How to serialize a Hstore field in drf

Question

I have an HStoreField in my model. Example:

attributes = HStoreField(default=dict, blank=True)

My view and serializer:

class CarSerializer(serializers.ModelSerializer):

    class Meta:
        model = Car
        fields = "__all__"

class CarViewSet(viewsets.ModelViewSet):
    queryset = Car.objects.all()
    serializer_class = CarSerializer
    model = Car

Ok. When I try some tests, like this:

@pytest.fixture
def create_car(client):
    response = client.post(
        '/myapi/v1/car/',
        data={
            'name': "Ford Mustang",
            'price': 2000,
            'attributes': {"key": "value"},
        },
        format='json',
    )
    return response

@pytest.mark.django_db
def test_car_view(client, create_car):
    response = create_car
    response_get = client.get(f'/myapi/v1/car/{response.data["id"]}/')
    assert response_get.status_code == 200

I receive this error:

self = HStoreField(required=False), value = '"key"=>NULL'

    def to_representation(self, value):
        """
        List of object instances -> List of dicts of primitive datatypes.
        """
        return {
            six.text_type(key): self.child.to_representation(val) if val is not None else None
>           for key, val in value.items()
        }
E       AttributeError: 'str' object has no attribute 'items'

Looking for information about this problem I found references to use DictField for working with HStoreField. But I did not find examples. Does someone have an idea or examples?

Answer 1

I got it!

I needed to set attributes as a JSONField.

My solution:

class CarSerializer(serializers.ModelSerializer):

    attributes = serializers.JSONField()

    class Meta:
        model = Car
        fields = "__all__"