feat: sse && multi_merchant completed

api_v1/views/inventory.py

@@ -0,0 +1,176 @@
+from rest_framework.generics import GenericAPIView
+from rest_framework.mixins import ListModelMixin
+from rest_framework.response import Response
+from rest_framework.permissions import IsAuthenticated
+from rest_framework import serializers, status
+from rest_framework.pagination import LimitOffsetPagination
+from stock import models as stock_models
+from basic_info import models as basic_models
+from api_man.serializers import ProductSerializer
+import logging
+
+logger = logging.getLogger(__name__)
+
+
+class WarehouseSimpleSerializer(serializers.ModelSerializer):
+    """仓库简单序列化器"""
+    
+    class Meta:
+        model = basic_models.WareHouse
+        fields = ['id', 'name', 'location', 'area']
+
+
+class InventorySerializer(serializers.ModelSerializer):
+    """库存项序列化器"""
+    product = ProductSerializer(read_only=True)
+    warehouse = WarehouseSimpleSerializer(read_only=True)
+    
+    class Meta:
+        model = stock_models.Inventory
+        fields = [
+            'id',
+            'product',
+            'warehouse',
+            'quantity',
+            'num_of_rolls',
+            'spec',
+        ]
+    
+    def __init__(self, *args, **kwargs):
+        """重写初始化方法，确保 context 传递给嵌套序列化器"""
+        super().__init__(*args, **kwargs)
+        # 如果有 context，将其传递给嵌套的序列化器字段
+        if hasattr(self, 'context'):
+            for field_name, field in self.fields.items():
+                if isinstance(field, serializers.ModelSerializer):
+                    field.context.update(self.context)
+
+
+class InventoryAPIView(ListModelMixin, GenericAPIView):
+    """
+    库存查询接口
+    
+    只返回当前用户所属商户的库存信息
+    
+    查询参数:
+    - limit: 返回的记录数量，默认20，最大100
+    - offset: 跳过的记录数量，默认0
+    - warehouse: 仓库ID，可选
+    - product: 产品ID，可选
+    
+    示例:
+    - /api/v1/inventory/ - 获取前20条
+    - /api/v1/inventory/?limit=50&offset=0 - 获取前50条
+    - /api/v1/inventory/?limit=20&offset=40 - 跳过前40条，获取接下来的20条
+    """
+    serializer_class = InventorySerializer
+    pagination_class = LimitOffsetPagination
+    permission_classes = [IsAuthenticated]
+    
+    def get_queryset(self):
+        """
+        获取查询集，自动过滤当前用户所属商户的库存
+        """
+        # 检查用户是否有员工身份
+        if not hasattr(self.request.user, 'employee'):
+            logger.warning(f"用户 {self.request.user.username} 无员工信息，拒绝访问库存")
+            return stock_models.Inventory.objects.none()
+        
+        employee = self.request.user.employee
+        merchant_id = employee.merchant_id
+        
+        # 使用 select_related 优化查询，只查询当前商户的库存
+        queryset = stock_models.Inventory.objects.filter(
+            merchant_id=merchant_id
+        ).select_related(
+            'product',
+            'product__category',
+            'warehouse'
+        ).order_by('-quantity', 'product__name')
+        
+        # 可选过滤：按仓库
+        warehouse_id = self.request.query_params.get('warehouse')
+        if warehouse_id:
+            try:
+                warehouse_id = int(warehouse_id)
+                # 验证仓库属于当前商户
+                if basic_models.WareHouse.objects.filter(
+                    id=warehouse_id, 
+                    merchant_id=merchant_id
+                ).exists():
+                    queryset = queryset.filter(warehouse_id=warehouse_id)
+                else:
+                    logger.warning(f"仓库ID {warehouse_id} 不属于商户 {merchant_id}")
+                    return queryset.none()
+            except ValueError:
+                logger.warning(f"warehouse 参数格式错误: {warehouse_id}")
+                return queryset.none()
+        
+        # 可选过滤：按产品
+        product_id = self.request.query_params.get('product')
+        if product_id:
+            try:
+                product_id = int(product_id)
+                # 验证产品属于当前商户
+                if basic_models.Product.objects.filter(
+                    id=product_id,
+                    merchant_id=merchant_id
+                ).exists():
+                    queryset = queryset.filter(product_id=product_id)
+                else:
+                    logger.warning(f"产品ID {product_id} 不属于商户 {merchant_id}")
+                    return queryset.none()
+            except ValueError:
+                logger.warning(f"product 参数格式错误: {product_id}")
+                return queryset.none()
+        
+        return queryset
+    
+    def get_serializer_context(self):
+        """
+        确保序列化器获得 request context
+        """
+        context = super().get_serializer_context()
+        context['request'] = self.request
+        return context
+    
+    def list(self, request, *args, **kwargs):
+        """
+        重写 list 方法，添加统计信息
+        """
+        queryset = self.filter_queryset(self.get_queryset())
+        
+        # 统计信息（在分页前）
+        total_items = queryset.count()
+        total_quantity = sum(item.quantity for item in queryset)
+        total_rolls = sum(item.num_of_rolls for item in queryset)
+        
+        # 使用 ListModelMixin 的分页和序列化逻辑
+        page = self.paginate_queryset(queryset)
+        if page is not None:
+            serializer = self.get_serializer(page, many=True)
+            response = self.get_paginated_response(serializer.data)
+            
+            # 添加统计信息
+            response.data['statistics'] = {
+                'total_items': total_items,
+                'total_quantity': float(total_quantity),
+                'total_rolls': total_rolls,
+            }
+            
+            logger.info(
+                f"用户 {request.user.username} 查询库存列表，"
+                f"商户ID: {request.user.employee.merchant_id}，共 {total_items} 条记录"
+            )
+            
+            return response
+        
+        # 如果没有分页，返回全部数据
+        serializer = self.get_serializer(queryset, many=True)
+        return Response(serializer.data)
+    
+    def get(self, request, *args, **kwargs):
+        """
+        GET 请求处理
+        """
+        return self.list(request, *args, **kwargs)