aodh/ceilometer/utils.py
Igor Degtiarov f67bce40fb Fix H405 violations and re-enable gating
H405 is a new rule in hacking 0.9, so fix new violations and
re-enable gating.

Change-Id: I61541fa0a9dc18ad938df54d56c65c972b151622
2014-07-01 13:41:27 +03:00

184 lines
6.0 KiB
Python

# 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 copy
import datetime
import decimal
import multiprocessing
import six
from ceilometer.openstack.common import timeutils
from ceilometer.openstack.common import units
def recursive_keypairs(d, separator=':'):
"""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, separator):
yield ('%s%s%s' % (name, separator, 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.
# in the special case of the list item itself being a dict,
# create an equivalent dict with a predictable insertion order
# to avoid inconsistencies in the message signature computation
# for equivalent payloads modulo ordering
first = lambda i: i[0]
m = map(lambda x: six.text_type(dict(sorted(x.items(), key=first))
if isinstance(x, dict)
else x).encode('utf-8'),
value)
yield name, list(m)
else:
yield name, value
def restore_nesting(d, separator=':'):
"""Unwinds a flattened dict to restore nesting."""
d = copy.copy(d) if any([separator in k for k in d.keys()]) else d
for k, v in d.items():
if separator in k:
top, rem = k.split(separator, 1)
nest = d[top] if isinstance(d.get(top), dict) else {}
nest[rem] = v
d[top] = restore_nesting(nest, separator)
del d[k]
return d
def dt_to_decimal(utc):
"""Datetime to Decimal.
Some databases don't store microseconds in datetime
so we always store as Decimal unixtime.
"""
if utc is None:
return None
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(units.M)
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)
def stringify_timestamps(data):
"""Stringify any datetimes in given dict."""
isa_timestamp = lambda v: isinstance(v, datetime.datetime)
return dict((k, v.isoformat() if isa_timestamp(v) else v)
for (k, v) in data.iteritems())
def dict_to_keyval(value, key_base=None):
"""Expand a given dict to its corresponding key-value pairs.
Generated keys are fully qualified, delimited using dot notation.
ie. key = 'key.child_key.grandchild_key[0]'
"""
val_iter, key_func = None, None
if isinstance(value, dict):
val_iter = value.iteritems()
key_func = lambda k: key_base + '.' + k if key_base else k
elif isinstance(value, (tuple, list)):
val_iter = enumerate(value)
key_func = lambda k: key_base + '[%d]' % k
if val_iter:
for k, v in val_iter:
key_gen = key_func(k)
if isinstance(v, dict) or isinstance(v, (tuple, list)):
for key_gen, v in dict_to_keyval(v, key_gen):
yield key_gen, v
else:
yield key_gen, v
def lowercase_keys(mapping):
"""Converts the values of the keys in mapping to lowercase."""
items = mapping.items()
for key, value in items:
del mapping[key]
mapping[key.lower()] = value
def lowercase_values(mapping):
"""Converts the values in the mapping dict to lowercase."""
items = mapping.items()
for key, value in items:
mapping[key] = value.lower()
def update_nested(original_dict, updates):
"""Updates the leaf nodes in a nest dict.
Updates occur without replacing entire sub-dicts.
"""
dict_to_update = copy.deepcopy(original_dict)
for key, value in updates.iteritems():
if isinstance(value, dict):
sub_dict = update_nested(dict_to_update.get(key, {}), value)
dict_to_update[key] = sub_dict
else:
dict_to_update[key] = updates[key]
return dict_to_update
def cpu_count():
try:
return multiprocessing.cpu_count() or 1
except NotImplementedError:
return 1
def uniq(dupes, attrs):
"""Exclude elements of dupes with a duplicated set of attribute values."""
key = lambda d: '/'.join([getattr(d, a) or '' for a in attrs])
keys = []
deduped = []
for d in dupes:
if key(d) not in keys:
deduped.append(d)
keys.append(key(d))
return deduped