如何划分 JSON 字符串?

Question

>我有4个型号类别，供应商，位置，产品。供应商属于类别模型(供应商是类别的外键(。其余型号位于供应商(位置、产品(下

ProductSerializer 和 LocationSerializer 嵌套到 VendorSerializer，VendorSerializer 嵌套到CategorySerializer。

class ProductSerializer(WritableNestedModelSerializer):
class Meta:
model = Product
fields = ['id', 'item_name', 'price']
read_only_fields = ['id']
class LocationSerializer(WritableNestedModelSerializer):
class Meta:
model = Location
fields = ['place']
class VendorSerializer(WritableNestedModelSerializer):
vendor_location = LocationSerializer()
product = ProductSerializer(many=True)
class Meta:
model = Vendor
fields = ['vendor_name','vendor_location','product']
read_only_fields = ['id']
class CategorySerializer(WritableNestedModelSerializer):
vendor = VendorSerializer(many=True)
class Meta:
model = Category
fields = ['id', 'category_name', 'tittle', 'vendor']
read_only_fields = ['id']

# 查看

class ProductView(APIView):
permission_classes = [IsAuthenticated]
def get(self, request, format=None, *args, **kwargs):
products = Category.objects.all()
serializer = CategorySerializer(products, many=True, context={'request': request})
return Response({'response': 'ok', 'result': serializer.data})

# 输出

{
"response": "ok",
"result": [
{
"id": 1,
"category_name": "Cake",
"tittle": "test title",
"vendor": [                
{
"vendor_name": "Test_Name",
"vendor_location": {
"place": "Test_Place"
},
"product": [
{
"id": 1,
"item_name": "test_1",
"price": 3200,
},
{
"id": 2,
"item_name": "test_2",
"price": 2010,
}
]
}
]
}
]
}

# 预期输出

{
"response": "ok",
"result": [
{
"id": 1,
"category_name": "Cake",
"tittle": "test title",
"vendor": [                
{
"vendor_name": "Test_Name",
"vendor_location": {
"place": "Test_Place"
},
"product": [
{
"id": 1,
"item_name": "test_1",
"price": 3200,
}
]
}
]
},
{
"id": 1,
"category_name": "Cake",
"tittle": "test title",
"vendor": [                
{
"vendor_name": "Test_Name",
"vendor_location": {
"place": "Test_Place"
},
"product": [                  
{
"id": 2,
"item_name": "test_2",
"price": 2010,
}
]
}
]
}
]
}

在我的输出中，列出了两个产品。可能不止两个。我只需要产品下的一个产品。所有产品必须以与我在预期输出中提到的相同结构打印。我该怎么做？可能吗？有人可以帮我做到这一点吗？

Answer 1

您可以修改此行：

# old:
products = Category.objects.all()  # definately these are not products
# new:
products = Product.objects.values_list('id', flat=True)  # get all products ids
categories = Category.objects.filter(vendor__product__in=products)

并将categories发送给CategorySerializer，认为这仍然不是您想要的，因为每个重复的类别都将包含有关所有产品(而不仅仅是一个(的信息。
从现在开始，我会去哪里？我会在VendorSerializer中创建方法get_product，并以某种方式保存我们现在所处的Category/Vendor的信息，如果我们已经为此Category添加了Product- 我会跳过接下来添加。

附言。我仍然不明白为什么你需要这种格式。