Fix #141 -- Caching improvements for ticket outputs

src/pretix/base/models/orders.py

@@ -8,6 +8,8 @@ import pytz
 from django.conf import settings
 from django.db import models
 from django.db.models import F
+from django.db.models.signals import post_delete
+from django.dispatch import receiver
 from django.utils.crypto import get_random_string
 from django.utils.timezone import make_aware, now
 from django.utils.translation import ugettext_lazy as _
@@ -563,3 +565,9 @@ class CachedTicket(models.Model):
     order_position = models.ForeignKey(OrderPosition, on_delete=models.CASCADE)
     cachedfile = models.ForeignKey(CachedFile, on_delete=models.CASCADE, null=True)
     provider = models.CharField(max_length=255)
+
+
+@receiver(post_delete, sender=CachedTicket)
+def cached_file_delete(sender, instance, **kwargs):
+    if instance.cachedfile:
+        instance.cachedfile.delete()

src/pretix/base/services/orders.py

@@ -21,7 +21,7 @@ from pretix.base.models import (
     CartPosition, Event, Item, ItemVariation, Order, OrderPosition, Quota,
     User, Voucher,
 )
-from pretix.base.models.orders import InvoiceAddress
+from pretix.base.models.orders import CachedTicket, InvoiceAddress
 from pretix.base.payment import BasePaymentProvider
 from pretix.base.services.async import ProfiledTask
 from pretix.base.services.invoices import (
@@ -579,9 +579,13 @@ class OrderChangeManager:
                 self._perform_operations()
             self._recalculate_total_and_payment_fee()
             self._reissue_invoice()
+            self._clear_tickets_cache()
         self._check_paid_to_free()
         self._notify_user()
 
+    def _clear_tickets_cache(self):
+        CachedTicket.objects.filter(order_position__order=self.order).delete()
+
     def _get_payment_provider(self):
         responses = register_payment_providers.send(self.order.event)
         pprov = None

src/pretix/control/views/event.py

@@ -16,7 +16,7 @@ from django.views.generic.detail import SingleObjectMixin
 
 from pretix.base.forms import I18nModelForm
 from pretix.base.models import (
-    Event, EventPermission, Item, ItemVariation, User,
+    CachedTicket, Event, EventPermission, Item, ItemVariation, User,
 )
 from pretix.base.services import tickets
 from pretix.base.services.invoices import build_preview_invoice_pdf
@@ -450,6 +450,9 @@ class TicketSettings(EventPermissionRequiredMixin, FormView):
                             for k in provider.form.changed_data
                         }
                     )
+                    CachedTicket.objects.filter(
+                        order_position__order__event=self.request.event, provider=provider.identifier
+                    ).delete()
             else:
                 success = False
         form = self.get_form(self.get_form_class())

src/pretix/control/views/item.py

@@ -18,8 +18,8 @@ from django.views.generic.edit import DeleteView
 
 from pretix.base.forms import I18nFormSet
 from pretix.base.models import (
-    Item, ItemCategory, ItemVariation, Order, Question, QuestionAnswer,
-    QuestionOption, Quota,
+    CachedTicket, Item, ItemCategory, ItemVariation, Order, Question,
+    QuestionAnswer, QuestionOption, Quota,
 )
 from pretix.control.forms.item import (
     CategoryForm, ItemCreateForm, ItemUpdateForm, ItemVariationForm,
@@ -787,6 +787,7 @@ class ItemUpdateGeneral(ItemDetailMixin, EventPermissionRequiredMixin, UpdateVie
                     for k in form.changed_data
                 }
             )
+            CachedTicket.objects.filter(order_position__item=self.item).delete()
         return super().form_valid(form)
 
 

src/pretix/presale/views/order.py

@@ -401,6 +401,8 @@ class OrderModify(EventViewMixin, OrderDetailMixin, QuestionsViewMixin, Template
             success_message = ('Your invoice address has been updated. Please contact us if you need us '
                                'to regenerate your invoice.')
             messages.success(self.request, _(success_message))
+
+        CachedTicket.objects.filter(order_position__order=self.order).delete()
         return redirect(self.get_order_url())
 
     def get(self, request, *args, **kwargs):