private static SensorMessage[] DecodeBinaryMessage(byte[] rawData)
{
SensorMessage[] readings = null;
if (rawData.Length % SensorMessage.incomingLength != 0)
{
Util.LoggingService.LogInfo($"Binary message recieved over MQTT is invalid. it must consist of sensor readings, " +
$"{SensorMessage.incomingLength} bytes long each. It's length is {rawData.Length}, not divisble by {SensorMessage.incomingLength}"
, Windows.Foundation.Diagnostics.LoggingLevel.Error);
}
else
{
var numberOfReadings = rawData.Length / SensorMessage.incomingLength;
readings = new SensorMessage[numberOfReadings];
//process each reading
for (var i = 0; i < numberOfReadings; i++)
{
readings[i].value = BitConverter.ToSingle(rawData, i * SensorMessage.incomingLength);
readings[i].duration = BitConverter.ToInt32(rawData, i * SensorMessage.incomingLength + 4);
readings[i].SensorTypeID = rawData[i * SensorMessage.incomingLength + 8];
}
}
return(readings);
}
private void MqttMessageRecieved(KeyValuePair <string, MqttMsgPublish> publishEvent)
{
//TODO move this GUID parsing code somewhere appropriate!
Guid clientID;
var rawClientID = publishEvent.Key.Replace(":", string.Empty);
if (Guid.TryParse(rawClientID, out clientID) == false)
{
Debug.WriteLine("recieved message with invalid ClientID");
}
else
{
SensorMessage[] readings;
var message = publishEvent.Value;
if (message.Topic.Contains("reading"))
{
var rawData = message.Message;
if (rawData.Length % SensorMessage.incomingLength != 0)
{
Debug.WriteLine("message recieved over MQTT has incorrect length!");
}
else
{
var numberOfReadings = rawData.Length / SensorMessage.incomingLength;
readings = new SensorMessage[numberOfReadings];
//process each reading
for (var i = 0; i < numberOfReadings; i++)
{
readings[i].value = BitConverter.ToSingle(rawData, i * SensorMessage.incomingLength);
readings[i].duration = BitConverter.ToInt32(rawData, i * SensorMessage.incomingLength + 4);
readings[i].SensorTypeID = rawData[i * SensorMessage.incomingLength + 8];
}
var toWrite = new KeyValuePair <Guid, SensorMessage[]>(clientID, readings);
_datapointsSaver.BufferAndSendReadings(toWrite);
}
}
}
}