Book Image

Mastering Spring 5.0

By : In28Minutes Official
Book Image

Mastering Spring 5.0

By: In28Minutes Official

Overview of this book

Spring 5.0 is due to arrive with a myriad of new and exciting features that will change the way we’ve used the framework so far. This book will show you this evolution—from solving the problems of testable applications to building distributed applications on the cloud. The book begins with an insight into the new features in Spring 5.0 and shows you how to build an application using Spring MVC. You will realize how application architectures have evolved from monoliths to those built around microservices. You will then get a thorough understanding of how to build and extend microservices using Spring Boot. You will also understand how to build and deploy Cloud-Native microservices with Spring Cloud. The advanced features of Spring Boot will be illustrated through powerful examples. We will be introduced to a JVM language that’s quickly gaining popularity - Kotlin. Also, we will discuss how to set up a Kotlin project in Eclipse. By the end of the book, you will be equipped with the knowledge and best practices required to develop microservices with the Spring Framework.
Table of Contents (20 chapters)
Title Page
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Spring Cloud Bus


Spring Cloud Bus makes it seamless to connect microservices to lightweight message brokers, such as Kafka and RabbitMQ.

The need for Spring Cloud Bus

Consider an example of making a configuration change in a microservice. Let's assume that there are five instances of Microservice A running in production. We would need to make an emergency configuration change. For example, let's make a change in localconfig-repo/microservice-a.properties:

    application.message=Message From Default Local 
      Git Repository Changed

For Microservice A to pick up this configuration change, we need to invoke a POST request on http://localhost:8080/refresh. The following command can be executed at command prompt to send a POST request:

curl -X POST http://localhost:8080/refresh

You will see the configuration change reflected at http://localhost:8080/message. The following is the response from the service:

    {"message":"Message From Default Local Git Repository Changed"}

We have five instances of...