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 10. Event-Driven Patterns for Microservices

"The single biggest problem with communication is the illusion that it has taken place."

- George Bernard Shaw

Microservices address a single bounded context and are deployed independently on one or more physical machines that are distributed across a network. Although they are deployed in isolation, they need to interact with each other to accomplish application-level tasks that may cut across multiple bounded contexts. The choice of communication medium and method has a great impact on the performance and durability of the entire microservice-based architecture. Events are one of the methods of asynchronous communication among microservices to exchange data of interest. Part-1 of the book explains the importance of the observer model and how a message broker (https://en.wikipedia.org/wiki/Message_broker) helps in sending and receiving events in a microservices architecture. In this chapter, you will:

  • Learn about event-driven patterns for...