Fix bug that results in AttributeError - 'OccurrencePreview' object h…

…as no attribute 'object'

schedule/views.py

@@ -34,7 +34,7 @@
 
 from schedule.forms import EventForm, OccurrenceForm
 from schedule.models import Calendar, Event, Occurrence
-from schedule.periods import weekday_names
+from schedule.periods import weekday_names, Period
 from schedule.settings import (
     CHECK_EVENT_PERM_FUNC,
     CHECK_OCCURRENCE_PERM_FUNC,
@@ -157,6 +157,35 @@ class OccurrenceView(OccurrenceMixin, DetailView):
 class OccurrencePreview(OccurrenceMixin, ModelFormMixin, ProcessFormView):
     template_name = "schedule/occurrence.html"
 
+    @property
+    def date_from_url(self):
+        return datetime.datetime(
+            int(self.kwargs["year"]),
+            int(self.kwargs["month"]),
+            int(self.kwargs["day"]),
+            int(self.kwargs["hour"]),
+            int(self.kwargs["minute"]),
+            int(self.kwargs["second"]),
+            tzinfo=pytz.UTC
+        )
+
+    def get_object(self, queryset=None):
+        event = get_object_or_404(Event, pk=self.kwargs["event_id"])
+        period = Period(
+            [event],
+            start=self.date_from_url,
+            end=self.date_from_url,
+        )
+
+        try:
+            return period.get_occurrences()[0]
+        except IndexError:
+            raise Http404
+
+    def get(self, request, *args, **kwargs):
+        self.object = self.get_object()
+        return super().get(request, *args, **kwargs)
+
     def get_context_data(self, **kwargs):
         context = super().get_context_data()
         context = {"event": self.object.event, "occurrence": self.object}

tests/test_views.py

@@ -663,3 +663,44 @@ def test_calendar_view_home(self):
         self.assertTrue(
             '<a href="/feed/calendar/upcoming/1/">Feed</a>' in response.content.decode()
         )
+
+
+class TestOccurrencePreview(TestCase):
+    def setUp(self):
+        self.rule = Rule.objects.create(frequency="DAILY")
+        self.calendar = Calendar.objects.create(name="MyCal", slug="MyCalSlug")
+        self.event = Event.objects.create(
+            title="Recent Event",
+            start=datetime.datetime(2008, 1, 5, 8, 0, tzinfo=pytz.utc),
+            end=datetime.datetime(2008, 1, 5, 9, 0, tzinfo=pytz.utc),
+            end_recurring_period=datetime.datetime(2008, 5, 5, 0, 0, tzinfo=pytz.utc),
+            rule=self.rule,
+            calendar=self.calendar,
+        )
+
+    def test_generates_preview(self):
+        url = reverse(
+            "occurrence_by_date",
+            kwargs={
+                "event_id": self.event.pk,
+                "year": 2008,
+                "month": 4,
+                "day": 20,
+                "hour": 8,
+                "minute": 30,
+                "second": 0,
+            }
+        )
+        response = self.client.get(url)
+        self.assertEqual(response.status_code, 200)
+        self.assertTemplateUsed(response, "schedule/occurrence.html")
+        self.assertEqual(response.context["event"], self.event)
+
+        occurrence = response.context["occurrence"]
+        self.assertEqual(occurrence.event, self.event)
+        self.assertEqual(
+            occurrence.start, datetime.datetime(2008, 4, 20, 8, 0, tzinfo=pytz.utc)
+        )
+        self.assertEqual(
+            occurrence.end, datetime.datetime(2008, 4, 20, 9, 0, tzinfo=pytz.utc)
+        )