Django Admin - 'bool' object is not callable - django

Question

When I try and delete records within Django Admin, for some records, I am getting
'bool' object is not callable
I cannot work out where the error is based on this Traceback.
Traceback:
File "/home/henry/Documents/Sites/Development/django-authenticjobs/env/lib/python3.6/site-packages/django/core/handlers/exception.py" in inner
35. response = get_response(request)
File "/home/henry/Documents/Sites/Development/django-authenticjobs/env/lib/python3.6/site-packages/django/core/handlers/base.py" in _get_response
128. response = self.process_exception_by_middleware(e, request)
File "/home/henry/Documents/Sites/Development/django-authenticjobs/env/lib/python3.6/site-packages/django/core/handlers/base.py" in _get_response
126. response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "/home/henry/Documents/Sites/Development/django-authenticjobs/env/lib/python3.6/site-packages/django/contrib/admin/options.py" in wrapper
575. return self.admin_site.admin_view(view)(*args, **kwargs)
File "/home/henry/Documents/Sites/Development/django-authenticjobs/env/lib/python3.6/site-packages/django/utils/decorators.py" in _wrapped_view
142. response = view_func(request, *args, **kwargs)
File "/home/henry/Documents/Sites/Development/django-authenticjobs/env/lib/python3.6/site-packages/django/views/decorators/cache.py" in _wrapped_view_func
44. response = view_func(request, *args, **kwargs)
File "/home/henry/Documents/Sites/Development/django-authenticjobs/env/lib/python3.6/site-packages/django/contrib/admin/sites.py" in inner
223. return view(request, *args, **kwargs)
File "/home/henry/Documents/Sites/Development/django-authenticjobs/env/lib/python3.6/site-packages/django/utils/decorators.py" in _wrapper
62. return bound_func(*args, **kwargs)
File "/home/henry/Documents/Sites/Development/django-authenticjobs/env/lib/python3.6/site-packages/django/utils/decorators.py" in _wrapped_view
142. response = view_func(request, *args, **kwargs)
File "/home/henry/Documents/Sites/Development/django-authenticjobs/env/lib/python3.6/site-packages/django/utils/decorators.py" in bound_func
58. return func.__get__(self, type(self))(*args2, **kwargs2)
File "/home/henry/Documents/Sites/Development/django-authenticjobs/env/lib/python3.6/site-packages/django/contrib/admin/options.py" in delete_view
1736. return self._delete_view(request, object_id, extra_context)
File "/home/henry/Documents/Sites/Development/django-authenticjobs/env/lib/python3.6/site-packages/django/contrib/admin/options.py" in _delete_view
1760. [obj], opts, request.user, self.admin_site, using)
File "/home/henry/Documents/Sites/Development/django-authenticjobs/env/lib/python3.6/site-packages/django/contrib/admin/utils.py" in get_deleted_objects
131. collector.collect(objs)
File "/home/henry/Documents/Sites/Development/django-authenticjobs/env/lib/python3.6/site-packages/django/contrib/admin/utils.py" in collect
195. return super().collect(objs, source_attr=source_attr, **kwargs)
File "/home/henry/Documents/Sites/Development/django-authenticjobs/env/lib/python3.6/site-packages/django/db/models/deletion.py" in collect
222. field.remote_field.on_delete(self, field, sub_objs, self.using)
Exception Type: TypeError at /admin/jobboard/job/155/delete/
Exception Value: 'bool' object is not callable
Can anyone suggest where to look? Thank you

Answer 1

You have set an on_delete of a ForeignKey, or OneToOneField to a boolean (True or False). So something like:
class SomeModel(models.Model):
some_fk = models.ForeignKey(OtherModel, on_delete=False)
You can not set this to a boolean. You can set this to the values listed in the documentation: CASCADE, PROTECT, SET_NULL, SET_DEFAULT, SET(..), or DO_NOTHING.
You could, strictly speaking, implement your own strategy as well, since the ones listed above are in fact just functions. For example the CASCADE is implemented like [GitHub]:
def CASCADE(collector, field, sub_objs, using):
collector.collect(sub_objs, source=field.remote_field.model,
source_attr=field.name, nullable=field.null)
if field.null and not connections[using].features.can_defer_constraint_checks:
collector.add_field_update(field, None, sub_objs)
although likely you do not need to implement your own, and pick one of the ones listed in the documentation. For example:
class SomeModel(models.Model):
some_fk = models.ForeignKey(OtherModel, on_delete=models.CASCADE)