public async Task <IEventTransmitter> CreateTransmitter(string segmentId, CameraType cameraId)
{
var iotHubOwnerConnectionString = _configurationReader.GetConfigValue <string>("IOTHUB_OWNER_CONNECTIONSTRING", true);
try
{
var policy = Policy
.Handle <TimeoutException>()
.Or <DeviceMessageLockLostException>()
.Or <IotHubCommunicationException>()
.Or <IotHubThrottledException>()
.Or <ServerBusyException>()
.WaitAndRetryAsync(5, retryAttempt =>
TimeSpan.FromSeconds(Math.Pow(2, retryAttempt)),
(exception, span, retryCount, context) => { _logger.Warn(exception, $"Retry {retryCount}/{5} sending to IoT Hub, because of exception {exception}"); });
// Retry maximum 5 times with exponential backoff for the above exceptions
return(await policy.ExecuteAsync(async() =>
{
var iotHubServiceClient = RegistryManager.CreateFromConnectionString(iotHubOwnerConnectionString);
string deviceId = $"{segmentId}-{cameraId}";
var camDevice = await iotHubServiceClient.GetDeviceAsync(deviceId)
?? await iotHubServiceClient.AddDeviceAsync(new Device(deviceId));
var deviceConnectionString =
$"HostName={GetIoTHubUri(iotHubOwnerConnectionString)};DeviceId={deviceId};SharedAccessKey={camDevice.Authentication.SymmetricKey.PrimaryKey}";
if (cameraId == CameraType.Camera1)
{
ConfigurationCache.CacheValue("deviceConnectionString", deviceConnectionString);
}
return new IoTHubTransmitter(deviceConnectionString);
}));
}
catch (Exception e)
{
_logger.Error(e, $"An error occurred when trying read device on IoT Hub: {e.Message}");
throw;
}
}
