Django EmbeddedModelField saying “This field may not be blank” when doing PUT request despite field having “blank=True”

I'm creating a Django application with django-rest-framework and using djongo to connect to MongoDB. I have nested models as such:

class Group(models.Model):
    users = models.ArrayModelField(
        model_container=User
    )
class User(models.Model):

number = models.IntegerField(

default=None,

null=True

)
song = models.EmbeddedModelField(
    model_container=Song,
    null=True,
    blank=True
)

class Meta:
    abstract = True

class Song(models.Model):

mp3_file = models.URLField(

default=None,

blank=True,

null=True

)
comments = models.CharField(
    max_length=250,
    default='',
    blank=True
)

class Meta:
    abstract = True

When a Group is created, the Users and the Songs are created without any problems. For example, when created, the Group may look like:

{

“name”: “Sample”,

"users: [

{

“number”: null,

“song”: {

“mp3_file”: null,

“comments”: “”

}

}

]

}

This all works fine. However, if I try to do a PUT request and don’t change the value of “number”, “mp3_file”, or “comments”, I will get the following error message:

“user”: [

{

“number”: [

“This field may not be null.”

],

“song”: {

“mp3_file”: [

“This field may not be null.”

],

“comments”: [

“This field may not be blank.”

]

}

}

]

Any thoughts on how to fix this error? I am just using a generic RetrieveUpdateDestroyAPIView as the view for this endpoint.

edit: I have also tried recreating all migrations as well as dropping the table and recreating it, and neither of those approaches helped.

edit: Here is the view:

class GroupDetail(generics.RetrieveUpdateDestroyAPIView):

serializer_class = GroupSerializer

queryset = Group.objects.all()

lookup_field = ‘group_name’

lookup_url_kwarg = ‘group_name’

And the serializers:

class GroupSerializer(serializers.HyperlinkedModelSerializer):

users = UserSerializer(many=True)

def update(self, instance, validated_data):
    if validated_data.get('group_name', None) is not None:
        instance.__setattr__('group_name', validated_data.get('group_name'))

    instance.save()

    return instance

class Meta:
    model = Group
    fields = (
        'group_name',
        'users'
    )

class UserSerializer(serializers.Serializer):

number = serializers.IntegerField()

song = SongSerializer()
class SongSerializer(serializers.Serializer):

mp3_file = serializers.URLField()

comments = serializers.CharField(

max_length=250

)

But part of the issue is that the serializers are never even being reached since the data is validating incorrectly.

#django #mongodb