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

Moving to microservices


The limitations of a monolithic architecture for Helping Hands can be addressed by separating out the components along with the database as a microservice. These services can then make informed choices about the technology stack and database that suit them well. These services can be developed, changed, and deployed in isolation as per the concepts of a microservices-based architecture. To identify the bounded context for the components of an existing monolithic application, it is recommended to look at the database access pattern and related business logic first, isolate them, and then look at the possibilities to isolate the components further based on business capabilities.

Isolating services by persistence

In the existing monolithic application of Helping Hands, the consumers and providers database tables are accessed by all the core components of the system, as shown in the following diagram. These tables are prime candidates for being wrapped around a service...