bump python-dateutil to latest

this change provides support for numerous bug fixes, along with
support for parsing TZINFO= from rrule strings

related: https://github.com/ansible/ansible-tower/issues/823
related: https://github.com/dateutil/dateutil/issues/614

awx/main/models/schedules.py

@@ -1,11 +1,10 @@
 # Copyright (c) 2015 Ansible, Inc.
 # All Rights Reserved.
 
-import re
 import logging
 import datetime
 import dateutil.rrule
-from dateutil.tz import gettz, datetime_exists
+from dateutil.tz import datetime_exists
 
 # Django
 from django.db import models
@@ -57,10 +56,6 @@ class ScheduleManager(ScheduleFilterMethods, models.Manager):
 
 class Schedule(CommonModel, LaunchTimeConfig):
 
-    TZID_REGEX = re.compile(
-        "^(DTSTART;TZID=(?P<tzid>[^:]+)(?P<stamp>\:[0-9]+T[0-9]+))(?P<rrule> .*)$"
-    )
-
     class Meta:
         app_label = 'main'
         ordering = ['-next_run']
@@ -103,51 +98,23 @@ class Schedule(CommonModel, LaunchTimeConfig):
     def rrulestr(cls, rrule, **kwargs):
         """
         Apply our own custom rrule parsing logic to support TZID=
-
-        python-dateutil doesn't _natively_ support `DTSTART;TZID=`; this
-        function parses out the TZID= component and uses it to produce the
-        `tzinfos` keyword argument to `dateutil.rrule.rrulestr()`. In this
-        way, we translate:
-
-        DTSTART;TZID=America/New_York:20180601T120000 RRULE:FREQ=DAILY;INTERVAL=1
-
-        ...into...
-
-        DTSTART:20180601T120000TZID RRULE:FREQ=DAILY;INTERVAL=1
-
-        ...and we pass a hint about the local timezone to dateutil's parser:
-        `dateutil.rrule.rrulestr(rrule, {
-            'tzinfos': {
-                'TZID': dateutil.tz.gettz('America/New_York')
-              }
-         })`
-
-        it's likely that we can remove the custom code that performs this
-        parsing if TZID= gains support in upstream dateutil:
-        https://github.com/dateutil/dateutil/pull/619
         """
         kwargs['forceset'] = True
-        kwargs['tzinfos'] = {x: dateutil.tz.tzutc() for x in dateutil.parser.parserinfo().UTCZONE}
-        match = cls.TZID_REGEX.match(rrule)
-        if match is not None:
-            rrule = cls.TZID_REGEX.sub("DTSTART\g<stamp>TZI\g<rrule>", rrule)
-            timezone = gettz(match.group('tzid'))
-            kwargs['tzinfos']['TZI'] = timezone
         x = dateutil.rrule.rrulestr(rrule, **kwargs)
 
         for r in x._rrule:
+            if r._dtstart and r._dtstart.tzinfo is None:
+                raise ValueError(
+                    'A valid TZID must be provided (e.g., America/New_York)'
+                )
+
             if r._dtstart and r._until:
+                # If https://github.com/dateutil/dateutil/pull/634 ever makes
+                # it into a python-dateutil release, we could remove this block.
                 if all((
                     r._dtstart.tzinfo != dateutil.tz.tzlocal(),
                     r._until.tzinfo != dateutil.tz.tzutc(),
                 )):
-                    # According to RFC5545 Section 3.3.10:
-                    # https://tools.ietf.org/html/rfc5545#section-3.3.10
-                    #
-                    # > If the "DTSTART" property is specified as a date with UTC
-                    # > time or a date with local time and time zone reference,
-                    # > then the UNTIL rule part MUST be specified as a date with
-                    # > UTC time.
                     raise ValueError('RRULE UNTIL values must be specified in UTC')
 
         if 'MINUTELY' in rrule or 'HOURLY' in rrule:

awx/main/tests/functional/api/test_schedules.py

@@ -65,6 +65,7 @@ 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;TZID=US-Eastern:19961105T090000 RRULE:FREQ=MINUTELY;INTERVAL=10;COUNT=5", "A valid TZID must be provided"),  # noqa
     ("DTSTART:20300308T050000Z RRULE:FREQ=REGULARLY;INTERVAL=1", "rrule parsing failed validation: invalid 'FREQ': REGULARLY"),  # noqa
     ("DTSTART:20030925T104941Z RRULE:FREQ=DAILY;INTERVAL=10;COUNT=500;UNTIL=20040925T104941Z", "RRULE may not contain both COUNT and UNTIL"),  # noqa
     ("DTSTART;TZID=America/New_York:20300308T050000Z RRULE:FREQ=DAILY;INTERVAL=1", "rrule parsing failed validation"),

requirements/requirements.in

@@ -38,6 +38,7 @@ pycrypto==2.6.1
 pygerduty==0.37.0
 pyOpenSSL==17.5.0
 pyparsing==2.2.0
+python-dateutil==2.7.0  # contains support for TZINFO= parsing
 python-logstash==0.4.6
 python-memcached==1.59
 python-radius==1.0

requirements/requirements.txt

@@ -182,7 +182,7 @@ pyjwt==1.6.0              # via adal, social-auth-core, twilio
 pyopenssl==17.5.0
 pyparsing==2.2.0
 pyrad==2.1                # via django-radius
-python-dateutil==2.6.1    # via adal, azure-cosmosdb-table, azure-storage-common, botocore
+python-dateutil==2.7.0
 python-ldap==2.5.2        # via django-auth-ldap
 python-logstash==0.4.6
 python-memcached==1.59