Error in alarm evaluation when timezone in time_constraints is specified

[Rikimaru Honjo]

Define a alarm with timezone in time_constraints is specified as follws:

curl -v -X POST -H 'X-Auth-Token:5093deed81f9418a9efcecccf9cf2e4a' -H 'Content-type: application/json' -d '{"alarm_actions": ["http://site:8000/alarm"], "name": "TestAlarm3", "threshold_rule": {"meter_name":"image.size", "period":10, "comparison_operator":"gt", "threshold":1.0, "statistic": "avg" }, "type": "threshold", "time_constraints": [{"description": "nightly build every night at 23h for 3 hours", "duration": 10800, "name": "SampleConstraint", "start": "0 23 * * *", "timezone": "Europe/Ljubljana"}]}' http://localhost:8777/v2/alarms

The following error occurs when Alarm evaluator tries to evaluate the alarm:

2014-06-27 15:06:36.017 7694 ERROR ceilometer.alarm.service [-] alarm evaluation cycle failed
2014-06-27 15:06:36.017 7694 TRACE ceilometer.alarm.service Traceback (most recent call last):
2014-06-27 15:06:36.017 7694 TRACE ceilometer.alarm.service File "/usr/local/lib/python2.7/dist-packages/ceilometer/alarm/service.py", line 93, in _evaluate_assigned_alarms
2014-06-27 15:06:36.017 7694 TRACE ceilometer.alarm.service self._evaluate_alarm(alarm)
2014-06-27 15:06:36.017 7694 TRACE ceilometer.alarm.service File "/usr/local/lib/python2.7/dist-packages/ceilometer/alarm/service.py", line 105, in _evaluate_alarm
2014-06-27 15:06:36.017 7694 TRACE ceilometer.alarm.service self.evaluators[alarm.type].obj.evaluate(alarm)
2014-06-27 15:06:36.017 7694 TRACE ceilometer.alarm.service File "/usr/local/lib/python2.7/dist-packages/ceilometer/alarm/evaluator/threshold.py", line 175, in evaluate
2014-06-27 15:06:36.017 7694 TRACE ceilometer.alarm.service if not self.within_time_constraint(alarm):
2014-06-27 15:06:36.017 7694 TRACE ceilometer.alarm.service File "/usr/local/lib/python2.7/dist-packages/ceilometer/alarm/evaluator/__init__.py", line 95, in within_time_constraint
2014-06-27 15:06:36.017 7694 TRACE ceilometer.alarm.service now_tz = now_utc.astimezone(tz) if tz else now_utc
2014-06-27 15:06:36.017 7694 TRACE ceilometer.alarm.service ValueError: astimezone() cannot be applied to a naive datetime
2014-06-27 15:06:36.017 7694 TRACE ceilometer.alarm.service

The error says that astimezone() cannot be applied to a native datetime (now_utc).
Thus, making now_utc to non-native (aware object) will solve the problem.
The following code will do.

>>> import datetime
>>> now_utc = datetime.datetime.utcnow()
>>> print now_utc.tzinfo
None
>>> import pytz
>>> tz = pytz.timezone('Europe/Ljubljana')
>>> now_tz = now_utc.astimezone(tz)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: astimezone() cannot be applied to a naive datetime
>>>
>>> utc = pytz.timezone('UTC')
>>> now_tz = now_utc.replace(tzinfo=utc).astimezone(tz)
>>>

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/107332

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/107332
Committed: https://git.openstack.org/cgit/openstack/ceilometer/commit/?id=667e4643122761b899a0824662a644ba7253cef8
Submitter: Jenkins
Branch: master

commit 667e4643122761b899a0824662a644ba7253cef8
Author: Rikimaru Honjo <email address hidden>
Date: Thu Jul 17 19:59:23 2014 +0900

    Replace datetime of time_constraints by aware object

    Error occurs in alarm evaluation when timezone in time_constraints is specified,
    because astimezone() cannot be applied to a native datetime.

    Making datetime to non-native (aware object) will solve the problem.

    Change-Id: Ic0de4a5b32865bbe330c2936f14adf59168eefe5
    Closes-bug: #1342676