From 5d16e93bda625bf5096807cc7e880683a2b6127c Mon Sep 17 00:00:00 2001
From: Denis-Cosmin Nutiu <dnutiu@bitdefender.com>
Date: Mon, 20 Apr 2020 13:30:22 +0300
Subject: [PATCH] NUC-37: Add exception handling to the workers.

---
 NucuCar.Sensors/NucuCar.Sensors.csproj |  4 --
 NucuCar.Sensors/SensorWorker.cs        | 66 +++++++++++++++-----------
 NucuCar.Telemetry/TelemetryWorker.cs   | 37 +++++++++------
 3 files changed, 61 insertions(+), 46 deletions(-)

diff --git a/NucuCar.Sensors/NucuCar.Sensors.csproj b/NucuCar.Sensors/NucuCar.Sensors.csproj
index c257cd8..b9c5b5c 100644
--- a/NucuCar.Sensors/NucuCar.Sensors.csproj
+++ b/NucuCar.Sensors/NucuCar.Sensors.csproj
@@ -81,8 +81,4 @@
       <ProjectReference Include="..\NucuCar.Domain\NucuCar.Domain.csproj" />
       <ProjectReference Include="..\NucuCar.Telemetry\NucuCar.Telemetry.csproj" />
     </ItemGroup>
-
-    <ItemGroup>
-      <Folder Include="Telemetry" />
-    </ItemGroup>
 </Project>
diff --git a/NucuCar.Sensors/SensorWorker.cs b/NucuCar.Sensors/SensorWorker.cs
index 2bca3c4..c89f0e9 100644
--- a/NucuCar.Sensors/SensorWorker.cs
+++ b/NucuCar.Sensors/SensorWorker.cs
@@ -1,3 +1,4 @@
+using System;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.Extensions.Hosting;
@@ -27,41 +28,50 @@ namespace NucuCar.Sensors
             {
                 return;
             }
+
             var sensorIdentifier = Sensor.GetIdentifier();
             Logger?.LogInformation($"Starting sensor worker for {sensorIdentifier}");
-            TelemetryPublisher?.RegisterTelemeter(Sensor);
-
-            Sensor.Initialize();
-            while (!stoppingToken.IsCancellationRequested)
+            try
             {
-                var sensorState = Sensor.GetState();
-                /* If sensor is ok attempt to read. */
-                if (sensorState == SensorStateEnum.Initialized)
+                TelemetryPublisher?.RegisterTelemeter(Sensor);
+
+                Sensor.Initialize();
+                while (!stoppingToken.IsCancellationRequested)
                 {
-                    Logger?.LogTrace($"{sensorIdentifier} is taking a measurement!");
-                    await Sensor.TakeMeasurementAsync();
-                }
-                /* Else attempt to re-initialize. */
-                else if (sensorState == SensorStateEnum.Uninitialized ||
-                         sensorState == SensorStateEnum.Error)
-                {
-                    Logger?.LogWarning(
-                        $"{sensorIdentifier} is in {sensorState}! Attempting to re-initialize in {_intializationDelay}ms.");
-                    _intializationDelay += 10000;
-                    await Task.Delay(_intializationDelay, stoppingToken);
-                    Sensor.Initialize();
-                }
-                else if (sensorState == SensorStateEnum.Disabled)
-                {
-                    // Break from while.
-                    Logger?.LogInformation($"{sensorIdentifier} has been disabled!");
-                    break;
+                    var sensorState = Sensor.GetState();
+                    /* If sensor is ok attempt to read. */
+                    if (sensorState == SensorStateEnum.Initialized)
+                    {
+                        Logger?.LogTrace($"{sensorIdentifier} is taking a measurement!");
+                        await Sensor.TakeMeasurementAsync();
+                    }
+                    /* Else attempt to re-initialize. */
+                    else if (sensorState == SensorStateEnum.Uninitialized ||
+                             sensorState == SensorStateEnum.Error)
+                    {
+                        Logger?.LogWarning(
+                            $"{sensorIdentifier} is in {sensorState}! Attempting to re-initialize in {_intializationDelay}ms.");
+                        _intializationDelay += 10000;
+                        await Task.Delay(_intializationDelay, stoppingToken);
+                        Sensor.Initialize();
+                    }
+                    else if (sensorState == SensorStateEnum.Disabled)
+                    {
+                        // Break from while.
+                        Logger?.LogInformation($"{sensorIdentifier} has been disabled!");
+                        break;
+                    }
+
+                    await Task.Delay(MeasurementInterval, stoppingToken);
                 }
 
-                await Task.Delay(MeasurementInterval, stoppingToken);
+                TelemetryPublisher?.UnRegisterTelemeter(Sensor);
+            }
+            catch (Exception e)
+            {
+                Logger?.LogError($"Unhandled exception in SensorWorker {sensorIdentifier}: {e.Message}");
+                Logger?.LogDebug(e.StackTrace);
             }
-
-            TelemetryPublisher?.UnRegisterTelemeter(Sensor);
         }
     }
 }
\ No newline at end of file
diff --git a/NucuCar.Telemetry/TelemetryWorker.cs b/NucuCar.Telemetry/TelemetryWorker.cs
index 642d7c9..9676b59 100644
--- a/NucuCar.Telemetry/TelemetryWorker.cs
+++ b/NucuCar.Telemetry/TelemetryWorker.cs
@@ -1,3 +1,4 @@
+using System;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.Extensions.Hosting;
@@ -28,24 +29,32 @@ namespace NucuCar.Telemetry
 
         protected override async Task ExecuteAsync(CancellationToken stoppingToken)
         {
-            if (!_serviceEnabled)
+            try
             {
-                _logger.LogInformation("Telemetry service is disabled!");
-                return;
-            }
+                if (!_serviceEnabled)
+                {
+                    _logger.LogInformation("Telemetry service is disabled!");
+                    return;
+                }
 
-            if (_telemetryPublisher == null)
-            {
-                _logger?.LogCritical("Invalid state! TelemetryPublisher is null!");
-                return;
-            }
+                if (_telemetryPublisher == null)
+                {
+                    _logger?.LogCritical("Invalid state! TelemetryPublisher is null!");
+                    return;
+                }
 
-            await Task.Delay(_interval, stoppingToken);
-            while (!stoppingToken.IsCancellationRequested)
-            {
-                await _telemetryPublisher.PublishAsync(stoppingToken);
-                _logger?.LogDebug("Telemetry data published!");
                 await Task.Delay(_interval, stoppingToken);
+                while (!stoppingToken.IsCancellationRequested)
+                {
+                    await _telemetryPublisher.PublishAsync(stoppingToken);
+                    _logger?.LogDebug("Telemetry data published!");
+                    await Task.Delay(_interval, stoppingToken);
+                }
+            }
+            catch (Exception e)
+            {
+                _logger?.LogError($"Unhandled exception in TelemetryWorker. {e.Message}");
+                _logger?.LogDebug(e.StackTrace);
             }
         }
     }