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

Creating a microservice for Lookup


The Lookup service is used to search for services by type, geolocation, and availability. It subscribes to the events generated by the ConsumerProviderService, and Order microservices as an Observer and keeps a denormalized dataset that is faster to query for required Services. The Lookup service also adds longitude and latitude for the Services and Consumers that is derived from their address and service area or locality. To get the longitude and latitude from the service area, it depends on an external API. The Lookup service provides the following APIs for consumers to search for a service and also filter the services by type, ratings, and providers:

URI

Description

GET /lookup/?q=query

Filters all the services based on the specified query.

GET /lookup/?q=query&type=type

Filters all the services of a given type based on the specified query.

GET /lookup/geo/?tl=40.73,-74.1&br=40.01,-71.12

Looks up the service by the given latitude-longitude set for...