API: Check-in response code for canceled

doc/api/resources/checkinlists.rst

@@ -548,6 +548,8 @@ Order position endpoints
                                        you do not implement question handling in your user interface, you **must**
                                        set this to ``false``. In that case, questions will just be ignored. Defaults
                                        to ``true``.
+   :<json boolean canceled_supported: When this parameter is set to ``true``, the response code ``canceled`` may be
+                                      returned. Otherwise, canceled orders will return ``unpaid``.
    :<json datetime datetime: Specifies the datetime of the check-in. If not supplied, the current time will be used.
    :<json boolean force: Specifies that the check-in should succeed regardless of previous check-ins or required
                          questions that have not been filled. Defaults to ``false``.
@@ -576,6 +578,7 @@ Order position endpoints
         "nonce": "Pvrk50vUzQd0DhdpNRL4I4OcXsvg70uA",
         "datetime": null,
         "questions_supported": true,
+        "canceled_supported": true,
         "answers": {
           "4": "XS"
         }
@@ -659,7 +662,9 @@ Order position endpoints
 
    Possible error reasons:
 
-   * ``unpaid`` - Ticket is not paid for or has been refunded
+   * ``unpaid`` - Ticket is not paid for
+   * ``canceled`` – Ticket is canceled or expired. This reason is only sent when your request sets
+     ``canceled_supported`` to ``true``, otherwise these orders return ``unpaid``.
    * ``already_redeemed`` - Ticket already has been redeemed
    * ``product`` - Tickets with this product may not be scanned at this device
 

src/pretix/api/views/checkin.py

@@ -281,6 +281,7 @@ class CheckinListPositionViewSet(viewsets.ReadOnlyModelViewSet):
                 nonce=nonce,
                 datetime=dt,
                 questions_supported=self.request.data.get('questions_supported', True),
+                canceled_supported=self.request.data.get('canceled_supported', False),
                 user=self.request.user,
                 auth=self.request.auth,
             )

src/pretix/base/services/checkin.py

@@ -60,7 +60,7 @@ def _save_answers(op, answers, given_answers):
 @transaction.atomic
 def perform_checkin(op: OrderPosition, clist: CheckinList, given_answers: dict, force=False,
                     ignore_unpaid=False, nonce=None, datetime=None, questions_supported=True,
-                    user=None, auth=None):
+                    user=None, auth=None, canceled_supported=False):
     """
     Create a checkin for this particular order position and check-in list. Fails with CheckInError if the check in is
     not valid at this time.
@@ -90,10 +90,10 @@ def perform_checkin(op: OrderPosition, clist: CheckinList, given_answers: dict,
         'answers'
     ).get(pk=op.pk)
 
-    if op.canceled:
+    if op.canceled or op.order.status not in (Order.STATUS_PAID, Order.STATUS_PENDING):
         raise CheckInError(
             _('This order position has been canceled.'),
-            'unpaid'
+            'canceled' if canceled_supported else 'unpaid'
         )
 
     answers = {a.question: a for a in op.answers.all()}

src/tests/api/test_checkin.py

@@ -586,6 +586,23 @@ def test_forced_multiple(token_client, organizer, clist, event, order):
 def test_require_paid(token_client, organizer, clist, event, order):
     with scopes_disabled():
         p = order.positions.first()
+
+    order.status = Order.STATUS_CANCELED
+    order.save()
+    resp = token_client.post('/api/v1/organizers/{}/events/{}/checkinlists/{}/positions/{}/redeem/'.format(
+        organizer.slug, event.slug, clist.pk, p.pk
+    ), {}, format='json')
+    assert resp.status_code == 400
+    assert resp.data['status'] == 'error'
+    assert resp.data['reason'] == 'unpaid'
+
+    resp = token_client.post('/api/v1/organizers/{}/events/{}/checkinlists/{}/positions/{}/redeem/'.format(
+        organizer.slug, event.slug, clist.pk, p.pk
+    ), {'canceled_supported': True}, format='json')
+    assert resp.status_code == 400
+    assert resp.data['status'] == 'error'
+    assert resp.data['reason'] == 'canceled'
+
     order.status = Order.STATUS_PENDING
     order.save()
     resp = token_client.post('/api/v1/organizers/{}/events/{}/checkinlists/{}/positions/{}/redeem/'.format(