FieldError trying to delete Django instances with generic foreign key

While fixing some errors, I made two test instances. Now that I finished that, I wanted to delete those two tests:

nj.delete()

raise FieldError("Cannot resolve keyword '%s' into field. "
django.core.exceptions.FieldError: Cannot resolve keyword 'content_type' into field. Choices are: awards, career_highlights, content_object_org, content_object_pc, content_type_org, content_type_org_id, content_type_pc, content_type_pc_id, date_updated, daterange, end_date, honors, object_id_org, object_id_pc, org_history_updated, publications, role, significant_event, start_date, title, uniqid, updated_Vitae_bio_and_org_history

This error is not on the model I was deleting from, but an intermediate model which also has a generic foreign key. Django can’t find the field ‘content_type’ because there is no such field, so I don’t know why it is looking for it. There is a content_type_org and a content_type_pc. From the context I assume Django wants the content_type_org. But how do I tell Django to look for that instead? I also tried going to the superclass and deleting the same object from there,

jn.delete()

but got the same error.

Solution

As mentioned in the comments, it's difficult to assist without seeing your models. Nevertheless it appears you have renamed the content_type field that is used in the GenericForeignKey. You'll need to specify the renamed field on the related model using a GenericRelation like so:

class TaggedItem(models.Model):
    
    content_type_fk = models.ForeignKey(ContentType, on_delete=models.CASCADE)
    object_primary_key = models.PositiveIntegerField()
    content_object = GenericForeignKey('content_type_fk', 'object_primary_key')


class Blog(models.Model):
    tags = GenericRelation(
        TaggedItem,
        content_type_field='content_type_fk',
        object_id_field='object_primary_key',
    )

See the docs for details.