Book Image

Microservices with Clojure

By : Anuj Kumar
Book Image

Microservices with Clojure

By: Anuj Kumar

Overview of this book

The microservice architecture is sweeping the world as the de facto pattern with which to design and build scalable, easy-tomaintain web applications. This book will teach you common patterns and practices, and will show you how to apply these using the Clojure programming language. This book will teach you the fundamental concepts of architectural design and RESTful communication, and show you patterns that provide manageable code that is supportable in development and at scale in production. We will provide you with examples of how to put these concepts and patterns into practice with Clojure. This book will explain and illustrate, with practical examples, how teams of all sizes can start solving problems with microservices. You will learn the importance of writing code that is asynchronous and non-blocking and how Pedestal helps us do this. Later, the book explains how to build Reactive microservices in Clojure that adhere to the principles underlying the Reactive Manifesto. We finish off by showing you various ways to monitor, test, and secure your microservices. By the end, you will be fully capable of setting up, modifying, and deploying a microservice with Clojure and Pedestal.
Table of Contents (18 chapters)
Title Page
Dedication
Packt Upsell
Contributors
Preface
Index

Chapter 6. Introduction to Pedestal

"A conceptual framework is a 'frame that works' to put those concepts into practice."

- Paul Hughes

Microservices are implemented using a particular technology stack, which serves a single-bounded context and provides services around it. The services exposed for the external world must be scalable and support direct messaging as well as asynchronous requests. Pedestal (http://pedestal.io/) is one such Clojure framework that fits in well to create reliable and scalable services for microservice-based applications. It also fits in well with the Clojure stack of the Helping Hands application. In this chapter, you will:

  • Learn about the basic concepts of Pedestal
  • Learn how to define Pedestal routes and interceptors
  • Learn how to handle errors with Pedestal interceptors
  • Learn how to publish operational metrics with Pedestal
  • Learn how to use Server-sent Events and Web Sockets with Pedestal