lingo: add callback through payment backend's slug (#49145)

combo/apps/lingo/views.py

@@ -25,6 +25,7 @@ from django.contrib import messages
 from django.contrib.auth.models import User
 from django.core import signing
 from django.core.exceptions import ObjectDoesNotExist, PermissionDenied
+from django.db.models.query import Q
 from django.db.transaction import atomic
 from django.http import (
     Http404,
@@ -611,11 +612,26 @@ class BasketItemPayView(PayMixin, View):
 class PaymentView(View):
     def handle_response(self, request, backend_response, *, callback=True, transaction=None, **kwargs):
         if 'regie_pk' in kwargs:
-            payment_backend = get_object_or_404(Regie, pk=kwargs['regie_pk']).payment_backend
+            try:
+                regie_pk = int(kwargs['regie_pk'])
+            except ValueError:
+                regie_pk = None
+            payment_backend = PaymentBackend.objects.filter(regie__pk=regie_pk).first()
         elif 'payment_backend_pk' in kwargs:
-            payment_backend = get_object_or_404(PaymentBackend, pk=kwargs['payment_backend_pk'])
+            payment_backend_slug = kwargs['payment_backend_pk']
+            try:
+                payment_backend_pk = int(kwargs['payment_backend_pk'])
+            except ValueError:
+                payment_backend_pk = None
+            payment_backend = PaymentBackend.objects.filter(
+                Q(pk=payment_backend_pk) | Q(slug=payment_backend_slug)
+            ).first()
         else:
-            return HttpResponseBadRequest("A payment backend or regie primary key must be specified")
+            payment_backend = None
+
+        if not payment_backend:
+            logger.warning('lingo: payment backend not found on callback kwargs=%r', kwargs)
+            raise Http404("A payment backend or regie primary key or slug must be specified")
 
         payment = payment_backend.make_eopayment(request=request)
         logger.info(u'received payment response: %r', backend_response)