修复：消除托盘与用户分配查询竞态

shierfeng-fastapi-backend/module_business/dao/master_dao.py

@@ -2,12 +2,13 @@ from datetime import datetime
 from typing import Any, Literal
 
 from pydantic import BaseModel
-from sqlalchemy import ColumnElement, Select, delete, func, or_, select, update
+from sqlalchemy import ColumnElement, Select, and_, delete, func, or_, select, update
 from sqlalchemy.ext.asyncio import AsyncSession
 from sqlalchemy.orm.attributes import InstrumentedAttribute
 
 from common.vo import PageModel
 from module_admin.entity.do.user_do import SysUser
+from module_business.domain.enums import PalletFlowState
 from module_business.entity.do.master_do import (
     BizCustomer,
     BizCustomerSite,
@@ -20,10 +21,13 @@ from module_business.entity.do.master_do import (
 )
 from module_business.entity.do.operation_do import (
     BizFillingRecord,
+    BizInboundItem,
     BizInboundOrder,
     BizPalletEvent,
     BizPalletInventory,
+    BizReturnItem,
     BizReturnOrder,
+    BizShipmentItem,
     BizShipmentOrder,
     BizUsageRecord,
 )
@@ -74,6 +78,15 @@ _REFERENCE_COLUMNS: dict[MasterResource, tuple[tuple[InstrumentedAttribute, ...]
     ),
 }
 
+_PALLET_REMOVAL_BLOCKING_COLUMNS: tuple[InstrumentedAttribute, ...] = (
+    BizInboundItem.pallet_id,
+    BizFillingRecord.pallet_id,
+    BizShipmentItem.pallet_id,
+    BizUsageRecord.pallet_id,
+    BizReturnItem.pallet_id,
+    BizPalletEvent.pallet_id,
+)
+
 
 class MasterDao:
     """菌种、客户、现场、产线和仓库主数据数据库操作层。"""
@@ -99,8 +112,13 @@ class MasterDao:
         model: type[Any],
         id_column: InstrumentedAttribute,
         resource_id: int,
+        *,
+        for_update: bool = False,
     ) -> Any | None:
-        result = await db.execute(select(model).where(id_column == resource_id))
+        statement = select(model).where(id_column == resource_id)
+        if for_update:
+            statement = statement.with_for_update()
+        result = await db.execute(statement)
         return result.scalar_one_or_none()
 
     @staticmethod
@@ -245,8 +263,20 @@ class MasterDao:
         return await cls._paginate(db, statement, query_object, is_page)
 
     @classmethod
-    async def get_site(cls, db: AsyncSession, site_id: int) -> BizCustomerSite | None:
-        return await cls._get(db, BizCustomerSite, BizCustomerSite.site_id, site_id)
+    async def get_site(
+        cls,
+        db: AsyncSession,
+        site_id: int,
+        *,
+        for_update: bool = False,
+    ) -> BizCustomerSite | None:
+        return await cls._get(
+            db,
+            BizCustomerSite,
+            BizCustomerSite.site_id,
+            site_id,
+            for_update=for_update,
+        )
 
     @classmethod
     async def find_site_by_code(
@@ -343,8 +373,20 @@ class MasterDao:
         return await cls._paginate(db, statement, query_object, is_page)
 
     @classmethod
-    async def get_warehouse(cls, db: AsyncSession, warehouse_id: int) -> BizWarehouse | None:
-        return await cls._get(db, BizWarehouse, BizWarehouse.warehouse_id, warehouse_id)
+    async def get_warehouse(
+        cls,
+        db: AsyncSession,
+        warehouse_id: int,
+        *,
+        for_update: bool = False,
+    ) -> BizWarehouse | None:
+        return await cls._get(
+            db,
+            BizWarehouse,
+            BizWarehouse.warehouse_id,
+            warehouse_id,
+            for_update=for_update,
+        )
 
     @classmethod
     async def find_warehouse_by_code(cls, db: AsyncSession, warehouse_code: str) -> BizWarehouse | None:
@@ -391,6 +433,37 @@ class MasterDao:
         result = await db.execute(statement)
         return result.scalar_one_or_none()
 
+    @classmethod
+    async def get_pallet_removability(
+        cls,
+        db: AsyncSession,
+        pallet_ids: list[int],
+    ) -> dict[int, bool]:
+        """批量判断托盘是否仍为未入库且没有任何业务引用。"""
+        removability = dict.fromkeys(pallet_ids, False)
+        if not pallet_ids:
+            return removability
+
+        has_unstocked_inventory = (
+            select(BizPalletInventory.pallet_id)
+            .where(
+                BizPalletInventory.pallet_id == BizPallet.pallet_id,
+                BizPalletInventory.flow_state == PalletFlowState.UNSTOCKED.value,
+            )
+            .exists()
+        )
+        has_no_business_references = tuple(
+            ~select(column).where(column == BizPallet.pallet_id).exists() for column in _PALLET_REMOVAL_BLOCKING_COLUMNS
+        )
+        statement = select(
+            BizPallet.pallet_id,
+            and_(has_unstocked_inventory, *has_no_business_references).label('can_remove'),
+        ).where(BizPallet.pallet_id.in_(pallet_ids))
+        result = await db.execute(statement)
+        for pallet_id, can_remove in result.all():
+            removability[pallet_id] = bool(can_remove)
+        return removability
+
     @classmethod
     async def find_pallet_by_code(cls, db: AsyncSession, pallet_code: str) -> BizPallet | None:
         return await cls._find(db, BizPallet, BizPallet.pallet_code, pallet_code)
@@ -484,6 +557,16 @@ class MasterDao:
         )
         return list(result.all())
 
+    @classmethod
+    async def list_warehouse_assigned_user_ids(cls, db: AsyncSession, warehouse_id: int) -> list[int]:
+        result = await db.execute(select(BizUserWarehouse.user_id).where(BizUserWarehouse.warehouse_id == warehouse_id))
+        return list(result.scalars().all())
+
+    @classmethod
+    async def list_site_assigned_user_ids(cls, db: AsyncSession, site_id: int) -> list[int]:
+        result = await db.execute(select(BizUserSite.user_id).where(BizUserSite.site_id == site_id))
+        return list(result.scalars().all())
+
     @classmethod
     async def count_references(
         cls,