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

Writing E2E tests with Gherkin, Cucumber, and Selenium

Now, we are ready to integrate with tools that can mimic user interaction with a browser. For our first test, let's test something very simple—a user will type in a valid email, but their password is too short. In this case, we want to assert that the Register button will be disabled.

Like our backend E2E tests, we will be writing our test cases in Gherkin, and using Cucumber to run our scenarios. So, let's add these as development dependencies:

$ yarn add cucumber babel-register --dev

Then, we need to create feature files and step definition files. For our first scenario, I have opted to group the features and steps in the following structure:

$ tree --dirsfirst spec
└── cucumber
    ├── features
    │   └── users
    │       └── register
    │           └── main.feature
    └── steps
        ├── assertions
        │   └── index.js
        ├── interactions
        │   ├── input.js
        │   └── navigation.js
        └── index.js