services/event-subscriber/EventSubscriber.Application/NotificationProjector.cs

@@ -8,12 +8,31 @@ namespace EventSubscriber.Application;
 public sealed class NotificationProjector(INotificationLog log, IProjectionStore store)
 {
     /// <summary>Handle one inbound notification. Ignores anything that is not a zaak-created event.</summary>
-    public Task HandleAsync(Notification notification, CancellationToken ct = default)
-        // RED: not yet implemented — the smallest change to make the tests pass comes next.
-        => Task.CompletedTask;
+    public async Task HandleAsync(Notification notification, CancellationToken ct = default)
+    {
+        if (!notification.IsZaakCreated)
+            return;
+
+        var recorded = new RecordedNotification(notification.IdempotencyKey, notification.Actie, notification.ZaakId);
+
+        // Atomic record-or-skip: a duplicate (or concurrent) delivery is recognised and dropped
+        // before it touches the projection, so the projection stays a faithful derived artefact.
+        if (!await log.TryRecordAsync(recorded, ct))
+            return;
+
+        await store.UpsertAsync(ToEntry(recorded), ct);
+    }
 
     /// <summary>Rebuild the projection from the durable notification log (PRD §8.4).</summary>
-    public Task RebuildAsync(CancellationToken ct = default)
-        // RED: not yet implemented.
-        => Task.CompletedTask;
+    public async Task RebuildAsync(CancellationToken ct = default)
+    {
+        await store.ClearAsync(ct);
+        foreach (var recorded in await log.AllAsync(ct))
+            await store.UpsertAsync(ToEntry(recorded), ct);
+    }
+
+    /// <summary>The minimal projection row for an accepted notification. A zaak-create maps to
+    /// INGEDIEND; bsn/naam are deferred (ADR-0008).</summary>
+    private static RegisterEntry ToEntry(RecordedNotification recorded)
+        => new(recorded.ZaakId, RegistrationStatus.Ingediend);
 }