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# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

"""
Module with utility functions for purging old action executions and
corresponding live action objects.
"""

import copy

from mongoengine.errors import InvalidQueryError

from st2common.constants import action as action_constants
from st2common.persistence.liveaction import LiveAction
from st2common.persistence.execution import ActionExecution

__all__ = [
    'purge_executions'
]

DONE_STATES = [action_constants.LIVEACTION_STATUS_SUCCEEDED,
               action_constants.LIVEACTION_STATUS_FAILED,
               action_constants.LIVEACTION_STATUS_TIMED_OUT,
               action_constants.LIVEACTION_STATUS_CANCELED]


def purge_executions(logger, timestamp, action_ref=None, purge_incomplete=False):
    """
    :param timestamp: Exections older than this timestamp will be deleted.
    :type timestamp: ``datetime.datetime

    :param action_ref: Only delete executions for the provided actions.
    :type action_ref: ``str``

    :param purge_incomplete: True to also delete executions which are not in a done state.
    :type purge_incomplete: ``bool``
    """
    if not timestamp:
        raise ValueError('Specify a valid timestamp to purge.')

    logger.info('Purging executions older than timestamp: %s' %
                timestamp.strftime('%Y-%m-%dT%H:%M:%S.%fZ'))

    filters = {}

    if purge_incomplete:
        filters['start_timestamp__lt'] = timestamp
    else:
        filters['end_timestamp__lt'] = timestamp
        filters['start_timestamp__lt'] = timestamp
        filters['status'] = {'$in': DONE_STATES}

    exec_filters = copy.copy(filters)
    if action_ref:
        exec_filters['action__ref'] = action_ref

    liveaction_filters = copy.deepcopy(filters)
    if action_ref:
        liveaction_filters['action'] = action_ref

    try:
        ActionExecution.delete_by_query(**exec_filters)
    except InvalidQueryError as e:
        msg = ('Bad query (%s) used to delete execution instances: %s'
               'Please contact support.' % (exec_filters, str(e)))
        raise InvalidQueryError(msg)
    except:
        logger.exception('Deletion of execution models failed for query with filters: %s.',
                         exec_filters)

    try:
        LiveAction.delete_by_query(**liveaction_filters)
    except InvalidQueryError as e:
        msg = ('Bad query (%s) used to delete liveaction instances: %s'
               'Please contact support.' % (liveaction_filters, str(e)))
        raise InvalidQueryError(msg)
    except:
        logger.exception('Deletion of liveaction models failed for query with filters: %s.',
                         liveaction_filters)

    zombie_execution_instances = len(ActionExecution.query(**exec_filters))
    zombie_liveaction_instances = len(LiveAction.query(**liveaction_filters))

    if (zombie_execution_instances > 0) or (zombie_liveaction_instances > 0):
        logger.error('Zombie execution instances left: %d.', zombie_execution_instances)
        logger.error('Zombie liveaction instances left: %s.', zombie_liveaction_instances)
    else:
        # Print stats
        logger.info('#### All execution models less than timestamp %s were deleted.', timestamp)

@@ -2538,24 +2538,199 @@
 action_ref%0A%0A
+    # TODO: Update this code to return statistics on deleted objects once we%0A    # upgrade to newer version of MongoDB where delete_by_query actually returns%0A    # some data%0A%0A
     try:%0A   

Add TODO annotation.