This tutorial is the continuation of Spring Cloud: Exploring Zuul Gateway tutorial. In this tutorial, we will be exploring the functionality of filters provided by Zuul.

As discussed earlier Zuul provides various filters which we can use for request validation or processing. Let’s say if you have an incoming request and if you want to check whether the user is authenticated or not, you can use Zuul pre-filter for this.  If your request is processed and if you want to encrypt the response you can use Zuul post filter. The major upside of Zuul filter is, you can manage all of your filters at a centralized location.

Zuul has provision to create following four types of filter.

1. pre filters run before the request is routed.
2. route filters can handle the actual routing of the request.
3. post filters run after the request has been routed.
4. error filters run if an error occurs while handling the request.

This is a quick tutorial for Spring cloud Zuul component. In this tutorial, we will explore Zuul functionality and will create a gateway to our Spring cloud environment using Zuul.

What is Zuul?

Zuul is a gateway component in Spring cloud ecosystem. It provides access to the services present in our Spring cloud from services/applications which are outside of our environment.

Zuul creates a single entry point for our application which we can use from the outside world. In our environment, we might have 100’s of services running, each one serving a special purpose. Now if we want to access those services via another network or from the internet, then exposing those 100 services will not be a great idea.

In such cases, Zuul comes handy. It provides us with a single proxy to access those services. Apart from that Zuul also provides request filters. We can use those to check/process each and every request before it hits the actual service.

TL;DR You can download whole project by clicking following link.

This tutorial is a continuation of Spring Cloud: Adding Hystrix Circuit Breaker. In the previous tutorial, we had an overview of Hystrix circuit breaker and we have implemented the same in our producer application. Now in this tutorial, we will see it in action.

This is a quick tutorial on Hystrix circuit break. This tutorial gives an overview of Hystrix circuit breaker component present in Spring Cloud and how we can implement it in our project.

What is Hystrix Circuit Breaker?

Hystrix circuit breaker follows the circuit breaker pattern. In layman terms, you can visualize it similar to your electrical circuit break present at your home. Firstly, Hystrix allows us to define fallback methods. Secondly, Whenever a method starts throwing errors due to any reason and it has a fallback method defined, Hystrix will invoke the fallback method rather than invoking the main method. That is it will isolate the erroneous method for time being.

TL;DR You can download whole project by clicking following link.

In this tutorial, we will be creating a spring boot application and we will be adding a fallback method using Hystrix.

Feign occupies an odd spot in 2026: the Netflix incarnation is long dead, but its community successor — Spring Cloud OpenFeign — is alive, widely deployed, and in “feature-complete” maintenance, while Spring’s own HTTP interface clients are the stated future. This rewrite of my 2020 Feign tutorial shows declarative REST clients on Spring Boot 3.x the modern way: OpenFeign with Eureka and Spring Cloud LoadBalancer, Resilience4j fallbacks, and an honest section on when to pick @HttpExchange instead.

Continue reading Spring Cloud OpenFeign on Spring Boot 3.x: Declarative REST Clients with Eureka and Resilience4j →

This is a quick tutorial for creating a REST API client using Spring Cloud Ribbon component. For this tutorial, you will need a running Eureka server and a Eureka client application. In case if you do not have Eureka server or a Eureka client application, check out my previous posts which explain how to setup eureka server and how to develop a eureka client application.

What is Ribbon?

In short, Ribbon is a load balancer. Let’s say you have a service which is used by 1000’s of customers. In that case, you may have multiple instances of service running on multiple servers for load balancing purpose. Now if you want to consume that service in another service, you should not hard code its URL. Because that will always point to only one service and will defeat the purpose of load balancing.

Ribbon helps us to solve this issue. Ribbon on backend talks with Eureka server and will get all instances of services and try to distribute the load across instances.

TL;DR You can download whole project by clicking following link.

To give you a brief idea about the project… We will have a producer which we will be launching multiple times. We will be creating a consumer with Ribbon which will consume the service exposed by the producer. At the same time, it will take care of load balancing as well.

Eureka is the survivor of the Spring Cloud Netflix stack. While Hystrix, Zuul, and Ribbon were removed from Spring Cloud years ago, Eureka server and client are still actively maintained and ship in every current release train. This post — a complete rewrite of my 2020 Eureka series — builds a working setup on Spring Boot 3.x: a Eureka server, a registered student service, and a second service that discovers and calls it through Spring Cloud LoadBalancer, with none of the deprecated pieces.

Continue reading Service Discovery with Eureka in Spring Boot 3.x: Server, Client, and Calling Services →