Add error handling for PDF generation view

aleksis/apps/kort/views.py

@@ -105,13 +105,20 @@ class CardPrintView(PermissionRequiredMixin, RevisionMixin, SingleObjectMixin, V
         printer = self.request.GET.get("printer")
         printer = get_object_or_404(CardPrinter, pk=printer)
 
-        self.object.print_card(printer)
-        messages.success(
-            request,
-            _(
-                "The print job for the card {} on the printer {} has been created successfully."
-            ).format(self.object.person, printer.name),
-        )
+        try:
+            job = self.object.print_card(printer)
+            messages.success(
+                request,
+                _(
+                    "The print job #{} for the card {} on "
+                    "the printer {} has been created successfully."
+                ).format(job.pk, self.object.person, printer.name),
+            )
+        except ValueError as e:
+            messages.error(
+                request,
+                _("The print job couldn't be started because of the following error: {}").format(e),
+            )
 
         return redirect(self.success_url)