Mastering TypeScript E-Book

Nathan Rozentals

• Herausgeber: Packt Publishing
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 732

Veröffentlichungsjahr: 2021

Beschreibung

TypeScript is both a language and a set of tools to generate JavaScript, designed by Anders Hejlsberg at Microsoft to help developers write enterprise-scale JavaScript.

Mastering Typescript is a golden standard for budding and experienced developers. With a structured approach that will get you up and running with Typescript quickly, this book will introduce core concepts, then build on them to help you understand (and apply) the more advanced language features. You’ll learn by doing while acquiring the best programming practices along the way.

This fourth edition also covers a variety of modern JavaScript and TypeScript frameworks, comparing their strengths and weaknesses. You'll explore Angular, React, Vue, RxJs, Express, NodeJS, and others. You'll get up to speed with unit and integration testing, data transformation, serverless technologies, and asynchronous programming. Next, you’ll learn how to integrate with existing JavaScript libraries, control your compiler options, and use decorators and generics.

By the end of the book, you will have built a comprehensive set of web applications, having integrated them into a single cohesive website using micro front-end techniques. This book is about learning the language, understanding when to apply its features, and selecting the framework that fits your real-world project perfectly.

Leseprobe

Mastering TypeScript

Fourth Edition

Build enterprise-ready, modular web applications using TypeScript 4 and modern frameworks

Nathan Rozentals

BIRMINGHAM—MUMBAI

Mastering TypeScript

Fourth Edition

Copyright © 2021 Packt Publishing

All rights reserved. No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, without the prior written permission of the publisher, except in the case of brief quotations embedded in critical articles or reviews.

Every effort has been made in the preparation of this book to ensure the accuracy of the information presented. However, the information contained in this book is sold without warranty, either express or implied. Neither the author, nor Packt Publishing or its dealers and distributors, will be held liable for any damages caused or alleged to have been caused directly or indirectly by this book.

Packt Publishing has endeavored to provide trademark information about all of the companies and products mentioned in this book by the appropriate use of capitals. However, Packt Publishing cannot guarantee the accuracy of this information.

Producers: Aarthi Kumaraswamy, Caitlin Meadows

Acquisition Editor – Peer Reviews: Divya Mudaliar

Project Editor: Janice Gonsalves

Content Development Editor: Alex Patterson

Copy Editor: Safis Editing

Technical Editor: Aniket Shetty

Proofreader: Safis Editing

Indexer: Rekha Nair

Presentation Designer: Ganesh Bhadwalkar

First published: April 2015

Second edition: February 2017

Third edition: February 2019

Fourth edition: April 2021

Production reference: 1210421

Published by Packt Publishing Ltd.

Livery Place

35 Livery Street

Birmingham B3 2PB, UK.

ISBN 978-1-80056-473-2

www.packt.com

Contributors

About the author

Nathan Rozentals has been writing commercial software for over 30 years in C, C++, Java, and C#.

He picked up TypeScript a week after its initial release in October 2012, and was one of the first people to start blogging about TypeScript, discussing early frameworks such as Backbone, Marionette, ExtJS, and AngularJS.

Nathan's TypeScript solutions now control user interfaces in IoT devices, run as stand-alone applications for point-of-sale solutions, provide complex application configuration for websites, and are used for mission-critical server APIs.

When he is not programming, he is thinking about programming. To stop thinking about programming, he goes windsurfing or plays soccer, or just watches the professionals play soccer. They are so much better at it than he is.

I would like to thank my partner, Kathy, for her unwavering support and love over the years. To Ayron and Daya, I am so proud of you both. To Matt, just keep being yourself.To everyone at Vix, thanks for making work such a gratifying experience. Continue to challenge yourselves, continue to question, and continue to learn. You are all so highly talented, and are fantastic people to work with.

About the reviewer

Dan Vanderkam is the author of Effective TypeScript (O'Reilly 2019, now available in Polish!) and a principal software engineer at Sidewalk Labs. He previously worked on open source genome visualizations at Mt. Sinai's Icahn School of Medicine and on search features used by billions of users at Google (try "population of france" or "sunset nyc"). He has a long history of working on open source projects, including the popular dygraphs library and source-map-explorer, a tool for visualizing JavaScript code size. He is also a co-founder of the NYC TypeScript meetup and blogs at effectivetypescript.com. When he's not writing type-safe JavaScript, Dan enjoys playing bridge and rock climbing near his upstate New York home.

Contents

Preface

Who this book is for

What this book covers

To get the most out of this book

Get in touch

Up and Running Quickly

A simple TypeScript IDE

Using npm

Hello TypeScript

Template strings and JavaScript versions

TypeScript project configuration

Watching files for changes

TypeScript basics

Strong typing

Basic types

Inferred typing

Duck typing

Function signatures and void

VS Code IntelliSense

VS Code debugging

Introducing third-party libraries

Declaration files

Summary

Exploring the Type System

any, let, unions, and enums

The any type

Explicit casting

The let keyword

Const values

Union types

Type guards

Type aliases

Enums

String enums

Const enums

More primitive types

Undefined

Null

Conditional expressions

Optional chaining

Nullish coalescing

Null or undefined operands

Definite assignment

Object

Unknown

Never

Never and switch

Object spread

Spread precedence

Spread with arrays

Tuples

Tuple destructuring

Optional tuple elements

Tuples and spread syntax

Object destructuring

Functions

Optional parameters

Default parameters

Rest parameters

Function callbacks

Function signatures as parameters

Function overrides

Literals

Summary

Interfaces, Classes, Inheritance, and Modules

Interfaces

Optional properties

Interfaces are compiled away

Interface naming

Weak types

The in operator

keyof

Classes

The this keyword

Implementing interfaces

Class constructors

Class modifiers

JavaScript private fields

Constructor parameter properties

Readonly

Get and set

Static functions

Static properties

Namespaces

Inheritance

Interface inheritance

Class inheritance

The super function

Function overriding

Protected

Abstract classes

Abstract class methods

instanceof

Interfaces extending classes

Modules

Exporting modules

Importing modules

Module renaming

Multiple exports

Module namespaces

Default exports

Summary

Generics and Advanced Type Inference

Generics

Generic syntax

Multiple generic types

Constraining the type of T

Using the type T

Generic constraints

Generic interfaces

Creating new objects within generics

Advanced type inference

Mapped types

Partial, Readonly, Record, and Pick

Conditional types

Conditional type chaining

Distributed conditional types

Conditional type inference

Type inference from function signatures

Type inference from arrays

Standard conditional types

Summary

Asynchronous Language Features

Callbacks

Promises

Promise syntax

Promise errors

Returning values from Promises

Promise return types

Async and await

Await syntax

Await errors

Await values

Callbacks versus Promises versus async

Summary

Decorators

Decorator overview

Decorator setup

Decorator syntax

Multiple decorators

Types of decorators

Decorator factories

Exploring decorators

Class decorators

Property decorators

Static property decorators

Method decorators

Using method decorators

Parameter decorators

Decorator metadata

Using decorator metadata

Summary

Integration with JavaScript

Declaration files

Global variables

JavaScript code in HTML

Finding declaration files

Writing declaration files

The module keyword

Declaration file typing

Function overloading

Nested namespaces

Classes

Static properties and functions

Abstract classes

Generics

Conditional types

Conditional type inference

Declaration file summary

Integration compiler options

The allowJs and outDir options

Compiling JavaScript

The declaration option

Summary

Strict Compiler Options

Nested configuration

Strict Options

strictNullChecks

strictPropertyInitialization

strictBindCallApply

strictFunctionTypes

no compiler options

noImplicitAny

noUnusedLocals and noUnusedParameters

noImplicitReturns

noFallthroughCasesInSwitch

noImplicitThis

Summary

Using Observables to Transform Data

Introduction to Observables

pipe and map

Combining operators

Avoid swallowing values

Time-based Observables

Observable errors

catchError

Observables returning Observables

mergeMap

concatMap

forkJoin

Observable Subject

Summary

Test-Driven Development

The testing paradigm

Unit, integration, and acceptance tests

Unit tests

Integration tests

Acceptance tests

Unit testing frameworks

Jest

ts-jest

Watch mode

Grouping tests

Forcing and skipping tests

Matchers

Test setup and teardown

Data-driven tests

Jest mocks

Jest spies

Spies returning values

Asynchronous tests

Using done

Using async await

HTML-based tests

DOM events

Protractor

Selenium

Finding page elements

Summary

Angular

Angular setup

Application structure

Angular modules

Angular Material

A shared module

An Angular application

Angular DOM events

Angular EventEmitter

Angular services

Angular Dependency Injection

Child components

Angular forms

Reactive forms

Reactive form templates

Reading form values

Angular unit testing

Unit testing forms

Reacting to domain events

Summary

React

Introduction to React

React setup

JSX

JSX and logic

React props

React event handling

React state

A React application

Application overview

Mechanical keyboard switches

Application components

The CollectionView component

The ItemView component

The DetailView component

The App component

React forms

Summary

Vue

Introduction to Vue

Vue setup

Component structure

Child components and props

Component state

Component events

Computed props, conditionals, and loops

A Vue application

Application overview

Material Design for Bootstrap

App component

ShoppingCart component

ItemView component

CheckoutView component

ItemTotalView component

Summary

Node and Express

Express introduction

Express setup

Express router

Express configuration

An Express application

Express templating

Handlebars configuration

Using templates

Static files

Express forms

Express session data and redirects

Summary

An AWS Serverless API

Serverless setup

AWS Lambda architecture

Installing the SAM CLI

Initializing a SAM application

Generated structure

Deploying a SAM application

Building an API

DynamoDB tables

NoSQL Workbench

Application API endpoints

A Lambda function

Compiling Lambdas

Running Lambdas locally

Lambda path parameters

Processing database records

API summary

Summary

Micro Front-ends

Design concepts

Micro front-end mechanisms

The iframe technique

The JavaScript technique

The Registry technique

What we will use

Communication mechanisms

Domain events

The Event Bus

Building a micro front-end application

The global Event Bus

Building a module

Module typing

React updates

Loading data from an API

React domain events

Vue updates

Vue domain events

Fetching data in Vue

Raising Events

Angular micro front-end

Micro front-end DOM Containers

Rendering the React front-end

Rendering the Vue front-end

Angular domain events

Our micro front-end application

Thoughts on micro front-ends

Summary

Other Books You May Enjoy

Index

Landmarks

Cover

Index