Fix basepool & 优化 repo

internal/repository/key_selector.go

@@ -1,4 +1,4 @@
-// Filename: internal/repository/key_selector.go (经审查后最终修复版)
+// Filename: internal/repository/key_selector.go
 package repository
 
 import (
@@ -18,39 +18,40 @@ import (
 )
 
 const (
-	CacheTTL             = 5 * time.Minute
-	EmptyPoolPlaceholder = "EMPTY_POOL"
-	EmptyCacheTTL        = 1 * time.Minute
+	CacheTTL      = 5 * time.Minute
+	EmptyCacheTTL = 1 * time.Minute
 )
 
-// SelectOneActiveKey 根据指定的轮询策略，从缓存中高效地选取一个可用的API密钥。
+// SelectOneActiveKey 根据指定的轮询策略，从单个密钥组缓存中选取一个可用的API密钥。
 func (r *gormKeyRepository) SelectOneActiveKey(ctx context.Context, group *models.KeyGroup) (*models.APIKey, *models.GroupAPIKeyMapping, error) {
+	if group == nil {
+		return nil, nil, fmt.Errorf("group cannot be nil")
+	}
 	var keyIDStr string
 	var err error
-
 	switch group.PollingStrategy {
 	case models.StrategySequential:
 		sequentialKey := fmt.Sprintf(KeyGroupSequential, group.ID)
 		keyIDStr, err = r.store.Rotate(ctx, sequentialKey)
-
 	case models.StrategyWeighted:
 		lruKey := fmt.Sprintf(KeyGroupLRU, group.ID)
 		results, zerr := r.store.ZRange(ctx, lruKey, 0, 0)
-		if zerr == nil && len(results) > 0 {
-			keyIDStr = results[0]
+		if zerr == nil {
+			if len(results) > 0 {
+				keyIDStr = results[0]
+			} else {
+				zerr = gorm.ErrRecordNotFound
+			}
 		}
 		err = zerr
-
 	case models.StrategyRandom:
 		mainPoolKey := fmt.Sprintf(KeyGroupRandomMain, group.ID)
 		cooldownPoolKey := fmt.Sprintf(KeyGroupRandomCooldown, group.ID)
 		keyIDStr, err = r.store.PopAndCycleSetMember(ctx, mainPoolKey, cooldownPoolKey)
-
-	default: // 默认或未指定策略时，使用基础的随机策略
+	default:
 		activeKeySetKey := fmt.Sprintf(KeyGroup, group.ID)
 		keyIDStr, err = r.store.SRandMember(ctx, activeKeySetKey)
 	}
-
 	if err != nil {
 		if errors.Is(err, store.ErrNotFound) || errors.Is(err, gorm.ErrRecordNotFound) {
 			return nil, nil, gorm.ErrRecordNotFound
@@ -58,39 +59,44 @@ func (r *gormKeyRepository) SelectOneActiveKey(ctx context.Context, group *model
 		r.logger.WithError(err).Errorf("Failed to select key for group %d with strategy %s", group.ID, group.PollingStrategy)
 		return nil, nil, err
 	}
-
 	if keyIDStr == "" {
 		return nil, nil, gorm.ErrRecordNotFound
 	}
-
-	keyID, _ := strconv.ParseUint(keyIDStr, 10, 64)
-
+	keyID, parseErr := strconv.ParseUint(keyIDStr, 10, 64)
+	if parseErr != nil {
+		r.logger.WithError(parseErr).Errorf("Invalid key ID format in group %d cache: %s", group.ID, keyIDStr)
+		return nil, nil, fmt.Errorf("invalid key ID in cache: %w", parseErr)
+	}
 	apiKey, mapping, err := r.getKeyDetailsFromCache(ctx, uint(keyID), group.ID)
 	if err != nil {
-		r.logger.WithError(err).Warnf("Cache inconsistency: Failed to get details for selected key ID %d", keyID)
+		r.logger.WithError(err).Warnf("Cache inconsistency for key ID %d in group %d", keyID, group.ID)
 		return nil, nil, err
 	}
-
 	if group.PollingStrategy == models.StrategyWeighted {
-		go r.UpdateKeyUsageTimestamp(context.Background(), group.ID, uint(keyID))
+		go func() {
+			updateCtx, cancel := r.withTimeout(5 * time.Second)
+			defer cancel()
+			r.UpdateKeyUsageTimestamp(updateCtx, group.ID, uint(keyID))
+		}()
 	}
-
 	return apiKey, mapping, nil
 }
 
-// SelectOneActiveKeyFromBasePool 为智能聚合模式设计的全新轮询器。
+// SelectOneActiveKeyFromBasePool 从智能聚合池中选取一个可用Key。
 func (r *gormKeyRepository) SelectOneActiveKeyFromBasePool(ctx context.Context, pool *BasePool) (*models.APIKey, *models.KeyGroup, error) {
-	poolID := generatePoolID(pool.CandidateGroups)
+	if pool == nil || len(pool.CandidateGroups) == 0 {
+		return nil, nil, fmt.Errorf("invalid or empty base pool configuration")
+	}
+	poolID := r.generatePoolID(pool.CandidateGroups)
 	log := r.logger.WithField("pool_id", poolID)
-
 	if err := r.ensureBasePoolCacheExists(ctx, pool, poolID); err != nil {
-		log.WithError(err).Error("Failed to ensure BasePool cache exists.")
+		if !errors.Is(err, gorm.ErrRecordNotFound) {
+			log.WithError(err).Error("Failed to ensure BasePool cache exists")
+		}
 		return nil, nil, err
 	}
-
 	var keyIDStr string
 	var err error
-
 	switch pool.PollingStrategy {
 	case models.StrategySequential:
 		sequentialKey := fmt.Sprintf(BasePoolSequential, poolID)
@@ -98,8 +104,12 @@ func (r *gormKeyRepository) SelectOneActiveKeyFromBasePool(ctx context.Context,
 	case models.StrategyWeighted:
 		lruKey := fmt.Sprintf(BasePoolLRU, poolID)
 		results, zerr := r.store.ZRange(ctx, lruKey, 0, 0)
-		if zerr == nil && len(results) > 0 {
-			keyIDStr = results[0]
+		if zerr == nil {
+			if len(results) > 0 {
+				keyIDStr = results[0]
+			} else {
+				zerr = gorm.ErrRecordNotFound
+			}
 		}
 		err = zerr
 	case models.StrategyRandom:
@@ -107,13 +117,12 @@ func (r *gormKeyRepository) SelectOneActiveKeyFromBasePool(ctx context.Context,
 		cooldownPoolKey := fmt.Sprintf(BasePoolRandomCooldown, poolID)
 		keyIDStr, err = r.store.PopAndCycleSetMember(ctx, mainPoolKey, cooldownPoolKey)
 	default:
-		log.Warnf("Default polling strategy triggered inside selection. This should be rare.")
+		log.Warnf("Unknown polling strategy '%s'. Using sequential as fallback.", pool.PollingStrategy)
 		sequentialKey := fmt.Sprintf(BasePoolSequential, poolID)
-		keyIDStr, err = r.store.LIndex(ctx, sequentialKey, 0)
+		keyIDStr, err = r.store.Rotate(ctx, sequentialKey)
 	}
-
 	if err != nil {
-		if errors.Is(err, store.ErrNotFound) {
+		if errors.Is(err, store.ErrNotFound) || errors.Is(err, gorm.ErrRecordNotFound) {
 			return nil, nil, gorm.ErrRecordNotFound
 		}
 		log.WithError(err).Errorf("Failed to select key from BasePool with strategy %s", pool.PollingStrategy)
@@ -122,118 +131,246 @@ func (r *gormKeyRepository) SelectOneActiveKeyFromBasePool(ctx context.Context,
 	if keyIDStr == "" {
 		return nil, nil, gorm.ErrRecordNotFound
 	}
-	keyID, _ := strconv.ParseUint(keyIDStr, 10, 64)
-
-	for _, group := range pool.CandidateGroups {
-		apiKey, mapping, cacheErr := r.getKeyDetailsFromCache(ctx, uint(keyID), group.ID)
-		if cacheErr == nil && apiKey != nil && mapping != nil {
-			if pool.PollingStrategy == models.StrategyWeighted {
-				go r.updateKeyUsageTimestampForPool(context.Background(), poolID, uint(keyID))
-			}
-			return apiKey, group, nil
+	go func() {
+		bgCtx, cancel := r.withTimeout(5 * time.Second)
+		defer cancel()
+		r.refreshBasePoolHeartbeat(bgCtx, poolID)
+	}()
+	keyID, parseErr := strconv.ParseUint(keyIDStr, 10, 64)
+	if parseErr != nil {
+		log.WithError(parseErr).Errorf("Invalid key ID format in BasePool cache: %s", keyIDStr)
+		return nil, nil, fmt.Errorf("invalid key ID in cache: %w", parseErr)
+	}
+	keyToGroupMapKey := fmt.Sprintf("basepool:%s:key_to_group", poolID)
+	groupIDStr, err := r.store.HGet(ctx, keyToGroupMapKey, keyIDStr)
+	if err != nil {
+		log.WithError(err).Errorf("Cache inconsistency: KeyID %d found in pool but not in key-to-group map", keyID)
+		return nil, nil, errors.New("cache inconsistency: key has no origin group mapping")
+	}
+	groupID, parseErr := strconv.ParseUint(groupIDStr, 10, 64)
+	if parseErr != nil {
+		log.WithError(parseErr).Errorf("Invalid group ID format in key-to-group map for key %d: %s", keyID, groupIDStr)
+		return nil, nil, errors.New("cache inconsistency: invalid group id in mapping")
+	}
+	apiKey, _, err := r.getKeyDetailsFromCache(ctx, uint(keyID), uint(groupID))
+	if err != nil {
+		log.WithError(err).Warnf("Cache inconsistency: Failed to get details for key %d in mapped group %d", keyID, groupID)
+		return nil, nil, err
+	}
+	var originGroup *models.KeyGroup
+	for _, g := range pool.CandidateGroups {
+		if g.ID == uint(groupID) {
+			originGroup = g
+			break
 		}
 	}
-
-	log.Errorf("Cache inconsistency: Selected KeyID %d from BasePool but could not find its origin group.", keyID)
-	return nil, nil, errors.New("cache inconsistency: selected key has no origin group")
+	if originGroup == nil {
+		log.Errorf("Logic error: Mapped GroupID %d not found in pool's candidate groups list", groupID)
+		return nil, nil, errors.New("cache inconsistency: mapped group not in candidate list")
+	}
+	if pool.PollingStrategy == models.StrategyWeighted {
+		go func() {
+			bgCtx, cancel := r.withTimeout(5 * time.Second)
+			defer cancel()
+			r.updateKeyUsageTimestampForPool(bgCtx, poolID, uint(keyID))
+		}()
+	}
+	return apiKey, originGroup, nil
 }
 
-// ensureBasePoolCacheExists 动态创建 BasePool 的 Redis 结构
+// ensureBasePoolCacheExists 动态创建或验证 BasePool 的 Redis 缓存结构。
 func (r *gormKeyRepository) ensureBasePoolCacheExists(ctx context.Context, pool *BasePool, poolID string) error {
-	listKey := fmt.Sprintf(BasePoolSequential, poolID)
-
-	exists, err := r.store.Exists(ctx, listKey)
-	if err != nil {
-		r.logger.WithError(err).Errorf("Failed to check existence for pool_id '%s'", poolID)
-		return err
+	heartbeatKey := fmt.Sprintf("basepool:%s:heartbeat", poolID)
+	emptyMarkerKey := fmt.Sprintf("basepool:empty:%s", poolID)
+	// 预检查，快速失败
+	if exists, _ := r.store.Exists(ctx, emptyMarkerKey); exists {
+		return gorm.ErrRecordNotFound
 	}
-	if exists {
-		val, err := r.store.LIndex(ctx, listKey, 0)
-		if err != nil {
-			r.logger.WithError(err).Warnf("Cache for pool_id '%s' exists but is unreadable. Forcing rebuild.", poolID)
-		} else {
-			if val == EmptyPoolPlaceholder {
-				return gorm.ErrRecordNotFound
-			}
-			return nil
-		}
-	}
-
-	lockKey := fmt.Sprintf("lock:basepool:%s", poolID)
-	acquired, err := r.store.SetNX(ctx, lockKey, []byte("1"), 10*time.Second)
-	if err != nil {
-		r.logger.WithError(err).Error("Failed to attempt acquiring distributed lock for basepool build.")
-		return err
-	}
-	if !acquired {
-		time.Sleep(100 * time.Millisecond)
-		return r.ensureBasePoolCacheExists(ctx, pool, poolID)
-	}
-	defer r.store.Del(context.Background(), lockKey)
-
-	if exists, _ := r.store.Exists(ctx, listKey); exists {
+	if exists, _ := r.store.Exists(ctx, heartbeatKey); exists {
 		return nil
 	}
-	r.logger.Infof("BasePool cache for pool_id '%s' not found or is unreadable. Building now...", poolID)
-	var allActiveKeyIDs []string
-	lruMembers := make(map[string]float64)
+	// 获取分布式锁
+	lockKey := fmt.Sprintf("lock:basepool:%s", poolID)
+	if err := r.acquireLock(ctx, lockKey); err != nil {
+		return err // acquireLock 内部已记录日志并返回明确错误
+	}
+	defer r.releaseLock(context.Background(), lockKey)
+	// 双重检查锁定
+	if exists, _ := r.store.Exists(ctx, emptyMarkerKey); exists {
+		return gorm.ErrRecordNotFound
+	}
+	if exists, _ := r.store.Exists(ctx, heartbeatKey); exists {
+		return nil
+	}
+	// 在执行重度操作前，最后检查一次上下文是否已取消
+	select {
+	case <-ctx.Done():
+		return ctx.Err()
+	default:
+	}
+	r.logger.Infof("Building BasePool cache for pool_id '%s'", poolID)
+	// 手动聚合所有 Keys 并同时构建 key-to-group 映射
+	keyToGroupMap := make(map[string]any)
+	allKeyIDsSet := make(map[string]struct{})
 	for _, group := range pool.CandidateGroups {
-		activeKeySetKey := fmt.Sprintf(KeyGroup, group.ID)
-		groupKeyIDs, err := r.store.SMembers(ctx, activeKeySetKey)
+		groupKeySet := fmt.Sprintf(KeyGroup, group.ID)
+		groupKeyIDs, err := r.store.SMembers(ctx, groupKeySet)
 		if err != nil {
-			r.logger.WithError(err).Errorf("FATAL: Failed to read active keys for group %d during BasePool build. Aborting build process for pool_id '%s'.", group.ID, poolID)
-			return err
+			r.logger.WithError(err).Warnf("Failed to get members for group %d during pool build", group.ID)
+			continue
 		}
-		allActiveKeyIDs = append(allActiveKeyIDs, groupKeyIDs...)
-		for _, keyIDStr := range groupKeyIDs {
-			keyID, _ := strconv.ParseUint(keyIDStr, 10, 64)
-			_, mapping, err := r.getKeyDetailsFromCache(ctx, uint(keyID), group.ID)
-			if err == nil && mapping != nil {
-				var score float64
-				if mapping.LastUsedAt != nil {
-					score = float64(mapping.LastUsedAt.UnixMilli())
-				}
-				lruMembers[keyIDStr] = score
+		groupIDStr := strconv.FormatUint(uint64(group.ID), 10)
+		for _, keyID := range groupKeyIDs {
+			if _, exists := allKeyIDsSet[keyID]; !exists {
+				allKeyIDsSet[keyID] = struct{}{}
+				keyToGroupMap[keyID] = groupIDStr
 			}
 		}
 	}
-
-	if len(allActiveKeyIDs) == 0 {
-		r.logger.Warnf("No active keys found for any candidate groups for pool_id '%s'. Setting empty pool placeholder.", poolID)
-		pipe := r.store.Pipeline(ctx)
-		pipe.LPush(listKey, EmptyPoolPlaceholder)
-		pipe.Expire(listKey, EmptyCacheTTL)
-		if err := pipe.Exec(); err != nil {
-			r.logger.WithError(err).Errorf("Failed to set empty pool placeholder for pool_id '%s'", poolID)
+	// 处理空池情况
+	if len(allKeyIDsSet) == 0 {
+		emptyCacheTTL := time.Duration(r.config.Repository.BasePoolTTIMinutes) * time.Minute / 2
+		if emptyCacheTTL < time.Minute {
+			emptyCacheTTL = time.Minute
+		}
+		r.logger.Warnf("No active keys found for pool_id '%s', setting empty marker.", poolID)
+		if err := r.store.Set(ctx, emptyMarkerKey, []byte("1"), emptyCacheTTL); err != nil {
+			r.logger.WithError(err).Warnf("Failed to set empty marker for pool_id '%s'", poolID)
 		}
 		return gorm.ErrRecordNotFound
 	}
-
+	allActiveKeyIDs := make([]string, 0, len(allKeyIDsSet))
+	for keyID := range allKeyIDsSet {
+		allActiveKeyIDs = append(allActiveKeyIDs, keyID)
+	}
+	// 使用 Pipeline 原子化构建所有缓存结构
+	basePoolTTL := time.Duration(r.config.Repository.BasePoolTTLMinutes) * time.Minute
+	basePoolTTI := time.Duration(r.config.Repository.BasePoolTTIMinutes) * time.Minute
+	mainPoolKey := fmt.Sprintf(BasePoolRandomMain, poolID)
+	sequentialKey := fmt.Sprintf(BasePoolSequential, poolID)
+	cooldownKey := fmt.Sprintf(BasePoolRandomCooldown, poolID)
+	lruKey := fmt.Sprintf(BasePoolLRU, poolID)
+	keyToGroupMapKey := fmt.Sprintf("basepool:%s:key_to_group", poolID)
 	pipe := r.store.Pipeline(ctx)
-	pipe.LPush(fmt.Sprintf(BasePoolSequential, poolID), toInterfaceSlice(allActiveKeyIDs)...)
-	pipe.SAdd(fmt.Sprintf(BasePoolRandomMain, poolID), toInterfaceSlice(allActiveKeyIDs)...)
-	pipe.Expire(fmt.Sprintf(BasePoolSequential, poolID), CacheTTL)
-	pipe.Expire(fmt.Sprintf(BasePoolRandomMain, poolID), CacheTTL)
-	pipe.Expire(fmt.Sprintf(BasePoolRandomCooldown, poolID), CacheTTL)
-	pipe.Expire(fmt.Sprintf(BasePoolLRU, poolID), CacheTTL)
-
+	pipe.Del(mainPoolKey, sequentialKey, cooldownKey, lruKey, emptyMarkerKey, keyToGroupMapKey)
+	pipe.SAdd(mainPoolKey, r.toInterfaceSlice(allActiveKeyIDs)...)
+	pipe.LPush(sequentialKey, r.toInterfaceSlice(allActiveKeyIDs)...)
+	if len(keyToGroupMap) > 0 {
+		pipe.HSet(keyToGroupMapKey, keyToGroupMap)
+		pipe.Expire(keyToGroupMapKey, basePoolTTL)
+	}
+	pipe.Expire(mainPoolKey, basePoolTTL)
+	pipe.Expire(sequentialKey, basePoolTTL)
+	pipe.Expire(cooldownKey, basePoolTTL)
+	pipe.Expire(lruKey, basePoolTTL)
+	pipe.Set(heartbeatKey, []byte("1"), basePoolTTI)
 	if err := pipe.Exec(); err != nil {
+		r.logger.WithError(err).Errorf("Failed to populate polling structures for pool_id '%s'", poolID)
+		cleanupCtx, cancel := r.withTimeout(5 * time.Second)
+		defer cancel()
+		r.store.Del(cleanupCtx, mainPoolKey, sequentialKey, cooldownKey, lruKey, heartbeatKey, emptyMarkerKey, keyToGroupMapKey)
 		return err
 	}
+	// 异步填充 LRU 缓存，并传入已构建好的映射
+	go r.populateBasePoolLRUCache(context.Background(), poolID, allActiveKeyIDs, keyToGroupMap)
+	return nil
+}
 
-	if len(lruMembers) > 0 {
-		if err := r.store.ZAdd(ctx, fmt.Sprintf(BasePoolLRU, poolID), lruMembers); err != nil {
-			r.logger.WithError(err).Warnf("Failed to populate LRU cache for pool_id '%s'", poolID)
+// --- 辅助方法 ---
+// acquireLock 封装了带重试和指数退避的分布式锁获取逻辑。
+func (r *gormKeyRepository) acquireLock(ctx context.Context, lockKey string) error {
+	const (
+		lockTTL         = 30 * time.Second
+		lockMaxRetries  = 5
+		lockBaseBackoff = 50 * time.Millisecond
+	)
+	for i := 0; i < lockMaxRetries; i++ {
+		acquired, err := r.store.SetNX(ctx, lockKey, []byte("1"), lockTTL)
+		if err != nil {
+			r.logger.WithError(err).Error("Failed to attempt acquiring distributed lock")
+			return err
+		}
+		if acquired {
+			return nil
+		}
+		time.Sleep(lockBaseBackoff * (1 << i))
+	}
+	return fmt.Errorf("failed to acquire lock for key '%s' after %d retries", lockKey, lockMaxRetries)
+}
+
+// releaseLock 封装了分布式锁的释放逻辑。
+func (r *gormKeyRepository) releaseLock(ctx context.Context, lockKey string) {
+	if err := r.store.Del(ctx, lockKey); err != nil {
+		r.logger.WithError(err).Errorf("Failed to release distributed lock for key '%s'", lockKey)
+	}
+}
+
+// withTimeout 是 context.WithTimeout 的一个简单包装，便于测试和模拟。
+func (r *gormKeyRepository) withTimeout(duration time.Duration) (context.Context, context.CancelFunc) {
+	return context.WithTimeout(context.Background(), duration)
+}
+
+// refreshBasePoolHeartbeat 异步刷新心跳Key的TTI
+func (r *gormKeyRepository) refreshBasePoolHeartbeat(ctx context.Context, poolID string) {
+	basePoolTTI := time.Duration(r.config.Repository.BasePoolTTIMinutes) * time.Minute
+	heartbeatKey := fmt.Sprintf("basepool:%s:heartbeat", poolID)
+	// 使用 EXPIRE 命令来刷新，如果Key不存在，它什么也不做，是安全的
+	if err := r.store.Expire(ctx, heartbeatKey, basePoolTTI); err != nil {
+		if ctx.Err() == nil { // 避免在context取消后打印不必要的错误
+			r.logger.WithError(err).Warnf("Failed to refresh heartbeat for pool_id '%s'", poolID)
+		}
+	}
+}
+
+// populateBasePoolLRUCache 异步填充 BasePool 的 LRU 缓存结构
+func (r *gormKeyRepository) populateBasePoolLRUCache(
+	parentCtx context.Context,
+	currentPoolID string,
+	keys []string,
+	keyToGroupMap map[string]any,
+) {
+	lruMembers := make(map[string]float64, len(keys))
+	for _, keyIDStr := range keys {
+		select {
+		case <-parentCtx.Done():
+			return
+		default:
+		}
+		groupIDStr, ok := keyToGroupMap[keyIDStr].(string)
+		if !ok {
+			continue
+		}
+		keyID, _ := strconv.ParseUint(keyIDStr, 10, 64)
+		groupID, _ := strconv.ParseUint(groupIDStr, 10, 64)
+		mappingKey := fmt.Sprintf(KeyMapping, groupID, keyID)
+		data, err := r.store.Get(parentCtx, mappingKey)
+		if err != nil {
+			continue
+		}
+		var mapping models.GroupAPIKeyMapping
+		if json.Unmarshal(data, &mapping) == nil {
+			var score float64
+			if mapping.LastUsedAt != nil {
+				score = float64(mapping.LastUsedAt.UnixMilli())
+			}
+			lruMembers[keyIDStr] = score
+		}
+	}
+	if len(lruMembers) > 0 {
+		lruKey := fmt.Sprintf(BasePoolLRU, currentPoolID)
+		if err := r.store.ZAdd(parentCtx, lruKey, lruMembers); err != nil {
+			if parentCtx.Err() == nil {
+				r.logger.WithError(err).Warnf("Failed to populate LRU cache for pool '%s'", currentPoolID)
+			}
 		}
 	}
-	return nil
 }
 
 // updateKeyUsageTimestampForPool 更新 BasePool 的 LUR ZSET
 func (r *gormKeyRepository) updateKeyUsageTimestampForPool(ctx context.Context, poolID string, keyID uint) {
 	lruKey := fmt.Sprintf(BasePoolLRU, poolID)
 	err := r.store.ZAdd(ctx, lruKey, map[string]float64{
-		strconv.FormatUint(uint64(keyID), 10): nowMilli(),
+		strconv.FormatUint(uint64(keyID), 10): r.nowMilli(),
 	})
 	if err != nil {
 		r.logger.WithError(err).Warnf("Failed to update key usage for pool %s", poolID)
@@ -241,20 +378,19 @@ func (r *gormKeyRepository) updateKeyUsageTimestampForPool(ctx context.Context,
 }
 
 // generatePoolID 根据候选组ID列表生成一个稳定的、唯一的字符串ID
-func generatePoolID(groups []*models.KeyGroup) string {
+func (r *gormKeyRepository) generatePoolID(groups []*models.KeyGroup) string {
 	ids := make([]int, len(groups))
 	for i, g := range groups {
 		ids[i] = int(g.ID)
 	}
 	sort.Ints(ids)
-
 	h := sha1.New()
 	io.WriteString(h, fmt.Sprintf("%v", ids))
 	return fmt.Sprintf("%x", h.Sum(nil))
 }
 
 // toInterfaceSlice 类型转换辅助函数
-func toInterfaceSlice(slice []string) []interface{} {
+func (r *gormKeyRepository) toInterfaceSlice(slice []string) []interface{} {
 	result := make([]interface{}, len(slice))
 	for i, v := range slice {
 		result[i] = v
@@ -263,7 +399,7 @@ func toInterfaceSlice(slice []string) []interface{} {
 }
 
 // nowMilli 返回当前的Unix毫秒时间戳，用于LRU/Weighted策略
-func nowMilli() float64 {
+func (r *gormKeyRepository) nowMilli() float64 {
 	return float64(time.Now().UnixMilli())
 }