Book Image

Angular for Enterprise-Ready Web Applications - Second Edition

By : Doguhan Uluca
Book Image

Angular for Enterprise-Ready Web Applications - Second Edition

By: Doguhan Uluca

Overview of this book

This second edition of Angular for Enterprise-Ready Web Applications is updated with in-depth coverage of the evergreen Angular platform. You’ll start by mastering Angular programming fundamentals. Using the Kanban method and GitHub tools, you’ll build great-looking apps with Angular Material and also leverage reactive programming patterns with RxJS, discover the flux pattern with NgRx, become familiar with automated testing, utilize continuous integration using CircleCI, and deploy your app to the cloud using Vercel Now and GCloud. You will then learn how to design and develop line-of-business apps using router-first architecture with observable data anchors, demonstrated through oft-used recipes like master/detail views, and data tables with pagination and forms. Next, you’ll discover robust authentication and authorization design demonstrated via integration with Firebase, API documentation using Swagger, and API implementation using the MEAN stack. Finally, you will learn about DevOps using Docker, build a highly available cloud infrastructure on AWS, capture user behavior with Google Analytics, and perform load testing. By the end of the book, you’ll be familiar with the entire gamut of modern web development and full-stack architecture, learning patterns and practices to be successful as an individual developer on the web or as a team in the enterprise.
Table of Contents (19 chapters)
15
Another Book You May Enjoy
16
Index

Null guarding in Angular

In JavaScript, the undefined and null values are a persistent issue that must be proactively dealt with every step of the way. This is especially critical when dealing with external APIs and other libraries. If we don't deal with undefined and null values, then your app may present badly rendered views, console errors, issues with business logic, or even a crash of your entire app.

There are multiple strategies to guard against null values in Angular:

  • Property initialization
  • The safe navigation operator, ?.
  • Null guarding with *ngIf

You may use one or more of these strategies. However, in the next few sections I demonstrate why the *ngIf strategy is the optimal one to use.

To simulate the scenario of getting an empty response from the server, go ahead and comment out the getCurrentWeather call in ngOnInit of CurrentWeatherComponent:

src/app/current-weather/current-weather.component.ts
ngOnInit(): void...