Python 使用Django rest框架从2个不同的表中筛选

您好，我正在尝试从两个具有一对多关系的不同表中筛选数据

我有产品表和规格表。1产品涉及多个规格清单。我在获取包括规格在内的所有产品信息方面没有任何问题。我还成功地筛选了产品表，如按类别和制造商筛选。但我想在过滤类别/制造商时也基于规范进行过滤

这是我的模型

class Products(models.Model):
    product_partnumber = models.CharField(max_length=255)
    image_link = models.URLField(default=None, blank=True, null=True)
    pdf_link = models.URLField()
    manufacturer = models.ForeignKey(Manufacturer, on_delete=models.CASCADE)
    category = models.ForeignKey(Category, on_delete=models.CASCADE)
    subcategory = models.ForeignKey(Subcategory, on_delete=models.CASCADE)
    created_at = models.DateTimeField(auto_now_add=True)

    class Meta:
        verbose_name_plural = 'Products'

class ProductSpecification(models.Model):
    product = models.ForeignKey(Products, related_name='specifications', on_delete=models.CASCADE)
    specification = models.ForeignKey(Specification, related_name='specification_name', on_delete=models.CASCADE)
    value = models.CharField(max_length=255)
    created_at = models.DateTimeField(auto_now_add=True)

这是我的api和过滤代码。到目前为止，我只在一个表上成功过滤。我不知道如何在过滤器类中添加ProductSpecification模型

class NumberInFilter(filters.BaseInFilter, filters.NumberFilter):
    pass

class ProductFilter(filters.FilterSet):
    manufacturer__in = NumberInFilter(field_name='manufacturer', lookup_expr='in')

    class Meta:
        model = Products
        fields = ['category', 'product_partnumber']

class ProductsView(viewsets.ModelViewSet):
    queryset = Products.objects.all()
    serializer_class = ProductsSerializers
    filter_backends = [filters.DjangoFilterBackend]
    filterset_class = ProductFilter

    def create(self, request, *args, **kwargs):
        many = True if isinstance(request.data, list) else False
        serializer = ProductsSerializers(data=request.data, many=many)
        if serializer.is_valid():
            serializer.save()
            product=serializer.data
        else:
            return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
        return Response(product, status=status.HTTP_201_CREATED)

class SpecificationView(viewsets.ModelViewSet):
    queryset = Specification.objects.all()
    serializer_class = SpecificationSerializers

    def create(self, request, *args, **kwargs):
        many = True if isinstance(request.data, list) else False
        serializer = SpecificationSerializers(data=request.data, many=many)
        if serializer.is_valid():
            serializer.save()
        else:
            return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
        return Response(serializer.data, status=status.HTTP_201_CREATED)
    
class ProductSpecificationView(viewsets.ModelViewSet):
    queryset = ProductSpecification.objects.all()
    serializer_class = ProductSpecificationSerializers

    def create(self, request, *args, **kwargs):
        many = True if isinstance(request.data, list) else False
        serializer = ProductSpecificationSerializers(data=request.data, many=many)
        if serializer.is_valid():
            serializer.save()
        else:
            return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
        return Response(serializer.data, status=status.HTTP_201_CREATED)

我想选择product.category等于$val1、productspecification.specification=$val2、productspecification.value=$val3的产品的所有数据。但即使我只在1个规格上使用过滤器，如果一个产品有3个规格，我仍然希望获得所有这些数据

这是我获取的产品数据的格式，这仍然是我希望使用过滤器接收的数据格式

{
  "id": 1,
  "product_partnumber": "SSPA 1.2-1.4-800-RM",
  "image_link": "https://www.aethercomm.com/wp-content/uploads/2019/05/SSPA-1.2-1.4-800-RM-300x112.png",
  "pdf_link": "https://www.aethercomm.com/wp-content/uploads/2019/05/Data-Sheet_SSPA-1.2-1.4-800-RM.pdf",
  "manufacturer": 1,
  "manufacturer_details": {
    "id": 1,
    "name": "Aethercomm",
    "url": "https://www.aethercomm.com/",
    "created_at": "2020-09-08T03:48:34.200963Z"
  },
  "category": 2,
  "category_details": {
    "id": 2,
    "name": "Amplifier",
    "created_at": "2020-09-09T16:17:56.777422Z"
  },
  "subcategory": 45,
  "specifications": [
    {
      "specification": 2,
      "specification_details": {
        "id": 2,
        "name": "Frequency (min/max)",
        "created_at": "2020-09-09T16:15:33.428022Z"
      },
      "value": "1200/1400"
    },
    {
      "specification": 1,
      "specification_details": {
        "id": 1,
        "name": "Description",
        "created_at": "2020-09-09T16:15:33.301119Z"
      },
      "value": "High Power L Band Radar Pulsed Amplifier 800 Watts typical Peak Output Power 50 dB typ gain Typical Pulse Width is 100uSec to 1000 uSec Typical Duty Cycle is 10%"
    }
  ]
}

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抱歉发了这么长的邮件，提前谢谢。干杯

你试过这样的方法吗：

Products.objects.filter（category=$val1，specifications.specification=$val2，specifications.value=$val3）

---

我不知道你对最后一个的意思是什么：但即使我只对1种规格使用过滤器，如果一个产品有3种规格，我仍然希望获得所有这些数据。

谢谢你的回复。有没有一种方法可以让我修改现有的过滤代码来实现这一点？谢谢