Allow to keep a few per ticket when cancelling an event

src/pretix/base/services/cancelevent.py

@@ -83,8 +83,8 @@ def _send_mail(order: Order, subject: LazyI18nString, message: LazyI18nString, s
 
 @app.task(base=ProfiledEventTask, bind=True, max_retries=5, default_retry_delay=1, throws=(OrderError,))
 def cancel_event(self, event: Event, subevent: int, auto_refund: bool,
-                 keep_fee_fixed: str, keep_fee_percentage: str, keep_fees: list=None, manual_refund: bool=False,
+                 keep_fee_fixed: str, keep_fee_per_ticket: str, keep_fee_percentage: str, keep_fees: list=None,
-                 send: bool=False, send_subject: dict=None, send_message: dict=None,
+                 manual_refund: bool=False, send: bool=False, send_subject: dict=None, send_message: dict=None,
                  send_waitinglist: bool=False, send_waitinglist_subject: dict={}, send_waitinglist_message: dict={},
                  user: int=None, refund_as_giftcard: bool=False, giftcard_expires=None, giftcard_conditions=None,
                  subevents_from: str=None, subevents_to: str=None):
@@ -182,6 +182,10 @@ def cancel_event(self, event: Event, subevent: int, auto_refund: bool,
                 fee += Decimal(keep_fee_percentage) / Decimal('100.00') * (o.total - fee_sum)
             if keep_fee_fixed:
                 fee += Decimal(keep_fee_fixed)
+            if keep_fee_per_ticket:
+                for p in o.positions.all():
+                    if p.addon_to_id is None:
+                        fee += min(p.price, Decimal(keep_fee_per_ticket))
             fee = round_decimal(min(fee, o.payment_refund_sum), event.currency)
 
             _cancel_order(o.pk, user, send_mail=False, cancellation_fee=fee, keep_fees=keep_fee_objects)
@@ -213,6 +217,7 @@ def cancel_event(self, event: Event, subevent: int, auto_refund: bool,
         with transaction.atomic():
             o = event.orders.select_for_update().get(pk=o)
             total = Decimal('0.00')
+            fee = Decimal('0.00')
             positions = []
 
             ocm = OrderChangeManager(o, user=user, notify=False)
@@ -222,7 +227,10 @@ def cancel_event(self, event: Event, subevent: int, auto_refund: bool,
                     ocm.cancel(p)
                     positions.append(p)
 
-            fee = Decimal('0.00')
+                    if keep_fee_per_ticket:
+                        if p.addon_to_id is None:
+                            fee += min(p.price, Decimal(keep_fee_per_ticket))
+
             if keep_fee_fixed:
                 fee += Decimal(keep_fee_fixed)
             if keep_fee_percentage:

src/pretix/control/forms/orders.py

@@ -641,6 +641,12 @@ class EventCancelForm(forms.Form):
         max_digits=10, decimal_places=2,
         required=False
     )
+    keep_fee_per_ticket = forms.DecimalField(
+        label=_("Keep a fixed cancellation fee per ticket"),
+        help_text=_("Free tickets and add-on products are not counted"),
+        max_digits=10, decimal_places=2,
+        required=False
+    )
     keep_fee_percentage = forms.DecimalField(
         label=_("Keep a percentual cancellation fee"),
         max_digits=10, decimal_places=2,

src/pretix/control/templates/pretixcontrol/orders/cancel.html

@@ -41,6 +41,7 @@
             {% bootstrap_field form.gift_card_expires layout="control" %}
             {% bootstrap_field form.gift_card_conditions layout="control" %}
             {% bootstrap_field form.keep_fee_fixed layout="control" %}
+            {% bootstrap_field form.keep_fee_per_ticket layout="control" %}
             {% bootstrap_field form.keep_fee_percentage layout="control" %}
             {% bootstrap_field form.keep_fees layout="control" %}
         </fieldset>

src/pretix/control/views/orders.py

@@ -2082,6 +2082,7 @@ class EventCancel(EventPermissionRequiredMixin, AsyncAction, FormView):
             giftcard_expires=form.cleaned_data.get('gift_card_expires'),
             giftcard_conditions=form.cleaned_data.get('gift_card_conditions'),
             keep_fee_fixed=form.cleaned_data.get('keep_fee_fixed'),
+            keep_fee_per_ticket=form.cleaned_data.get('keep_fee_per_ticket'),
             keep_fee_percentage=form.cleaned_data.get('keep_fee_percentage'),
             keep_fees=form.cleaned_data.get('keep_fees'),
             send=form.cleaned_data.get('send'),

src/tests/base/test_cancelevent.py

@@ -54,7 +54,7 @@ class EventCancelTests(TestCase):
         self.order.save()
         cancel_event(
             self.event.pk, subevent=None,
-            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00",
+            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00", keep_fee_per_ticket="",
             send=True, send_subject="Event canceled", send_message="Event canceled :-( {refund_amount}",
             user=None
         )
@@ -69,7 +69,7 @@ class EventCancelTests(TestCase):
         self.op1.save()
         cancel_event(
             self.event.pk, subevent=None,
-            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00",
+            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00", keep_fee_per_ticket="",
             send=True, send_subject="Event canceled", send_message="Event canceled :-(",
             user=None
         )
@@ -91,7 +91,7 @@ class EventCancelTests(TestCase):
 
         cancel_event(
             self.event.pk, subevent=None,
-            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00",
+            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00", keep_fee_per_ticket="",
             send=True, send_subject="Event canceled", send_message="Event canceled :-(",
             user=None
         )
@@ -119,7 +119,7 @@ class EventCancelTests(TestCase):
 
         cancel_event(
             self.event.pk, subevent=None,
-            auto_refund=False, keep_fee_fixed="0.00", keep_fee_percentage="0.00",
+            auto_refund=False, keep_fee_fixed="0.00", keep_fee_percentage="0.00", keep_fee_per_ticket="",
             send=True, send_subject="Event canceled", send_message="Event canceled :-(",
             user=None
         )
@@ -128,6 +128,84 @@ class EventCancelTests(TestCase):
         assert self.order.status == Order.STATUS_CANCELED
         assert not self.order.refunds.exists()
 
+    @classscope(attr='o')
+    def test_cancel_refund_paid_with_per_ticket_fees(self):
+        gc = self.o.issued_gift_cards.create(currency="EUR")
+        self.order.payments.create(
+            amount=Decimal('46.00'),
+            state=OrderPayment.PAYMENT_STATE_CONFIRMED,
+            provider='giftcard',
+            info='{"gift_card": %d}' % gc.pk
+        )
+        self.order.status = Order.STATUS_PAID
+        self.order.save()
+
+        cancel_event(
+            self.event.pk, subevent=None,
+            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00", keep_fee_per_ticket="2.00",
+            send=False, send_subject="Event canceled", send_message="Event canceled :-(",
+            user=None
+        )
+
+        r = self.order.refunds.get()
+        assert r.state == OrderRefund.REFUND_STATE_DONE
+        assert r.amount == Decimal('42.00')
+        assert r.source == OrderRefund.REFUND_SOURCE_ADMIN
+
+    @classscope(attr='o')
+    def test_cancel_refund_paid_with_per_ticket_fees_ignore_free(self):
+        self.op1.price = Decimal('46.00')
+        self.op1.save()
+        self.op2.price = Decimal('0.00')
+        self.op2.save()
+        gc = self.o.issued_gift_cards.create(currency="EUR")
+        self.order.payments.create(
+            amount=Decimal('46.00'),
+            state=OrderPayment.PAYMENT_STATE_CONFIRMED,
+            provider='giftcard',
+            info='{"gift_card": %d}' % gc.pk
+        )
+        self.order.status = Order.STATUS_PAID
+        self.order.save()
+
+        cancel_event(
+            self.event.pk, subevent=None,
+            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00", keep_fee_per_ticket="2.00",
+            send=False, send_subject="Event canceled", send_message="Event canceled :-(",
+            user=None
+        )
+
+        r = self.order.refunds.get()
+        assert r.state == OrderRefund.REFUND_STATE_DONE
+        assert r.amount == Decimal('44.00')
+        assert r.source == OrderRefund.REFUND_SOURCE_ADMIN
+
+    @classscope(attr='o')
+    def test_cancel_refund_paid_with_per_ticket_fees_ignore_addon(self):
+        self.op2.addon_to = self.op1
+        self.op2.save()
+        gc = self.o.issued_gift_cards.create(currency="EUR")
+        self.order.payments.create(
+            amount=Decimal('46.00'),
+            state=OrderPayment.PAYMENT_STATE_CONFIRMED,
+            provider='giftcard',
+            info='{"gift_card": %d}' % gc.pk
+        )
+        self.order.status = Order.STATUS_PAID
+        self.order.save()
+
+        cancel_event(
+            self.event.pk, subevent=None,
+            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00", keep_fee_per_ticket="2.00",
+            send=False, send_subject="Event canceled", send_message="Event canceled :-(",
+            user=None
+        )
+
+        r = self.order.refunds.get()
+        assert r.state == OrderRefund.REFUND_STATE_DONE
+        assert r.amount == Decimal('44.00')
+        assert r.source == OrderRefund.REFUND_SOURCE_ADMIN
+
     @classscope(attr='o')
     def test_cancel_refund_paid_with_fees(self):
         gc = self.o.issued_gift_cards.create(currency="EUR")
@@ -142,7 +220,7 @@ class EventCancelTests(TestCase):
 
         cancel_event(
             self.event.pk, subevent=None,
-            auto_refund=True, keep_fee_fixed="10.00", keep_fee_percentage="10.00",
+            auto_refund=True, keep_fee_fixed="10.00", keep_fee_percentage="10.00", keep_fee_per_ticket="",
             send=False, send_subject="Event canceled", send_message="Event canceled :-(",
             user=None
         )
@@ -170,7 +248,7 @@ class EventCancelTests(TestCase):
 
         cancel_event(
             self.event.pk, subevent=None,
-            auto_refund=True, keep_fee_fixed="10.00", keep_fee_percentage="10.00",
+            auto_refund=True, keep_fee_fixed="10.00", keep_fee_percentage="10.00", keep_fee_per_ticket="",
             send=False, send_subject="Event canceled", send_message="Event canceled :-(",
             user=None
         )
@@ -201,7 +279,7 @@ class EventCancelTests(TestCase):
 
         cancel_event(
             self.event.pk, subevent=None,
-            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="10.00", keep_fees=[OrderFee.FEE_TYPE_PAYMENT],
+            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="10.00", keep_fees=[OrderFee.FEE_TYPE_PAYMENT], keep_fee_per_ticket="",
             send=False, send_subject="Event canceled", send_message="Event canceled :-(", user=None
         )
         r = self.order.refunds.get()
@@ -237,7 +315,7 @@ class EventCancelTests(TestCase):
 
         cancel_event(
             self.event.pk, subevent=None,
-            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="10.00", keep_fees=[OrderFee.FEE_TYPE_PAYMENT],
+            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="10.00", keep_fees=[OrderFee.FEE_TYPE_PAYMENT], keep_fee_per_ticket="",
             send=False, send_subject="Event canceled", send_message="Event canceled :-(",
             user=None
         )
@@ -266,7 +344,7 @@ class EventCancelTests(TestCase):
 
         cancel_event(
             self.event.pk, subevent=None, manual_refund=True,
-            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00",
+            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00", keep_fee_per_ticket="",
             send=False, send_subject="Event canceled", send_message="Event canceled :-(",
             user=None
         )
@@ -302,7 +380,7 @@ class EventCancelTests(TestCase):
 
         cancel_event(
             self.event.pk, subevent=None, manual_refund=False,
-            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00",
+            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00", keep_fee_per_ticket="",
             send=False, send_subject="Event canceled", send_message="Event canceled :-(",
             user=None
         )
@@ -351,7 +429,7 @@ class SubEventCancelTests(TestCase):
         self.op2.save()
         cancel_event(
             self.event.pk, subevent=self.se1.pk,
-            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00",
+            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00", keep_fee_per_ticket="",
             send=True, send_subject="Event canceled", send_message="Event canceled :-(",
             user=None
         )
@@ -366,7 +444,7 @@ class SubEventCancelTests(TestCase):
         self.op2.save()
         cancel_event(
             self.event.pk, subevent=None, subevents_from=self.se1.date_from - timedelta(days=3), subevents_to=self.se1.date_from - timedelta(days=2),
-            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00",
+            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00", keep_fee_per_ticket="",
             send=True, send_subject="Event canceled", send_message="Event canceled :-(",
             user=None
         )
@@ -374,7 +452,7 @@ class SubEventCancelTests(TestCase):
         assert self.order.status == Order.STATUS_PENDING
         cancel_event(
             self.event.pk, subevent=None, subevents_from=self.se1.date_from - timedelta(days=3), subevents_to=self.se1.date_from + timedelta(days=2),
-            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00",
+            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00", keep_fee_per_ticket="",
             send=True, send_subject="Event canceled", send_message="Event canceled :-(",
             user=None
         )
@@ -387,7 +465,7 @@ class SubEventCancelTests(TestCase):
         self.op2.save()
         cancel_event(
             self.event.pk, subevent=self.se1.pk,
-            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00",
+            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00", keep_fee_per_ticket="",
             send=True, send_subject="Event canceled", send_message="Event canceled :-(",
             user=None
         )
@@ -398,7 +476,7 @@ class SubEventCancelTests(TestCase):
     def test_cancel_all_subevents(self):
         cancel_event(
             self.event.pk, subevent=None,
-            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00",
+            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00", keep_fee_per_ticket="",
             send=True, send_subject="Event canceled", send_message="Event canceled :-(",
             user=None
         )
@@ -418,7 +496,7 @@ class SubEventCancelTests(TestCase):
         self.order.save()
         cancel_event(
             self.event.pk, subevent=self.se1.pk,
-            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00",
+            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00", keep_fee_per_ticket="",
             send=True, send_subject="Event canceled", send_message="Event canceled :-( {refund_amount}",
             user=None
         )
@@ -430,7 +508,7 @@ class SubEventCancelTests(TestCase):
     def test_cancel_mixed_order_range(self):
         cancel_event(
             self.event.pk, subevent=None, subevents_from=self.se1.date_from - timedelta(days=3), subevents_to=self.se1.date_from - timedelta(days=2),
-            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00",
+            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00", keep_fee_per_ticket="",
             send=True, send_subject="Event canceled", send_message="Event canceled :-( {refund_amount}",
             user=None
         )
@@ -439,7 +517,7 @@ class SubEventCancelTests(TestCase):
         assert self.order.positions.count() == 2
         cancel_event(
             self.event.pk, subevent=None, subevents_from=self.se1.date_from - timedelta(days=3), subevents_to=self.se1.date_from + timedelta(days=2),
-            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00",
+            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00", keep_fee_per_ticket="",
             send=True, send_subject="Event canceled", send_message="Event canceled :-( {refund_amount}",
             user=None
         )
@@ -467,7 +545,7 @@ class SubEventCancelTests(TestCase):
 
         cancel_event(
             self.event.pk, subevent=self.se1.pk,
-            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="10.00",
+            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="10.00", keep_fee_per_ticket="",
             send=False, send_subject="Event canceled", send_message="Event canceled :-(",
             user=None
         )
@@ -484,6 +562,31 @@ class SubEventCancelTests(TestCase):
         f = self.order.fees.get(fee_type=OrderFee.FEE_TYPE_CANCELLATION)
         assert f.value == Decimal('1.80')
 
+    @classscope(attr='o')
+    def test_cancel_partially_keep_fees_per_ticket(self):
+        gc = self.o.issued_gift_cards.create(currency="EUR")
+        self.order.payments.create(
+            amount=Decimal('46.00'),
+            state=OrderPayment.PAYMENT_STATE_CONFIRMED,
+            provider='giftcard',
+            info='{"gift_card": %d}' % gc.pk
+        )
+        self.order.status = Order.STATUS_PAID
+        self.order.save()
+
+        cancel_event(
+            self.event.pk, subevent=self.se1.pk,
+            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00", keep_fee_per_ticket="2.00",
+            send=False, send_subject="Event canceled", send_message="Event canceled :-(",
+            user=None
+        )
+        r = self.order.refunds.get()
+        assert r.state == OrderRefund.REFUND_STATE_DONE
+        assert r.amount == Decimal('21.00')
+        assert r.source == OrderRefund.REFUND_SOURCE_ADMIN
+        f = self.order.fees.get(fee_type=OrderFee.FEE_TYPE_CANCELLATION)
+        assert f.value == Decimal('2.00')
+
     @classscope(attr='o')
     def test_cancel_send_mail_waitinglist(self):
         v = Voucher.objects.create(event=self.event, block_quota=True, redeemed=1)
@@ -495,7 +598,7 @@ class SubEventCancelTests(TestCase):
         )
         cancel_event(
             self.event.pk, subevent=None,
-            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00",
+            auto_refund=True, keep_fee_fixed="0.00", keep_fee_percentage="0.00", keep_fee_per_ticket="",
             send=False, send_subject="Event canceled", send_message="Event canceled :-(",
             send_waitinglist=True, send_waitinglist_message="Event canceled", send_waitinglist_subject=":(",
             user=None