WIP!: maintnofications for cluster

cluster_smigrating_test.go

@@ -0,0 +1,169 @@
+package redis
+
+import (
+	"context"
+	"sync/atomic"
+	"testing"
+
+	"github.com/redis/go-redis/v9/maintnotifications"
+)
+
+// TestClusterClientSMigratedCallback tests that ClusterClient sets up SMIGRATED callback on node clients
+func TestClusterClientSMigratedCallback(t *testing.T) {
+	t.Run("CallbackSetupWithMaintNotifications", func(t *testing.T) {
+		// Track if state reload was called
+		var reloadCalled atomic.Bool
+
+		// Create cluster options with maintnotifications enabled
+		opt := &ClusterOptions{
+			Addrs: []string{"localhost:7000"}, // Dummy address
+			MaintNotificationsConfig: &maintnotifications.Config{
+				Mode: maintnotifications.ModeEnabled,
+			},
+			// Use custom NewClient to track when nodes are created
+			NewClient: func(opt *Options) *Client {
+				client := NewClient(opt)
+				return client
+			},
+		}
+
+		// Create cluster client
+		cluster := NewClusterClient(opt)
+		defer cluster.Close()
+
+		// Manually trigger node creation by calling GetOrCreate
+		// This simulates what happens during normal cluster operations
+		node, err := cluster.nodes.GetOrCreate("localhost:7000")
+		if err != nil {
+			t.Fatalf("Failed to create node: %v", err)
+		}
+
+		// Get the maintnotifications manager from the node client
+		manager := node.Client.GetMaintNotificationsManager()
+		if manager == nil {
+			t.Skip("MaintNotifications manager not initialized (expected if not connected to real Redis)")
+			return
+		}
+
+		// Set up cluster state reload callback for testing
+		var receivedHostPort string
+		var receivedSlotRanges []string
+		manager.SetClusterStateReloadCallback(func(ctx context.Context, hostPort string, slotRanges []string) {
+			reloadCalled.Store(true)
+			receivedHostPort = hostPort
+			receivedSlotRanges = slotRanges
+		})
+
+		// Trigger the callback (this is what SMIGRATED notification would do)
+		ctx := context.Background()
+		testHostPort := "127.0.0.1:6379"
+		testSlotRanges := []string{"1234", "5000-6000"}
+		manager.TriggerClusterStateReload(ctx, testHostPort, testSlotRanges)
+
+		// Verify callback was called
+		if !reloadCalled.Load() {
+			t.Error("Cluster state reload callback should have been called")
+		}
+
+		// Verify host:port was passed correctly
+		if receivedHostPort != testHostPort {
+			t.Errorf("Expected host:port %s, got %s", testHostPort, receivedHostPort)
+		}
+
+		// Verify slot ranges were passed correctly
+		if len(receivedSlotRanges) != len(testSlotRanges) {
+			t.Errorf("Expected %d slot ranges, got %d", len(testSlotRanges), len(receivedSlotRanges))
+		}
+	})
+
+	t.Run("NoCallbackWithoutMaintNotifications", func(t *testing.T) {
+		// Create cluster options WITHOUT maintnotifications
+		opt := &ClusterOptions{
+			Addrs: []string{"localhost:7000"}, // Dummy address
+			// MaintNotificationsConfig is nil
+		}
+
+		// Create cluster client
+		cluster := NewClusterClient(opt)
+		defer cluster.Close()
+
+		// The OnNewNode callback should not be registered when MaintNotificationsConfig is nil
+		// This test just verifies that the cluster client doesn't panic
+	})
+}
+
+// TestClusterClientSMigratedIntegration tests SMIGRATED notification handling in cluster context
+func TestClusterClientSMigratedIntegration(t *testing.T) {
+	t.Run("SMigratedTriggersStateReload", func(t *testing.T) {
+		// This test verifies the integration between SMIGRATED notification and cluster state reload
+		// We verify that the callback is properly set up to call cluster.state.LazyReload()
+
+		// Create cluster options with maintnotifications enabled
+		opt := &ClusterOptions{
+			Addrs: []string{"localhost:7000"},
+			MaintNotificationsConfig: &maintnotifications.Config{
+				Mode: maintnotifications.ModeEnabled,
+			},
+		}
+
+		// Create cluster client
+		cluster := NewClusterClient(opt)
+		defer cluster.Close()
+
+		// Create a node
+		node, err := cluster.nodes.GetOrCreate("localhost:7000")
+		if err != nil {
+			t.Fatalf("Failed to create node: %v", err)
+		}
+
+		// Get the maintnotifications manager
+		manager := node.Client.GetMaintNotificationsManager()
+		if manager == nil {
+			t.Skip("MaintNotifications manager not initialized (expected if not connected to real Redis)")
+			return
+		}
+
+		// Verify that the callback is set by checking it's not nil
+		// We can't directly test LazyReload being called without a real cluster,
+		// but we can verify the callback mechanism works
+		var callbackWorks atomic.Bool
+		var receivedHostPort string
+		var receivedSlotRanges []string
+		manager.SetClusterStateReloadCallback(func(ctx context.Context, hostPort string, slotRanges []string) {
+			callbackWorks.Store(true)
+			receivedHostPort = hostPort
+			receivedSlotRanges = slotRanges
+		})
+
+		ctx := context.Background()
+		testHostPort := "127.0.0.1:7000"
+		testSlotRanges := []string{"5678"}
+		manager.TriggerClusterStateReload(ctx, testHostPort, testSlotRanges)
+
+		if !callbackWorks.Load() {
+			t.Error("Callback mechanism should work")
+		}
+
+		if receivedHostPort != testHostPort {
+			t.Errorf("Expected host:port %s, got %s", testHostPort, receivedHostPort)
+		}
+
+		if len(receivedSlotRanges) != 1 || receivedSlotRanges[0] != "5678" {
+			t.Errorf("Expected slot ranges [5678], got %v", receivedSlotRanges)
+		}
+	})
+}
+
+// TestSMigratingAndSMigratedConstants verifies the SMIGRATING and SMIGRATED constants are exported
+func TestSMigratingAndSMigratedConstants(t *testing.T) {
+	// This test verifies that the SMIGRATING and SMIGRATED constants are properly defined
+	// and accessible from the maintnotifications package
+	if maintnotifications.NotificationSMigrating != "SMIGRATING" {
+		t.Errorf("Expected NotificationSMigrating to be 'SMIGRATING', got: %s", maintnotifications.NotificationSMigrating)
+	}
+
+	if maintnotifications.NotificationSMigrated != "SMIGRATED" {
+		t.Errorf("Expected NotificationSMigrated to be 'SMIGRATED', got: %s", maintnotifications.NotificationSMigrated)
+	}
+}
+

internal/maintnotifications/logs/log_messages.go

@@ -121,6 +121,11 @@ const (
 	UnrelaxedTimeoutMessage                       = "clearing relaxed timeout"
 	ManagerNotInitializedMessage                  = "manager not initialized"
 	FailedToMarkForHandoffMessage                 = "failed to mark connection for handoff"
+	InvalidSeqIDInSMigratingNotificationMessage   = "invalid SeqID in SMIGRATING notification"
+	InvalidSeqIDInSMigratedNotificationMessage    = "invalid SeqID in SMIGRATED notification"
+	InvalidHostPortInSMigratedNotificationMessage = "invalid host:port in SMIGRATED notification"
+	SlotMigratingMessage                          = "slots migrating, applying relaxed timeout"
+	SlotMigratedMessage                           = "slots migrated, triggering cluster state reload"
 
 	// ========================================
 	// used in pool/conn
@@ -623,3 +628,43 @@ func ExtractDataFromLogMessage(logMessage string) map[string]interface{} {
 	// If JSON parsing fails, return empty map
 	return result
 }
+
+// Cluster notification functions
+func InvalidSeqIDInSMigratingNotification(seqID interface{}) string {
+	message := fmt.Sprintf("%s: %v", InvalidSeqIDInSMigratingNotificationMessage, seqID)
+	return appendJSONIfDebug(message, map[string]interface{}{
+		"seqID": fmt.Sprintf("%v", seqID),
+	})
+}
+
+func InvalidSeqIDInSMigratedNotification(seqID interface{}) string {
+	message := fmt.Sprintf("%s: %v", InvalidSeqIDInSMigratedNotificationMessage, seqID)
+	return appendJSONIfDebug(message, map[string]interface{}{
+		"seqID": fmt.Sprintf("%v", seqID),
+	})
+}
+
+func InvalidHostPortInSMigratedNotification(hostPort interface{}) string {
+	message := fmt.Sprintf("%s: %v", InvalidHostPortInSMigratedNotificationMessage, hostPort)
+	return appendJSONIfDebug(message, map[string]interface{}{
+		"hostPort": fmt.Sprintf("%v", hostPort),
+	})
+}
+
+func SlotMigrating(connID uint64, seqID int64, slotRanges []string) string {
+	message := fmt.Sprintf("conn[%d] %s seqID=%d slots=%v", connID, SlotMigratingMessage, seqID, slotRanges)
+	return appendJSONIfDebug(message, map[string]interface{}{
+		"connID":     connID,
+		"seqID":      seqID,
+		"slotRanges": slotRanges,
+	})
+}
+
+func SlotMigrated(seqID int64, hostPort string, slotRanges []string) string {
+	message := fmt.Sprintf("%s seqID=%d host:port=%s slots=%v", SlotMigratedMessage, seqID, hostPort, slotRanges)
+	return appendJSONIfDebug(message, map[string]interface{}{
+		"seqID":      seqID,
+		"hostPort":   hostPort,
+		"slotRanges": slotRanges,
+	})
+}

maintnotifications/README.md

@@ -2,8 +2,14 @@
 
 Seamless Redis connection handoffs during cluster maintenance operations without dropping connections.
 
-## ⚠️ **Important Note**
-**Maintenance notifications are currently supported only in standalone Redis clients.** Cluster clients (ClusterClient, FailoverClient, etc.) do not yet support this functionality.
+## Cluster Support
+
+**Cluster notifications are now supported for ClusterClient!**
+
+- **SMIGRATING**: `["SMIGRATING", SeqID, slot/range, ...]` - Relaxes timeouts when slots are being migrated
+- **SMIGRATED**: `["SMIGRATED", SeqID, host:port, slot/range, ...]` - Reloads cluster state when slot migration completes
+
+**Note:** Other maintenance notifications (MOVING, MIGRATING, MIGRATED, FAILING_OVER, FAILED_OVER) are supported only in standalone Redis clients. Cluster clients support SMIGRATING and SMIGRATED for cluster-specific slot migration handling.
 
 ## Quick Start
 

maintnotifications/manager.go

@@ -18,11 +18,13 @@ import (
 
 // Push notification type constants for maintenance
 const (
-	NotificationMoving      = "MOVING"
-	NotificationMigrating   = "MIGRATING"
-	NotificationMigrated    = "MIGRATED"
-	NotificationFailingOver = "FAILING_OVER"
-	NotificationFailedOver  = "FAILED_OVER"
+	NotificationMoving      = "MOVING"      // Per-connection handoff notification
+	NotificationMigrating   = "MIGRATING"   // Per-connection migration start notification - relaxes timeouts
+	NotificationMigrated    = "MIGRATED"    // Per-connection migration complete notification - clears relaxed timeouts
+	NotificationFailingOver = "FAILING_OVER" // Per-connection failover start notification - relaxes timeouts
+	NotificationFailedOver  = "FAILED_OVER"  // Per-connection failover complete notification - clears relaxed timeouts
+	NotificationSMigrating  = "SMIGRATING"   // Cluster slot migrating notification - relaxes timeouts
+	NotificationSMigrated   = "SMIGRATED"    // Cluster slot migrated notification - triggers cluster state reload
 )
 
 // maintenanceNotificationTypes contains all notification types that maintenance handles
@@ -32,6 +34,8 @@ var maintenanceNotificationTypes = []string{
 	NotificationMigrated,
 	NotificationFailingOver,
 	NotificationFailedOver,
+	NotificationSMigrating,
+	NotificationSMigrated,
 }
 
 // NotificationHook is called before and after notification processing
@@ -73,6 +77,9 @@ type Manager struct {
 	hooks        []NotificationHook
 	hooksMu      sync.RWMutex // Protects hooks slice
 	poolHooksRef *PoolHook
+
+	// Cluster state reload callback for SMIGRATED notifications
+	clusterStateReloadCallback ClusterStateReloadCallback
 }
 
 // MovingOperation tracks an active MOVING operation.
@@ -83,6 +90,14 @@ type MovingOperation struct {
 	Deadline    time.Time
 }
 
+// ClusterStateReloadCallback is a callback function that triggers cluster state reload.
+// This is used by node clients to notify their parent ClusterClient about SMIGRATED notifications.
+// The hostPort parameter indicates the destination node (e.g., "127.0.0.1:6379").
+// The slotRanges parameter contains the migrated slots (e.g., ["1234", "5000-6000"]).
+// Currently, implementations typically reload the entire cluster state, but in the future
+// this could be optimized to reload only the specific slots.
+type ClusterStateReloadCallback func(ctx context.Context, hostPort string, slotRanges []string)
+
 // NewManager creates a new simplified manager.
 func NewManager(client interfaces.ClientInterface, pool pool.Pooler, config *Config) (*Manager, error) {
 	if client == nil {
@@ -318,3 +333,17 @@ func (hm *Manager) AddNotificationHook(notificationHook NotificationHook) {
 	defer hm.hooksMu.Unlock()
 	hm.hooks = append(hm.hooks, notificationHook)
 }
+
+// SetClusterStateReloadCallback sets the callback function that will be called when a SMOVED notification is received.
+// This allows node clients to notify their parent ClusterClient to reload cluster state.
+func (hm *Manager) SetClusterStateReloadCallback(callback ClusterStateReloadCallback) {
+	hm.clusterStateReloadCallback = callback
+}
+
+// TriggerClusterStateReload calls the cluster state reload callback if it's set.
+// This is called when a SMIGRATED notification is received.
+func (hm *Manager) TriggerClusterStateReload(ctx context.Context, hostPort string, slotRanges []string) {
+	if hm.clusterStateReloadCallback != nil {
+		hm.clusterStateReloadCallback(ctx, hostPort, slotRanges)
+	}
+}

maintnotifications/manager_test.go

@@ -217,6 +217,8 @@ func TestManagerRefactoring(t *testing.T) {
 			NotificationMigrated,
 			NotificationFailingOver,
 			NotificationFailedOver,
+			NotificationSMigrating,
+			NotificationSMigrated,
 		}
 
 		if len(maintenanceNotificationTypes) != len(expectedTypes) {