Spring Cloud API Gateway routing not working

Question

I have design a micro service prototype using below technologies

1. Eureka Server(Discovery Server)
2. Spring boot (back-end Service)
3. Spring Cloud API GateWay

Above mentioned service are getting up,ApI Gateway and back end services are registered in the Eureka Server

API Gate Way routing Configuration

server.port=8080
eureka.client.serviceUrl.defaultZone = http://localhost:8083/eureka
spring.application.name=ApiGateway
spring.cloud.gateway.discovery.locator.enabled=true
spring.cloud.gateway.discovery.locator.lower-case-service-id=true

spring.cloud.gateway.routes[0].id=service1
spring.cloud.gateway.routes[0].uri=lb://MICROSERVICE1
spring.cloud.gateway.routes[0].predicates[0]=Path=/service1/**

Micro service Configuration

server.port=8081
server.address=127.0.0.1
eureka.client.serviceUrl.defaultZone = http://localhost:8083/eureka
spring.application.name=MicroService1
error.whitelabel.enabled= false

Controller

@RestController
@RequestMapping("/service1")
public class HomeController {
    @GetMapping("/message")
    public String hello() {
        return "response from micro service1";
    }

}

When i send a request to gate way its showing below error

2020-12-16 22:26:09.770 ERROR 16700 --- [ctor-http-nio-3] a.w.r.e.AbstractErrorWebExceptionHandler : [d3334561-1]  500 Server Error for HTTP GET "/service1/message"

java.net.UnknownHostException: failed to resolve 'LAPTOP-KU56B6A8' after 3 queries 
    at io.netty.resolver.dns.DnsResolveContext.finishResolve(DnsResolveContext.java:1013) ~[netty-resolver-dns-4.1.55.Final.jar:4.1.55.Final]
    Suppressed: reactor.core.publisher.FluxOnAssembly$OnAssemblyException: 
Error has been observed at the following site(s):
    |_ checkpoint ⇢ org.springframework.cloud.gateway.filter.WeightCalculatorWebFilter [DefaultWebFilterChain]
    |_ checkpoint ⇢ HTTP GET "/service1/message" [ExceptionHandlingWebHandler]

How we can solve the above issue.

Answer 1

i have modified the API Gate Way routing Configuration like below

spring.cloud.gateway.routes[0].id=service1
spring.cloud.gateway.routes[0].uri=http://localhost:8081/service1/
spring.cloud.gateway.routes[0].predicates[0]=Path=/service1/**

Now is working fine

Answer 2

Add eureka.instance.hostname=localhost in both the microservices instances this will work and not give an error

Answer 3

hello jebji if you still have this problem add spring.cloud.discovery.enabled=true in application.properties

Answer 4

Only Add the following property into your API gateway:

spring.cloud.discovery.enabled=true

Make sure you already added DevTool maven dependency into your API gateway project but if not then restart it.

Answer 5

add flowing property in application.property file of all eruka client microservice and api gateway , i face same issue and resolve doing same activity

spring.cloud.discovery.enabled=true
spring.cloud.gateway.discovery.locator.lower-case-service-id= true
spring.cloud.gateway.discovery.locator.enabled= true
eureka.instance.hostname=localhost

Answer 6

Add spring.cloud.discovery.enabled=true in your application.properties

Answer 7

Add below to both gateway and individual microservice fix the issue

eureka.instance.hostname=localhost
eureka.client.serviceUrl.defaultZone=http://${eureka.instance.hostname}:8010/eureka/

Answer 8

after adding all the above properties then also if you are facing issue then try the below one,

don't use lb://albums_service , but use lb://albums-service .Because URI don‘t support underline.

Answer 9

You can add the following in application.yml file

spring:
  cloud:
    gateway:
      routes:
        - id: test-service
          uri: lb://MICROSERVICE1
          predicates:
            - Path=/microservice1/**
          filters:
            - RewritePath=/microservice1/(?<segment>.*), /$\{segment}

with this it should works.

Like let say if your microservice1 is url is localhost:8081/service1/message then you can define the base path of your microservice1 in api-gateway by setting up the path as i did in above configuration.