我想使用 ForeignKey 序列化器

Question

I have these Models Below


class Campaign(models.Model):
    title = models.CharField(max_length=120)
    img = models.ImageField(upload_to='products/')

    def __str__(self):
        return self.title
class Product(models.Model):
    title = models.CharField(max_length=100)
    data = models.DateField(auto_now_add=True)
    category = models.ForeignKey(Category, on_delete=models.CASCADE)
    image = models.ImageField(upload_to="products/")
    campaign = models.ForeignKey(Campaign, on_delete=models.DO_NOTHING, null=True, blank=True, related_name="products")
    offer = models.ForeignKey(Offer, on_delete=models.DO_NOTHING, null=True, blank=True)
    market_price = models.PositiveIntegerField()
    selling_price = models.PositiveIntegerField()
    description = models.TextField()

    def __str__(self):
        return self.title

我想展示campaign_wise 产品。但我找不到任何解决方案。虽然我尝试阅读 DRF 的文档

这是我的序列化器

class CampaignProductsSerializer(serializers.ModelSerializer):
    products = serializers.PrimaryKeyRelatedField(read_only=True, many=True)

    class Meta:
        model = Campaign
        fields = ['title', 'products']

Whenever i try to run this i get 'Product' object has no attribute 'products'

这是我的网址

path('campaign_products/<int:id>/', CampaignProducts.as_view()),

这是我的观点：

class CampaignProducts(APIView):
    def get(self, request, id):
        campaigns = Campaign.objects.all()
        query = Product.objects.filter(campaign_id = id)
        serializer = CampaignProductsSerializer(query, many=True)
        return Response(serializer.data)

Answer 1

在这种情况下，您应该制作两个序列化程序，一个用于Product，一个用于Campaign，所以：

class ProductSerializer(serializers.ModelSerializer):
    class Meta:
        model = Product
        fields = ['title']  # etc.


class CampaignProductsSerializer(serializers.ModelSerializer):
    products = ProductSerializer(read_only=True, many=True)

    class Meta:
        model = Campaign
        fields = ['title', 'products']

然后在视图中序列化一个Campaign:

from django.shortcuts import get_object_or_404

# returns the title of the campaign, and the products
class CampaignProducts(APIView):
    def get(self, request, id):
        campaign = get_object_or_404(Campaign, id=id)
        serializer = CampaignProductsSerializer(campaign)
        return Response(serializer.data)

如果您不想包含广告系列的数据，我们可以使用ProductSerializer：

# returns only the related products
class CampaignProducts(APIView):
    
    def get(self, request, id):
        products = Product.objects.filter(campaign_id=id)
        serializer = ProductSerializer(products, many=True)
        return Response({'data': serializer.data})