how we can make possible the communication of services inside the Kubernetes via envoy proxy. I have two microservices designed in spring boot, one is called the server which has simple GetResponse by providing data to the client which is the second microservice. The server get response is;

@GetMapping("/server")
public String serverDemo(){
	return  "This message body sent from the server";
}

This request will be catch by the client microservice which simple return it. the client microservice is;

@Autowired
private RestTemplate restTemplate;

@Value("${URL}")
private String url;


@GetMapping("/client")
public String clientDemo() {
    try {
        System.out.println("Inside the client request");
        System.out.println("The url is: " + url);
        ResponseEntity<String> forEntity = restTemplate.getForEntity(url, String.class);
        System.out.println("output is: " + forEntity);
        return forEntity.toString();
    }catch (Exception err){
        System.out.println(err.getMessage());
        return err.getMessage();
    }
}

@GetMapping("/clientgreet")
public String clientGreet() {
    System.out.println("Inside the client greet");
    return "Welcome to the greeting section...";
}

Here the URL is the environment variable which is provided in the kubernetes file by containing the server getresponse url. The server-k8s.yml Kubernetes file is;

apiVersion: apps/v1
kind: Deployment
metadata:
  name: server-deployment
  labels:
    app: server
spec:
  replicas: 1
  selector:
    matchLabels:
      app: server
  template:
    metadata:
      labels:
        app: server
        version: v1
    spec:
      containers:
        - name: server
          image: 'feezankhattak2208/istioserver:istioserver'
          imagePullPolicy: IfNotPresent
          resources:
            limits:
              memory: 128Mi
              cpu: 500m
          ports:
            - containerPort: 8001

---

apiVersion: v1
kind: Service
metadata:
  name: server-svc
  labels:
    app: server
spec:
  selector:
    app: server
  ports:
    - port: 8001
      protocol: TCP
      name:  http
      targetPort: 8001

While the client-k8s.yml Kubernetes file is;

apiVersion: apps/v1
kind: Deployment
metadata:
  name: client-deployment
  labels:
    app: client
spec:
  replicas: 1
  selector:
    matchLabels:
      app: client
  template:
    metadata:
      labels:
        app: client
        version: v1
    spec:
      containers:
        - name: client
          image: 'feezankhattak2208/istioclient:istioclient'
          imagePullPolicy: IfNotPresent
          resources:
            limits:
              memory: 128Mi
              cpu: 500m
          ports:
            - containerPort: 8002
          env:
            - name: URL
              value: 'http://server-svc:8001/server'

---

apiVersion: v1
kind: Service
metadata:
  name: client-svc
  labels:
    app: client
spec:
  type: LoadBalancer
  selector:
    app: client
  ports:
    - protocol: TCP
      name:  http
      port: 8002
      targetPort: 8002
      nodePort: 30002

The client is accessible outside by hitting the following URL http://localhost:8002/clientgreet but when I hit its /client it says;

404 Not Found: "{"timestamp":"2022-02-09T13:29:53.109+00:00","status":404,"error":"Not Found","path":"/server"}"

the url http://localhost:8002/clientgreet works right but the url http://localhost:8002/client fails.

I change the env values to http://server-svc/server, http://localhost:8002/server but it fails too.

Thanks in advance for the help :)