private static async Task SendTelemetry(CancellationTokenSource cts) {
while (!cts.Token.IsCancellationRequested) {
// Flag used when we need to pause telemetry send due to needdd reindexing
bool breakForReindexing = false;
RecEdgeMessage recEdgeMessage = new RecEdgeMessage() {
deviceId = ioTEdgeDeviceId,
observations = new List<Observation>()
};
// Iterate over all previously indexed sensors
foreach(KeyValuePair<HueDeviceDescription, HueClientDescription> sensorDescriptionEntry in hueSensors)
{
// Extract sensor and client metadata
HueDeviceDescription sensorDescription = sensorDescriptionEntry.Key;
HueClientDescription clientDescription = sensorDescriptionEntry.Value;
LocalHueClient client = clientDescription.client;
// Query for current sensor state
Sensor sensor = await client.GetSensorAsync(sensorDescription.id);
// Verify that the indexed sensor is still correct; if not,
// some change to the underlying Hue environment has occured;
// if so, return and trigger reindexing
if (sensor.UniqueId != sensorDescription.uniqueId) {
breakForReindexing = true;
break;
}
// Extract sensor state; set up a new observation using either
// the last updated value from sensor state, or if that is missing, right now
SensorState sensorState = sensor.State;
Observation sensorObservation = new Observation();
if (sensorState.Lastupdated.HasValue) {
sensorObservation.observationTime = sensorState.Lastupdated.Value;
}
else {
sensorObservation.observationTime = DateTime.Now;
}
// Defined sensor URI based on local bridge IP and sensor unique id
// TODO: Make sensor URI prefix configurable through Module Twin
sensorObservation.sensorId = new Uri($"http://{clientDescription.ip}/{sensor.UniqueId}");
// Depending on the type of sensor, set the quantity kind and extract values accordingly
// TODO: Figure out quantity kind for boolean, i.e., ZLLPresence
// TODO: Connect this switch statement to the sensorType enum for future maintainability
switch (sensor.Type) {
case "ZLLTemperature":
if (sensorState.Temperature.HasValue) {
sensorObservation.numericValue = ((double)sensorState.Temperature.Value / (double)100);
sensorObservation.quantityKind = new Uri("http://qudt.org/vocab/quantitykind/Temperature");
}
break;
case "ZLLLightLevel":
if (sensorState.LightLevel.HasValue) {
// Parse measurement data (expressed on log scale) into Lux;
// see https://developers.meethue.com/develop/hue-api/supported-devices/#supportred-sensors for details
double luxValue = Math.Pow(10,(((double)sensorState.LightLevel.Value-1.0)/10000.0));
sensorObservation.numericValue = luxValue;
sensorObservation.quantityKind = new Uri("http://qudt.org/vocab/quantitykind/Illuminance");
}
break;
case "ZLLPresence":
if (sensorState.Presence.HasValue) {
sensorObservation.booleanValue = sensorState.Presence.Value;
}
break;
}
recEdgeMessage.observations.Add(sensorObservation);
}
if (breakForReindexing) {
// If we broke out of last loop due to sensor index inconsistency, reindex before proceeding in next SendTelemetry iteration
Twin moduleTwin = await ioTHubModuleClient.GetTwinAsync();
await IndexHueBridges(moduleTwin.Properties.Desired);
breakForReindexing = false;
}
else {
// Otherwise, serialize the REC Edge Message into JSON, built an IoT Edge message, and pass it to the IoT Hub
JsonSerializerSettings serializerSettings = new JsonSerializerSettings {
NullValueHandling = NullValueHandling.Ignore
};
string recEdgeMessageJson = JsonConvert.SerializeObject(recEdgeMessage, Formatting.None, serializerSettings);
Message telemetryMessage = new Message(Encoding.ASCII.GetBytes(recEdgeMessageJson)) {
ContentType = "application/json",
ContentEncoding = "utf-8"
};
Console.WriteLine($"Sending message: {recEdgeMessageJson}");
await ioTHubModuleClient.SendEventAsync(telemetryMessage);
}
await Task.Delay(telemetryInterval, cts.Token);
}
}
static async Task IndexHueBridges(TwinCollection desiredProperties) {
// Only proceed if the module twin contains a hueBridges key
// TODO: exception handling in case of malformed JSON?
if (desiredProperties.Contains("hueBridges")) {
// Reset previous lists of sensors and lights
hueSensors.Clear();
hueLights.Clear();
// Naive lookup through https://discovery.meethue.com
IBridgeLocator locator = new HttpBridgeLocator();
IEnumerable<LocatedBridge> locatedLocalBridges = await locator.LocateBridgesAsync(TimeSpan.FromSeconds(5));
// Iterate over the bridge IDs and corresponding app key credentials provided in the module twin
JArray moduleTwinBridges = desiredProperties["hueBridges"];
foreach (JObject bridge in moduleTwinBridges.Children()) {
string moduleTwinBridgeId = bridge.GetValue("id").ToString();
string moduleTwinAppKey = bridge.GetValue("appKey").ToString();
// If a locally found bridge corresponds with a set of such credentials from the module twin, index it for sensors and lights
IEnumerable<LocatedBridge> locatedBridgesInModuleTwinProperties = locatedLocalBridges.Where(locatedBridge => locatedBridge.BridgeId == moduleTwinBridgeId);
if (locatedBridgesInModuleTwinProperties.Count() == 1) {
LocatedBridge bridgeToIndex = locatedBridgesInModuleTwinProperties.First();
Console.WriteLine($"Will index Hue bridge with ID = {moduleTwinBridgeId} at IP {bridgeToIndex.IpAddress}, using App Key = {moduleTwinAppKey}");
LocalHueClient client = new LocalHueClient(bridgeToIndex.IpAddress, moduleTwinAppKey);
try {
// Index sensors
IReadOnlyCollection<Sensor> sensors = await client.GetSensorsAsync();
foreach(Sensor sensor in sensors) {
if (Enum.IsDefined(typeof(SensorType), sensor.Type)) {
HueDeviceDescription sensorDescription = new HueDeviceDescription() {
id = sensor.Id,
uniqueId = sensor.UniqueId,
};
hueSensors.Add(sensorDescription, new HueClientDescription(){client = client, ip = bridgeToIndex.IpAddress});
Console.WriteLine($"Found sensor: {sensor.Name} ({sensor.UniqueId})");
}
}
// Index lights
IEnumerable<Light> lights = await client.GetLightsAsync();
foreach(Light light in lights) {
hueLights.Add(light.Name);
Console.WriteLine($"Found light: {light.Name} ({light.UniqueId})");
}
}
catch (Exception ex)
{
Console.Error.WriteLine(ex.Message);
Console.Error.WriteLine(ex.StackTrace);
}
}
}
// Report back the results of the indexing; the unique ID:s of each detected Hue device
TwinCollection reportedProperties = new TwinCollection
{
["Sensors"] = hueSensors.Keys.Select(sensorDescription => sensorDescription.uniqueId),
["Lights"] = hueLights
};
await ioTHubModuleClient.UpdateReportedPropertiesAsync(reportedProperties).ConfigureAwait(false);
}
}
