django-simple-history: Admin Integration broken: ContentType matching query does not exist.

Describe the bug Hi, Sorry if this is a user error on my side and I’m wasting your time, but I’m completely stuck at the moment to get the admin panel working. I could easily install and integrate django-simple-history into my app:

• the middleware kicks in OK
• records are being made
• I can access the logs from Django Shell

… but I can’t get the Django Admin/History view to work.

To Reproduce Steps to reproduce the behavior:

1. Go to http://127.0.0.1:8000/myapp/admin/ASD/asd/1/change/
2. Click on 'History in the top-right corner ’
3. See error

Expected behavior See the history of changes as shown in the documentation over here

Screenshots N/A

Environment:

• OS: Windows 10
• Browser (if applicable): Firefox 65.0.2
• Django Simple History Version: 2.7.0
• Django Version: 2.1.5
• Database Version: SQLite (development) | PostgreSQL (production - hadn’t tested yet)

Additional context

django-simple-history works OK:

Python 3.6.7 (v3.6.7:6ec5cf24b7, Oct 20 2018, 13:35:33) [MSC v.1900 64 bit (AMD64)] on win32
Type "help", "copyright", "credits" or "license" for more information.
(InteractiveConsole)
>>> from ASD.models import ASD
>>> e = ASD.objects.get(pk=1)
>>> e.history.all()
<QuerySet [<HistoricalASD: John Appleseed (s12345) | 2019-03-20 as of 2019-03-02 17:15:22.610706+00:00>, <HistoricalASD: The Administrator (admin) | 2019-02-27 as of 2019-03-02 17:14:14.612195+00:00>]>

Traceback thrown on Django Admin/History view

(couple of applications have been removed for brevity and sensitive data have been obfuscated)

Environment:


Request Method: GET
Request URL: http://127.0.0.1:8000/myapp/admin/ASD/asd/1/history/

Django Version: 2.1.5
Python Version: 3.6.7
Installed Applications:
['django.contrib.admin',
 'django.contrib.auth',
 'django.contrib.contenttypes',
 'django.contrib.sessions',
 'django.contrib.messages',
 'django.contrib.staticfiles',
 'rest_framework',
 'simple_history',
 'ASD.apps.AsdConfig',
 'django_extensions']
Installed Middleware:
['django.middleware.security.SecurityMiddleware',
 'django.contrib.sessions.middleware.SessionMiddleware',
 'django.middleware.common.CommonMiddleware',
 'django.middleware.csrf.CsrfViewMiddleware',
 'django.contrib.auth.middleware.AuthenticationMiddleware',
 'django.contrib.messages.middleware.MessageMiddleware',
 'django.middleware.clickjacking.XFrameOptionsMiddleware',
 'simple_history.middleware.HistoryRequestMiddleware']



Traceback:

File "C:\Users\theriverman\.virtualenvs\myapp-back-1wJT2xkN\lib\site-packages\django\contrib\contenttypes\models.py" in get_by_natural_key
  19.             ct = self._cache[self.db][(app_label, model)]

During handling of the above exception (('authsystem', 'user')), another exception occurred:

File "C:\Users\theriverman\.virtualenvs\myapp-back-1wJT2xkN\lib\site-packages\django\core\handlers\exception.py" in inner
  34.             response = get_response(request)

File "C:\Users\theriverman\.virtualenvs\myapp-back-1wJT2xkN\lib\site-packages\django\core\handlers\base.py" in _get_response
  126.                 response = self.process_exception_by_middleware(e, request)

File "C:\Users\theriverman\.virtualenvs\myapp-back-1wJT2xkN\lib\site-packages\django\core\handlers\base.py" in _get_response
  124.                 response = wrapped_callback(request, *callback_args, **callback_kwargs)

File "C:\Users\theriverman\.virtualenvs\myapp-back-1wJT2xkN\lib\site-packages\django\contrib\admin\options.py" in wrapper
  604.                 return self.admin_site.admin_view(view)(*args, **kwargs)

File "C:\Users\theriverman\.virtualenvs\myapp-back-1wJT2xkN\lib\site-packages\django\utils\decorators.py" in _wrapped_view
  142.                     response = view_func(request, *args, **kwargs)

File "C:\Users\theriverman\.virtualenvs\myapp-back-1wJT2xkN\lib\site-packages\django\views\decorators\cache.py" in _wrapped_view_func
  44.         response = view_func(request, *args, **kwargs)

File "C:\Users\theriverman\.virtualenvs\myapp-back-1wJT2xkN\lib\site-packages\django\contrib\admin\sites.py" in inner
  223.             return view(request, *args, **kwargs)

File "C:\Users\theriverman\.virtualenvs\myapp-back-1wJT2xkN\lib\site-packages\simple_history\admin.py" in history_view
  75.         content_type = ContentType.objects.get_by_natural_key(*USER_NATURAL_KEY)

File "C:\Users\theriverman\.virtualenvs\myapp-back-1wJT2xkN\lib\site-packages\django\contrib\contenttypes\models.py" in get_by_natural_key
  21.             ct = self.get(app_label=app_label, model=model)

File "C:\Users\theriverman\.virtualenvs\myapp-back-1wJT2xkN\lib\site-packages\django\db\models\manager.py" in manager_method
  82.                 return getattr(self.get_queryset(), name)(*args, **kwargs)

File "C:\Users\theriverman\.virtualenvs\myapp-back-1wJT2xkN\lib\site-packages\django\db\models\query.py" in get
  399.                 self.model._meta.object_name

Exception Type: DoesNotExist at /myapp/admin/ASD/asd/1/history/
Exception Value: ContentType matching query does not exist.

admin.py

from django.contrib import admin
from simple_history.admin import SimpleHistoryAdmin
from .models import ASD


class AsdHistoryAdmin(SimpleHistoryAdmin):
    list_display = ['id', 'subject', 'date', 'manager', 'is_closed']
    history_list_display = ['id']
    search_fields = ['id', 'subject']

admin.site.register(ASD, PddHistoryAdmin)

models.py

(Removed attribute arguments for brevity)

class ASD(models.Model):
    def get_tasks(self):
        return ASDSubTask.objects.filter(parent_asd=self)

    objects = models.Manager()

    # General Fields
    subject = models.ForeignKey(User, on_delete=models.CASCADE)
    manager = models.ForeignKey(User, on_delete=models.CASCADE)
    date = models.DateField()
    is_closed = models.BooleanField()
    description = models.TextField()
    quick_notes = models.CharField()
    followup_required = models.BooleanField()
    followup_date = models.DateField()
    tasks = property(get_tasks)

    # Misc.
    id = models.AutoField(primary_key=True, verbose_name="ID")
    date_created = models.DateTimeField(auto_now_add=True)
    date_modified = models.DateTimeField(auto_now=True)
    history = HistoricalRecords(verbose_name="ASD History")