我需要显示与相同模型有多对多关系的相关字段。 Django Rest Frame工作

Posted 2021-05-06

我正在尝试创建一个相关的产品领域，我已经在模型中添加了多对多关系并将其设置为自我，因为我将手动选择相关产品。

class ProductsSerializer(serializers.ModelSerializer):

    images = ImagesSerializer(many=True)
    color = ColorSerializer(many=False)

    class Meta:
        fields = (
            'url',
            'id',
            "code",
            "sku",
            "title",
            "slug",
            "state",
            "old_price",
            "price",
            "valid",
            "in_stock",
            "category",
            "related_products",
            "color",
            "images",
            "video",
            "description",
            "fabric",
            "model_size_info",
        )
        model = Products

我不能引用相同的Serializer我需要在api json中获取产品详细信息。我找不到办法做到这一点。

感谢您提前帮助。

答案

方法-1：覆盖__init__()方法

class ProductsSerializer_Temp(serializers.ModelSerializer):
    images = ImagesSerializer(many=True)

    class Meta:
        fields = (
            'url',
            'id',
            "title",
            "images",
        )
        model = Products


class ProductsSerializer(ProductsSerializer_Temp):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.fields.update(
            {"related_products": ProductsSerializer_Temp()}
        )

另一答案

首先，我认为你应该使用像DynamicFieldsModelSerializer这样的东西来防止递归

class DynamicFieldsModelSerializer(serializers.ModelSerializer):
    """
    A ModelSerializer that takes an additional `fields` argument that
    controls which fields should be displayed.
    """

    def __init__(self, *args, **kwargs):
        # Don't pass the 'fields' arg up to the superclass
        fields = kwargs.pop('fields', None)

        # Instantiate the superclass normally
        super(DynamicFieldsModelSerializer, self).__init__(*args, **kwargs)

        if fields is not None:
            # Drop any fields that are not specified in the `fields` argument.
            allowed = set(fields)
            existing = set(self.fields)
            for field_name in existing - allowed:
                self.fields.pop(field_name)

然后，您可以使用SerializerMethodField并在相关产品中指定您想要的字段（'不要通过related_products以防止递归'）：

class ProductsSerializer(DynamicFieldsModelSerializer):
    images = ImagesSerializer(many=True)
    related_products = serializers.SerializerMethodField()

    def get_related_products(self, obj):
        return ProductsSerializer(obj.related_products, many=True, fields=('url', 'id', "title", "images")).data


    class Meta:
        fields = (
            'url',
            'id',
            "title",
            "related_products",
            "images",
        )
        model = Products

另一答案

这是我遇到过的解决方案。我创建了另一个Serializer

class ProductsSerializerTemp(serializers.ModelSerializer):
    color = ColorSerializer(many=False)

    class Meta:
        fields = (
            "color",
            "url"
        )
        model = Products

而且我把它推荐给我原来的Serializer

class ProductsSerializer(serializers.ModelSerializer):

    images = ImagesSerializer(many=True)
    color = ColorSerializer(many=False)
    related_products = ProductsSerializerTemp(many=True)


    class Meta:
        fields = (
            'url',
            'id',
            "code",
            "sku",
            "title",
            "slug",
            "state",
            "old_price",
            "price",
            "valid",
            "in_stock",
            "category",
            "related_products",
            "color",
            "images",
            "video",
            "description",
            "fabric",
            "model_size_info",
        )
        model = Products

我几乎完成了这项工作，我不确定这是否是最好的解决方案，但效果非常好。