Book Image

Spring Microservices

By : Rajesh R V
Book Image

Spring Microservices

By: Rajesh R V

Overview of this book

The Spring Framework is an application framework and inversion of the control container for the Java platform. The framework's core features can be used by any Java application, but there are extensions to build web applications on top of the Java EE platform. This book will help you implement the microservice architecture in Spring Framework, Spring Boot, and Spring Cloud. Written to the latest specifications of Spring, you'll be able to build modern, Internet-scale Java applications in no time. We would start off with the guidelines to implement responsive microservices at scale. We will then deep dive into Spring Boot, Spring Cloud, Docker, Mesos, and Marathon. Next you will understand how Spring Boot is used to deploy autonomous services, server-less by removing the need to have a heavy-weight application server. Later you will learn how to go further by deploying your microservices to Docker and manage it with Mesos. By the end of the book, you'll will gain more clarity on how to implement microservices using Spring Framework and use them in Internet-scale deployments through real-world examples.
Table of Contents (18 chapters)
Spring Microservices
Credits
About the Author
Acknowledgments
About the Reviewer
www.PacktPub.com
Preface
Index

Enabling cross-origin access for microservices


Browsers are generally restricted when client-side web applications running from one origin request data from another origin. Enabling cross-origin access is generally termed as CORS (Cross-Origin Resource Sharing).

This example shows how to enable cross-origin requests. With microservices, as each service runs with its own origin, it will easily get into the issue of a client-side web application consuming data from multiple origins. For instance, a scenario where a browser client accessing Customer from the Customer microservice and Order History from the Order microservices is very common in the microservices world.

Spring Boot provides a simple declarative approach to enabling cross-origin requests. The following example shows how to enable a microservice to enable cross-origin requests:

@RestController
class GreetingController{
  @CrossOrigin
  @RequestMapping("/")
  Greet greet(){
    return new Greet("Hello World!");
  }
}

By default, all...