Prototype for PDF generation

src/pretix/presale/urls.py

@@ -22,6 +22,8 @@ urlpatterns = [
             name='event.order.cancel'),
         url(r'^order/(?P<order>[^/]+)/modify$', pretix.presale.views.order.OrderModify.as_view(),
             name='event.order.modify'),
+        url(r'^order/(?P<order>[^/]+)/download$', pretix.presale.views.order.OrderDownload.as_view(),
+            name='event.order.download'),
         url(r'^login$', pretix.presale.views.event.EventLogin.as_view(), name='event.checkout.login'),
         url(r'^logout$', pretix.presale.views.event.EventLogout.as_view(), name='event.logout'),
         url(r'^orders$', pretix.presale.views.event.EventOrders.as_view(), name='event.orders'),

src/pretix/presale/views/order.py

@@ -1,17 +1,22 @@
-from datetime import datetime
-from itertools import groupby
+from io import StringIO, BytesIO
 from django.contrib import messages
 from django.core.urlresolvers import reverse
 from django.shortcuts import redirect
-from django.utils.timezone import now
 from django.utils.translation import ugettext_lazy as _
 from django.utils.functional import cached_property
-from django.views.generic import TemplateView
-from django.http import HttpResponseNotFound, HttpResponseForbidden
+from django.views.generic import TemplateView, View
+from django.http import HttpResponseNotFound, HttpResponseForbidden, HttpResponse
 from pretix.base.models import Order, OrderPosition
 from pretix.base.signals import register_payment_providers
 from pretix.presale.views import EventViewMixin, EventLoginRequiredMixin, CartDisplayMixin
 from pretix.presale.views.checkout import QuestionsViewMixin
+from reportlab.graphics.shapes import Drawing
+from reportlab.pdfgen import canvas
+from reportlab.lib import pagesizes, units
+from reportlab.graphics.barcode.qr import QrCodeWidget
+from reportlab.graphics import renderPDF
+from PyPDF2 import PdfFileWriter, PdfFileReader
+from django.contrib.staticfiles import finders
 
 
 class OrderDetailMixin:
@@ -140,3 +145,66 @@ class OrderCancel(EventViewMixin, EventLoginRequiredMixin, OrderDetailMixin,
         ctx = super().get_context_data(**kwargs)
         ctx['order'] = self.order
         return ctx
+
+
+class OrderDownload(EventViewMixin, EventLoginRequiredMixin, OrderDetailMixin,
+                    View):
+
+    def get(self, request, *args, **kwargs):
+        if self.order.status != Order.STATUS_PAID:
+            return HttpResponseForbidden(_('Order is not paid'))
+        response = HttpResponse(content_type='application/pdf')
+        response['Content-Disposition'] = 'inline; filename="order%s%s.pdf"' % (request.event.slug, self.order.code)
+
+        pagesize = request.event.settings.get('ticketpdf_pagesize', default='A4')
+        if hasattr(pagesizes, pagesize):
+            pagesize = getattr(pagesizes, pagesize)
+        else:
+            pagesize = pagesizes.A4
+        defaultfname = finders.find('pretixpresale/pdf/ticket_default_a4.pdf')
+        fname = request.event.settings.get('ticketpdf_background', default=defaultfname)
+        # TODO: Handle file objects
+
+        buffer = BytesIO()
+        p = canvas.Canvas(buffer, pagesize=pagesize)
+
+        for op in self.order.positions.all().select_related('item', 'variation'):
+            p.setFont("Helvetica", 22)
+            p.drawString(15 * units.mm, 235 * units.mm, request.event.name)
+
+            p.setFont("Helvetica", 17)
+            item = op.item.name
+            if op.variation:
+                item += " – " + str(op.variation)
+            p.drawString(15 * units.mm, 220 * units.mm, item)
+
+            p.setFont("Helvetica", 17)
+            p.drawString(15 * units.mm, 210 * units.mm, "%s %s" % (str(op.price), request.event.currency))
+
+            reqs = 80 * units.mm
+            qrw = QrCodeWidget(op.identity, barLevel='H')
+            b = qrw.getBounds()
+            w = b[2] - b[0]
+            h = b[3] - b[1]
+            d = Drawing(reqs, reqs, transform=[reqs / w, 0, 0, reqs / h, 0, 0])
+            d.add(qrw)
+            renderPDF.draw(d, p, 10 * units.mm, 130 * units.mm)
+
+            p.setFont("Helvetica", 11)
+            p.drawString(15 * units.mm, 130 * units.mm, op.identity)
+
+            p.showPage()
+
+        p.save()
+
+        buffer.seek(0)
+        new_pdf = PdfFileReader(buffer)
+        output = PdfFileWriter()
+        for page in new_pdf.pages:
+            bg_pdf = PdfFileReader(open(fname, "rb"))
+            bg_page = bg_pdf.getPage(0)
+            bg_page.mergePage(page)
+            output.addPage(bg_page)
+
+        output.write(response)
+        return response