Book Image

Node.js Design Patterns - Second Edition

By : Joel Purra, Luciano Mammino, Mario Casciaro
Book Image

Node.js Design Patterns - Second Edition

By: Joel Purra, Luciano Mammino, Mario Casciaro

Overview of this book

Node.js is a massively popular software platform that lets you use JavaScript to easily create scalable server-side applications. It allows you to create efficient code, enabling a more sustainable way of writing software made of only one language across the full stack, along with extreme levels of reusability, pragmatism, simplicity, and collaboration. Node.js is revolutionizing the web and the way people and companies create their software. In this book, we will take you on a journey across various ideas and components, and the challenges you would commonly encounter while designing and developing software using the Node.js platform. You will also discover the "Node.js way" of dealing with design and coding decisions. The book kicks off by exploring the basics of Node.js describing it's asynchronous single-threaded architecture and the main design patterns. It then shows you how to master the asynchronous control flow patterns,and the stream component and it culminates into a detailed list of Node.js implementations of the most common design patterns as well as some specific design patterns that are exclusive to the Node.js world.Lastly, it dives into more advanced concepts such as Universal Javascript, and scalability' and it's meant to conclude the journey by giving the reader all the necessary concepts to be able to build an enterprise grade application using Node.js.
Table of Contents (20 chapters)
Node.js Design Patterns - Second Edition
Credits
About the Authors
Acknowledgments
About the Author
Acknowledgments
About the Reviewers
www.PacktPub.com
Preface

Chapter 2. Node.js Essential Patterns

Embracing the asynchronous nature of Node.js is not trivial at all, especially if coming from a language such as PHP where it is not usual to deal with asynchronous code.

In synchronous programming, we are used to the concept of imagining code as a series of consecutive computing steps defined to solve a specific problem. Every operation is blocking, which means that only when an operation is completed is it possible to execute the next one. This approach makes the code easy to understand and debug.

Instead, in asynchronous programming, some operations, such as reading a file or performing a network request, can be executed as an operation in the background. When an asynchronous operation is invoked, the next one is executed immediately, even if the previous operation has not finished yet. The operations pending in the background can complete at any time, and the whole application should be programmed to react in the proper way when an asynchronous call...