Our control protocol clients use the deprecated grpc.DialContext for connection establishment. The package suggests using grpc.NewClient instead, but this isn't semantically equivalent. More specifically, it cannot be made to block, whereas we specifically want to block when we establish these connections. If we want to migrate, we'll have to write our own wrapper which is equivalent to what grpc.DialContext does.

The deprecated methods will remain supported throughout v1.x of grpc, so this isn't urgent. For now, I've added nolint directives and comments in #5442.