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

Request/reply patterns


Dealing with a messaging system often means using a one-way asynchronous communication; publish/subscribe is a perfect example.

One-way communications can give us great advantages in terms of parallelism and efficiency, but alone they are not able to solve all our integration and communication problems. Sometimes, a good old request/reply pattern might just be the perfect tool for the job. Therefore, in all those situations where an asynchronous one-way channel is all that we have, it's important to know how to build an abstraction that allows us to exchange messages in a request/reply fashion. That's exactly what we are going to learn next.

Correlation identifier

The first request/reply pattern we are going to learn is called correlation identifier and it represents the basic block for building a request/reply abstraction on top of a one-way channel.

The pattern consists of marking each request with an identifier, which is then attached to the response by the receiver...