Change a field in a Django REST Framework ModelSerializer based on the request type?

Question

Consider this case where I have a Book and Author model.

serializers.py

class AuthorSerializer(serializers.ModelSerializer):

         


        

Answer 1

The way I ended up dealing with this problem was having another serializer for when it's a related field.

class HumanSerializer(PersonSerializer):

    class Meta:
        model = Human
        fields = PersonSerializer.Meta.fields + (
            'firstname',
            'middlename',
            'lastname',
            'sex',
            'date_of_birth',
            'balance'
        )
        read_only_fields = ('name',)


class HumanRelatedSerializer(HumanSerializer):
    def to_internal_value(self, data):
        return self.Meta.model.objects.get(id=data['id'])


class PhoneNumberSerializer(serializers.ModelSerializer):
    contact = HumanRelatedSerializer()

    class Meta:
        model = PhoneNumber
        fields = (
            'id',
            'contact',
            'phone',
            'extension'
        )

You could do something like this, but for the RelatedSerializer do:

 def to_internal_value(self, data):
     return self.Meta.model.objects.get(id=data)

Thus, when serializing, you serialize the related object, and when de-serializing, you only need the id to get the related object.