Fix checkin QR code URL

Use site URL in generated emails instead of hard coded domain.

vendor/regidesk/regidesk/views.py

@@ -10,6 +10,7 @@ from django.contrib import messages
 from django.contrib.auth.decorators import permission_required, user_passes_test, login_required
 from django.contrib.auth.mixins import PermissionRequiredMixin
 from django.contrib.auth.models import User, Group
+from django.contrib.sites.models import Site
 from django.db import transaction
 from django.db.models import F, Q
 from django.db.models import Count, Max, Sum
@@ -126,6 +127,22 @@ def checkin_png(request, checkin_code):
 
     return response
 
+
+def checkin_qrcode_url(code):
+    """ Generate the QR code URL for the current site.
+    eg. https://rego.linux.conf.au/checkin/<code>.png
+    """
+
+    # Cannot use build_absolute_uri as external URL is not known in docker
+    # qrcode_url = request.build_absolute_uri(
+    #     reverse("regidesk:checkin_png", args=[code]))
+
+    current_site = Site.objects.get_current()
+    qrcode_url = "https://{}{}".format(current_site,
+        reverse("regidesk:checkin_png", args=[code]))
+    return qrcode_url
+
+
 @permission_required("regidesk.send_boarding_pass")
 def boarding_prepare(request):
 
@@ -161,9 +178,7 @@ def boarding_prepare(request):
             "boardingpass": sample_checkin.boardingpass,
             "code": sample_checkin.code,
             "qrcode": '<img src="data:image/png;base64,' + sample_checkin.qrcode + '"/>',
-            # "qrcode_url": request.build_absolute_uri(
-            #     reverse("regidesk:checkin_png", args=[sample_checkin.code])),
-           "qrcode_url": "https://rego.linux.conf.au/checkin/" + sample_checkin.code + ".png"
+            "qrcode_url": checkin_qrcode_url(sample_checkin.code),
         }
         ctx = Context(sample_ctx)
         ctx["invoices"] = invoices(ctx)
@@ -205,9 +220,7 @@ def prepare_boarding_pass(user, template, attendee=None):
         "checkin": user.checkin,
         "code": user.checkin.code,
         "qrcode": user.checkin.qrcode,
-        # "qrcode_url": request.build_absolute_uri(
-        #     reverse("regidesk:checkin_png", args=[user.checkin.code])),
-        "qrcode_url": "https://rego.linux.conf.au/checkin/" + user.checkin.code + ".png"
+        "qrcode_url": checkin_qrcode_url(user.checkin.code),
     }
     ctx = Context(ctx)
     ctx["invoices"] = invoices(ctx)