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

The async library


If we take a look for a moment at every control flow pattern we have analyzed so far, we can see that they could be used as a base to build reusable and more generic solutions. For example, we could wrap the unlimited parallel execution algorithm into a function which accepts a list of tasks, runs them in parallel, and invokes the given callback when all of them are complete. This way of wrapping control flow algorithms into reusable functions can lead to a more declarative and expressive way to define asynchronous control flows, and that's exactly what async (https://npmjs.org/package/async) does. The async library is a very popular solution, in Node.js and JavaScript in general, to deal with asynchronous code. It offers a set of functions that greatly simplify the execution of a set of tasks in different configurations and it also provides useful helpers for dealing with collections asynchronously. Even though there are several other libraries with a similar goal, async...