Django REST Framework nested resource key "id" unaccessible

In Django REST Framework AutoField fields (those that are automatically generated) are defaulted to read-only. From the docs:

read_only

Set this to True to ensure that the field is used when serializing a representation, but is not used when creating or updating an instance during deserialization.

Defaults to False

You can see this by inspecting your serializer by printing the representation in your shell:

serializer = ClientfileSerializer()
print repr(serializer)

You can override this by setting read_only=False against the id field in the extra_kwargs:

class ContactSerializer(serializers.ModelSerializer):
  class Meta:
    model = Contact
    fields = (
      'id',
      'first_name',
      'last_name',
    )
    extra_kwargs = {'id': {'read_only': False}}

class ClientfileSerializer(serializers.ModelSerializer):

  owner = ContactSerializer(read_only=False)

  class Meta():
    model = Clientfile
    fields = (
      'id',
      'name',
      'owner',
    )
    extra_kwargs = {'id': {'read_only': False}}

Alright so I found a different approach that works. I added an IntegerField serializer for the owner relation. I also had to set the owner relation to read_only=True.

This is the json I am sending via POST:

{
  name: "Hello!"
  owner_id: 1
}

This is my serializer:

class ClientfileSerializer(serializers.ModelSerializer):

  owner_id = serializers.IntegerField()
  owner = ContactSerializer(read_only=True)

  class Meta():
    model = Clientfile
    fields = (
      'id',
      'owner_id',
      'owner',
    )

It seems less cool than the first way, but it does the job. Plus I don't want to create a new owner, but just select one that is already in the database. So maybe it's more semantic to only have the ID and not the full set of information posted via Json.