tomchristie/django-rest-framework — pull request #831 by brianz (2013-05-13 21:44:53+00:00)
Title: Allow nested fields to be missing

Serializer fields which are themselves serializers should not be required.
Specifically, if a nested object is set to "required=False", it should be
possible to serialize the main object and have the sub-object set to None/null.

Before this change, a nested field would throw a KeyError `fields.get_component`.

The new unit tests will fail without the change and all tests pass with this change.