Book Image

Deno Web Development

By : Alexandre Portela dos Santos
Book Image

Deno Web Development

By: Alexandre Portela dos Santos

Overview of this book

Deno is a JavaScript and TypeScript runtime with secure defaults and a great developer experience. With Deno Web Development, you'll learn all about Deno's primitives, its principles, and how you can use them to build real-world applications. The book is divided into three main sections: an introduction to Deno, building an API from scratch, and testing and deploying a Deno application. The book starts by getting you up to speed with Deno's runtime and the reason why it was developed. You'll explore some of the concepts introduced by Node, why many of them transitioned into Deno, and why new features were introduced. After understanding Deno and why it was created, you will start to experiment with Deno, exploring the toolchain and writing simple scripts and CLI applications. As you progress to the second section, you will create a simple web application and then add more features to it. This application will evolve from a simple 'hello world' API to a web application connected to the database, with users, authentication, and a JavaScript client. In the third section, the book will take you through topics such as dependency management, configuration and testing, finishing with an application deployed in a cloud environment. By the end of this web development book, you will become comfortable with using Deno to create, maintain, and deploy secure and reliable web applications.
Table of Contents (15 chapters)
Section 1: Getting Familiar with Deno
Section 2: Building an Application
Section 3: Testing and Deploying


With this chapter, we've closed the development cycle of the application we've been building. We started small by writing a few simple classes with our business logic, wrote the web server to it, and finished by integrating it with persistence. We finished this section by learning how to test the features we wrote, and that's what we did in this chapter. We decided on going with a few different types of tests, instead of extensively going module by module writing all the tests, as we believe that's where more value is added.

We started with a very simple unit test for the business logic, then moved on to an integration test with multiple classes, and later wrote a test for the web server. These tests can only be written by leveraging the architecture we've created, following dependency injection principles, and trying to keep the code as decoupled as possible.

As the chapter proceeded, we moved on to integration tests, which closely mimic the...