Introducing Deno : A First Look at the Newest JavaScript Runtime

Learn everything there is to know about the new secure runtime for Deno. A proposed replacement for Node.js envisioned and created by the same developer who wrote the first version of Node, Deno is a simple, modern and secure runtime for JavaScript and TypeScript that uses V8 and is built in Rust. This book will cover everything from its inception to the currently available version. You’ll see how to take advantage of the security layer in order to avoid unwanted security holes, and how to use TypeScript to develop your applications without having to manually set up a build process. You'll also learn how to create and use modules without having to depend on a package manager, and much more. Armed with these newly learned concepts, by the time you finish this book, you’ll be ready to build and test your own Deno applications. Whether you’re a brand new developer to the back end with a JavaScript background or a seasoned Node.js developer looking to understand this competing technology, Introducing Deno will put you on the right path. What You'll Learn - Learn why Deno was created and why it is different from Node - Build real applications using Deno and related technologies - Create backend applications with Typescript - Resolve how to live without npm and package.json - Set permissions and default behavior Who This Book Is For Anyone with knowledge of back-end development looking to learn a new way of doing things and those with a basic understanding of JavaScript and Node.js core concepts. Table of Contents......Page 5 About the Author......Page 8 About the Technical Reviewer......Page 9 Acknowledgments......Page 10 Introduction......Page 11 Chapter 1: Why Deno?......Page 12 What problems is it trying to solve?......Page 13 A problematic module system......Page 14 Other minor issues......Page 15 Online playgrounds......Page 16 Deno playground......Page 17 Deno.town......Page 18 Installing Deno on your computer......Page 20 TypeScript as a first-class citizen......Page 21 Security......Page 23 Top-level await......Page 30 Extended and improved standard library......Page 31 No more npm......Page 33 Conclusion......Page 36 What is TypeScript?......Page 37 A quick overview of types......Page 39 The types you already know......Page 40 The new types......Page 41 Working with tuples......Page 42 Enums......Page 43 Taking advantage of the any type......Page 46 A note about nullable types and union types......Page 47 Classes and interfaces......Page 49 Interfaces......Page 50 Optional properties......Page 51 Interfaces for functions......Page 53 Working with classes......Page 54 Visibility modifiers......Page 55 Private modifier......Page 56 Protected modifier......Page 59 Defining accessors......Page 60 Static and abstract classes......Page 62 TypeScript mixins......Page 66 Mixins to the rescue!......Page 68 Conclusion......Page 72 Enforcing security......Page 73 “Everything’s allowed” flag......Page 75 Accessing the environment variables......Page 76 High-resolution time measurement......Page 77 Allowing access to the network interface......Page 78 Allowing plugins to be used......Page 79 Allowing reading from the disk and writing to it......Page 80 Allowing your script to spawn new subprocesses......Page 81 Checking for available permissions......Page 82 Conclusion......Page 87 Dealing with external modules......Page 88 Handling packages......Page 90 Importing from the middle of nowhere......Page 91 What about package versions?......Page 92 Locking your dependencies’ version......Page 97 Going experimental: Using import maps......Page 100 Conclusion......Page 103 The Deno STD: The standard library......Page 104 External modules......Page 108 The official list......Page 109 With the power of blockchain......Page 112 Drash......Page 115 SQL......Page 118 MongoDB......Page 121 Redis......Page 123 Command-line interface......Page 124 Conclusion......Page 127 Deno runner......Page 128 The plan......Page 130 The code......Page 131 Testing your application......Page 136 Chat server......Page 140 A simple client......Page 143 Conclusion......Page 145 Index......Page 146 Learn everything there is to know about the new secure runtime for Deno. A proposed replacement for Node.js envisioned and created by the same developer who wrote the first version of Node, Deno is a simple, modern and secure runtime for JavaScript and TypeScript that uses V8 and is built in Rust. This book will cover everything from its inception to the currently available version. Youll see how to take advantage of the security layer in order to avoid unwanted security holes, and how to use TypeScript to develop your applications without having to manually set up a build process. You'll also learn how to create and use modules without having to depend on a package manager, and much more. Armed with these newly learned concepts, by the time you finish this book, youll be ready to build and test your own Deno applications. Whether youre a brand new developer to the back end with a JavaScript background or a seasoned Node.js developer looking to understand this competing technology, Introducing Deno will put you on the right path. You will: Learn why Deno was created and why it is different from Node ; Build real applications using Deno and related technologies ; Create backend applications with Typescript ; Resolve how to live without npm and package.json ; Set permissions and default behavior