From 6f0c9372362ce9150c384a0d7a4c0910901338d4 Mon Sep 17 00:00:00 2001
From: Ryan Petrello <rpetrell@redhat.com>
Date: Fri, 26 Jan 2018 14:24:54 -0500
Subject: [PATCH] don't allow distant DTSTART values for schedules; it's slow

see: https://github.com/ansible/ansible-tower/issues/7869
---
 awx/api/serializers.py                            |  4 ++--
 awx/main/models/schedules.py                      |  9 +++++++++
 awx/main/tests/functional/api/test_schedules.py   |  5 +++--
 awx/main/tests/functional/models/test_schedule.py | 13 +++++++++++++
 4 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/awx/api/serializers.py b/awx/api/serializers.py
index 0acdd2b34b..d1cdcd8a90 100644
--- a/awx/api/serializers.py
+++ b/awx/api/serializers.py
@@ -3927,8 +3927,8 @@ class SchedulePreviewSerializer(BaseSerializer):
                 raise serializers.ValidationError(_("COUNT > 999 is unsupported."))
         try:
             Schedule.rrulestr(rrule_value)
-        except Exception:
-            raise serializers.ValidationError(_("rrule parsing failed validation."))
+        except Exception as e:
+            raise serializers.ValidationError(_("rrule parsing failed validation: {}").format(e))
         return value
 
 
diff --git a/awx/main/models/schedules.py b/awx/main/models/schedules.py
index fcfc3ce88f..3dc9ac2814 100644
--- a/awx/main/models/schedules.py
+++ b/awx/main/models/schedules.py
@@ -166,6 +166,15 @@ class Schedule(CommonModel, LaunchTimeConfig):
                 rrule = rrule.replace(match_until.group('until'), 'UNTIL={}'.format(utc))
             kwargs['tzinfos']['TZI'] = timezone
         x = dateutil.rrule.rrulestr(rrule, **kwargs)
+
+        try:
+            first_event = x[0]
+            if first_event < now() - datetime.timedelta(days=365 * 5):
+                # For older DTSTART values, if there are more than 1000 recurrences...
+                if len(x[:1001]) > 1000:
+                    raise ValueError('RRULE values that yield more than 1000 events are not allowed.')
+        except IndexError:
+            pass
         return x
 
     def __unicode__(self):
diff --git a/awx/main/tests/functional/api/test_schedules.py b/awx/main/tests/functional/api/test_schedules.py
index f63bf37c65..c6cfc5d91a 100644
--- a/awx/main/tests/functional/api/test_schedules.py
+++ b/awx/main/tests/functional/api/test_schedules.py
@@ -59,9 +59,10 @@ def test_valid_survey_answer(post, admin_user, project, inventory, survey_spec_f
     ("DTSTART:20300308T050000Z RRULE:FREQ=YEARLY;INTERVAL=1;BYYEARDAY=100", "BYYEARDAY not supported"),  # noqa
     ("DTSTART:20300308T050000Z RRULE:FREQ=YEARLY;INTERVAL=1;BYWEEKNO=20", "BYWEEKNO not supported"),
     ("DTSTART:20300308T050000Z RRULE:FREQ=DAILY;INTERVAL=1;COUNT=2000", "COUNT > 999 is unsupported"),  # noqa
-    ("DTSTART:20300308T050000Z RRULE:FREQ=REGULARLY;INTERVAL=1", "rrule parsing failed validation"),  # noqa
-    ("DTSTART;TZID=America/New_York:30200308T050000Z RRULE:FREQ=DAILY;INTERVAL=1", "rrule parsing failed validation"),
+    ("DTSTART:20300308T050000Z RRULE:FREQ=REGULARLY;INTERVAL=1", "rrule parsing failed validation: invalid 'FREQ': REGULARLY"),  # noqa
+    ("DTSTART;TZID=America/New_York:20300308T050000Z RRULE:FREQ=DAILY;INTERVAL=1", "rrule parsing failed validation"),
     ("DTSTART:20300308T050000 RRULE:FREQ=DAILY;INTERVAL=1", "DTSTART cannot be a naive datetime"),
+    ("DTSTART:19700101T000000Z RRULE:FREQ=MINUTELY;INTERVAL=1", "more than 1000 events are not allowed"),  # noqa
 ])
 def test_invalid_rrules(post, admin_user, project, inventory, rrule, error):
     job_template = JobTemplate.objects.create(
diff --git a/awx/main/tests/functional/models/test_schedule.py b/awx/main/tests/functional/models/test_schedule.py
index 2df0e479e3..c4c6019503 100644
--- a/awx/main/tests/functional/models/test_schedule.py
+++ b/awx/main/tests/functional/models/test_schedule.py
@@ -192,3 +192,16 @@ def test_dst_phantom_hour(job_template):
 
     # 3/10/30 @ 2:30AM is skipped because it _doesn't exist_ <cue twilight zone music>
     assert str(s.next_run) == '2030-03-17 06:30:00+00:00'
+
+
+@pytest.mark.django_db
+def test_beginning_of_time(job_template):
+    # ensure that really large generators don't have performance issues
+    rrule = 'DTSTART:19700101T000000Z RRULE:FREQ=MINUTELY;INTERVAL=1'
+    s = Schedule(
+        name='Some Schedule',
+        rrule=rrule,
+        unified_job_template=job_template
+    )
+    with pytest.raises(ValueError):
+        s.save()