Voucher bulk creation: More efficient implementation and async task

src/pretix/base/services/vouchers.py

@@ -3,22 +3,21 @@ from i18nfield.strings import LazyI18nString
 
 from pretix.base.email import get_email_context
 from pretix.base.i18n import language
-from pretix.base.models import Event, User, Voucher
+from pretix.base.models import Event, LogEntry, User, Voucher
 from pretix.base.services.mail import mail
-from pretix.base.services.tasks import TransactionAwareProfiledEventTask
-from pretix.celery_app import app
 
 
-@app.task(base=TransactionAwareProfiledEventTask, acks_late=True)
-def vouchers_send(event: Event, vouchers: list, subject: str, message: str, recipients: list, user: int) -> None:
+def vouchers_send(event: Event, vouchers: list, subject: str, message: str, recipients: list, user: int,
+                  progress=None) -> None:
     vouchers = list(Voucher.objects.filter(id__in=vouchers).order_by('id'))
     user = User.objects.get(pk=user)
-    for r in recipients:
+    for ir, r in enumerate(recipients):
         voucher_list = []
         for i in range(r['number']):
             voucher_list.append(vouchers.pop())
         with language(event.settings.locale):
-            email_context = get_email_context(event=event, name=r.get('name') or '', voucher_list=[v.code for v in voucher_list])
+            email_context = get_email_context(event=event, name=r.get('name') or '',
+                                              voucher_list=[v.code for v in voucher_list])
             mail(
                 r['email'],
                 subject,
@@ -27,14 +26,14 @@ def vouchers_send(event: Event, vouchers: list, subject: str, message: str, reci
                 event,
                 locale=event.settings.locale,
             )
+            logs = []
             for v in voucher_list:
                 if r.get('tag') and r.get('tag') != v.tag:
                     v.tag = r.get('tag')
                 if v.comment:
                     v.comment += '\n\n'
                 v.comment = gettext('The voucher has been sent to {recipient}.').format(recipient=r['email'])
-                v.save(update_fields=['tag', 'comment'])
-                v.log_action(
+                logs.append(v.log_action(
                     'pretix.voucher.sent',
                     user=user,
                     data={
@@ -42,5 +41,11 @@ def vouchers_send(event: Event, vouchers: list, subject: str, message: str, reci
                         'name': r.get('name'),
                         'subject': subject,
                         'message': message,
-                    }
-                )
+                    },
+                    save=False
+                ))
+            Voucher.objects.bulk_update(voucher_list, fields=['comment', 'tag'], batch_size=500)
+            LogEntry.objects.bulk_create(logs, batch_size=500)
+
+            if progress and ir % 50 == 0:
+                progress(ir / len(recipients))