/// <summary>
/// Connect
/// Connect to Azure IoT Hub ans start the send and receive loops
/// </summary>
/// <returns></returns>
public bool Connect()
{
try
{
// Create Azure IoT Hub Client and open messaging channel
deviceClient = DeviceClient.CreateFromConnectionString(this.ConnectionString);
deviceClient.OpenAsync();
IsConnected = true;
// Create send and receive tasks
CancellationToken ct = TokenSource.Token;
Task.Factory.StartNew(async()=> {
while (true)
{
if (SendTelemetryData)
{
// Create message to be sent
D2CMessage[] dataToSend = new D2CMessage[Sensors.Count];
int index = 0;
foreach (KeyValuePair<string, D2CMessage> sensor in Sensors)
{
// Update the values that
sensor.Value.displayname = DisplayName;
sensor.Value.location = Location;
sensor.Value.timecreated = DateTime.UtcNow.ToString("o");
dataToSend[index++] = sensor.Value;
}
// Send message
sendDeviceTelemetryData(dataToSend);
}
await Task.Delay(SendTelemetryFreq);
if (ct.IsCancellationRequested)
{
// Cancel was called
Debug.WriteLine("Sending task canceled");
break;
}
}
}, ct);
Task.Factory.StartNew(async() =>
{
while (true)
{
// Receive message from Cloud (for now this is a pull because only HTTP is available for UWP applications)
Message message = await deviceClient.ReceiveAsync();
if (message != null)
{
try
{
// Read message and deserialize
C2DMessage command = DeSerialize(message.GetBytes());
// Invoke message received callback
OnReceivedMessage(new ReceivedMessageEventArgs(command));
// We received the message, indicate IoTHub we treated it
await deviceClient.CompleteAsync(message);
}
catch
{
// Something went wrong. Indicate the backend that we coudn't accept the message
await deviceClient.RejectAsync(message);
}
}
if (ct.IsCancellationRequested)
{
// Cancel was called
Debug.WriteLine("Receiving task canceled");
break;
}
}
}, ct);
}
catch (Exception e)
{
Debug.WriteLine("Error while trying to connect to IoT Hub: " + e.Message);
deviceClient = null;
return false;
}
return true;
}
public Task RejectAsync(string lockToken)
{
return(_deviceClient.RejectAsync(lockToken));
}