layer1: track namespace removals in manager

doc/thinking/2026-04-26-namespace-manager-step35.md

@@ -0,0 +1,20 @@
+# 2026-04-26 — NamespaceManager rewrite, step 35
+
+## Цель шага
+
+Научить watcher-ы фиксировать label-drop/delete в локальном `NamespaceManager`, не трогая реальные runtime регистрации.
+
+## Что меняем
+
+1. Во все три namespace watcher-а добавляем:
+   - `DeleteFunc`
+   - обработку `managed -> unmanaged` в `UpdateFunc`
+2. При таком событии watcher:
+   - создаёт `NamespaceEventRemove`
+   - записывает его в manager через `Upsert()`
+   - пишет явный log, что runtime cleanup НЕ выполняется
+
+## Что НЕ меняем
+
+- не вызываем `DispatchRemove()` из watcher-ов;
+- не удаляем informer-ы, resolver state или runtime registrations.

pkg/buildermgr/ns_watcher.go

@@ -58,9 +58,20 @@ func StartNSWatcher(
 					zap.String("namespace", nsObj.Name), zap.Error(err))
 			}
 		},
-		UpdateFunc: func(_, newObj interface{}) {
+		UpdateFunc: func(oldObj, newObj interface{}) {
 			nsObj, ok := newObj.(*corev1.Namespace)
-			if !ok || !utils.IsManagedNamespace(nsObj.Labels) {
+			if !ok {
+				return
+			}
+			oldNSObj, _ := oldObj.(*corev1.Namespace)
+			if oldNSObj != nil && utils.IsManagedNamespace(oldNSObj.Labels) && !utils.IsManagedNamespace(nsObj.Labels) {
+				event := utils.NamespaceEventFromNamespace(utils.NamespaceEventRemove, nsObj, utils.NamespaceSourceWatcher, time.Now().UTC())
+				nsManager.Upsert(event)
+				logger.Info("buildermgr.NSWatcher: namespace removed from manager state; runtime registrations kept",
+					zap.String("namespace", nsObj.Name))
+				return
+			}
+			if !utils.IsManagedNamespace(nsObj.Labels) {
 				return
 			}
 			nsManager.Upsert(utils.NamespaceEventFromNamespace(utils.NamespaceEventUpdate, nsObj, utils.NamespaceSourceWatcher, time.Now().UTC()))
@@ -69,6 +80,15 @@ func StartNSWatcher(
 					zap.String("namespace", nsObj.Name), zap.Error(err))
 			}
 		},
+		DeleteFunc: func(obj interface{}) {
+			event := utils.NamespaceEventFromObject(utils.NamespaceEventRemove, obj, utils.NamespaceSourceWatcher, time.Now().UTC())
+			if event.Name == "" {
+				return
+			}
+			nsManager.Upsert(event)
+			logger.Info("buildermgr.NSWatcher: namespace deleted from manager state; runtime registrations kept",
+				zap.String("namespace", event.Name))
+		},
 	})
 
 	mgr.Add(ctx, func(ctx context.Context) {

pkg/executor/multitenant/ns_watcher.go

@@ -127,11 +127,19 @@ func StartNSWatcher(
 		},
 		// UpdateFunc fires when an existing Namespace is updated — covers the case
 		// where the label is added to a pre-existing Namespace.
-		UpdateFunc: func(_, newObj interface{}) {
+		UpdateFunc: func(oldObj, newObj interface{}) {
 			nsObj, ok := newObj.(*corev1.Namespace)
 			if !ok {
 				return
 			}
+			oldNSObj, _ := oldObj.(*corev1.Namespace)
+			if oldNSObj != nil && utils.IsManagedNamespace(oldNSObj.Labels) && !utils.IsManagedNamespace(nsObj.Labels) {
+				event := utils.NamespaceEventFromNamespace(utils.NamespaceEventRemove, nsObj, utils.NamespaceSourceWatcher, time.Now().UTC())
+				nsManager.Upsert(event)
+				logger.Info("multitenant.NSWatcher: namespace removed from manager state; runtime registrations kept",
+					zap.String("namespace", nsObj.Name))
+				return
+			}
 			if !utils.IsManagedNamespace(nsObj.Labels) {
 				return // label was removed — nothing to do (executor keeps existing registrations)
 			}
@@ -141,6 +149,15 @@ func StartNSWatcher(
 					zap.String("namespace", nsObj.Name), zap.Error(err))
 			}
 		},
+		DeleteFunc: func(obj interface{}) {
+			event := utils.NamespaceEventFromObject(utils.NamespaceEventRemove, obj, utils.NamespaceSourceWatcher, time.Now().UTC())
+			if event.Name == "" {
+				return
+			}
+			nsManager.Upsert(event)
+			logger.Info("multitenant.NSWatcher: namespace deleted from manager state; runtime registrations kept",
+				zap.String("namespace", event.Name))
+		},
 	})
 
 	mgr.Add(ctx, func(ctx context.Context) {

pkg/router/ns_watcher.go

@@ -58,9 +58,20 @@ func StartNSWatcher(
 					zap.String("namespace", nsObj.Name), zap.Error(err))
 			}
 		},
-		UpdateFunc: func(_, newObj interface{}) {
+		UpdateFunc: func(oldObj, newObj interface{}) {
 			nsObj, ok := newObj.(*corev1.Namespace)
-			if !ok || !utils.IsManagedNamespace(nsObj.Labels) {
+			if !ok {
+				return
+			}
+			oldNSObj, _ := oldObj.(*corev1.Namespace)
+			if oldNSObj != nil && utils.IsManagedNamespace(oldNSObj.Labels) && !utils.IsManagedNamespace(nsObj.Labels) {
+				event := utils.NamespaceEventFromNamespace(utils.NamespaceEventRemove, nsObj, utils.NamespaceSourceWatcher, time.Now().UTC())
+				nsManager.Upsert(event)
+				logger.Info("router.NSWatcher: namespace removed from manager state; runtime registrations kept",
+					zap.String("namespace", nsObj.Name))
+				return
+			}
+			if !utils.IsManagedNamespace(nsObj.Labels) {
 				return
 			}
 			nsManager.Upsert(utils.NamespaceEventFromNamespace(utils.NamespaceEventUpdate, nsObj, utils.NamespaceSourceWatcher, time.Now().UTC()))
@@ -69,6 +80,15 @@ func StartNSWatcher(
 					zap.String("namespace", nsObj.Name), zap.Error(err))
 			}
 		},
+		DeleteFunc: func(obj interface{}) {
+			event := utils.NamespaceEventFromObject(utils.NamespaceEventRemove, obj, utils.NamespaceSourceWatcher, time.Now().UTC())
+			if event.Name == "" {
+				return
+			}
+			nsManager.Upsert(event)
+			logger.Info("router.NSWatcher: namespace deleted from manager state; runtime registrations kept",
+				zap.String("namespace", event.Name))
+		},
 	})
 
 	mgr.Add(ctx, func(ctx context.Context) {