patched_json_serializer.py

from django.core.serializers.json import Serializer as JsonSerializer

# because of the way serializers are registered, we need to import the Deserializer
from django.core.serializers.json import Deserializer  # noqa


# There's a bug in Django currently, and it doesn't look like it'll be fixed till Django 2.1.
# https://code.djangoproject.com/ticket/24607
# Changes are based on https://github.com/django/django/pull/8370

# To use this, configure SERIALIZATION_MODULES
# SERIALIZATION_MODULES = {
#     'patched_json': 'path.to.patched_json_serializer',
# }
# then run dumpdata like so:
# `python manage.py dumpdata --format=patched_json`


class Serializer(JsonSerializer):
    def get_dump_object(self, obj):
        self._patch_parent_link_natural_key(obj)
        return super().get_dump_object(obj)

    def _patch_parent_link_natural_key(self, obj):
        if not self.use_natural_foreign_keys:
            return

        # note: undocumented API
        # Avoid running that aren't inherited
        if not obj._meta.parents:
            return

        # Use the concrete parent class' _meta instead of the object's _meta
        # This is to avoid local_fields problems for proxy models. Refs #17717.
        concrete_model = obj._meta.concrete_model

        pk = concrete_model._meta.pk
        pk_is_parent = bool(pk and pk.remote_field and pk.remote_field.parent_link)
        if pk_is_parent:
            self.handle_fk_field(obj, pk)