Fix #74 -- Warn if quota exceeds after payment

src/pretix/plugins/paypal/payment.py

@@ -8,7 +8,7 @@ from django.contrib import messages
 from django.template.loader import get_template
 from django.utils.translation import ugettext as __, ugettext_lazy as _
 
-from pretix.base.models import Quota
+from pretix.base.models import Quota, RequiredAction
 from pretix.base.payment import BasePaymentProvider
 from pretix.base.services.mail import SendMailException
 from pretix.base.services.orders import mark_order_paid, mark_order_refunded
@@ -203,6 +203,12 @@ class Paypal(BasePaymentProvider):
             mark_order_paid(order, 'paypal', json.dumps(payment.to_dict()))
         except Quota.QuotaExceededException as e:
             messages.error(request, str(e))
+            RequiredAction.objects.create(
+                event=request.event, action_type='pretix.plugins.paypal.overpaid', data=json.dumps({
+                    'order': order.code,
+                    'payment': payment.id
+                })
+            )
         except SendMailException:
             messages.warning(request, _('There was an error sending the confirmation mail.'))
         return None

src/pretix/plugins/paypal/signals.py

@@ -39,10 +39,15 @@ def pretixcontrol_logentry_display(sender, logentry, **kwargs):
 
 @receiver(signal=requiredaction_display, dispatch_uid="paypal_requiredaction_display")
 def pretixcontrol_action_display(sender, action, request, **kwargs):
-    if action.action_type != 'pretix.plugins.paypal.refund':
+    if not action.action_type.startswith('pretix.plugins.paypal'):
         return
 
     data = json.loads(action.data)
-    template = get_template('pretixplugins/paypal/action_refund.html')
+
+    if action.action_type == 'pretix.plugins.paypal.refund':
+        template = get_template('pretixplugins/paypal/action_refund.html')
+    elif action.action_type == 'pretix.plugins.paypal.overpaid':
+        template = get_template('pretixplugins/paypal/action_overpaid.html')
+
     ctx = {'data': data, 'event': sender, 'action': action}
     return template.render(ctx, request)

src/pretix/plugins/paypal/templates/pretixplugins/paypal/action_overpaid.html

@@ -0,0 +1,10 @@
+{% load i18n %}
+
+<p>
+    {% url "control:event.order" organizer=event.organizer.slug event=event.slug code=data.order as ourl %}
+    {% blocktrans trimmed with payment=data.payment order="<a href='"|add:ourl|add:"'>"|add:data.order|add:"</a>"|safe %}
+        The PayPal transaction {{ payment }} has succeeded, but the order {{ order }} is expired and the product
+        was sold out in the meantime. Therefore, the payment could not be acceped. Please contact the user and refund
+        the money via PayPal's interface.
+    {% endblocktrans %}
+</p>

src/pretix/plugins/paypal/views.py

@@ -11,7 +11,7 @@ from django.utils.translation import ugettext_lazy as _
 from django.views.decorators.csrf import csrf_exempt
 from django.views.decorators.http import require_POST
 
-from pretix.base.models import Order, RequiredAction
+from pretix.base.models import Order, Quota, RequiredAction
 from pretix.base.services.orders import mark_order_paid, mark_order_refunded
 from pretix.control.permissions import event_permission_required
 from pretix.multidomain.urlreverse import eventreverse
@@ -103,8 +103,18 @@ def webhook(request, *args, **kwargs):
                 'sale': sale['id']
             })
         )
-    elif order.status == Order.STATUS_PENDING and sale['state'] == 'completed':
-        mark_order_paid(order, user=None)
+    elif order.status in (Order.STATUS_PENDING, Order.STATUS_EXPIRED) and sale['state'] == 'completed':
+        try:
+            mark_order_paid(order, user=None)
+        except Quota.QuotaExceededException:
+            if not RequiredAction.objects.filter(event=request.event, action_type='pretix.plugins.paypal.overpaid',
+                                                 data__icontains=order.code).exists():
+                RequiredAction.objects.create(
+                    event=request.event, action_type='pretix.plugins.paypal.overpaid', data=json.dumps({
+                        'order': order.code,
+                        'payment': sale['parent_payment']
+                    })
+                )
 
     return HttpResponse(status=200)