apiVersion: networking.istio.io/v1alpha3 
kind: VirtualService 
metadata:
  name: myservice-vs 
  namespace: mynamespace
spec:
  hosts:
  - "my.host"
  gateways:
  - mygateway
  http:
  - match:
    - uri:
        prefix: /mypath
    route:
     - response:
         code: 200
         body: "this is automatic response"