9.7. Using HTTP2 and gRPC

Procedure

1. Add the serverless.openshift.io/default-enable-http2=true annotation to the KnativeServing Custom Resource:

   $ oc annotate knativeserving <your_knative_CR> -n knative-serving serverless.openshift.io/default-enable-http2=true

2. After the annotation is added, you can verify that the appProtocol value of the Kourier service is h2c:

   $ oc get svc -n knative-serving-ingress kourier -o jsonpath="{.spec.ports[0].appProtocol}"

   Example output

   h2c

3. Now you can use the gRPC framework over the HTTP/2 protocol for external traffic, for example:

   import "google.golang.org/grpc"
   
   grpc.Dial(
      YOUR_URL, 

   1

   
      grpc.WithTransportCredentials(insecure.NewCredentials())), 

   2

   
   )

   1

   Your ksvc URL.

   2

   Your certificate.