version: 4.2.1~4.3.0-M3

There is a bug where GRPCResponseHeadersFilter forces the grpc-status in the trailer to 0.

Assuming that when using gRPC to call a server streaming RPC, the downstream server successfully responds with 2 messages and then encounters an error, responding with a status of 10 (Aborted). The frame that the downstream server responses to the gateway would look like this:

HEADERS FRAME
:status = 200 OK
trailer: grpc-status,grpc-message
content-type = application/grpc
grpc-encoding = identity
grpc-accept-encoding = grpc

DATA FRAME 1
(content)

DATA FRAME 2
(content)

HEADERS FRAME (End stream, =trailer)
grpc-status = 10

However, in the HttpServerOperations#onOutboundComplete() method, the trailerHeaders consumer injected by the GRPCResponseHeadersFilter sets the grpc-status to 0 because the first HEADERS FRAME does not contain a grpc-status value. This seems to be incorrect behavior. Am I misunderstanding something? If it is a bug, what should be done?

Thank you.