Django Rest Framework Serializer 不想接受返回的列表，并且 returns AttributeError 'str' 对象没有属性 'x'

Question

所以我试图将颜色列表和 return 查询集聚合到序列化程序，但是序列化程序似乎出于某种原因不接受这个。

当运行 shell 中的命令时，我得到：

>>> from django.contrib.postgres.aggregates import ArrayAgg
>>> from inventory.models import Product
>>> products = Product.objects.filter(category__parent__name__iexact='fliser').distinct().aggregate(colors_field=ArrayAgg('colors__name'))
>>> print(products)
{'colors_field': ['Beige', 'Grå', 'Hvit', 'Sort', 'Beige', 'Gul', 'Rød']}

这是预期的结果。

序列化器的结构如下：

class ProductFiltersByCategorySerializer(serializers.ModelSerializer):
    """
    A serializer to display available filters for a product lust 
    """

    colors = serializers.StringRelatedField(read_only=True, many=True)

    class Meta:
        model = Product
        fields = ['colors']

视图集如下所示：

class ProductFiltersByCategory(generics.ListAPIView):
    """
    This viewset takes the category parameter from the url and returns related product filters
    """

    serializer_class = ProductFiltersByCategorySerializer

    def get_queryset(self):
        category = self.kwargs['category']
        queryset = Product.objects.filter(category__parent__name__iexact=category).distinct().aggregate(colors_field=ArrayAgg('colors__name'))
        return queryset

模型的相关部分如下所示：

class Product(models.Model):

    ...
    colors = models.ManyToManyField(
        ProductColor,
        related_name='product_color'
    )
    ...

尝试访问端点时的错误是 'str' object has no attribute 'colors'。

期望输出：

[
    {
        "colors": [
            "Red",
            "Orange",
        ],
    },
]

Answer 1

这里不需要ListAPIViewclass，使用APIView 作为

from rest_framework.views import APIView
from rest_framework.response import Response


class MyAPIView(APIView):
    def get(self, request, *args, **kwargs):
        category = kwargs['category']
        agg_result = Product.objects.filter(
            category__parent__name__iexact=category
        ).distinct().aggregate(colors_field=ArrayAgg('colors__name'))
        return Response(agg_result)

Answer 2

class ProductColorSerializer(serializers.ModelSerializer):
    class Meta:
        model = ProductColor
        fields = '__all__'

class ProductFiltersByCategorySerializer(serializers.ModelSerializer):
    """
    A serializer to display available filters for a product lust 
    """

    product_color = ProductColorSerializer(many=True)

    class Meta:
        model = Product
        fields = ['product_color']

Django Rest Framework Serializer 不想接受返回的列表，并且 returns AttributeError 'str' 对象没有属性 'x'

Django Rest Framework Serializer do not want to accept returned list, and returns AttributeError 'str' object has no attribute 'x'

python

django

django-serializer

django-rest-framework