update example and tests, drop connectionAdapter

.github/copilot-instructions.md

@@ -311,9 +311,50 @@ func (opt *Options) init() {
 
 ```go
 type NotificationProcessor interface {
-    ProcessPushNotification(ctx context.Context, data []byte) error
+    RegisterHandler(pushNotificationName string, handler interface{}, protected bool) error
-    RegisterHandler(notificationType string, handler NotificationHandler) error
+    UnregisterHandler(pushNotificationName string) error
-    Close() error
+    GetHandler(pushNotificationName string) interface{}
+}
+
+type NotificationHandler interface {
+    HandlePushNotification(ctx context.Context, handlerCtx NotificationHandlerContext, notification []interface{}) error
+}
+```
+
+### Notification Hooks
+
+```go
+type NotificationHook interface {
+    PreHook(ctx context.Context, notificationCtx push.NotificationHandlerContext, notificationType string, notification []interface{}) ([]interface{}, bool)
+    PostHook(ctx context.Context, notificationCtx push.NotificationHandlerContext, notificationType string, notification []interface{}, result error)
+}
+
+// NotificationHandlerContext provides context for notification processing
+type NotificationHandlerContext struct {
+    Client     interface{} // Redis client instance
+    Pool       interface{} // Connection pool
+    Conn       interface{} // Specific connection (*pool.Conn)
+    IsBlocking bool        // Whether notification was on blocking connection
+}
+```
+
+### Hook Implementation Pattern
+
+```go
+func (h *CustomHook) PreHook(ctx context.Context, notificationCtx push.NotificationHandlerContext, notificationType string, notification []interface{}) ([]interface{}, bool) {
+    // Access connection information
+    if conn, ok := notificationCtx.Conn.(*pool.Conn); ok {
+        connID := conn.GetID()
+        // Process with connection context
+    }
+    return notification, true // Continue processing
+}
+
+func (h *CustomHook) PostHook(ctx context.Context, notificationCtx push.NotificationHandlerContext, notificationType string, notification []interface{}, result error) {
+    // Handle processing result
+    if result != nil {
+        // Log or handle error
+    }
 }
 ```
 

adapters.go

@@ -7,7 +7,6 @@ import (
 	"time"
 
 	"github.com/redis/go-redis/v9/internal/interfaces"
-	"github.com/redis/go-redis/v9/internal/pool"
 	"github.com/redis/go-redis/v9/push"
 )
 
@@ -88,43 +87,6 @@ func (oa *optionsAdapter) NewDialer() func(context.Context) (net.Conn, error) {
 	}
 }
 
-// connectionAdapter adapts a Redis connection to interfaces.ConnectionWithRelaxedTimeout
-type connectionAdapter struct {
-	conn *pool.Conn
-}
-
-// Close closes the connection.
-func (ca *connectionAdapter) Close() error {
-	return ca.conn.Close()
-}
-
-// IsUsable returns true if the connection is safe to use for new commands.
-func (ca *connectionAdapter) IsUsable() bool {
-	return ca.conn.IsUsable()
-}
-
-// GetPoolConn returns the underlying pool connection.
-func (ca *connectionAdapter) GetPoolConn() *pool.Conn {
-	return ca.conn
-}
-
-// SetRelaxedTimeout sets relaxed timeouts for this connection during hitless upgrades.
-// These timeouts remain active until explicitly cleared.
-func (ca *connectionAdapter) SetRelaxedTimeout(readTimeout, writeTimeout time.Duration) {
-	ca.conn.SetRelaxedTimeout(readTimeout, writeTimeout)
-}
-
-// SetRelaxedTimeoutWithDeadline sets relaxed timeouts with an expiration deadline.
-// After the deadline, timeouts automatically revert to normal values.
-func (ca *connectionAdapter) SetRelaxedTimeoutWithDeadline(readTimeout, writeTimeout time.Duration, deadline time.Time) {
-	ca.conn.SetRelaxedTimeoutWithDeadline(readTimeout, writeTimeout, deadline)
-}
-
-// ClearRelaxedTimeout clears relaxed timeouts for this connection.
-func (ca *connectionAdapter) ClearRelaxedTimeout() {
-	ca.conn.ClearRelaxedTimeout()
-}
-
 // pushProcessorAdapter adapts a push.NotificationProcessor to implement interfaces.NotificationProcessor.
 type pushProcessorAdapter struct {
 	processor push.NotificationProcessor

example/pubsub/main.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"log"
 	"sync"
+	"sync/atomic"
 	"time"
 
 	"github.com/redis/go-redis/v9"
@@ -12,11 +13,15 @@ import (
 )
 
 var ctx = context.Background()
+var cntErrors atomic.Int64
+var cntSuccess atomic.Int64
+var startTime = time.Now()
 
 // This example is not supposed to be run as is. It is just a test to see how pubsub behaves in relation to pool management.
 // It was used to find regressions in pool management in hitless mode.
 // Please don't use it as a reference for how to use pubsub.
 func main() {
+	startTime = time.Now()
 	wg := &sync.WaitGroup{}
 	rdb := redis.NewClient(&redis.Options{
 		Addr: ":6379",
@@ -25,6 +30,12 @@ func main() {
 		},
 	})
 	_ = rdb.FlushDB(ctx).Err()
+	hitlessManager := rdb.GetHitlessManager()
+	if hitlessManager == nil {
+		panic("hitless manager is nil")
+	}
+	loggingHook := hitless.NewLoggingHook(3)
+	hitlessManager.AddNotificationHook(loggingHook)
 
 	go func() {
 		for {
@@ -62,7 +73,8 @@ func main() {
 	subCtx, cancelSubCtx = context.WithCancel(ctx)
 	for i := 0; i < 10; i++ {
 		if err := rdb.Incr(ctx, "publishers").Err(); err != nil {
-			panic(err)
+			fmt.Println("incr error:", err)
+			cntErrors.Add(1)
 		}
 		wg.Add(1)
 		go floodThePool(pubCtx, rdb, wg)
@@ -70,12 +82,14 @@ func main() {
 
 	for i := 0; i < 500; i++ {
 		if err := rdb.Incr(ctx, "subscribers").Err(); err != nil {
-			panic(err)
+			fmt.Println("incr error:", err)
+			cntErrors.Add(1)
 		}
+
 		wg.Add(1)
 		go subscribe(subCtx, rdb, "test2", i, wg)
 	}
-	time.Sleep(5 * time.Second)
+	time.Sleep(120 * time.Second)
 	fmt.Println("canceling publishers")
 	cancelPublishers()
 	time.Sleep(10 * time.Second)
@@ -95,6 +109,9 @@ func main() {
 	fmt.Printf("if drained = published*subscribers: %d\n", publishedInt*subscribersInt)
 
 	time.Sleep(2 * time.Second)
+	fmt.Println("errors:", cntErrors.Load())
+	fmt.Println("success:", cntSuccess.Load())
+	fmt.Println("time:", time.Since(startTime))
 }
 
 func floodThePool(ctx context.Context, rdb *redis.Client, wg *sync.WaitGroup) {
@@ -107,14 +124,18 @@ func floodThePool(ctx context.Context, rdb *redis.Client, wg *sync.WaitGroup) {
 		}
 		err := rdb.Publish(ctx, "test2", "hello").Err()
 		if err != nil {
-			// noop
+			if err.Error() != "context canceled" {
-			//log.Println("publish error:", err)
+				log.Println("publish error:", err)
+				cntErrors.Add(1)
+			}
 		}
 
 		err = rdb.Incr(ctx, "published").Err()
 		if err != nil {
-			// noop
+			if err.Error() != "context canceled" {
-			//log.Println("incr error:", err)
+				log.Println("incr error:", err)
+				cntErrors.Add(1)
+			}
 		}
 		time.Sleep(10 * time.Nanosecond)
 	}
@@ -137,7 +158,10 @@ func subscribe(ctx context.Context, rdb *redis.Client, topic string, subscriberI
 			case msg := <-recChan:
 				err := rdb.Incr(ctx, "received").Err()
 				if err != nil {
-					log.Println("incr error:", err)
+					if err.Error() != "context canceled" {
+						log.Printf("%s\n", err.Error())
+						cntErrors.Add(1)
+					}
 				}
 				_ = msg // Use the message to avoid unused variable warning
 			}

hitless/README.md

@@ -49,23 +49,62 @@ Config: &hitless.Config{
 - **Auto-calculated**: `10 × MaxWorkers`, capped by pool size
 - **Always capped**: Queue size never exceeds pool size
 
-## Metrics Hook Example
+## Notification Hooks
 
-A metrics collection hook is available in `example_hooks.go` that demonstrates how to monitor hitless upgrade operations:
+Notification hooks allow you to monitor and customize hitless upgrade operations. The `NotificationHook` interface provides pre and post processing hooks:
+
+```go
+type NotificationHook interface {
+    PreHook(ctx context.Context, notificationCtx push.NotificationHandlerContext, notificationType string, notification []interface{}) ([]interface{}, bool)
+    PostHook(ctx context.Context, notificationCtx push.NotificationHandlerContext, notificationType string, notification []interface{}, result error)
+}
+```
+
+### Example: Metrics Collection Hook
+
+A metrics collection hook is available in `example_hooks.go`:
 
 ```go
 import "github.com/redis/go-redis/v9/hitless"
 
 metricsHook := hitless.NewMetricsHook()
-// Use with your monitoring system
+manager.AddNotificationHook(metricsHook)
+
+// Access metrics
+metrics := metricsHook.GetMetrics()
 ```
 
-The metrics hook tracks:
+### Example: Custom Logging Hook
+
+```go
+type CustomHook struct{}
+
+func (h *CustomHook) PreHook(ctx context.Context, notificationCtx push.NotificationHandlerContext, notificationType string, notification []interface{}) ([]interface{}, bool) {
+    // Log notification with connection details
+    if conn, ok := notificationCtx.Conn.(*pool.Conn); ok {
+        log.Printf("Processing %s on connection %d", notificationType, conn.GetID())
+    }
+    return notification, true // Continue processing
+}
+
+func (h *CustomHook) PostHook(ctx context.Context, notificationCtx push.NotificationHandlerContext, notificationType string, notification []interface{}, result error) {
+    if result != nil {
+        log.Printf("Failed to process %s: %v", notificationType, result)
+    }
+}
+```
+
+The notification context provides access to:
+- **Client**: The Redis client instance
+- **Pool**: The connection pool
+- **Conn**: The specific connection that received the notification
+- **IsBlocking**: Whether the notification was received on a blocking connection
+
+Hooks can track:
 - Handoff success/failure rates
-- Handoff duration
+- Processing duration
-- Queue depth
+- Connection-specific metrics
-- Worker utilization
+- Custom business logic
-- Connection lifecycle events
 
 ## Requirements
 

hitless/example_hooks.go

@@ -3,6 +3,10 @@ package hitless
 import (
 	"context"
 	"time"
+
+	"github.com/redis/go-redis/v9/internal"
+	"github.com/redis/go-redis/v9/internal/pool"
+	"github.com/redis/go-redis/v9/push"
 )
 
 // contextKey is a custom type for context keys to avoid collisions
@@ -29,9 +33,14 @@ func NewMetricsHook() *MetricsHook {
 }
 
 // PreHook records the start time for processing metrics.
-func (mh *MetricsHook) PreHook(ctx context.Context, notificationType string, notification []interface{}) ([]interface{}, bool) {
+func (mh *MetricsHook) PreHook(ctx context.Context, notificationCtx push.NotificationHandlerContext, notificationType string, notification []interface{}) ([]interface{}, bool) {
 	mh.NotificationCounts[notificationType]++
 
+	// Log connection information if available
+	if conn, ok := notificationCtx.Conn.(*pool.Conn); ok {
+		internal.Logger.Printf(ctx, "hitless: metrics hook processing %s notification on connection %d", notificationType, conn.GetID())
+	}
+
 	// Store start time in context for duration calculation
 	startTime := time.Now()
 	_ = context.WithValue(ctx, startTimeKey, startTime) // Context not used further
@@ -40,7 +49,7 @@ func (mh *MetricsHook) PreHook(ctx context.Context, notificationType string, not
 }
 
 // PostHook records processing completion and any errors.
-func (mh *MetricsHook) PostHook(ctx context.Context, notificationType string, notification []interface{}, result error) {
+func (mh *MetricsHook) PostHook(ctx context.Context, notificationCtx push.NotificationHandlerContext, notificationType string, notification []interface{}, result error) {
 	// Calculate processing duration
 	if startTime, ok := ctx.Value(startTimeKey).(time.Time); ok {
 		duration := time.Since(startTime)
@@ -50,6 +59,11 @@ func (mh *MetricsHook) PostHook(ctx context.Context, notificationType string, no
 	// Record errors
 	if result != nil {
 		mh.ErrorCounts[notificationType]++
+
+		// Log error details with connection information
+		if conn, ok := notificationCtx.Conn.(*pool.Conn); ok {
+			internal.Logger.Printf(ctx, "hitless: metrics hook recorded error for %s notification on connection %d: %v", notificationType, conn.GetID(), result)
+		}
 	}
 }
 

hitless/hitless_manager.go

@@ -11,6 +11,7 @@ import (
 	"github.com/redis/go-redis/v9/internal"
 	"github.com/redis/go-redis/v9/internal/interfaces"
 	"github.com/redis/go-redis/v9/internal/pool"
+	"github.com/redis/go-redis/v9/push"
 )
 
 // Push notification type constants for hitless upgrades
@@ -35,8 +36,8 @@ var hitlessNotificationTypes = []string{
 // PreHook can modify the notification and return false to skip processing
 // PostHook is called after successful processing
 type NotificationHook interface {
-	PreHook(ctx context.Context, notificationType string, notification []interface{}) ([]interface{}, bool)
+	PreHook(ctx context.Context, notificationCtx push.NotificationHandlerContext, notificationType string, notification []interface{}) ([]interface{}, bool)
-	PostHook(ctx context.Context, notificationType string, notification []interface{}, result error)
+	PostHook(ctx context.Context, notificationCtx push.NotificationHandlerContext, notificationType string, notification []interface{}, result error)
 }
 
 // MovingOperationKey provides a unique key for tracking MOVING operations
@@ -252,14 +253,14 @@ func (hm *HitlessManager) GetState() State {
 }
 
 // processPreHooks calls all pre-hooks and returns the modified notification and whether to continue processing.
-func (hm *HitlessManager) processPreHooks(ctx context.Context, notificationType string, notification []interface{}) ([]interface{}, bool) {
+func (hm *HitlessManager) processPreHooks(ctx context.Context, notificationCtx push.NotificationHandlerContext, notificationType string, notification []interface{}) ([]interface{}, bool) {
 	hm.hooksMu.RLock()
 	defer hm.hooksMu.RUnlock()
 
 	currentNotification := notification
 
 	for _, hook := range hm.hooks {
-		modifiedNotification, shouldContinue := hook.PreHook(ctx, notificationType, currentNotification)
+		modifiedNotification, shouldContinue := hook.PreHook(ctx, notificationCtx, notificationType, currentNotification)
 		if !shouldContinue {
 			return modifiedNotification, false
 		}
@@ -270,12 +271,12 @@ func (hm *HitlessManager) processPreHooks(ctx context.Context, notificationType
 }
 
 // processPostHooks calls all post-hooks with the processing result.
-func (hm *HitlessManager) processPostHooks(ctx context.Context, notificationType string, notification []interface{}, result error) {
+func (hm *HitlessManager) processPostHooks(ctx context.Context, notificationCtx push.NotificationHandlerContext, notificationType string, notification []interface{}, result error) {
 	hm.hooksMu.RLock()
 	defer hm.hooksMu.RUnlock()
 
 	for _, hook := range hm.hooks {
-		hook.PostHook(ctx, notificationType, notification, result)
+		hook.PostHook(ctx, notificationCtx, notificationType, notification, result)
 	}
 }
 

hitless/hooks.go

@@ -4,6 +4,8 @@ import (
 	"context"
 
 	"github.com/redis/go-redis/v9/internal"
+	"github.com/redis/go-redis/v9/internal/pool"
+	"github.com/redis/go-redis/v9/push"
 )
 
 // LoggingHook is an example hook implementation that logs all notifications.
@@ -12,19 +14,28 @@ type LoggingHook struct {
 }
 
 // PreHook logs the notification before processing and allows modification.
-func (lh *LoggingHook) PreHook(ctx context.Context, notificationType string, notification []interface{}) ([]interface{}, bool) {
+func (lh *LoggingHook) PreHook(ctx context.Context, notificationCtx push.NotificationHandlerContext, notificationType string, notification []interface{}) ([]interface{}, bool) {
 	if lh.LogLevel >= 2 { // Info level
-		internal.Logger.Printf(ctx, "hitless: processing %s notification: %v", notificationType, notification)
+		// Log the notification type and content
+		connID := uint64(0)
+		if conn, ok := notificationCtx.Conn.(*pool.Conn); ok {
+			connID = conn.GetID()
+		}
+		internal.Logger.Printf(ctx, "hitless: conn[%d] processing %s notification: %v", connID, notificationType, notification)
 	}
 	return notification, true // Continue processing with unmodified notification
 }
 
 // PostHook logs the result after processing.
-func (lh *LoggingHook) PostHook(ctx context.Context, notificationType string, notification []interface{}, result error) {
+func (lh *LoggingHook) PostHook(ctx context.Context, notificationCtx push.NotificationHandlerContext, notificationType string, notification []interface{}, result error) {
+	connID := uint64(0)
+	if conn, ok := notificationCtx.Conn.(*pool.Conn); ok {
+		connID = conn.GetID()
+	}
 	if result != nil && lh.LogLevel >= 1 { // Warning level
-		internal.Logger.Printf(ctx, "hitless: %s notification processing failed: %v - %v", notificationType, result, notification)
+		internal.Logger.Printf(ctx, "hitless: conn[%d] %s notification processing failed: %v - %v", connID, notificationType, result, notification)
 	} else if lh.LogLevel >= 3 { // Debug level
-		internal.Logger.Printf(ctx, "hitless: %s notification processed successfully", notificationType)
+		internal.Logger.Printf(ctx, "hitless: conn[%d] %s notification processed successfully", connID, notificationType)
 	}
 }
 

hitless/notification_handler.go

@@ -30,7 +30,7 @@ func (snh *NotificationHandler) HandlePushNotification(ctx context.Context, hand
 	}
 
 	// Process pre-hooks - they can modify the notification or skip processing
-	modifiedNotification, shouldContinue := snh.manager.processPreHooks(ctx, notificationType, notification)
+	modifiedNotification, shouldContinue := snh.manager.processPreHooks(ctx, handlerCtx, notificationType, notification)
 	if !shouldContinue {
 		return nil // Hooks decided to skip processing
 	}
@@ -53,7 +53,7 @@ func (snh *NotificationHandler) HandlePushNotification(ctx context.Context, hand
 	}
 
 	// Process post-hooks with the result
-	snh.manager.processPostHooks(ctx, notificationType, modifiedNotification, err)
+	snh.manager.processPostHooks(ctx, handlerCtx, notificationType, modifiedNotification, err)
 
 	return err
 }
@@ -97,9 +97,7 @@ func (snh *NotificationHandler) handleMoving(ctx context.Context, handlerCtx pus
 
 	// Type assert to get the underlying pool connection
 	var poolConn *pool.Conn
-	if connAdapter, ok := conn.(interface{ GetPoolConn() *pool.Conn }); ok {
+	if pc, ok := conn.(*pool.Conn); ok {
-		poolConn = connAdapter.GetPoolConn()
-	} else if pc, ok := conn.(*pool.Conn); ok {
 		poolConn = pc
 	} else {
 		internal.Logger.Printf(ctx, "hitless: invalid connection type in handler context for MOVING notification - %T %#v", conn, handlerCtx)
@@ -157,13 +155,11 @@ func (snh *NotificationHandler) handleMigrating(ctx context.Context, handlerCtx
 		return ErrInvalidNotification
 	}
 
-	// Get the connection from handler context and type assert to connectionAdapter
 	if handlerCtx.Conn == nil {
 		internal.Logger.Printf(ctx, "hitless: no connection in handler context for MIGRATING notification")
 		return ErrInvalidNotification
 	}
 
-	// Type assert to connectionAdapter which implements ConnectionWithRelaxedTimeout
 	connAdapter, ok := handlerCtx.Conn.(interfaces.ConnectionWithRelaxedTimeout)
 	if !ok {
 		internal.Logger.Printf(ctx, "hitless: invalid connection type in handler context for MIGRATING notification")
@@ -184,13 +180,11 @@ func (snh *NotificationHandler) handleMigrated(ctx context.Context, handlerCtx p
 		return ErrInvalidNotification
 	}
 
-	// Get the connection from handler context and type assert to connectionAdapter
 	if handlerCtx.Conn == nil {
 		internal.Logger.Printf(ctx, "hitless: no connection in handler context for MIGRATED notification")
 		return ErrInvalidNotification
 	}
 
-	// Type assert to connectionAdapter which implements ConnectionWithRelaxedTimeout
 	connAdapter, ok := handlerCtx.Conn.(interfaces.ConnectionWithRelaxedTimeout)
 	if !ok {
 		internal.Logger.Printf(ctx, "hitless: invalid connection type in handler context for MIGRATED notification")
@@ -211,13 +205,11 @@ func (snh *NotificationHandler) handleFailingOver(ctx context.Context, handlerCt
 		return ErrInvalidNotification
 	}
 
-	// Get the connection from handler context and type assert to connectionAdapter
 	if handlerCtx.Conn == nil {
 		internal.Logger.Printf(ctx, "hitless: no connection in handler context for FAILING_OVER notification")
 		return ErrInvalidNotification
 	}
 
-	// Type assert to connectionAdapter which implements ConnectionWithRelaxedTimeout
 	connAdapter, ok := handlerCtx.Conn.(interfaces.ConnectionWithRelaxedTimeout)
 	if !ok {
 		internal.Logger.Printf(ctx, "hitless: invalid connection type in handler context for FAILING_OVER notification")
@@ -238,13 +230,11 @@ func (snh *NotificationHandler) handleFailedOver(ctx context.Context, handlerCtx
 		return ErrInvalidNotification
 	}
 
-	// Get the connection from handler context and type assert to connectionAdapter
 	if handlerCtx.Conn == nil {
 		internal.Logger.Printf(ctx, "hitless: no connection in handler context for FAILED_OVER notification")
 		return ErrInvalidNotification
 	}
 
-	// Type assert to connectionAdapter which implements ConnectionWithRelaxedTimeout
 	connAdapter, ok := handlerCtx.Conn.(interfaces.ConnectionWithRelaxedTimeout)
 	if !ok {
 		internal.Logger.Printf(ctx, "hitless: invalid connection type in handler context for FAILED_OVER notification")

hitless/pool_hook.go

@@ -117,7 +117,7 @@ func (ph *PoolHook) IsHandoffPending(conn *pool.Conn) bool {
 }
 
 // OnGet is called when a connection is retrieved from the pool
-func (ph *PoolHook) OnGet(ctx context.Context, conn *pool.Conn, isNewConn bool) error {
+func (ph *PoolHook) OnGet(ctx context.Context, conn *pool.Conn, _ bool) error {
 	// NOTE: There are two conditions to make sure we don't return a connection that should be handed off or is
 	// in a handoff state at the moment.
 
@@ -234,6 +234,7 @@ func (ph *PoolHook) onDemandWorker() {
 func (ph *PoolHook) processHandoffRequest(request HandoffRequest) {
 	// Remove from pending map
 	defer ph.pending.Delete(request.Conn.GetID())
+	internal.Logger.Printf(context.Background(), "hitless: conn[%d] Processing handoff request start", request.Conn.GetID())
 
 	// Create a context with handoff timeout from config
 	handoffTimeout := 30 * time.Second // Default fallback
@@ -366,6 +367,7 @@ func (ph *PoolHook) performConnectionHandoffWithPool(ctx context.Context, conn *
 	}
 
 	retries := conn.IncrementAndGetHandoffRetries(1)
+	internal.Logger.Printf(ctx, "hitless: conn[%d] Retry %d: Performing handoff to %s(was %s)", conn.GetID(), retries, newEndpoint, conn.RemoteAddr().String())
 	maxRetries := 3 // Default fallback
 	if ph.config != nil {
 		maxRetries = ph.config.MaxHandoffRetries
@@ -387,6 +389,7 @@ func (ph *PoolHook) performConnectionHandoffWithPool(ctx context.Context, conn *
 	// Create new connection to the new endpoint
 	newNetConn, err := endpointDialer(ctx)
 	if err != nil {
+		internal.Logger.Printf(ctx, "hitless: conn[%d] Failed to dial new endpoint %s: %v", conn.GetID(), newEndpoint, err)
 		// hitless: will retry
 		// Maybe a network error - retry after a delay
 		return true, err
@@ -409,6 +412,7 @@ func (ph *PoolHook) performConnectionHandoffWithPool(ctx context.Context, conn *
 	}()
 
 	conn.ClearHandoffState()
+	internal.Logger.Printf(ctx, "hitless: conn[%d] Handoff to %s successful", conn.GetID(), newEndpoint)
 
 	// Apply relaxed timeout to the new connection for the configured post-handoff duration
 	// This gives the new connection more time to handle operations during cluster transition

internal/pool/pubsub.go

@@ -5,6 +5,8 @@ import (
 	"net"
 	"sync"
 	"sync/atomic"
+
+	"github.com/redis/go-redis/v9/internal"
 )
 
 type PubSubStats struct {
@@ -52,6 +54,9 @@ func (p *PubSubPool) TrackConn(cn *Conn) {
 }
 
 func (p *PubSubPool) UntrackConn(cn *Conn) {
+	if !cn.IsUsable() || cn.ShouldHandoff() {
+		internal.Logger.Printf(context.Background(), "pubsub: untracking connection %d [usable, handoff] = [%v, %v]", cn.GetID(), cn.IsUsable(), cn.ShouldHandoff())
+	}
 	atomic.AddUint32(&p.stats.Active, ^uint32(0))
 	atomic.AddUint32(&p.stats.Untracked, 1)
 	p.activeConns.Delete(cn.GetID())

pubsub.go

@@ -170,10 +170,16 @@ func (c *PubSub) releaseConn(ctx context.Context, cn *pool.Conn, err error, allo
 	}
 
 	if !cn.IsUsable() || cn.ShouldHandoff() {
+		if cn.ShouldHandoff() {
+			internal.Logger.Printf(ctx, "pubsub: connection[%d] is marked for handoff, reconnecting", cn.GetID())
+		} else {
+			internal.Logger.Printf(ctx, "pubsub: connection[%d] is not usable, reconnecting", cn.GetID())
+		}
 		c.reconnect(ctx, fmt.Errorf("pubsub: connection is not usable"))
 	}
 
 	if isBadConn(err, allowTimeout, c.opt.Addr) {
+		internal.Logger.Printf(ctx, "pubsub: releasing connection[%d]: %v", cn.GetID(), err)
 		c.reconnect(ctx, err)
 	}
 }
@@ -187,7 +193,10 @@ func (c *PubSub) reconnect(ctx context.Context, reason error) {
 		}
 
 		if newEndpoint != "" {
+			// Update the address in the options
+			oldAddr := c.cn.RemoteAddr().String()
 			c.opt.Addr = newEndpoint
+			internal.Logger.Printf(ctx, "pubsub: reconnecting to new endpoint %s (was %s)", newEndpoint, oldAddr)
 		}
 	}
 	_ = c.closeTheCn(reason)
@@ -199,7 +208,7 @@ func (c *PubSub) closeTheCn(reason error) error {
 		return nil
 	}
 	if !c.closed {
-		internal.Logger.Printf(c.getContext(), "redis: discarding bad PubSub connection: %s", reason)
+		internal.Logger.Printf(c.getContext(), "redis: discarding bad PubSub connection[%d]: %s, %v", c.cn.GetID(), reason, c.cn.RemoteAddr())
 	}
 	err := c.closeConn(c.cn)
 	c.cn = nil

push/handler_context.go

@@ -37,7 +37,6 @@ type NotificationHandlerContext struct {
 	// circular dependencies. The developer is responsible for type assertion.
 	// It can be one of the following types:
 	// - *pool.Conn
-	// - *connectionAdapter (for hitless upgrades)
 	Conn interface{}
 
 	// IsBlocking indicates if the notification was received on a blocking connection.

redis.go

@@ -1077,6 +1077,7 @@ func (c *Client) pubSub() *PubSub {
 			// will return nil if already initialized
 			err = c.initConn(ctx, cn)
 			if err != nil {
+				internal.Logger.Printf(ctx, "pubsub: conn[%d] to ADDR %s [usable, handoff] = [%v, %v] after initConn returned %v", cn.GetID(), addr, cn.IsUsable(), cn.ShouldHandoff(), err)
 				_ = cn.Close()
 				return nil, err
 			}
@@ -1277,7 +1278,7 @@ func (c *baseClient) pushNotificationHandlerContext(cn *pool.Conn) push.Notifica
 	return push.NotificationHandlerContext{
 		Client:   c,
 		ConnPool: c.connPool,
-		Conn:     &connectionAdapter{conn: cn}, // Wrap in adapter for easier interface access
+		Conn:     cn, // Wrap in adapter for easier interface access
 	}
 }