使用 ForeignKey 从 Django 嵌套查询集中检索嵌套字典？

Question

我有一个models.py 有：

class Other(models.Model):
    name = models.CharField(max_length=200)

class ModelA(models.Model):
    name = models.CharField(max_length=200)
    other = models.ForeignKey(Other, on_delete=models.PROTECT)

在我的其余 API 中，我想以 JsonResponse 的形式检索一个像这样的 json：

{
    "modelA": {
        "id": "modelA id automatically assigned by django model",
        "name": "my modelA name",
        "other": {
            "id": "other thing id also automatically assigned by django model",
            "name": "other thing name"
        }
    }
}

最“pythonic”的方法是什么？

Answer 1

你要找的是nested serialization。

在您的serializers.py 中，您应该使用Other 模型的序列化程序在内部为您的ModelA 使用序列化程序。

在serializers.py:

from rest_framework import serializers

from .models import Other, ModelA


class OtherSerializer(serializers.ModelSerializer):
    class Meta:
        model = Other
        fields = ('id', 'name')


class ModelASerializer(serializers.ModelSerializer):
    other = OtherSerializer(read_only=True)
    # The magic happens here.
    # You use your already created OtherSerializer inside the one for ModelA
    # And that will perform nested serialization
    # Which will produce the result that you want

    class Meta:
        model = ModelA
        fields = ('id', 'name', 'other')
        # _________________________^

现在你得到如下结果：

{
    "id": 1,
    "name": "my modelA name",
    "other": {
        "id": 1,
        "name": "other thing name"
    }
 }