Let plugins allow/prevent the download of individual tickets in an order (#3836)

(extends the functionality of the allow_ticket_download signal)

src/pretix/base/models/orders.py

@@ -44,7 +44,7 @@ from datetime import datetime, time, timedelta
 from decimal import Decimal
 from functools import reduce
 from time import sleep
-from typing import Any, Dict, List, Union
+from typing import Any, Dict, Iterable, List, Union
 from zoneinfo import ZoneInfo
 
 import dateutil
@@ -79,7 +79,7 @@ from pretix.base.i18n import language
 from pretix.base.models import Customer, User
 from pretix.base.reldate import RelativeDateWrapper
 from pretix.base.settings import PERSON_NAME_SCHEMES
-from pretix.base.signals import order_gracefully_delete
+from pretix.base.signals import allow_ticket_download, order_gracefully_delete
 
 from ...helpers import OF_SELF
 from ...helpers.countries import CachedCountries, FastCountryField
@@ -1137,12 +1137,19 @@ class Order(LockModel, LoggedModel):
                 attach_tickets=True,
             )
 
+    @property
+    def positions_with_tickets_ignoring_plugins(self):
+        return (op for op in self.positions.select_related('item') if op.generate_ticket)
+
     @property
     def positions_with_tickets(self):
-        for op in self.positions.select_related('item'):
-            if not op.generate_ticket:
-                continue
-            yield op
+        signal_response = allow_ticket_download.send(self.event, order=self)
+        if all([r is True for rr, r in signal_response]):
+            return self.positions_with_tickets_ignoring_plugins
+        elif any([r is False for rr, r in signal_response]):
+            return []
+        else:
+            return set.intersection(set(self.positions_with_tickets_ignoring_plugins), *[set(r) for rr, r in signal_response if isinstance(r, Iterable)])
 
     def create_transactions(self, is_new=False, positions=None, fees=None, dt_now=None, migrated=False,
                             _backfill_before_cancellation=False, save=True):

src/pretix/base/services/orders.py

@@ -98,10 +98,9 @@ from pretix.base.services.pricing import (
 from pretix.base.services.quotas import QuotaAvailability
 from pretix.base.services.tasks import ProfiledEventTask, ProfiledTask
 from pretix.base.signals import (
-    allow_ticket_download, order_approved, order_canceled, order_changed,
-    order_denied, order_expired, order_fee_calculation, order_paid,
-    order_placed, order_split, order_valid_if_pending, periodic_task,
-    validate_order,
+    order_approved, order_canceled, order_changed, order_denied, order_expired,
+    order_fee_calculation, order_paid, order_placed, order_split,
+    order_valid_if_pending, periodic_task, validate_order,
 )
 from pretix.celery_app import app
 from pretix.helpers import OF_SELF
@@ -1408,23 +1407,16 @@ def send_download_reminders(sender, **kwargs):
             if o.download_reminder_sent:
                 # Race condition
                 continue
-            if not all([r for rr, r in allow_ticket_download.send(event, order=o)]):
+            positions = o.positions_with_tickets
+            if not list(positions):
                 continue
 
             if not o.ticket_download_available:
                 continue
-            positions = o.positions.select_related('item')
 
             if o.status != Order.STATUS_PAID:
                 if o.status != Order.STATUS_PENDING or o.require_approval or (not o.valid_if_pending and not o.event.settings.ticket_download_pending):
                     continue
-            send = False
-            for p in positions:
-                if p.generate_ticket:
-                    send = True
-                    break
-            if not send:
-                continue
 
             with language(o.locale, o.event.settings.region):
                 o.download_reminder_sent = True
@@ -1442,10 +1434,7 @@ def send_download_reminders(sender, **kwargs):
                     logger.exception('Reminder email could not be sent')
 
                 if event.settings.mail_send_download_reminder_attendee:
-                    for p in o.positions.all():
-                        if not p.generate_ticket:
-                            continue
-
+                    for p in o.positions_with_tickets:
                         if p.subevent_id:
                             reminder_date = (p.subevent.date_from - timedelta(days=days)).replace(
                                 hour=0, minute=0, second=0, microsecond=0

src/pretix/base/services/tickets.py

@@ -34,7 +34,7 @@ from pretix.base.models import (
 )
 from pretix.base.services.tasks import EventTask, ProfiledTask
 from pretix.base.settings import PERSON_NAME_SCHEMES
-from pretix.base.signals import allow_ticket_download, register_ticket_outputs
+from pretix.base.signals import register_ticket_outputs
 from pretix.celery_app import app
 from pretix.helpers.database import rolledback_transaction
 
@@ -124,8 +124,8 @@ def preview(event: int, provider: str):
 
 
 def get_tickets_for_order(order, base_position=None):
-    can_download = all([r for rr, r in allow_ticket_download.send(order.event, order=order)])
-    if not can_download:
+    positions = list(order.positions_with_tickets)
+    if not positions:
         return []
     if not order.ticket_download_available:
         return []
@@ -135,10 +135,8 @@ def get_tickets_for_order(order, base_position=None):
         for receiver, response
         in register_ticket_outputs.send(order.event)
     ]
-
     tickets = []
 
-    positions = list(order.positions_with_tickets)
     if base_position:
         # Only the given position and its children
         positions = [
@@ -202,7 +200,6 @@ def get_tickets_for_order(order, base_position=None):
                     ))
                 except:
                     logger.exception('Failed to generate ticket.')
-
     return tickets
 
 

src/pretix/base/signals.py

@@ -646,7 +646,7 @@ allow_ticket_download = EventPluginSignal()
 Arguments: ``order``
 
 This signal is sent out to check if tickets for an order can be downloaded. If any receiver returns false,
-a download will not be offered.
+a download will not be offered. If a receiver returns a list of OrderPositions, only those will be downloadable.
 
 As with all event-plugin signals, the ``sender`` keyword argument will contain the event.
 """

src/pretix/base/ticketoutput.py

@@ -96,6 +96,9 @@ class BaseTicketOutput:
         """
         raise NotImplementedError()
 
+    def get_tickets_to_print(self, order):
+        return order.positions_with_tickets
+
     def generate_order(self, order: Order) -> Tuple[str, str, str]:
         """
         This method is the same as order() but should not generate one file per order position
@@ -116,7 +119,7 @@ class BaseTicketOutput:
         """
         with tempfile.TemporaryDirectory() as d:
             with ZipFile(os.path.join(d, 'tmp.zip'), 'w') as zipf:
-                for pos in order.positions_with_tickets:
+                for pos in self.get_tickets_to_print(order):
                     fname, __, content = self.generate(pos)
                     zipf.writestr('{}-{}{}'.format(
                         order.code, pos.positionid, os.path.splitext(fname)[1]