Book Image

Node.js Design Patterns - Third Edition

By : Mario Casciaro, Luciano Mammino
5 (1)
Book Image

Node.js Design Patterns - Third Edition

5 (1)
By: Mario Casciaro, Luciano Mammino

Overview of this book

In this book, we will show you how to implement a series of best practices and design patterns to help you create efficient and robust Node.js applications with ease. We kick off by exploring the basics of Node.js, analyzing its asynchronous event driven architecture and its fundamental design patterns. We then show you how to build asynchronous control flow patterns with callbacks, promises and async/await. Next, we dive into Node.js streams, unveiling their power and showing you how to use them at their full capacity. Following streams is an analysis of different creational, structural, and behavioral design patterns that take full advantage of JavaScript and Node.js. Lastly, the book dives into more advanced concepts such as Universal JavaScript, scalability and messaging patterns to help you build enterprise-grade distributed applications. Throughout the book, you’ll see Node.js in action with the help of several real-life examples leveraging technologies such as LevelDB, Redis, RabbitMQ, ZeroMQ, and many others. They will be used to demonstrate a pattern or technique, but they will also give you a great introduction to the Node.js ecosystem and its set of solutions.

Related Content you might be interested in

Current Title:

Small book image
Node.js Design Patterns - Third Edition
Mario Casciaro | Luciano Mammino
Jul, 2020 | 664 pages
Small book image
Mastering Node.js
Kevin Faaborg | Sandro Pasquali
Dec, 2017 | 498 pages
Small book image
Hands-On JavaScript High Performance
Justin Scherer
Feb, 2020 | 376 pages
Small book image
Node Cookbook
Bethany Griggs
Nov, 2020 | 512 pages
Table of Contents (16 chapters)
Preface
Preface
What you need for this book
Who this book is for
What this book covers
To get the most out of this book
Get in touch
1
The Node.js Platform
The Node.js Platform
The Node.js philosophy
How Node.js works
JavaScript in Node.js
Summary
Free Chapter
2
The Module System
The Module System
The need for modules
Module systems in JavaScript and Node.js
The module system and its patterns
CommonJS modules
Module definition patterns
ESM: ECMAScript modules
ESM and CommonJS differences and interoperability
Summary
3
Callbacks and Events
Callbacks and Events
The Callback pattern
The Observer pattern
Summary
Exercises
4
Asynchronous Control Flow Patterns with Callbacks
Asynchronous Control Flow Patterns with Callbacks
The difficulties of asynchronous programming
Callback best practices and control flow patterns
The async library
Summary
Exercises
5
Asynchronous Control Flow Patterns with Promises and Async/Await
Asynchronous Control Flow Patterns with Promises and Async/Await
Promises
Async/await
The problem with infinite recursive promise resolution chains
Summary
Exercises
6
Coding with Streams
Coding with Streams
Discovering the importance of streams
Getting started with streams
Asynchronous control flow patterns with streams
Piping patterns
Summary
Exercises
7
Creational Design Patterns
Creational Design Patterns
Factory
Builder
Revealing Constructor
Singleton
Wiring modules
Summary
Exercises
8
Structural Design Patterns
Structural Design Patterns
Proxy
Decorator
The line between proxy and decorator
Adapter
Summary
Exercises
9
Behavioral Design Patterns
Behavioral Design Patterns
Strategy
State
Template
Iterator
Middleware
Command
Summary
Exercises
10
Universal JavaScript for Web Applications
Universal JavaScript for Web Applications
Sharing code with the browser
Fundamentals of cross-platform development
A brief introduction to React
Creating a Universal JavaScript app
Summary
Exercises
11
Advanced Recipes
Advanced Recipes
Dealing with asynchronously initialized components
Asynchronous request batching and caching
Canceling asynchronous operations
Running CPU-bound tasks
Summary
Exercises
12
Scalability and Architectural Patterns
Scalability and Architectural Patterns
An introduction to application scaling
Cloning and load balancing
Decomposing complex applications
Summary
Exercises
13
Messaging and Integration Patterns
Messaging and Integration Patterns
Fundamentals of a messaging system
Publish/Subscribe pattern
Task distribution patterns
Request/Reply patterns
Summary
Exercises
14
Other Books You May Enjoy
Other Books You May Enjoy
15
Index
Index

Asynchronous control flow patterns with streams

Going through the examples that we have presented so far, it should be clear that streams can be useful not only to handle I/O, but also as an elegant programming pattern that can be used to process any kind of data. But the advantages do not end at its simple appearance; streams can also be leveraged to turn "asynchronous control flow" into "flow control," as we will see in this section.

Sequential execution

By default, streams will handle data in sequence. For example, the _transform() function of a Transform stream will never be invoked with the next chunk of data until the previous invocation completes by calling callback(). This is an important property of streams, crucial for processing each chunk in the right order, but it can also be exploited to turn streams into an elegant alternative to the traditional control flow patterns.

Some code is always better than too much explanation, so let's...

Previous Section
End of Section 4
Next Section