Lab 6 - gRPC regex endpoint unimplemented

[davivcgarcia]

One of the gRPCurl commands are not returning the expected output, and looks like there is a misconfiguration in the demo application itself.

$ grpcurl -plaintext -proto grpc.proto -authority bar.com -d '{"name": "grpc-header-a"}' -H 'grpcRegex: grpc-header-a' $NGF_DNS:80 helloworld.Greeter/SayHello
ERROR:
  Code: Unimplemented
  Message: unexpected HTTP status code received from server: 404 (Not Found); transport: received unexpected content-type "text/html"

The related manifest file is NGINX-Gateway-Fabric-Lab/labs/6.grpc/3.grpcroute-header.yaml, and this route is configured here:

  # Matches "headerRegex: grpc-header-[a-z]{1}"
  - matches:
    - headers:
      - name: headerRegex
        value: "grpc-header-[a-z]{1}"
        type: RegularExpression
    backendRefs:
    - name: grpc-infra-backend-v2
      port: 8080

[davivcgarcia]

I've noticed that we are passing the regex match with the wrong header grpcRegex instead of headerRegex which the route is expecting. Fixing the command the result is correct:

$ grpcurl -plaintext -proto grpc.proto -authority bar.com -d '{"name": "grpc-header-a"}' -H 'headerRegex: grpc-header-a' $NGF_DNS:80 helloworld.Greeter/SayHello
{
  "message": "Hello grpc-header-a"
}

Ref.

NGINX-Gateway-Fabric-Lab/labs/6.grpc/README.md

Lines 229 to 232 in c8740f7

	Test the application sending a request with HTTP header `regexHeader: grpc-header-a`
	```code
	grpcurl -plaintext -proto grpc.proto -authority bar.com -d '{"name": "grpc-header-a"}' -H 'grpcRegex: grpc-header-a' ${NGF_IP}:${HTTP_PORT} helloworld.Greeter/SayHello
	```