perf: 消除出库列表和还库操作的 N+1 查询，改用批量 IN + joinedload

inventory-backend/app/services/trans_service.py

@@ -114,12 +114,12 @@ class TransService:
     @staticmethod
     def process_return(data, operator_name):
         """
-        还库逻辑（支持部分归还）：
-        1. 校验本次归还数量不能大于待还数量
-        2. 恢复可用库存（按本次归还数量）
-        3. 更新库位 (如果有变动)
-        4. 记录库管签字
-        5. 更新归还数量和状态（部分归还/全部归还）
+        还库逻辑（支持部分归还）- 已优化，消除 N+1 和长事务死锁风险
+        四步走策略：
+        1. 收集所有 borrow_id
+        2. 批量锁定借用记录
+        3. 收集库存ID并批量锁定库存
+        4. 内存中完成业务逻辑
         """
         items = data.get('items', [])
         signature = data.get('signature_path')  # 库管签字
@@ -130,15 +130,60 @@ class TransService:
         model_map = {'stock_buy': StockBuy, 'stock_semi': StockSemi, 'stock_product': StockProduct}
 
         try:
+            # ==========================================
+            # ★ 优化步骤 1：收集所有 borrow_id
+            # ==========================================
+            borrow_ids = []
+            item_map = {}  # 存储原始 item 数据，key=borrow_id
             for item in items:
                 borrow_id = item.get('id')
-                # 前端传入的本次归还数量
-                return_qty = float(item.get('return_qty', 0))
-                # 前端如果没有填 return_location，应该在提交前处理好，或者这里做 fallback
-                # 这里假设前端传来的 return_location 就是最终要保存的库位
-                final_location = item.get('return_location')
+                if borrow_id:
+                    borrow_ids.append(borrow_id)
+                    item_map[borrow_id] = {
+                        'return_qty': float(item.get('return_qty', 0)),
+                        'final_location': item.get('return_location')
+                    }
 
-                record = TransBorrow.query.with_for_update().get(borrow_id)
+            if not borrow_ids:
+                raise ValueError("没有有效的归还记录")
+
+            # ==========================================
+            # ★ 优化步骤 2：批量锁定借用记录
+            # ==========================================
+            borrow_records = TransBorrow.query.with_for_update().filter(
+                TransBorrow.id.in_(borrow_ids)
+            ).all()
+
+            borrow_map = {r.id: r for r in borrow_records}
+
+            # ==========================================
+            # ★ 优化步骤 3：收集库存ID并批量锁定库存
+            # ==========================================
+            stock_ids_by_table = {'stock_buy': set(), 'stock_semi': set(), 'stock_product': set()}
+
+            for borrow_id, record in borrow_map.items():
+                if record.source_table in stock_ids_by_table and record.stock_id:
+                    stock_ids_by_table[record.source_table].add(record.stock_id)
+
+            stock_map = {}  # 格式: { ('stock_buy', 101): stock_obj }
+            for table_name, ids in stock_ids_by_table.items():
+                if not ids:
+                    continue
+                ModelClass = model_map[table_name]
+                stocks = ModelClass.query.with_for_update().filter(
+                    ModelClass.id.in_(ids)
+                ).all()
+                for stock in stocks:
+                    stock_map[(table_name, stock.id)] = stock
+
+            # ==========================================
+            # ★ 优化步骤 4：内存中完成业务逻辑
+            # ==========================================
+            for borrow_id, item_data in item_map.items():
+                return_qty = item_data['return_qty']
+                final_location = item_data['final_location']
+
+                record = borrow_map.get(borrow_id)
                 if not record:
                     continue
 
@@ -153,22 +198,19 @@ class TransService:
                 if return_qty > pending_qty:
                     raise ValueError(f"本次归还数量({return_qty})不能大于待还数量({pending_qty})")
 
-                ModelClass = model_map.get(record.source_table)
-                if ModelClass:
-                    stock = ModelClass.query.with_for_update().get(record.stock_id)
-                    if stock:
-                        # 1. 恢复可用库存（按本次归还数量）
-                        stock.available_quantity = float(stock.available_quantity) + return_qty
+                # 更新库存
+                stock = stock_map.get((record.source_table, record.stock_id))
+                if stock:
+                    # 恢复可用库存
+                    stock.available_quantity = float(stock.available_quantity) + return_qty
+                    # 更新库位
+                    if final_location:
+                        stock.warehouse_location = final_location
 
-                        # 2. 更新库位 (如果提供了有效值)
-                        if final_location:
-                            stock.warehouse_location = final_location
-
-                # 3. 更新归还数量
+                # 更新归还数量和状态
                 new_returned_qty = returned_qty + return_qty
                 record.returned_quantity = new_returned_qty
 
-                # 4. 更新状态
                 if new_returned_qty >= total_qty:
                     record.is_returned = True
                     record.status = 'returned'