aodh/ceilometer/utils.py
Sandy Walsh 2b15389317 Add Event methods to db api.
Start of adding the ability to store raw events in Ceilometer.
Query Filter mechanism is crude for now. Need to find a more expressive
grammar than this EventFilter thing.

Change-Id: I3c64e3858df756d93dd5bf3c6c9651be25cd2b55
Blueprint: add-event-table
2013-05-22 14:23:03 -03:00

98 lines
3.2 KiB
Python

# vim: tabstop=4 shiftwidth=4 softtabstop=4
# Copyright 2010 United States Government as represented by the
# Administrator of the National Aeronautics and Space Administration.
# Copyright 2011 Justin Santa Barbara
# All Rights Reserved.
#
# 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.
"""Utilities and helper functions."""
import calendar
import datetime
import decimal
import os
from ceilometer.openstack.common import timeutils
def read_cached_file(filename, cache_info, reload_func=None):
"""Read from a file if it has been modified.
:param cache_info: dictionary to hold opaque cache.
:param reload_func: optional function to be called with data when
file is reloaded due to a modification.
:returns: data from file
"""
mtime = os.path.getmtime(filename)
if not cache_info or mtime != cache_info.get('mtime'):
with open(filename) as fap:
cache_info['data'] = fap.read()
cache_info['mtime'] = mtime
if reload_func:
reload_func(cache_info['data'])
return cache_info['data']
def recursive_keypairs(d):
"""Generator that produces sequence of keypairs for nested dictionaries.
"""
for name, value in sorted(d.iteritems()):
if isinstance(value, dict):
for subname, subvalue in recursive_keypairs(value):
yield ('%s:%s' % (name, subname), subvalue)
elif isinstance(value, (tuple, list)):
# When doing a pair of JSON encode/decode operations to the tuple,
# the tuple would become list. So we have to generate the value as
# list here.
yield name, list(map(lambda x: unicode(x).encode('utf-8'),
value))
else:
yield name, value
def dt_to_decimal(utc):
"""Datetime to Decimal.
Some databases don't store microseconds in datetime
so we always store as Decimal unixtime.
"""
decimal.getcontext().prec = 30
return decimal.Decimal(str(calendar.timegm(utc.utctimetuple()))) + \
(decimal.Decimal(str(utc.microsecond)) /
decimal.Decimal("1000000.0"))
def decimal_to_dt(dec):
"""Return a datetime from Decimal unixtime format.
"""
if dec is None:
return None
integer = int(dec)
micro = (dec - decimal.Decimal(integer)) * decimal.Decimal(1000000)
daittyme = datetime.datetime.utcfromtimestamp(integer)
return daittyme.replace(microsecond=int(round(micro)))
def sanitize_timestamp(timestamp):
"""Return a naive utc datetime object."""
if not timestamp:
return timestamp
if not isinstance(timestamp, datetime.datetime):
timestamp = timeutils.parse_isotime(timestamp)
return timeutils.normalize_time(timestamp)