style(backend): apply ruff format

apps/backend/utils/db_helpers.py

@@ -3,18 +3,16 @@
 
 提供统一的资源查询、权限验证等通用功能
 """
+
 from typing import TypeVar, Type, Optional, Any
 from sqlalchemy.orm import Session
 from fastapi import HTTPException, status
 
-T = TypeVar('T')
+T = TypeVar("T")
 
 
 def get_or_404(
-    model: Type[T],
-    model_id: int,
-    db: Session,
-    error_message: Optional[str] = None
+    model: Type[T], model_id: int, db: Session, error_message: Optional[str] = None
 ) -> T:
     """
     查询资源，不存在则抛出 404
@@ -35,18 +33,13 @@ def get_or_404(
     if not obj:
         default_message = f"{model.__name__}不存在"
         raise HTTPException(
-            status_code=status.HTTP_404_NOT_FOUND,
-            detail=error_message or default_message
+            status_code=status.HTTP_404_NOT_FOUND, detail=error_message or default_message
         )
     return obj
 
 
 def get_owned_or_403(
-    model: Type[T],
-    model_id: int,
-    user_id: int,
-    db: Session,
-    error_message: Optional[str] = None
+    model: Type[T], model_id: int, user_id: int, db: Session, error_message: Optional[str] = None
 ) -> T:
     """
     查询资源并验证归属，否则抛出 403
@@ -64,24 +57,19 @@ def get_owned_or_403(
     Raises:
         HTTPException: 403 无权访问此资源
     """
-    obj = db.query(model).filter(
-        model.id == model_id,
-        model.user_id == user_id
-    ).first()
+    obj = db.query(model).filter(model.id == model_id, model.user_id == user_id).first()
 
     if not obj:
         # 先检查资源是否存在
         exists = db.query(model).filter(model.id == model_id).first()
         if not exists:
             raise HTTPException(
-                status_code=status.HTTP_404_NOT_FOUND,
-                detail=f"{model.__name__}不存在"
+                status_code=status.HTTP_404_NOT_FOUND, detail=f"{model.__name__}不存在"
             )
         # 资源存在但不属于当前用户
         default_message = f"无权访问此{model.__name__}"
         raise HTTPException(
-            status_code=status.HTTP_403_FORBIDDEN,
-            detail=error_message or default_message
+            status_code=status.HTTP_403_FORBIDDEN, detail=error_message or default_message
         )
 
     return obj
@@ -92,7 +80,7 @@ def get_by_field_or_404(
     field_name: str,
     field_value: Any,
     db: Session,
-    error_message: Optional[str] = None
+    error_message: Optional[str] = None,
 ) -> T:
     """
     根据字段查询资源，不存在则抛出 404
@@ -110,14 +98,11 @@ def get_by_field_or_404(
     Raises:
         HTTPException: 404 资源不存在
     """
-    obj = db.query(model).filter(
-        getattr(model, field_name) == field_value
-    ).first()
+    obj = db.query(model).filter(getattr(model, field_name) == field_value).first()
 
     if not obj:
         default_message = f"{model.__name__}不存在"
         raise HTTPException(
-            status_code=status.HTTP_404_NOT_FOUND,
-            detail=error_message or default_message
+            status_code=status.HTTP_404_NOT_FOUND, detail=error_message or default_message
         )
     return obj