Angular Reactive Development

Introduction

Background

RxJs originally was developed by Microsoft in Rx.NET. It works on Java and other platforms. The definition is "RxJs is a library for composing asynchronous and event-based programs using observable sequences"

Other approaches

• Callbacks - difficult to use with nested async operations
• Promises - can only handle a single emission and is not cancellable
• Asyc/await - can only handle a single emission and is not cancellable

Why Rxjs

• One - technical for all data e.g. mouse clicks, api calls
• Compositional - with the operators easy to transform and combine
• Watchful - With its push model to notify subscribers
• Laxy - Only executes when subscribed to
• Handles Error - Built in
• Cancellable

Angular already use RxJs in

• Routing
• Reactive Forms
• HttpClient

Reactive Development

This is characterized by

• Quick to react to user - drrrrrr
• Resilient to failure -error checking all the time
• Reactive to state changes

Resources

The demos were at https://github.com/DeborahK/Angular-RxJS