Patch around GeoIP issue

src/pretix/base/forms/questions.py

@@ -45,7 +45,6 @@ import pycountry
 from django import forms
 from django.conf import settings
 from django.contrib import messages
-from django.contrib.gis.geoip2 import GeoIP2
 from django.core.exceptions import ValidationError
 from django.core.files.uploadedfile import SimpleUploadedFile
 from django.core.validators import (
@@ -102,6 +101,7 @@ from pretix.helpers.countries import (
 from pretix.helpers.escapejson import escapejson_attr
 from pretix.helpers.http import get_client_ip
 from pretix.helpers.i18n import get_format_without_seconds
+from pretix.helpers.security import get_geoip
 from pretix.presale.signals import question_form_fields
 
 logger = logging.getLogger(__name__)
@@ -393,7 +393,7 @@ class WrappedPhoneNumberPrefixWidget(PhoneNumberPrefixWidget):
 
 def guess_country_from_request(request, event):
     if settings.HAS_GEOIP:
-        g = GeoIP2()
+        g = get_geoip()
         try:
             res = g.country(get_client_ip(request))
             if res['country_code'] and len(res['country_code']) == 2:

src/pretix/helpers/security.py

@@ -25,7 +25,7 @@ import time
 
 from django.conf import settings
 from django.contrib.auth import login as auth_login
-from django.contrib.gis.geoip2 import GeoIP2
+from django.contrib.gis import geoip2
 from django.core.cache import cache
 from django.utils.timezone import now
 from django.utils.translation import gettext_lazy as _
@@ -63,14 +63,20 @@ def get_user_agent_hash(request):
 _geoip = None
 
 
-def _get_country(request):
+def get_geoip() -> geoip2.GeoIP2:
+    # See https://code.djangoproject.com/ticket/36988#ticket
     global _geoip
 
-    if not _geoip:
-        _geoip = GeoIP2()
+    geoip2.SUPPORTED_DATABASE_TYPES.add("Geoacumen-Country")
 
+    if not _geoip:
+        _geoip = geoip2.GeoIP2()
+    return _geoip
+
+
+def _get_country(request):
     try:
-        res = _geoip.country(get_client_ip(request))
+        res = get_geoip().country(get_client_ip(request))
     except AddressNotFoundError:
         return None
     return res['country_code']