In the adapter pattern’s case, it involves being able to use a new implementation without changing the consumer or the implementation’s interface. The “adapter” takes the new implementation and “adapts” the interface to match what the consumer expects.

We’re not changing the implementation or the consumer; rather, we’re building an adapter to wrap the implementation and plug it into the consumer without changing either.


Let’s start with a simple in-memory database that uses a naive IdGenerator to generate keys for the database entries by encoding the object as a string.

Database has a createEntry method that stores given data using the IdGenerator to generate a key. Database also has a get method to recall entries by ID:

class IdGenerator {
  get(entry) {