Add rewrite support for gRPC

[mrajagopal]

Description

• NGINX Ingress Controller supports a gRPC application using VirtualServer resources as found in grpc-upstream example.
• However the rewrite feature is not supported for GRPC as found in the rewrites example.

Request

Add support for rewriting GRPC requests to upstreams for VS/VSR and Ingress resources

Sample Configuration

NIC VirtualServer:

apiVersion: k8s.nginx.org/v1
kind: VirtualServer
metadata:
  name: grpc-vs
  namespace: $APPNS
spec:
  host: grpcvs.example.com
  tls:
    secret: cafe-secret
  upstreams:
  - name: grpc
    service: grpc-svc
    port: 50051
    type: grpc
  routes:
  - path: /dummy/helloworld.Greeter
    action:
      proxy:
        upstream: grpc
        rewritePath: "/helloworld.Greeter" 

[github-actions]

Hi @mrajagopal thanks for reporting!

Be sure to check out the docs and the Contributing Guidelines while you wait for a human to take a look at this 🙂

Cheers!