Book Image

Building Enterprise JavaScript Applications

By : Daniel Li
Book Image

Building Enterprise JavaScript Applications

By: Daniel Li

Overview of this book

With the over-abundance of tools in the JavaScript ecosystem, it's easy to feel lost. Build tools, package managers, loaders, bundlers, linters, compilers, transpilers, typecheckers - how do you make sense of it all? In this book, we will build a simple API and React application from scratch. We begin by setting up our development environment using Git, yarn, Babel, and ESLint. Then, we will use Express, Elasticsearch and JSON Web Tokens (JWTs) to build a stateless API service. For the front-end, we will use React, Redux, and Webpack. A central theme in the book is maintaining code quality. As such, we will enforce a Test-Driven Development (TDD) process using Selenium, Cucumber, Mocha, Sinon, and Istanbul. As we progress through the book, the focus will shift towards automation and infrastructure. You will learn to work with Continuous Integration (CI) servers like Jenkins, deploying services inside Docker containers, and run them on Kubernetes. By following this book, you would gain the skills needed to build robust, production-ready applications.
Table of Contents (26 chapters)
Title Page
Copyright and Credits
Packt Upsell
Free Chapter
The Importance of Good Code

Migrating our API to Express

There are two ways to install Express: directly in the code itself or through the express-generator application generator tool. The express-generator tool installs the express CLI, which we can use to generate an application skeleton from. However, we won't be using that because it's mainly meant for client-facing applications, while we are just trying to build a server-side API at the moment. Instead, we'll add the express package directly into our code.

First, add the package into our project:

$ yarn add express

Now open up your src/index.js file, and replace our import of the http module with the express package. Also replace the current http.createServer and server.listen calls with express and app.listen. What was previously this:

import http from 'http';
const server = http.createServer(requestHandler);

Would now be this:

import express from 'express';
const app = express();

To help us know...