WIP

PlanTempus.Tests/Logging/SeqTelemetryChannelTest.cs

@@ -0,0 +1,60 @@
+using Autofac;
+using Microsoft.ApplicationInsights;
+using Microsoft.ApplicationInsights.Channel;
+using Microsoft.ApplicationInsights.DataContracts;
+using PlanTempus.Core.SeqLogging;
+using PlanTempus.Core.Telemetry;
+
+namespace PlanTempus.X.TDD.Logging;
+
+[TestClass]
+public class SeqTelemetryChannelTest : TestFixture
+{
+    private CancellationTokenSource _cts;
+    private IMessageChannel<ITelemetry> _messageChannel;
+    private SeqBackgroundService _service;
+    private TelemetryClient _telemetryClient;
+
+    [TestInitialize]
+    public void SetupThis()
+    {
+        //it is important to use the same MessageChannel as the BackgroundService uses
+        //we know that IMessageChannel<ITelemetry> _messageChannel; is registered via Autofac and manually injected into SeqBackgroundService
+        //so we can get it by calling the Autofac Container in this test.
+
+        _messageChannel = Container.Resolve<IMessageChannel<ITelemetry>>();
+        _service = Container.Resolve<SeqBackgroundService>();
+        _telemetryClient = Container.Resolve<TelemetryClient>();
+
+        _cts = new CancellationTokenSource();
+    }
+
+    [TestMethod]
+    public async Task Messages_ShouldBeProcessedFromQueue()
+    {
+        await _service.StartAsync(_cts.Token);
+
+        for (var i = 0; i < 5; i++)
+        {
+            var eventTelemetry = new EventTelemetry
+            {
+                Name = "Test Event 3",
+                Timestamp = DateTimeOffset.UtcNow
+            };
+
+            eventTelemetry.Properties.Add("TestId", Guid.NewGuid().ToString());
+            eventTelemetry.Metrics.Add("TestMetric", 42.0);
+
+            //we don't write to the  _messageChannel.Writer.WriteAsync(eventTelemetry);, but the TelemetryClient which is configured to use SeqTelemetryChannel
+            _telemetryClient.TrackEvent(eventTelemetry);
+        }
+
+        // wait for processing
+        await Task.Delay(5000);
+
+        await _service.StopAsync(CancellationToken.None);
+
+        var hasMoreMessages = await _messageChannel.Reader.WaitToReadAsync();
+        Assert.IsFalse(hasMoreMessages, "Queue should be empty after 5 seconds");
+    }
+}