private static void EnsureDownlinkIsCorrect(DownlinkMessage downlink, SimulatedDevice simDevice, ReceivedLoRaCloudToDeviceMessage sentMessage)
{
Assert.NotNull(downlink);
Assert.False(downlink.Data.IsEmpty);
var downstreamPayloadBytes = downlink.Data;
var downstreamPayload = new LoRaPayloadData(downstreamPayloadBytes);
Assert.Equal(sentMessage.Fport, downstreamPayload.Fport);
Assert.Equal(downstreamPayload.DevAddr, simDevice.DevAddr);
var decryptedPayload = downstreamPayload.GetDecryptedPayload(simDevice.AppSKey.Value);
Assert.Equal(sentMessage.Payload, Encoding.UTF8.GetString(decryptedPayload));
}
private void EnsureDownlinkIsCorrect(DownlinkPktFwdMessage downlink, SimulatedDevice simDevice, ReceivedLoRaCloudToDeviceMessage sentMessage)
{
Assert.NotNull(downlink);
Assert.NotNull(downlink.Txpk);
Assert.True(downlink.Txpk.Imme);
Assert.Equal(0, downlink.Txpk.Tmst);
Assert.NotEmpty(downlink.Txpk.Data);
byte[] downstreamPayloadBytes = Convert.FromBase64String(downlink.Txpk.Data);
var downstreamPayload = new LoRaPayloadData(downstreamPayloadBytes);
Assert.Equal(sentMessage.Fport, downstreamPayload.GetFPort());
Assert.Equal(downstreamPayload.DevAddr.ToArray(), ConversionHelper.StringToByteArray(simDevice.DevAddr));
var decryptedPayload = downstreamPayload.GetDecryptedPayload(simDevice.AppSKey);
Assert.Equal(sentMessage.Payload, Encoding.UTF8.GetString(decryptedPayload));
}
public async Task When_ABP_Sends_Upstream_Followed_By_DirectMethod_Should_Send_Upstream_And_Downstream(string deviceGatewayID, uint fcntDownFromTwin, uint fcntDelta)
{
const uint payloadFcnt = 2; // to avoid relax mode reset
var simDevice = new SimulatedDevice(TestDeviceInfo.CreateABPDevice(1, gatewayID: deviceGatewayID, deviceClassType: 'c'), frmCntDown: fcntDownFromTwin);
this.LoRaDeviceClient.Setup(x => x.UpdateReportedPropertiesAsync(It.IsNotNull <TwinCollection>()))
.ReturnsAsync(true);
var twin = simDevice.CreateABPTwin(reportedProperties: new Dictionary <string, object>
{
{ TwinProperty.Region, LoRaRegionType.EU868.ToString() }
});
this.LoRaDeviceClient.Setup(x => x.GetTwinAsync())
.ReturnsAsync(twin);
this.LoRaDeviceClient.Setup(x => x.SendEventAsync(It.IsNotNull <LoRaDeviceTelemetry>(), null))
.ReturnsAsync(true);
this.LoRaDeviceClient.Setup(x => x.ReceiveAsync(It.IsNotNull <TimeSpan>()))
.ReturnsAsync((Message)null);
this.LoRaDeviceApi.Setup(x => x.SearchByDevAddrAsync(simDevice.DevAddr))
.ReturnsAsync(new SearchDevicesResult(new IoTHubDeviceInfo(simDevice.DevAddr, simDevice.DevEUI, "123").AsList()));
if (deviceGatewayID == null)
{
this.LoRaDeviceApi.Setup(x => x.ExecuteFunctionBundlerAsync(simDevice.DevEUI, It.IsNotNull <FunctionBundlerRequest>()))
.ReturnsAsync(new FunctionBundlerResult());
}
var deviceRegistry = new LoRaDeviceRegistry(this.ServerConfiguration, this.NewMemoryCache(), this.LoRaDeviceApi.Object, this.LoRaDeviceFactory);
var messageDispatcher = new MessageDispatcher(
this.ServerConfiguration,
deviceRegistry,
this.FrameCounterUpdateStrategyProvider);
var request = this.CreateWaitableRequest(simDevice.CreateUnconfirmedMessageUplink("1", fcnt: payloadFcnt).Rxpk[0]);
messageDispatcher.DispatchRequest(request);
Assert.True(await request.WaitCompleteAsync());
Assert.True(request.ProcessingSucceeded);
// wait until cache has been updated
await Task.Delay(50);
// Adds fcntdown to device, simulating multiple downstream calls
Assert.True(deviceRegistry.InternalGetCachedDevicesForDevAddr(simDevice.DevAddr).TryGetValue(simDevice.DevEUI, out var loRaDevice));
loRaDevice.SetFcntDown(fcntDelta + loRaDevice.FCntDown);
var classCSender = new DefaultClassCDevicesMessageSender(
this.ServerConfiguration,
deviceRegistry,
this.PacketForwarder,
this.FrameCounterUpdateStrategyProvider);
var c2d = new ReceivedLoRaCloudToDeviceMessage()
{
DevEUI = simDevice.DevEUI,
MessageId = Guid.NewGuid().ToString(),
Payload = "aaaa",
Fport = 18,
};
var expectedFcntDown = fcntDownFromTwin + Constants.MAX_FCNT_UNSAVED_DELTA + fcntDelta;
if (string.IsNullOrEmpty(deviceGatewayID))
{
this.LoRaDeviceApi.Setup(x => x.NextFCntDownAsync(simDevice.DevEUI, fcntDownFromTwin + fcntDelta, 0, this.ServerConfiguration.GatewayID))
.ReturnsAsync((ushort)expectedFcntDown);
}
Assert.True(await classCSender.SendAsync(c2d));
Assert.Single(this.PacketForwarder.DownlinkMessages);
var downstreamMsg = this.PacketForwarder.DownlinkMessages[0];
byte[] downstreamPayloadBytes = Convert.FromBase64String(downstreamMsg.Txpk.Data);
var downstreamPayload = new LoRaPayloadData(downstreamPayloadBytes);
Assert.Equal(expectedFcntDown, downstreamPayload.GetFcnt());
Assert.Equal(c2d.Fport, downstreamPayload.GetFPort());
Assert.Equal(downstreamPayload.DevAddr.ToArray(), ConversionHelper.StringToByteArray(simDevice.DevAddr));
var decryptedPayload = downstreamPayload.GetDecryptedPayload(simDevice.AppSKey);
Assert.Equal(c2d.Payload, Encoding.UTF8.GetString(decryptedPayload));
Assert.Equal(expectedFcntDown, loRaDevice.FCntDown);
Assert.Equal(payloadFcnt, loRaDevice.FCntUp);
Assert.False(loRaDevice.HasFrameCountChanges);
this.LoRaDeviceApi.VerifyAll();
this.LoRaDeviceClient.VerifyAll();
}
public async Task When_OTAA_Join_Then_Sends_Upstream_DirectMethod_Should_Send_Downstream(string deviceGatewayID)
{
var simDevice = new SimulatedDevice(TestDeviceInfo.CreateOTAADevice(1, deviceClassType: 'c', gatewayID: deviceGatewayID));
this.LoRaDeviceClient.Setup(x => x.GetTwinAsync())
.ReturnsAsync(simDevice.CreateOTAATwin());
var savedAppSKey = string.Empty;
var savedNwkSKey = string.Empty;
var savedDevAddr = string.Empty;
this.LoRaDeviceClient.Setup(x => x.UpdateReportedPropertiesAsync(It.IsNotNull <TwinCollection>()))
.ReturnsAsync(true)
.Callback <TwinCollection>((t) =>
{
savedAppSKey = t[TwinProperty.AppSKey];
savedNwkSKey = t[TwinProperty.NwkSKey];
savedDevAddr = t[TwinProperty.DevAddr];
Assert.NotEmpty(savedAppSKey);
Assert.NotEmpty(savedNwkSKey);
Assert.NotEmpty(savedDevAddr);
});
this.LoRaDeviceClient.Setup(x => x.SendEventAsync(It.IsNotNull <LoRaDeviceTelemetry>(), null))
.ReturnsAsync(true);
this.LoRaDeviceClient.Setup(x => x.ReceiveAsync(It.IsNotNull <TimeSpan>()))
.ReturnsAsync((Message)null);
if (deviceGatewayID == null)
{
this.LoRaDeviceApi.Setup(x => x.ExecuteFunctionBundlerAsync(simDevice.DevEUI, It.IsNotNull <FunctionBundlerRequest>()))
.ReturnsAsync(new FunctionBundlerResult());
}
this.LoRaDeviceApi.Setup(x => x.SearchAndLockForJoinAsync(this.ServerConfiguration.GatewayID, simDevice.DevEUI, simDevice.AppEUI, It.IsNotNull <string>()))
.ReturnsAsync(new SearchDevicesResult(new IoTHubDeviceInfo(simDevice.DevAddr, simDevice.DevEUI, "123").AsList()));
var deviceRegistry = new LoRaDeviceRegistry(this.ServerConfiguration, this.NewMemoryCache(), this.LoRaDeviceApi.Object, this.LoRaDeviceFactory);
var messageDispatcher = new MessageDispatcher(
this.ServerConfiguration,
deviceRegistry,
this.FrameCounterUpdateStrategyProvider);
var joinRxpk = simDevice.CreateJoinRequest().SerializeUplink(simDevice.AppKey).Rxpk[0];
var joinRequest = this.CreateWaitableRequest(joinRxpk);
messageDispatcher.DispatchRequest(joinRequest);
Assert.True(await joinRequest.WaitCompleteAsync());
Assert.True(joinRequest.ProcessingSucceeded);
simDevice.SetupJoin(savedAppSKey, savedNwkSKey, savedDevAddr);
var request = this.CreateWaitableRequest(simDevice.CreateUnconfirmedMessageUplink("1").Rxpk[0]);
messageDispatcher.DispatchRequest(request);
Assert.True(await request.WaitCompleteAsync());
Assert.True(request.ProcessingSucceeded);
var classCSender = new DefaultClassCDevicesMessageSender(
this.ServerConfiguration,
deviceRegistry,
this.PacketForwarder,
this.FrameCounterUpdateStrategyProvider);
var c2d = new ReceivedLoRaCloudToDeviceMessage()
{
DevEUI = simDevice.DevEUI,
MessageId = Guid.NewGuid().ToString(),
Payload = "aaaa",
Fport = 14,
};
if (string.IsNullOrEmpty(deviceGatewayID))
{
this.LoRaDeviceApi.Setup(x => x.NextFCntDownAsync(simDevice.DevEUI, simDevice.FrmCntDown, 0, this.ServerConfiguration.GatewayID))
.ReturnsAsync((ushort)(simDevice.FrmCntDown + 1));
}
Assert.True(await classCSender.SendAsync(c2d));
Assert.Equal(2, this.PacketForwarder.DownlinkMessages.Count);
var downstreamMsg = this.PacketForwarder.DownlinkMessages[1];
TestLogger.Log($"appSKey: {simDevice.AppSKey}, nwkSKey: {simDevice.NwkSKey}");
byte[] downstreamPayloadBytes = Convert.FromBase64String(downstreamMsg.Txpk.Data);
var downstreamPayload = new LoRaPayloadData(downstreamPayloadBytes);
Assert.Equal(1, downstreamPayload.GetFcnt());
Assert.Equal(c2d.Fport, downstreamPayload.GetFPort());
Assert.Equal(downstreamPayload.DevAddr.ToArray(), ConversionHelper.StringToByteArray(savedDevAddr));
var decryptedPayload = downstreamPayload.GetDecryptedPayload(simDevice.AppSKey);
Assert.Equal(c2d.Payload, Encoding.UTF8.GetString(decryptedPayload));
this.LoRaDeviceApi.VerifyAll();
this.LoRaDeviceClient.VerifyAll();
}
public async Task When_ABP_Sends_Upstream_Followed_By_DirectMethod_Should_Send_Upstream_And_Downstream(string deviceGatewayID, uint fcntDownFromTwin, uint fcntDelta, Region region)
{
const uint payloadFcnt = 2; // to avoid relax mode reset
var simDevice = new SimulatedDevice(TestDeviceInfo.CreateABPDevice(1, gatewayID: deviceGatewayID, deviceClassType: 'c'), frmCntDown: fcntDownFromTwin);
LoRaDeviceClient.Setup(x => x.UpdateReportedPropertiesAsync(It.IsNotNull <TwinCollection>(), It.IsAny <CancellationToken>()))
.ReturnsAsync(true);
var twin = simDevice.CreateABPTwin(reportedProperties: new Dictionary <string, object>
{
{ TwinProperty.Region, region.LoRaRegion.ToString() }
});
LoRaDeviceClient.Setup(x => x.GetTwinAsync(CancellationToken.None))
.ReturnsAsync(twin);
LoRaDeviceClient.Setup(x => x.SendEventAsync(It.IsNotNull <LoRaDeviceTelemetry>(), null))
.ReturnsAsync(true);
LoRaDeviceClient.Setup(x => x.ReceiveAsync(It.IsNotNull <TimeSpan>()))
.ReturnsAsync((Message)null);
LoRaDeviceApi.Setup(x => x.SearchByDevAddrAsync(simDevice.DevAddr.Value))
.ReturnsAsync(new SearchDevicesResult(new IoTHubDeviceInfo(simDevice.DevAddr, simDevice.DevEUI, "123").AsList()));
if (deviceGatewayID == null)
{
LoRaDeviceApi.Setup(x => x.ExecuteFunctionBundlerAsync(simDevice.DevEUI, It.IsNotNull <FunctionBundlerRequest>()))
.ReturnsAsync(new FunctionBundlerResult());
}
using var cache = NewMemoryCache();
using var deviceRegistry = new LoRaDeviceRegistry(ServerConfiguration, cache, LoRaDeviceApi.Object, LoRaDeviceFactory, DeviceCache);
using var messageDispatcher = new MessageDispatcher(
ServerConfiguration,
deviceRegistry,
FrameCounterUpdateStrategyProvider);
var payloadData = simDevice.CreateUnconfirmedDataUpMessage("1", fcnt: payloadFcnt);
using var request = CreateWaitableRequest(payloadData, region: region);
request.SetStationEui(new StationEui(ulong.MaxValue));
messageDispatcher.DispatchRequest(request);
Assert.True(await request.WaitCompleteAsync());
Assert.True(request.ProcessingSucceeded);
// wait until cache has been updated
await Task.Delay(50);
// Adds fcntdown to device, simulating multiple downstream calls
Assert.True(DeviceCache.TryGetForPayload(request.Payload, out var loRaDevice));
loRaDevice.SetFcntDown(fcntDelta + loRaDevice.FCntDown);
var classCSender = new DefaultClassCDevicesMessageSender(
ServerConfiguration,
deviceRegistry,
DownstreamMessageSender,
FrameCounterUpdateStrategyProvider,
new TestOutputLogger <DefaultClassCDevicesMessageSender>(this.testOutputHelper),
TestMeter.Instance);
var c2d = new ReceivedLoRaCloudToDeviceMessage()
{
DevEUI = simDevice.DevEUI,
MessageId = Guid.NewGuid().ToString(),
Payload = "aaaa",
Fport = FramePorts.App18,
};
var expectedFcntDown = fcntDownFromTwin + Constants.MaxFcntUnsavedDelta + fcntDelta;
if (string.IsNullOrEmpty(deviceGatewayID))
{
LoRaDeviceApi.Setup(x => x.NextFCntDownAsync(simDevice.DevEUI, fcntDownFromTwin + fcntDelta, 0, ServerConfiguration.GatewayID))
.ReturnsAsync((ushort)expectedFcntDown);
}
Assert.True(await classCSender.SendAsync(c2d));
Assert.Single(DownstreamMessageSender.DownlinkMessages);
var downstreamMsg = DownstreamMessageSender.DownlinkMessages[0];
var downstreamPayloadBytes = downstreamMsg.Data;
var downstreamPayload = new LoRaPayloadData(downstreamPayloadBytes);
Assert.Equal(expectedFcntDown, downstreamPayload.Fcnt);
Assert.Equal(c2d.Fport, downstreamPayload.Fport);
Assert.Equal(downstreamPayload.DevAddr, simDevice.DevAddr);
var decryptedPayload = downstreamPayload.GetDecryptedPayload(simDevice.AppSKey.Value);
Assert.Equal(c2d.Payload, Encoding.UTF8.GetString(decryptedPayload));
Assert.Equal(expectedFcntDown, loRaDevice.FCntDown);
Assert.Equal(payloadFcnt, loRaDevice.FCntUp);
LoRaDeviceApi.VerifyAll();
LoRaDeviceClient.VerifyAll();
}
public async Task When_OTAA_Join_Then_Sends_Upstream_DirectMethod_Should_Send_Downstream(string deviceGatewayID)
{
var simDevice = new SimulatedDevice(TestDeviceInfo.CreateOTAADevice(1, deviceClassType: 'c', gatewayID: deviceGatewayID));
LoRaDeviceClient.Setup(x => x.GetTwinAsync(CancellationToken.None))
.ReturnsAsync(simDevice.CreateOTAATwin());
AppSessionKey? savedAppSKey = null;
NetworkSessionKey?savedNwkSKey = null;
var savedDevAddr = string.Empty;
LoRaDeviceClient.Setup(x => x.UpdateReportedPropertiesAsync(It.IsNotNull <TwinCollection>(), It.IsAny <CancellationToken>()))
.ReturnsAsync(true)
.Callback <TwinCollection, CancellationToken>((t, _) =>
{
savedAppSKey = AppSessionKey.Parse(t[TwinProperty.AppSKey].Value);
savedNwkSKey = NetworkSessionKey.Parse(t[TwinProperty.NwkSKey].Value);
savedDevAddr = t[TwinProperty.DevAddr];
});
LoRaDeviceClient.Setup(x => x.SendEventAsync(It.IsNotNull <LoRaDeviceTelemetry>(), null))
.ReturnsAsync(true);
LoRaDeviceClient.Setup(x => x.ReceiveAsync(It.IsNotNull <TimeSpan>()))
.ReturnsAsync((Message)null);
if (deviceGatewayID == null)
{
LoRaDeviceApi.Setup(x => x.ExecuteFunctionBundlerAsync(simDevice.DevEUI, It.IsNotNull <FunctionBundlerRequest>()))
.ReturnsAsync(new FunctionBundlerResult());
}
LoRaDeviceApi.Setup(x => x.SearchAndLockForJoinAsync(ServerConfiguration.GatewayID, simDevice.DevEUI, It.IsAny <DevNonce>()))
.ReturnsAsync(new SearchDevicesResult(new IoTHubDeviceInfo(simDevice.DevAddr, simDevice.DevEUI, "123").AsList()));
using var cache = NewMemoryCache();
using var deviceRegistry = new LoRaDeviceRegistry(ServerConfiguration, cache, LoRaDeviceApi.Object, LoRaDeviceFactory, DeviceCache);
using var messageDispatcher = new MessageDispatcher(
ServerConfiguration,
deviceRegistry,
FrameCounterUpdateStrategyProvider);
var payloadata = simDevice.CreateJoinRequest();
using var joinRequest = CreateWaitableRequest(payloadata);
joinRequest.SetStationEui(new StationEui(ulong.MaxValue));
messageDispatcher.DispatchRequest(joinRequest);
Assert.True(await joinRequest.WaitCompleteAsync());
Assert.True(joinRequest.ProcessingSucceeded);
Assert.NotNull(savedAppSKey);
Assert.NotNull(savedNwkSKey);
Assert.NotEmpty(savedDevAddr);
simDevice.SetupJoin(savedAppSKey.Value, savedNwkSKey.Value, DevAddr.Parse(savedDevAddr));
using var request = CreateWaitableRequest(simDevice.CreateUnconfirmedDataUpMessage("1"));
request.SetStationEui(new StationEui(ulong.MaxValue));
messageDispatcher.DispatchRequest(request);
Assert.True(await request.WaitCompleteAsync());
Assert.True(request.ProcessingSucceeded);
var classCSender = new DefaultClassCDevicesMessageSender(
ServerConfiguration,
deviceRegistry,
DownstreamMessageSender,
FrameCounterUpdateStrategyProvider,
new TestOutputLogger <DefaultClassCDevicesMessageSender>(this.testOutputHelper),
TestMeter.Instance);
var c2d = new ReceivedLoRaCloudToDeviceMessage()
{
DevEUI = simDevice.DevEUI,
MessageId = Guid.NewGuid().ToString(),
Payload = "aaaa",
Fport = FramePorts.App14,
};
if (string.IsNullOrEmpty(deviceGatewayID))
{
LoRaDeviceApi.Setup(x => x.NextFCntDownAsync(simDevice.DevEUI, simDevice.FrmCntDown, 0, ServerConfiguration.GatewayID))
.ReturnsAsync((ushort)(simDevice.FrmCntDown + 1));
}
Assert.True(await classCSender.SendAsync(c2d));
Assert.Equal(2, DownstreamMessageSender.DownlinkMessages.Count);
var downstreamMsg = DownstreamMessageSender.DownlinkMessages[1];
TestLogger.Log($"appSKey: {simDevice.AppSKey}, nwkSKey: {simDevice.NwkSKey}");
var downstreamPayloadBytes = downstreamMsg.Data;
var downstreamPayload = new LoRaPayloadData(downstreamPayloadBytes);
Assert.Equal(1, downstreamPayload.Fcnt);
Assert.Equal(c2d.Fport, downstreamPayload.Fport);
Assert.Equal(downstreamPayload.DevAddr, DevAddr.Parse(savedDevAddr));
var decryptedPayload = downstreamPayload.GetDecryptedPayload(simDevice.AppSKey.Value);
Assert.Equal(c2d.Payload, Encoding.UTF8.GetString(decryptedPayload));
LoRaDeviceApi.VerifyAll();
LoRaDeviceClient.VerifyAll();
}
/// <summary>
/// Process LoRa message where the payload is of type LoRaPayloadData
/// </summary>
async Task <DownlinkPktFwdMessage> ProcessDataMessageAsync(LoRaTools.LoRaPhysical.Rxpk rxpk, LoRaPayloadData loraPayload, DateTime startTime)
{
var devAddr = loraPayload.DevAddr;
var timeWatcher = new LoRaOperationTimeWatcher(this.loraRegion, startTime);
using (var processLogger = new ProcessLogger(timeWatcher, devAddr))
{
if (!this.IsValidNetId(loraPayload.GetDevAddrNetID(), this.configuration.NetId))
{
Logger.Log(ConversionHelper.ByteArrayToString(devAddr), "device is using another network id, ignoring this message", LogLevel.Debug);
processLogger.LogLevel = LogLevel.Debug;
return(null);
}
// Find device that matches:
// - devAddr
// - mic check (requires: loraDeviceInfo.NwkSKey or loraDeviceInfo.AppKey, rxpk.LoraPayload.Mic)
// - gateway id
var loRaDevice = await this.deviceRegistry.GetDeviceForPayloadAsync(loraPayload);
if (loRaDevice == null)
{
Logger.Log(ConversionHelper.ByteArrayToString(devAddr), $"device is not from our network, ignoring message", LogLevel.Information);
return(null);
}
// Add context to logger
processLogger.SetDevEUI(loRaDevice.DevEUI);
var isMultiGateway = !string.Equals(loRaDevice.GatewayID, this.configuration.GatewayID, StringComparison.InvariantCultureIgnoreCase);
var frameCounterStrategy = isMultiGateway ? this.frameCounterUpdateStrategyFactory.GetMultiGatewayStrategy() : this.frameCounterUpdateStrategyFactory.GetSingleGatewayStrategy();
var payloadFcnt = loraPayload.GetFcnt();
var requiresConfirmation = loraPayload.IsConfirmed();
using (new LoRaDeviceFrameCounterSession(loRaDevice, frameCounterStrategy))
{
// Leaf devices that restart lose the counter. In relax mode we accept the incoming frame counter
// ABP device does not reset the Fcnt so in relax mode we should reset for 0 (LMIC based) or 1
var isFrameCounterFromNewlyStartedDevice = false;
if (payloadFcnt <= 1)
{
if (loRaDevice.IsABP)
{
if (loRaDevice.IsABPRelaxedFrameCounter && loRaDevice.FCntUp >= 0 && payloadFcnt <= 1)
{
// known problem when device restarts, starts fcnt from zero
_ = frameCounterStrategy.ResetAsync(loRaDevice);
isFrameCounterFromNewlyStartedDevice = true;
}
}
else if (loRaDevice.FCntUp == payloadFcnt && payloadFcnt == 0)
{
// Some devices start with frame count 0
isFrameCounterFromNewlyStartedDevice = true;
}
}
// Reply attack or confirmed reply
// Confirmed resubmit: A confirmed message that was received previously but we did not answer in time
// Device will send it again and we just need to return an ack (but also check for C2D to send it over)
var isConfirmedResubmit = false;
if (!isFrameCounterFromNewlyStartedDevice && payloadFcnt <= loRaDevice.FCntUp)
{
// if it is confirmed most probably we did not ack in time before or device lost the ack packet so we should continue but not send the msg to iothub
if (requiresConfirmation && payloadFcnt == loRaDevice.FCntUp)
{
if (!loRaDevice.ValidateConfirmResubmit(payloadFcnt))
{
Logger.Log(loRaDevice.DevEUI, $"resubmit from confirmed message exceeds threshold of {LoRaDevice.MaxConfirmationResubmitCount}, message ignored, msg: {payloadFcnt} server: {loRaDevice.FCntUp}", LogLevel.Debug);
processLogger.LogLevel = LogLevel.Debug;
return(null);
}
isConfirmedResubmit = true;
Logger.Log(loRaDevice.DevEUI, $"resubmit from confirmed message detected, msg: {payloadFcnt} server: {loRaDevice.FCntUp}", LogLevel.Information);
}
else
{
Logger.Log(loRaDevice.DevEUI, $"invalid frame counter, message ignored, msg: {payloadFcnt} server: {loRaDevice.FCntUp}", LogLevel.Information);
return(null);
}
}
var fcntDown = 0;
// If it is confirmed it require us to update the frame counter down
// Multiple gateways: in redis, otherwise in device twin
if (requiresConfirmation)
{
fcntDown = await frameCounterStrategy.NextFcntDown(loRaDevice, payloadFcnt);
// Failed to update the fcnt down
// In multi gateway scenarios it means the another gateway was faster than using, can stop now
if (fcntDown <= 0)
{
// update our fcntup anyway?
// loRaDevice.SetFcntUp(payloadFcnt);
Logger.Log(loRaDevice.DevEUI, "another gateway has already sent ack or downlink msg", LogLevel.Information);
return(null);
}
Logger.Log(loRaDevice.DevEUI, $"down frame counter: {loRaDevice.FCntDown}", LogLevel.Information);
}
if (!isConfirmedResubmit)
{
var validFcntUp = isFrameCounterFromNewlyStartedDevice || (payloadFcnt > loRaDevice.FCntUp);
if (validFcntUp)
{
Logger.Log(loRaDevice.DevEUI, $"valid frame counter, msg: {payloadFcnt} server: {loRaDevice.FCntUp}", LogLevel.Information);
object payloadData = null;
// if it is an upward acknowledgement from the device it does not have a payload
// This is confirmation from leaf device that he received a C2D confirmed
// if a message payload is null we don't try to decrypt it.
if (loraPayload.Frmpayload.Length != 0)
{
byte[] decryptedPayloadData = null;
try
{
decryptedPayloadData = loraPayload.GetDecryptedPayload(loRaDevice.AppSKey);
}
catch (Exception ex)
{
Logger.Log(loRaDevice.DevEUI, $"failed to decrypt message: {ex.Message}", LogLevel.Error);
}
var fportUp = loraPayload.GetFPort();
if (string.IsNullOrEmpty(loRaDevice.SensorDecoder))
{
Logger.Log(loRaDevice.DevEUI, $"no decoder set in device twin. port: {fportUp}", LogLevel.Debug);
payloadData = Convert.ToBase64String(decryptedPayloadData);
}
else
{
Logger.Log(loRaDevice.DevEUI, $"decoding with: {loRaDevice.SensorDecoder} port: {fportUp}", LogLevel.Debug);
payloadData = await this.payloadDecoder.DecodeMessageAsync(decryptedPayloadData, fportUp, loRaDevice.SensorDecoder);
}
}
if (!await this.SendDeviceEventAsync(loRaDevice, rxpk, payloadData, loraPayload, timeWatcher))
{
// failed to send event to IoT Hub, stop now
return(null);
}
loRaDevice.SetFcntUp(payloadFcnt);
}
else
{
Logger.Log(loRaDevice.DevEUI, $"invalid frame counter, msg: {payloadFcnt} server: {loRaDevice.FCntUp}", LogLevel.Information);
}
}
// We check if we have time to futher progress or not
// C2D checks are quite expensive so if we are really late we just stop here
var timeToSecondWindow = timeWatcher.GetRemainingTimeToReceiveSecondWindow(loRaDevice);
if (timeToSecondWindow < LoRaOperationTimeWatcher.ExpectedTimeToPackageAndSendMessage)
{
if (requiresConfirmation)
{
Logger.Log(loRaDevice.DevEUI, $"too late for down message ({timeWatcher.GetElapsedTime()}), sending only ACK to gateway", LogLevel.Information);
}
return(null);
}
// If it is confirmed and
// - Downlink is disabled for the device or
// - we don't have time to check c2d and send to device we return now
if (requiresConfirmation && (!loRaDevice.DownlinkEnabled || timeToSecondWindow.Subtract(LoRaOperationTimeWatcher.ExpectedTimeToPackageAndSendMessage) <= LoRaOperationTimeWatcher.MinimumAvailableTimeToCheckForCloudMessage))
{
return(this.CreateDownlinkMessage(
null,
loRaDevice,
rxpk,
loraPayload,
timeWatcher,
devAddr,
false, // fpending
(ushort)fcntDown));
}
// Flag indicating if there is another C2D message waiting
var fpending = false;
// Contains the Cloud to message we need to send
Message cloudToDeviceMessage = null;
if (loRaDevice.DownlinkEnabled)
{
// ReceiveAsync has a longer timeout
// But we wait less that the timeout (available time before 2nd window)
// if message is received after timeout, keep it in loraDeviceInfo and return the next call
var timeAvailableToCheckCloudToDeviceMessages = timeWatcher.GetAvailableTimeToCheckCloudToDeviceMessage(loRaDevice);
if (timeAvailableToCheckCloudToDeviceMessages >= LoRaOperationTimeWatcher.MinimumAvailableTimeToCheckForCloudMessage)
{
cloudToDeviceMessage = await loRaDevice.ReceiveCloudToDeviceAsync(timeAvailableToCheckCloudToDeviceMessages);
if (cloudToDeviceMessage != null && !this.ValidateCloudToDeviceMessage(loRaDevice, cloudToDeviceMessage))
{
_ = loRaDevice.CompleteCloudToDeviceMessageAsync(cloudToDeviceMessage);
cloudToDeviceMessage = null;
}
if (cloudToDeviceMessage != null)
{
if (!requiresConfirmation)
{
// The message coming from the device was not confirmed, therefore we did not computed the frame count down
// Now we need to increment because there is a C2D message to be sent
fcntDown = await frameCounterStrategy.NextFcntDown(loRaDevice, payloadFcnt);
if (fcntDown == 0)
{
// We did not get a valid frame count down, therefore we should not process the message
_ = loRaDevice.AbandonCloudToDeviceMessageAsync(cloudToDeviceMessage);
cloudToDeviceMessage = null;
}
else
{
requiresConfirmation = true;
}
Logger.Log(loRaDevice.DevEUI, $"down frame counter: {loRaDevice.FCntDown}", LogLevel.Information);
}
// Checking again if cloudToDeviceMessage is valid because the fcntDown resolution could have failed,
// causing us to drop the message
if (cloudToDeviceMessage != null)
{
var remainingTimeForFPendingCheck = timeWatcher.GetRemainingTimeToReceiveSecondWindow(loRaDevice) - (LoRaOperationTimeWatcher.CheckForCloudMessageCallEstimatedOverhead + LoRaOperationTimeWatcher.MinimumAvailableTimeToCheckForCloudMessage);
if (remainingTimeForFPendingCheck >= LoRaOperationTimeWatcher.MinimumAvailableTimeToCheckForCloudMessage)
{
var additionalMsg = await loRaDevice.ReceiveCloudToDeviceAsync(LoRaOperationTimeWatcher.MinimumAvailableTimeToCheckForCloudMessage);
if (additionalMsg != null)
{
fpending = true;
_ = loRaDevice.AbandonCloudToDeviceMessageAsync(additionalMsg);
Logger.Log(loRaDevice.DevEUI, $"found fpending c2d message id: {additionalMsg.MessageId ?? "undefined"}", LogLevel.Information);
}
}
}
}
}
}
// No C2D message and request was not confirmed, return nothing
if (!requiresConfirmation)
{
return(null);
}
var confirmDownstream = this.CreateDownlinkMessage(
cloudToDeviceMessage,
loRaDevice,
rxpk,
loraPayload,
timeWatcher,
devAddr,
fpending,
(ushort)fcntDown);
if (cloudToDeviceMessage != null)
{
if (confirmDownstream == null)
{
Logger.Log(loRaDevice.DevEUI, $"out of time for downstream message, will abandon c2d message id: {cloudToDeviceMessage.MessageId ?? "undefined"}", LogLevel.Information);
_ = loRaDevice.AbandonCloudToDeviceMessageAsync(cloudToDeviceMessage);
}
else
{
_ = loRaDevice.CompleteCloudToDeviceMessageAsync(cloudToDeviceMessage);
}
}
return(confirmDownstream);
}
}
}