Book Image

Building Microservices with Spring

By : Dinesh Rajput, Rajesh R V
Book Image

Building Microservices with Spring

By: Dinesh Rajput, Rajesh R V

Overview of this book

Getting Started with Spring Microservices begins with an overview of the Spring Framework 5.0, its design patterns, and its guidelines that enable you to implement responsive microservices at scale. You will learn how to use GoF patterns in application design. You will understand the dependency injection pattern, which is the main principle behind the decoupling process of the Spring Framework and makes it easier to manage your code. Then, you will learn how to use proxy patterns in aspect-oriented programming and remoting. Moving on, you will understand the JDBC template patterns and their use in abstracting database access. After understanding the basics, you will move on to more advanced topics, such as reactive streams and concurrency. Written to the latest specifications of Spring that focuses on Reactive Programming, the Learning Path teaches you how to build modern, internet-scale Java applications in no time. Next, you will understand how Spring Boot is used to deploying serverless autonomous services by removing the need to have a heavyweight application server. You’ll also explore ways to deploy your microservices to Docker and managing them with Mesos. By the end of this Learning Path, you will have the clarity and confidence for implementing microservices using Spring Framework. This Learning Path includes content from the following Packt products: • Spring 5 Microservices by Rajesh R V • Spring 5 Design Patterns by Dinesh Rajput
Table of Contents (22 chapters)
Title Page
Copyright
About Packt
Contributors
Preface
Index

Zuul proxy as the API Gateway


In most microservices implementations, internal microservices endpoints are not exposed outside. They are kept as private services. A set of public services will be exposed to the clients using an API Gateway. There are many reasons to do this, some of which are listed as follows:

  • Only a selected set of microservices are required by the clients.
  • If there are client-specific policies to be applied, it is easy to apply them in a single place rather than in multiple places. An example of such a scenario is the cross-origin access policy.
  • It is hard to implement client-specific transformations at the service endpoint.
  • If there is data aggregation required, especially to avoid multiple client calls in a bandwidth restricted environment, then a gateway is required in the middle.

Zuul is a simple gateway service or edge service, which well suits such situations. Zuul also came from the Netflix family of microservices products. Unlike many enterprise API gateway products...