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
Dedication
Packt Upsell
Contributors
Preface
Free Chapter
1
The Importance of Good Code
Index

Clusters and microservices


In order to make our system be highly available, reliable, scalable, and produce high throughput, we must design a system that is:

  • Resilient/Durable: Able to sustain component failures
  • Elastic: Each service and resource can grow and shrink quickly based on demand

Such systems can be achieved by breaking monolithic applications into many smaller stateless components (following the microservices architecture) and deploying them in a cluster.

Microservices

Instead of having a monolithic code base that caters to many concerns, you can instead break the application down into many services which, when working together, make up the whole application. Each service should:

  • Have one or very few concerns
  • Be de-coupled from other services
  • Be stateless (if possible)

With a monolithic application, all the components must be deployed together as a single unit. if you want to scale your application, you must scale by deploying more instances of the monolith. Furthermore, because there...