将响应序列化为 django rest 框架中的嵌套字段

Question

I had been trying to make a nested json instead of flat json. What I am getting is,

{
    "field1": "value1",
    "field2": "value2" 
}

And I am trying to make as,

{
    "field1": "value1",
    "extra": {
        "x1" : "value2",
        "comment": "my comment"
    }
}

My model is simple,

class MyModel(BaseMeta):
    field1 = models.CharField(db_column='field1', primary_key=True, max_length=11)
    field2 = models.CharField(db_column='field2')

Serializer is

class MyModelSerializer(serializers.Serializer):
    class Meta:
        model = MyModel
        fields = ['field1', 'field2']

The solution is the following,

class MyModelSerializer(serializers.Serializer):
    extra = serializers.SerializerMethodField('get_extra')
    class Meta:
        model = CowMating
        fields = ['field1', 'extra']

    def get_extra(self, obj):
        return {
            'x1': obj.field2,
            'comment': 'my comments'
        }

But I am wondering if its possible to write another serializer like,

class ExtraSerializer(serializers.Serializer):
    x1 = serializers.CharField(source='field2')
    comment = "my comment"

and the serializer would be in the ModelSerializer ,

class MyModelSerializer(serializers.Serializer):
    extra = ExtraSerializer()
    class Meta:
        model = MyModel
        fields = ['field1', 'extra ']

Please give some advice. Thanks in advance.

Answer 1

Yes it's possible that you can refer another serializer in another for nested data and also there's django property that you can use.

your way

class MyModelSerializer(serializers.Serializer):
    extra = ExtraSerializer()
    class Meta:
        model = MyModel
        fields = ['field1', 'extra ']
        depth = 1 .    #<--- Add this

Property

models.py

Suppose you have two models MyModel1 and MyModel2 which has Foreignkey relationship with the MyModel1 .

class MyModel1(BaseMeta):
    field1 = models.CharField(db_column='field1', primary_key=True, max_length=11)
    field2 = models.CharField(db_column='field2')
    @property
    def mymodel2_prop(self, obj):
        from appname.serializer import MyModel2Serialzers    #you have to implement a simple serializer fro MyModel2 which is imported here.
        return MyModel2Serilzers(mymodel2_set.all()).data

So you import the serializer which is optional but a good practice to validate data. using reverse relationship you use set to get the related data in MyModel1 API

class MyModel2(BaseMeta):
        some_field1 = models.ForeignKey(MyModel1, on_delete=models.CASCADE)

serializers.py

class MyModelSerializer(serializers.Serializer):
    class Meta:
        model = MyModel
        fields = ['field1', 'mymodel2_prop '] 

This is to give you an idea, Code is untested