feat: red flush and cost

api_v1/views/business/purchase/views.py

@@ -54,12 +54,14 @@ class PurchaseOrderSerializer(serializers.ModelSerializer):
             'total_amount', 'diff_quantity', 'total_quantity',
             'operator', 'operator_name', 'warehouse', 'warehouse_name',
             'status', 'is_red_flushed', 'red_flush_id', 'red_flushed_at',
+            'balance_before_snapshot',
             'remarks', 'created_at', 'updated_at', 'items', 'quantity_of_rolls',
         ]
         read_only_fields = [
             'id', 'created_at', 'updated_at', 'items', 'supplier_name',
             'operator_name', 'warehouse_name', 'is_red_flushed',
             'red_flush_id', 'red_flushed_at',
+            'balance_before_snapshot',
         ]
 
 
@@ -142,6 +144,7 @@ class PurchaseOrderView(StockChangeViewMixin, views.APIView):
                 'id': purchase_order.id,
                 'human_id': purchase_order.human_id,
                 'status': purchase_order.status,
+                'balance_before_snapshot': purchase_order.balance_before_snapshot,
                 'message': '采购单创建成功，等待审批',
             },
             status=status.HTTP_201_CREATED,