fix(redis): 添加Redis缓存模块导入异常处理

src/common/database/optimization/__init__.py

@@ -33,7 +33,6 @@ from .preloader import (
     get_preloader,
     record_preload_access,
 )
-from .redis_cache import RedisCache, close_redis_cache, get_redis_cache
 
 __all__ = [
     "AccessPattern",
@@ -53,16 +52,12 @@ __all__ = [
     # Memory Cache
     "MultiLevelCache",
     "Priority",
-    # Redis Cache
-    "RedisCache",
     "close_batch_scheduler",
     "close_cache",
     "close_preloader",
-    "close_redis_cache",
     "get_batch_scheduler",
     "get_cache",
     "get_cache_backend_type",
     "get_preloader",
     "record_preload_access",
-    "get_redis_cache"
 ]

src/common/database/optimization/cache_manager.py

@@ -887,7 +887,12 @@ async def _create_redis_cache(db_config: Any) -> CacheBackend:
     Raises:
         RuntimeError: Redis 连接失败时抛出异常
     """
-    from src.common.database.optimization.redis_cache import RedisCache
+    try:
+        from src.common.database.optimization.redis_cache import RedisCache
+    except ModuleNotFoundError as exc:
+        raise RuntimeError(
+            "Redis 缓存后端需要可选依赖 'redis'，请执行 `pip install redis` 或将 cache_backend 配置为 'memory'"
+        ) from exc
 
     logger.info(
         f"创建 Redis 缓存: {db_config.redis_host}:{db_config.redis_port}/{db_config.redis_db}, "