public static async Task<KustoOperations> GetClientAsync()
{
await semaphoreSlim.WaitAsync();
try
{
return instance ?? (instance = CreateInstance());
}
finally
{
semaphoreSlim.Release();
}
}
public async Task SaveDeviceTwinOperationAsync(string eventData, ILogger log, string tenant, string deviceId, string operationType, TelemetryTimestamp timeStamp, EventHubHelper eventHubHelper)
{
try
{
string deviceTwin = eventData;
Twin twin = null;
JObject deviceTwinJson = new JObject();
deviceTwinJson.Add(DeviceTelemetryKeyConstants.DeviceId, deviceId.ToString());
deviceTwinJson.Add(DeviceTelemetryKeyConstants.TimeStamp, timeStamp.DateTime);
deviceTwinJson.Add(DeviceTelemetryKeyConstants.TimeReceived, timeStamp.EpochTimestamp);
deviceTwinJson.Add(DeviceTelemetryKeyConstants.EventOpType, operationType);
deviceTwinJson.Add(DeviceTelemetryKeyConstants.IsDeleted, false);
if (operationType.ToString().Equals("createDeviceIdentity"))
{
deviceTwinJson.Add(DeviceTelemetryKeyConstants.DeviceCreatedDate, timeStamp.DateTime);
try
{
twin = await TenantConnectionHelper.GetRegistry(Convert.ToString(tenant)).GetTwinAsync(deviceId.ToString());
deviceTwin = twin.ToJson();
}
catch (Exception e)
{
log.LogError($"Unable to fetch DeviceId: {deviceId} device twin from iothub of tenant: {tenant}.", e);
}
}
else
{
JObject previousTwin = null;
KustoOperations kustoClient = await KustoOperations.GetClientAsync();
string kustoQuery = $"DeviceTwin | where DeviceId == \"{deviceId}\" | summarize arg_max(TimeStamp, *) by DeviceId | where IsDeleted == false";
var deviceTwinList = await kustoClient.QueryAsync <DeviceTwinModel>($"IoT-{tenant}", kustoQuery, null);
DeviceTwinModel preDeviceTwin = deviceTwinList.FirstOrDefault();
if (preDeviceTwin != null)
{
previousTwin = preDeviceTwin.Twin;
deviceTwinJson.Add(DeviceTelemetryKeyConstants.DeviceCreatedDate, preDeviceTwin.DeviceCreatedDate);
}
else
{
deviceTwinJson.Add(DeviceTelemetryKeyConstants.DeviceCreatedDate, default(DateTime)); // Set Device Created Date to Default if twin is not present in storage.
try
{
twin = await TenantConnectionHelper.GetRegistry(Convert.ToString(tenant)).GetTwinAsync(deviceId.ToString());
if (twin != null)
{
previousTwin = JObject.Parse(twin.ToJson());
}
}
catch (Exception e)
{
log.LogError($"Unable to fetch DeviceId: {deviceId} device twin from iothub of tenant: {tenant}.", e);
}
}
switch (operationType)
{
case "deviceConnected":
if (preDeviceTwin != null)
{
previousTwin["connectionState"] = "Connected";
previousTwin["lastActivityTime"] = timeStamp.DateTime;
}
break;
case "deviceDisconnected":
if (preDeviceTwin != null)
{
previousTwin["connectionState"] = "Disconnected";
previousTwin["lastActivityTime"] = timeStamp.DateTime;
}
break;
case "updateTwin":
if (preDeviceTwin != null)
{
JObject twinFragment = JObject.Parse(eventData);
previousTwin = previousTwin.UpdateJson(twinFragment);
}
else
{
previousTwin = JObject.Parse(eventData);
}
break;
case "deleteDeviceIdentity":
deviceTwinJson[DeviceTelemetryKeyConstants.IsDeleted] = true;
break;
default:
break;
}
deviceTwin = previousTwin?.ToString();
}
deviceTwinJson.Add(DeviceTelemetryKeyConstants.Data, deviceTwin);
// Save the Device Twin Data to EventHub for further processing
var byteMessage = Encoding.UTF8.GetBytes(JsonConvert.SerializeObject(deviceTwinJson));
var eventDeviceTwinData = new Azure.Messaging.EventHubs.EventData(byteMessage);
eventDeviceTwinData.Properties.Add("deviceid", deviceId.ToString());
await eventHubHelper.SendMessageToEventHub($"{tenant}-devicetwin", new Azure.Messaging.EventHubs.EventData[] { eventDeviceTwinData });
}
catch (Exception exception)
{
throw new ApplicationException($"Save Device Twin operation failed: {exception}, operation type: {operationType}, tenant: {tenant}, deviceId {deviceId}");
}
}