Section 2 – Developing our backend API

Chapter 4, Setting Up Development Tools, explains the different module formats in JavaScript, including CommonJS and ES6 modules. We'll also be setting up our local environment with tools such as nvm, yarn, Babel, nodemon, and ESLint.

Chapter 5, Writing End-to-End Tests, helps you practice TDD by teaching you how to write end-to-end (E2E) tests using Cucumber and Gherkin. We'll also migrate our API to Express as part of the refactoring step.

Chapter 6, Storing Data in Elasticsearch, continues our TDD journey as we persist our application data onto Elasticsearch, a NoSQL document store and search engine. Toward the end of the chapter, we'll also write some Bash scripts to streamline our testing process.

Chapter 7, Modularizing Our Code, will break our application down into smaller modules. We will also integrate JSON Schema and Ajv in our implementation of the validation module.

Chapter 8, Writing Unit/Integration Tests, will teach you how to use Mocha to write unit and integration tests. In order to isolate our unit tests from external dependencies, we will refactor our code to follow a Dependency Injection (DI) pattern, and use Sinon's spies and stubs to mock those dependencies. Lastly, we will use Istanbul/nyc to provide test coverage reports, which will help us identify errors and improve the quality of our code.

Chapter 9, Designing Our API, begins with a discussion of representational state transfer (REST)—what it is, and what it is not. Then, we will examine different types of consistency – Common, Local, Transversal, Domain, and Perennial – and see how they contribute to providing an intuitive developer experience.

Chapter 10, Deploying Your Application on a VPS, provides step-by-step instructions on how to deploy our API on a Virtual Private Server (VPS). You'll learn how to buy a domain, configure Domain Name System (DNS) records, set up NGINX as a reverse proxy, and keep your Node.js process alive with PM2.

Chapter 11, Continuous Integration, implements a Continuous Integration (CI) pipeline into our development process. We begin by using a hosted platform called Travis, before deploying our own self-hosted Jenkins CI server.

Chapter 12, Security: Authentication and Authorization, introduces you to concepts underpinning authorization and password-, session-, and token-based authentication. These include cryptographic hashing, salts, and JSON Web Tokens (JWTs).

Chapter 13, Documenting Our API, completes the development of our API by documenting it using Swagger. You will learn how to write OpenAPI-compliant specifications in YAML, and visualize them using Swagger UI.