So I was testing my shiny new gRPC backend deployed with knative and for some reason, the client never reached the backend (both in cluster). The error I got was:
1"error":"rpc error: code = Unknown desc = ",
Which wasn't really helpful. With copious amounts of loggin, I could determin that the requests never actually reached my backend.
At first I suspected the weird way knative sets up the
kubernetes core Service resource,
but looking at the backing Endpoints,
I could see it point to the (theoretically) right thing,
the internal load balancer.
Next I tried grpcurl which to be honest didn't help much as it just reported a similar error. Finally, I remembered that gRPC was just HTTP/2, so plain curl here I come:
1$ curl --resolve authnb.auth.svc:8443:127.0.0.1 -v --http2-prior-knowledge https://authnb.auth.svc:8443
and wouldn't you know it: < HTTP/2 301 pointing to https.
Ah, then I remembered the knative config-network setting
http-protocol: Redirect I had set,
thinking I needed it to redirect external plain http requests.
Setting it to http-protocol: Enabled got me back my grpc connections,
and my external requests still seem to go to https.