layer1: add namespace manager subscribers step 9

doc/thinking/2026-04-26-namespace-manager-step9.md

@@ -0,0 +1,20 @@
+# 2026-04-26 — NamespaceManager rewrite, step 9
+
+## Цель шага
+
+Добавить subscriber contract в `NamespaceManager`, не подключая его пока к runtime.
+
+## Что меняем
+
+1. Добавляем interface `NamespaceSubscriber`.
+2. Добавляем в manager операции:
+   - `Subscribe()`
+   - `SnapshotSubscribers()`
+3. Добавляем unit tests на регистрацию и snapshot subscriber-ов.
+
+## Что НЕ меняем
+
+- не вызываем subscriber-ов из watcher-ов;
+- не строим reconcile loop;
+- не трогаем runtime components;
+- не затрагиваем внешнее изменение в `serviceaccount.go`.

pkg/utils/namespace_manager.go

@@ -6,10 +6,16 @@ import (
 	"time"
 )
 
+type NamespaceSubscriber interface {
+	Name() string
+}
+
 type NamespaceManager interface {
 	Snapshot() []string
 	SnapshotRecords() []NamespaceRecord
 	Get(name string) (NamespaceRecord, bool)
+	Subscribe(subscriber NamespaceSubscriber)
+	SnapshotSubscribers() []string
 	Upsert(event NamespaceEvent) NamespaceRecord
 	MarkPartState(namespace string, part string, state NamespacePartState) (NamespaceRecord, bool)
 	Remove(name string) bool
@@ -18,14 +24,34 @@ type NamespaceManager interface {
 type inMemoryNamespaceManager struct {
 	mu      sync.RWMutex
 	records map[string]NamespaceRecord
+	subs    map[string]NamespaceSubscriber
 }
 
 func NewNamespaceManager() NamespaceManager {
 	return &inMemoryNamespaceManager{
 		records: make(map[string]NamespaceRecord),
+		subs:    make(map[string]NamespaceSubscriber),
 	}
 }
 
+func (m *inMemoryNamespaceManager) Subscribe(subscriber NamespaceSubscriber) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	m.subs[subscriber.Name()] = subscriber
+}
+
+func (m *inMemoryNamespaceManager) SnapshotSubscribers() []string {
+	m.mu.RLock()
+	defer m.mu.RUnlock()
+
+	names := make([]string, 0, len(m.subs))
+	for name := range m.subs {
+		names = append(names, name)
+	}
+	sort.Strings(names)
+	return names
+}
+
 func (m *inMemoryNamespaceManager) Snapshot() []string {
 	m.mu.RLock()
 	defer m.mu.RUnlock()

pkg/utils/namespace_manager_test.go

@@ -6,6 +6,14 @@ import (
 	"time"
 )
 
+type testNamespaceSubscriber struct {
+	name string
+}
+
+func (s testNamespaceSubscriber) Name() string {
+	return s.name
+}
+
 func TestNamespaceManagerSnapshotAndGet(t *testing.T) {
 	manager := NewNamespaceManager()
 	now := time.Now().UTC()
@@ -94,3 +102,15 @@ func TestNamespaceManagerSnapshotRecordsReturnsCopies(t *testing.T) {
 		t.Fatalf("expected part states to be detached copies")
 	}
 }
+
+func TestNamespaceManagerSubscribers(t *testing.T) {
+	manager := NewNamespaceManager()
+	manager.Subscribe(testNamespaceSubscriber{name: "router"})
+	manager.Subscribe(testNamespaceSubscriber{name: "buildermgr"})
+	manager.Subscribe(testNamespaceSubscriber{name: "router"})
+
+	expected := []string{"buildermgr", "router"}
+	if !reflect.DeepEqual(expected, manager.SnapshotSubscribers()) {
+		t.Fatalf("expected subscribers %v, got %v", expected, manager.SnapshotSubscribers())
+	}
+}