More work on SeqBackgroundService, next step is tests for it.

Core/Logging/SeqBackgroundService.cs

@@ -0,0 +1,81 @@
+using Core.Telemetry;
+using Microsoft.ApplicationInsights;
+using Microsoft.ApplicationInsights.Channel;
+using Microsoft.ApplicationInsights.DataContracts;
+using Microsoft.Extensions.Hosting;
+
+namespace Core.Logging
+{
+    public class SeqBackgroundService : BackgroundService
+    {
+        private readonly IMessageChannel<ITelemetry> _messageChannel;
+        private readonly TelemetryClient _telemetryClient;
+        private readonly SeqLogger _seqLogger;
+
+        public SeqBackgroundService(TelemetryClient telemetryClient,
+                                    IMessageChannel<ITelemetry> messageChannel,
+                                    SeqLogger seqlogger)
+        {
+            _telemetryClient = telemetryClient;
+            _messageChannel = messageChannel;
+            _seqLogger = seqlogger;
+
+        }
+
+        protected override async Task ExecuteAsync(CancellationToken stoppingToken)
+        {
+            try
+            {
+                while (!stoppingToken.IsCancellationRequested)
+                    await foreach (var telemetry in _messageChannel.Reader.ReadAllAsync(stoppingToken))
+                    {
+                        try
+                        {
+                            switch (telemetry)
+                            {
+                                case ExceptionTelemetry et:
+                                    await _seqLogger.LogAsync(et);
+                                    break;
+
+                                case TraceTelemetry et:
+                                    await _seqLogger.LogAsync(et);
+                                    break;
+
+                                case DependencyTelemetry et:
+                                    await _seqLogger.LogAsync(et);
+                                    break;
+
+                                case RequestTelemetry et:
+                                    await _seqLogger.LogAsync(et);
+                                    break;
+
+                                default:
+                                    throw new NotSupportedException(telemetry.GetType().Name);
+                            }
+                        }
+                        catch
+                        {
+                            throw;
+                            //_telemetryClient.TrackException(ex); this is disabled for now, we need to think about the channel structure first
+                        }
+                    }
+            }
+            catch (Exception ex)
+            {
+                if (ex is not OperationCanceledException)
+                {
+                    _telemetryClient.TrackException(ex);
+                    throw;
+                }
+
+                _telemetryClient.TrackTrace("Service shutdown started");
+            }
+        }
+
+        public override async Task StopAsync(CancellationToken cancellationToken)
+        {
+            _messageChannel.Dispose();
+            await base.StopAsync(cancellationToken);
+        }
+    }
+}