示例#1
0
// SetTrailer sets the trailer metadata that will be sent when an RPC returns.
// It may be called at most once from a unary RPC handler. The ctx is the RPC
// handler's Context or one derived from it.
func SetTrailer(ctx context.Context, md metadata.MD) error {
	if md.Len() == 0 {
		return nil
	}
	stream, ok := transport.StreamFromContext(ctx)
	if !ok {
		return fmt.Errorf("grpc: failed to fetch the stream from the context %v", ctx)
	}
	return stream.SetTrailer(md)
}
示例#2
0
// SendHeader sends header metadata. It may be called at most once from a unary
// RPC handler. The ctx is the RPC handler's Context or one derived from it.
func SendHeader(ctx context.Context, md metadata.MD) error {
	if md.Len() == 0 {
		return nil
	}
	stream, ok := transport.StreamFromContext(ctx)
	if !ok {
		return fmt.Errorf("grpc: failed to fetch the stream from the context %v", ctx)
	}
	t := stream.ServerTransport()
	if t == nil {
		grpclog.Fatalf("grpc: SendHeader: %v has no ServerTransport to send header metadata.", stream)
	}
	return t.WriteHeader(stream, md)
}