Book Image

Node.js Web Development - Fourth Edition

By : David Herron
Book Image

Node.js Web Development - Fourth Edition

By: David Herron

Overview of this book

Node.js is a server-side JavaScript platform using an event-driven, non-blocking I/O model allowing users to build fast and scalable data-intensive applications running in real time. This book gives you an excellent starting point, bringing you straight to the heart of developing web applications with Node.js. You will progress from a rudimentary knowledge of JavaScript and server-side development to being able to create, maintain, deploy and test your own Node.js application.You will understand the importance of transitioning to functions that return Promise objects, and the difference between fs, fs/promises and fs-extra. With this book you'll learn how to use the HTTP Server and Client objects, data storage with both SQL and MongoDB databases, real-time applications with Socket.IO, mobile-first theming with Bootstrap, microservice deployment with Docker, authenticating against third-party services using OAuth, and use some well known tools to beef up security of Express 4.16 applications.
Table of Contents (14 chapters)

Real-time updates on the Notes homepage


The goal we're working towards is for the Notes home page to automatically update the list of notes, as notes are edited or deleted. What we've done so far is to restructure the application startup so that Socket.IO is initialized in the Notes application. There's no change of behavior yet, except that it will crash due to a missing function.

The approach is for the Notes model classes to send messages whenever a note is created, updated, or deleted. In the router classes, we'll listen to those messages, then send a list of note titles to all browsers attached to the Notes application. 

Where the Notes model so far has been a passive repository of documents, it now needs to emit events to any interested parties. This is the listener pattern and, in theory, there will be code that is interested in knowing when notes are created, edited, or destroyed. At the moment, we'll use that knowledge to update the Notes home page, but there are many potential other...