Book Image

TypeScript 4 Design Patterns and Best Practices

By : Theofanis Despoudis
Book Image

TypeScript 4 Design Patterns and Best Practices

By: Theofanis Despoudis

Overview of this book

Design patterns are critical armor for every developer to build maintainable apps. TypeScript 4 Design Patterns and Best Practices is a one-stop guide to help you learn design patterns and practices to develop scalable TypeScript applications. It will also serve as handy documentation for future maintainers. This book takes a hands-on approach to help you get up and running with the implementation of TypeScript design patterns and associated methodologies for writing testable code. You'll start by exploring the practical aspects of TypeScript 4 and its new features. The book will then take you through the traditional gang of four (GOF) design patterns in their classic and alternative form and show you how to use them in real-world development projects. Once you've got to grips with traditional design patterns, you'll advance to learning about their functional programming and reactive programming counterparts and how to couple them to deliver better and more idiomatic TypeScript code. By the end of this TypeScript book, you'll be able to efficiently recognize when and how to use the right design patterns in any practical use case and gain the confidence to work on scalable and maintainable TypeScript projects of any size.
Table of Contents (14 chapters)
1
Section 1: Getting Started with TypeScript 4
4
Section 2: Core Design Patterns and Concepts
8
Section 3: Advanced Concepts and Best Practices

The asynchronous propagation of changes

In practical terms, Reactive programming represents a paradigm where we use declarative code to describe asynchronous communications and events. This means that when we submit a request or a message to a channel, it will be processed or accepted at a later time. As we obtain data as part of the response that we try to build, we send it back asynchronously. It is then the responsibility of the consumer to react based on those changes. The communication format needs to be established beforehand, whether you send the data in chunks or whether you send it back in a single response.

Next, we describe a few of the most popular communication techniques and patterns that you can use when developing Reactive programming systems.

The pull pattern

With the Pull pattern, the consumer of the data needs to proactively query the source for updates and react based on any new information. This means that they have to poll the producer periodically for...