django rest framework - how do you flatten nested data?

Question

I have a \'through\' model governing a many to many relationship and i want to be able to return the \'through\' model and the target model as flat data, as opposed to havin

Answer 1

I didn't try it with HyperlinkedModelSerializer but with ModelSerializer you can make custom serializer class that supports flatten option.

class CustomModelSerializer(serializers.ModelSerializer):
    def __init__(self, *args, **kwargs):
        self.flatten = kwargs.pop('flatten', False)
        super(CustomModelSerializer, self).__init__(*args, **kwargs)

    def get_fields(self):
        fields = super(CustomModelSerializer, self).get_fields()
        for field_name, field in fields.items():
            if getattr(field, 'flatten', False):
                del fields[field_name]
                for nested_field_name, nested_field in field.fields.iteritems():
                    nested_field.source = (field_name + '.' +
                                           (nested_field.source or nested_field_name))
                    fields[nested_field_name] = nested_field
        return fields

Usage:

class MembershipSerializer(CustomModelSerializer):
    person = PersonSerializer(flatten=True)

    class Meta:
        model = Membership
        fields = ('person', ...)


class PersonSerializer(CustomModelSerializer):

    class Meta:
        model = Person
        fields = (...)