Change appProtocol of gRPC from http to grpc or http2

[imaisos]

Preflight Checklist

• I agree to follow the Code of Conduct that this project adheres to.
• I have searched the issue tracker for an issue that matches the one I want to file, without success.
• I am not looking for support or already pursued the available support channels without success.

Chart

dex

Version

0.20.0

Expected Behavior

Change helm template to modify appProtocol on grpc port from http to grpc so that health checks work correctly with istio or allow to modify appProtocol on values.

Actual Behavior

The current template does not allow to change the appProtocol and a health check between two different pods does not work correctly if istio is enabled and grpc's appProtocol is http.

Steps To Reproduce

1. Enable istio
2. Deploy dex helm chart
3. Try to make a health check between two pods to the grpc port with appProtocol: http.

Additional Information

No response

Values

[aliksax]

Hello.
When will it be implemented?
I encountered the issue when I attempted to expose the Dex GRPC API via the gateway API using HTTPRoute or GRPCRoute.
Because appProtocol is set to HTTP, but the backend service must accept HTTP2.

I was able to expose the DEX API with an ingress controller. Thanks.

[aleicher]

@aliksax I did run into the same issue when exposing the dex admin GRPC interface in an istio servicemesh. Provided a small update to the chart in the PR, to always set the appProtocol to grpc.