Feign client : Load balancer does not have available server for client

Question

I'm working on a microservice architecture, I'm using Feign client to make a rest call to another microservice. I using spring boot version 2.1.3.RELEASE and spring cloud: Greenwich.SR3. here is my feign client:

Proxy interface:

import java.util.List;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import relevebancaire.workflow.activiti.model.ReleveBancaire;

@FeignClient(name = "activiti-workflow")
    public interface ActivitiWorkflowProxy {


  @GetMapping("/relevebancaire/{relevebancaireId}")
 public ReleveBancaire getReleveBancaireById(@PathVariable Long relevebancaireId);


}

Feing controller:

import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
import relevebancaire.workflow.activiti.model.ReleveBancaire;
import relevebancaire.workflow.activiti.proxy.ActivitiWorkflowProxy;

@RestController
public class ActivitiController {

  @Autowired
  ActivitiWorkflowProxy activitiWorkflowProxy;


  @GetMapping("/relevebancaire/{relevebancaireId}")
  ResponseEntity<ReleveBancaire> getReleveBancaireById(@PathVariable Long relevebancaireId){
  return new ResponseEntity<>(activitiWorkflowProxy.getReleveBancaireById(relevebancaireId), HttpStatus.OK);

  }


}

Spring boot application:

@SpringBootApplication
@EnableFeignClients
@EnableEurekaClient
@EnableDiscoveryClient
public class ActivitiWorkflowBootloader {

  public static void main(String[] args) {
    SpringApplication.run(ActivitiWorkflowBootloader.class, args);
  }

}

Application.properties:

ribbon.eureka.enabled=true
server.port=8081
spring.application.name=activiti-workflow
activiti-workflow.ribbon.listOfServers = http://localhost:8081

Error:

2022-04-21 05:23:31.626 ERROR 3956 --- [nio-8081-exec-3] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is java.lang.RuntimeException: com.netflix.client.ClientException: Load balancer does not have available server for client: activiti-workflow] with root cause

com.netflix.client.ClientException: Load balancer does not have available server for client: activiti-workflow
    at com.netflix.loadbalancer.LoadBalancerContext.getServerFromLoadBalancer(LoadBalancerContext.java:483) ~[ribbon-loadbalancer-2.3.0.jar:2.3.0]
    at com.netflix.loadbalancer.reactive.LoadBalancerCommand$1.call(LoadBalancerCommand.java:184) ~[ribbon-loadbalancer-2.3.0.jar:2.3.0]
    at com.netflix.loadbalancer.reactive.LoadBalancerCommand$1.call(LoadBalancerCommand.java:180) ~[ribbon-loadbalancer-2.3.0.jar:2.3.0]
    at rx.Observable.unsafeSubscribe(Observable.java:10327) ~[rxjava-1.3.8.jar:1.3.8]

I've searched all over stackoverflow and implemented a lot of solutions out there and nothing solved this. I even used all the solutions on this question: Load balancer does not have available server for client but nothing. Any help please.

Answer 1

If you have Eureka on the classpath, by default the Ribbon client inside Feign uses the Eureka server list, and not the one from the <feign-client>.ribbon.listOfServers property.

To change this you either have to turn off Eureka support in Ribbon by setting ribbon.eureka.enabled=false or use the programmatic server list configuration, e.g.

@Bean
public ServerList<Server> ribbonServerList() {
    return new ConfigurationBasedServerList(); 
    // or new StaticServerList<>(new Server("activiti-workflow", 80));
}

Reference: https://github.com/spring-cloud/spring-cloud-netflix/issues/564