From 6ecddfc6c0059a4ffb7372a1753244b7d40104ad Mon Sep 17 00:00:00 2001
From: Raphael Michel <mail@raphaelmichel.de>
Date: Mon, 28 May 2018 11:41:41 +0200
Subject: [PATCH] Automatically re-render PDF for files lost due to bug

---
 src/pretix/base/exporters/invoices.py | 15 +++++++++++----
 src/pretix/control/views/orders.py    | 11 ++++++++---
 src/pretix/presale/views/order.py     |  9 +++++++--
 3 files changed, 26 insertions(+), 9 deletions(-)

diff --git a/src/pretix/base/exporters/invoices.py b/src/pretix/base/exporters/invoices.py
index 8dfd838375..6af2c22f1b 100644
--- a/src/pretix/base/exporters/invoices.py
+++ b/src/pretix/base/exporters/invoices.py
@@ -38,12 +38,19 @@ class InvoiceExporter(BaseExporter):
         with tempfile.TemporaryDirectory() as d:
             with ZipFile(os.path.join(d, 'tmp.zip'), 'w') as zipf:
                 for i in qs:
-                    if not i.file:
+                    try:
+                        if not i.file:
+                            invoice_pdf_task.apply(args=(i.pk,))
+                            i.refresh_from_db()
+                        i.file.open('rb')
+                        zipf.writestr('{}.pdf'.format(i.number), i.file.read())
+                        i.file.close()
+                    except FileNotFoundError:
                         invoice_pdf_task.apply(args=(i.pk,))
                         i.refresh_from_db()
-                    i.file.open('rb')
-                    zipf.writestr('{}.pdf'.format(i.number), i.file.read())
-                    i.file.close()
+                        i.file.open('rb')
+                        zipf.writestr('{}.pdf'.format(i.number), i.file.read())
+                        i.file.close()
 
             with open(os.path.join(d, 'tmp.zip'), 'rb') as zipf:
                 return '{}_invoices.zip'.format(self.event.slug), 'application/zip', zipf.read()
diff --git a/src/pretix/control/views/orders.py b/src/pretix/control/views/orders.py
index 03df6638cf..170d0fd8f1 100644
--- a/src/pretix/control/views/orders.py
+++ b/src/pretix/control/views/orders.py
@@ -31,8 +31,8 @@ from pretix.base.models.orders import OrderFee
 from pretix.base.models.tax import EU_COUNTRIES
 from pretix.base.services.export import export
 from pretix.base.services.invoices import (
-    generate_cancellation, generate_invoice, invoice_pdf, invoice_qualified,
-    regenerate_invoice,
+    generate_cancellation, generate_invoice, invoice_pdf, invoice_pdf_task,
+    invoice_qualified, regenerate_invoice,
 )
 from pretix.base.services.locking import LockTimeoutException
 from pretix.base.services.mail import SendMailException, render_mail
@@ -461,7 +461,12 @@ class InvoiceDownload(EventPermissionRequiredMixin, View):
                                         'now. Please try again in a few seconds.'))
             return redirect(self.get_order_url())
 
-        resp = FileResponse(self.invoice.file.file, content_type='application/pdf')
+        try:
+            resp = FileResponse(self.invoice.file.file, content_type='application/pdf')
+        except FileNotFoundError:
+            invoice_pdf_task.apply(args=(self.invoice.pk,))
+            return self.get(request, *args, **kwargs)
+
         resp['Content-Disposition'] = 'attachment; filename="{}.pdf"'.format(self.invoice.number)
         return resp
 
diff --git a/src/pretix/presale/views/order.py b/src/pretix/presale/views/order.py
index 5cb06ab83a..a7895ae320 100644
--- a/src/pretix/presale/views/order.py
+++ b/src/pretix/presale/views/order.py
@@ -20,7 +20,8 @@ from pretix.base.models.orders import (
 )
 from pretix.base.payment import PaymentException
 from pretix.base.services.invoices import (
-    generate_cancellation, generate_invoice, invoice_pdf, invoice_qualified,
+    generate_cancellation, generate_invoice, invoice_pdf, invoice_pdf_task,
+    invoice_qualified,
 )
 from pretix.base.services.orders import cancel_order
 from pretix.base.services.tickets import (
@@ -673,6 +674,10 @@ class InvoiceDownload(EventViewMixin, OrderDetailMixin, View):
                                         'now. Please try again in a few seconds.'))
             return redirect(self.get_order_url())
 
-        resp = FileResponse(invoice.file.file, content_type='application/pdf')
+        try:
+            resp = FileResponse(invoice.file.file, content_type='application/pdf')
+        except FileNotFoundError:
+            invoice_pdf_task.apply(args=(invoice.pk,))
+            return self.get(request, *args, **kwargs)
         resp['Content-Disposition'] = 'attachment; filename="{}.pdf"'.format(invoice.number)
         return resp