Publish curated Knowledge Hub source from 2ed833f290b439a7bc91e5fd19b042c269e3bee9

src/backend/ItWorx.KnowledgeHub.Api/BackgroundServices/OperationalTelemetryBackgroundService.cs

@@ -0,0 +1,41 @@
+using ItWorx.KnowledgeHub.Application.Operations;
+
+namespace ItWorx.KnowledgeHub.Api.BackgroundServices;
+
+public sealed partial class OperationalTelemetryBackgroundService(
+    IServiceScopeFactory scopeFactory, PlatformMetrics metrics, TimeProvider clock,
+    ILogger<OperationalTelemetryBackgroundService> logger) : BackgroundService
+{
+    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
+    {
+        while (!stoppingToken.IsCancellationRequested)
+        {
+            try
+            {
+                // Do not race initial database migration during host startup.
+                await Task.Delay(TimeSpan.FromSeconds(30), clock, stoppingToken);
+                using var scope = scopeFactory.CreateScope();
+                var snapshot = await scope.ServiceProvider.GetRequiredService<IOperationalTelemetryReader>()
+                    .ReadAsync(stoppingToken);
+                var now = clock.GetUtcNow();
+                metrics.SetQueueState(snapshot.QueuedJobs, snapshot.RunningJobs, snapshot.FailedJobs,
+                    Age(snapshot.OldestQueuedJobAt, now));
+                metrics.SetOperationalAges(Age(snapshot.OldestPendingIngestionAt, now),
+                    Age(snapshot.LatestInventoryCaptureAt, now), Age(snapshot.LatestVerifiedBackupAt, now));
+            }
+            catch (OperationCanceledException) when (stoppingToken.IsCancellationRequested) { break; }
+            catch (Exception)
+            {
+                // Omit stale gauges after a failed read, rather than exporting old success.
+                metrics.ClearSnapshots();
+                LogReadFailed();
+            }
+        }
+    }
+
+    private static double? Age(DateTimeOffset? value, DateTimeOffset now) =>
+        value is { } time && time <= now ? (now - time).TotalSeconds : null;
+
+    [LoggerMessage(Level = LogLevel.Warning, Message = "Operationele metriekmeting mislukt; waarden blijven onbekend tot de volgende geslaagde meting.")]
+    private partial void LogReadFailed();
+}