Service Discover using Spring cloud kubernetes

Question

I am doing a POC on simple microservices architecture using typical Spring cloud stack but instead of Eureka server, service discovery is to be made using spring-cloud-kubernetes which is not working.

The whole POC is here - https://github.com/dhananjay12/spring-microservices-using-spring-kubernetes

Gateway as a edge server and 2 downstream services- user-service and contact-us-service.

The k8 setup is in k8s folder.

The downstream services have following dependencies:

<dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-kubernetes</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>

application.yml

server:
  port: 8100

management:
  endpoints:
    web:
      exposure:
        include: '*'


spring:
  cloud:
    kubernetes:
      enabled: true
      reload:
        enabled: true
eureka:
  client:
    enabled: false

bootstrap.yml:

spring:
  application:
    name: user-service

and annotation of @EnableDiscoveryClient in the main class.

The gateway service has too relevant kubernetes dependencies:

<dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-kubernetes</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-ribbon</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-kubernetes-ribbon</artifactId>
        </dependency>

application.yml

server:
  port: 8050

spring:
  application:
    name: gateway
  cloud:
    kubernetes:
      enabled: true
      reload:
        enabled: true
    gateway:
      discovery:
        locator:
          lowerCaseServiceId: true
          enabled: true

eureka:
  client:
    enabled: false


logging:
  level:
    root: DEBUG
    org.springframework.gateway: TRACE
    org.springframework.cloud.gateway: TRACE
    org.springframework.cloud.loadbalancer: TRACE


management:
  endpoints:
    web:
      exposure:
        include: '*'

bootstrap.yml

spring:
  application:
    name: gateway

and annotation of @EnableDiscoveryClient in the main class.

Please see the deployment and service yaml here - https://github.com/dhananjay12/spring-microservices-using-spring-kubernetes/tree/master/k8s

I am able to get to gateway but it is not routing to downstream service like user-service:

For example - /user-service/users/getPublicMailingAddress

gives Whitable error page

and the logs in gateway shows:


2019-07-07 06:40:30.017 TRACE 1 --- [or-http-epoll-2] o.s.c.g.h.p.RoutePredicateFactory : Pattern "[/my-nginx-nginx-ingress-controller/**]" does not match against value "/user-service/users/getPublicMailingAddress"

Please edit the question to add the `kubectl describe` for the services and pods and `kubectl logs` so we can see the startup of each service. — Andy Shinn, Jul 08 '19 at 00:22
How this part was configured?: `public String getContactUsDetails() { List serviceList = client.getInstances("user-service"); if (serviceList != null && serviceList.size() > 0) { System.out.println("Sevice list===>" + serviceList.size()); String result = rest.getForObject(serviceList.get(0) .getUri() + "/users/getPublicMailingAddress", String.class); return "Contact Address ==> " + result;` — Mark, Jul 08 '19 at 16:49

score 1 · Accepted Answer · answered Jul 17 '19 at 10:08

Spring Cloud Kubernetes requires access to the Kubernetes API in order to be able to retrieve a list of addresses for pods running for a single service. If you use Kubernetes, you should just execute the following command:

kubectl create clusterrolebinding admin --clusterrole=cluster-admin --serviceaccount=default:default

score 0 · Answer 2 · answered Jul 08 '19 at 17:53

Is your cluster running in RBAC mode? If so you'll probably have to create a service account, give it the proper cluster role and configure your deployments to use that specific service account.

In case you don't want to expose every privilege to the pods, following access rights/resources should suffice:

apiVersion: rbac.authorization.k8s.io/v1beta1
kind: ClusterRole
metadata:
  name: custom-role
rules:
- apiGroups: [""]
  resources:
  - endpoints
  - namespaces
  - pods
  - services
  verbs:
  - get
  - watch
  - list

Service Discover using Spring cloud kubernetes

2 Answers2