private static void WriteUserDataMessage(ref MessagePackWriter writer, UserDataMessage message)
 {
     writer.WriteArrayHeader(3);
     writer.Write(ServiceProtocolConstants.UserDataMessageType);
     writer.Write(message.UserId);
     WritePayloads(ref writer, message.Payloads);
 }
        private static ServiceMessage CreateUserDataMessage(ref MessagePackReader reader, int arrayLength)
        {
            var userId   = ReadString(ref reader, "userId");
            var payloads = ReadPayloads(ref reader);

            var result = new UserDataMessage(userId, payloads);

            if (arrayLength >= 4)
            {
                result.ReadExtensionMembers(ref reader);
            }
            return(result);
        }