Book Image

Mastering Spring Cloud

By : Piotr Mińkowski
Book Image

Mastering Spring Cloud

By: Piotr Mińkowski

Overview of this book

Developing, deploying, and operating cloud applications should be as easy as local applications. This should be the governing principle behind any cloud platform, library, or tool. Spring Cloud–an open-source library–makes it easy to develop JVM applications for the cloud. In this book, you will be introduced to Spring Cloud and will master its features from the application developer's point of view. This book begins by introducing you to microservices for Spring and the available feature set in Spring Cloud. You will learn to configure the Spring Cloud server and run the Eureka server to enable service registration and discovery. Then you will learn about techniques related to load balancing and circuit breaking and utilize all features of the Feign client. The book now delves into advanced topics where you will learn to implement distributed tracing solutions for Spring Cloud and build message-driven microservice architectures. Before running an application on Docker container s, you will master testing and securing techniques with Spring Cloud.
Table of Contents (22 chapters)
Title Page
Copyright and Credits
Packt Upsell

Load balancing with Ribbon

The main concept around Ribbon is a named client. That's why we may call other services using their names instead of the full address with hostname and port, without connecting to a service discovery. In that case, the list of addresses should be provided in the Ribbon configuration settings inside the application.yml file.

Enabling communication between microservices using the Ribbon client

Let's proceed with the example. It consists of four independent microservices. Some of them may call endpoints exposed by the others. The application source code is available here:

In this example, we will try to develop a simple order system where customers may buy products. If a customer decides to confirm a selected list of products to buy, the POST request is sent to the order-service. It is processed by the Order prepare(@RequestBody Order order) {...} method inside REST controller. This method is responsible for order...