Add customized links to page footer (#2685)

Co-authored-by: Richard Schreiber <wiffbi@gmail.com>

src/pretix/base/models/organizer.py

@@ -46,6 +46,7 @@ from django.utils.crypto import get_random_string
 from django.utils.functional import cached_property
 from django.utils.timezone import get_current_timezone, make_aware, now
 from django.utils.translation import gettext_lazy as _
+from i18nfield.fields import I18nCharField
 
 from pretix.base.models.base import LoggedModel
 from pretix.base.validators import OrganizerSlugBanlistValidator
@@ -464,3 +465,25 @@ class TeamAPIToken(models.Model):
             return self.get_events_with_any_permission()
         else:
             return self.team.organizer.events.none()
+
+
+class OrganizerFooterLink(models.Model):
+    """
+    A footer link assigned to an organizer.
+    """
+    organizer = models.ForeignKey('Organizer', on_delete=models.CASCADE, related_name='footer_links')
+    label = I18nCharField(
+        max_length=200,
+        verbose_name=_("Link text"),
+    )
+    url = models.URLField(
+        verbose_name=_("Link URL"),
+    )
+
+    def delete(self, *args, **kwargs):
+        super().delete(*args, **kwargs)
+        self.organizer.cache.clear()
+
+    def save(self, *args, **kwargs):
+        super().save(*args, **kwargs)
+        self.organizer.cache.clear()