neutron/neutron/services/timestamp/timestamp_db.py

108 lines
4.0 KiB
Python

# Copyright 2015 HuaWei Technologies.
#
# Licensed 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.
from neutron_lib import exceptions as n_exc
from oslo_utils import timeutils
from sqlalchemy.orm import session as se
from neutron.db import _model_query as model_query
from neutron.db import _resource_extend as resource_extend
from neutron.db import api as db_api
from neutron.db import standard_attr
CHANGED_SINCE = 'changed_since'
TIME_FORMAT_WHOLE_SECONDS = '%Y-%m-%dT%H:%M:%S'
def _change_since_result_filter_hook(query, filters):
# this block is for change_since query
# we get the changed_since string from filters.
# And translate it from string to datetime type.
# Then compare with the timestamp in db which has
# datetime type.
values = filters and filters.get(CHANGED_SINCE, [])
if not values:
return query
data = filters[CHANGED_SINCE][0]
try:
changed_since_string = timeutils.parse_isotime(data)
except Exception:
msg = ("The input %s must be in the "
"following format: YYYY-MM-DDTHH:MM:SSZ") % CHANGED_SINCE
raise n_exc.InvalidInput(error_message=msg)
changed_since = (timeutils.
normalize_time(changed_since_string))
target_model_class = query.column_descriptions[0]['type']
query = query.join(standard_attr.StandardAttribute,
target_model_class.standard_attr_id ==
standard_attr.StandardAttribute.id).filter(
standard_attr.StandardAttribute.updated_at >=
changed_since)
return query
def _update_timestamp(session, context, instances):
objs_list = session.new.union(session.dirty)
while objs_list:
obj = objs_list.pop()
if (isinstance(obj, standard_attr.HasStandardAttributes) and
obj.standard_attr_id):
obj.updated_at = timeutils.utcnow()
def _format_timestamp(resource_db, result):
result['created_at'] = (resource_db.created_at.
strftime(TIME_FORMAT_WHOLE_SECONDS)) + 'Z'
result['updated_at'] = (resource_db.updated_at.
strftime(TIME_FORMAT_WHOLE_SECONDS)) + 'Z'
def _add_timestamp(mapper, _conn, target):
if not target.created_at and not target.updated_at:
time = timeutils.utcnow()
for field in ['created_at', 'updated_at']:
setattr(target, field, time)
return target
@resource_extend.has_resource_extenders
class TimeStamp_db_mixin(object):
"""Mixin class to add Time Stamp methods."""
def __new__(cls, *args, **kwargs):
rs_model_maps = standard_attr.get_standard_attr_resource_model_map()
for model in rs_model_maps.values():
model_query.register_hook(
model,
"change_since_query",
query_hook=None,
filter_hook=None,
result_filters=_change_since_result_filter_hook)
return super(TimeStamp_db_mixin, cls).__new__(cls, *args, **kwargs)
def register_db_events(self):
listen = db_api.sqla_listen
listen(standard_attr.StandardAttribute, 'before_insert',
_add_timestamp)
listen(se.Session, 'before_flush', _update_timestamp)
@staticmethod
@resource_extend.extends(
list(standard_attr.get_standard_attr_resource_model_map()))
def _extend_resource_dict_timestamp(resource_res, resource_db):
if (resource_db and resource_db.created_at and
resource_db.updated_at):
_format_timestamp(resource_db, resource_res)