FormatCloseMessage gets the CloseMessage as a byte sequence.

FormatErrorCode takes a gRPC Code and "encodes" it for use over the websocket bridge.

IsCloseMessage says whether the byte sequence is a close message.

IsgRPCErrorCode says if the input websocket code is a gRPC Error code.

ParseErrorCode takes a websocket error code and "parses" it into a gRPC Code.