1006 lines
34 KiB
Python
1006 lines
34 KiB
Python
|
# -*- coding: UTF-8 -*-
|
||
|
|
||
|
"""
|
||
|
win32timezone:
|
||
|
Module for handling datetime.tzinfo time zones using the windows
|
||
|
registry for time zone information. The time zone names are dependent
|
||
|
on the registry entries defined by the operating system.
|
||
|
|
||
|
This module may be tested using the doctest module.
|
||
|
|
||
|
Written by Jason R. Coombs (jaraco@jaraco.com).
|
||
|
Copyright © 2003-2012.
|
||
|
All Rights Reserved.
|
||
|
|
||
|
This module is licenced for use in Mark Hammond's pywin32
|
||
|
library under the same terms as the pywin32 library.
|
||
|
|
||
|
To use this time zone module with the datetime module, simply pass
|
||
|
the TimeZoneInfo object to the datetime constructor. For example,
|
||
|
|
||
|
>>> import win32timezone, datetime
|
||
|
>>> assert 'Mountain Standard Time' in win32timezone.TimeZoneInfo.get_sorted_time_zone_names()
|
||
|
>>> MST = win32timezone.TimeZoneInfo('Mountain Standard Time')
|
||
|
>>> now = datetime.datetime.now(MST)
|
||
|
|
||
|
The now object is now a time-zone aware object, and daylight savings-
|
||
|
aware methods may be called on it.
|
||
|
|
||
|
>>> now.utcoffset() in (datetime.timedelta(-1, 61200), datetime.timedelta(-1, 64800))
|
||
|
True
|
||
|
|
||
|
(note that the result of utcoffset call will be different based on when now was
|
||
|
generated, unless standard time is always used)
|
||
|
|
||
|
>>> now = datetime.datetime.now(TimeZoneInfo('Mountain Standard Time', True))
|
||
|
>>> now.utcoffset()
|
||
|
datetime.timedelta(-1, 61200)
|
||
|
|
||
|
>>> aug2 = datetime.datetime(2003, 8, 2, tzinfo = MST)
|
||
|
>>> tuple(aug2.utctimetuple())
|
||
|
(2003, 8, 2, 6, 0, 0, 5, 214, 0)
|
||
|
>>> nov2 = datetime.datetime(2003, 11, 25, tzinfo = MST)
|
||
|
>>> tuple(nov2.utctimetuple())
|
||
|
(2003, 11, 25, 7, 0, 0, 1, 329, 0)
|
||
|
|
||
|
To convert from one timezone to another, just use the astimezone method.
|
||
|
|
||
|
>>> aug2.isoformat()
|
||
|
'2003-08-02T00:00:00-06:00'
|
||
|
>>> aug2est = aug2.astimezone(win32timezone.TimeZoneInfo('Eastern Standard Time'))
|
||
|
>>> aug2est.isoformat()
|
||
|
'2003-08-02T02:00:00-04:00'
|
||
|
|
||
|
calling the displayName member will return the display name as set in the
|
||
|
registry.
|
||
|
|
||
|
>>> est = win32timezone.TimeZoneInfo('Eastern Standard Time')
|
||
|
>>> str(est.displayName)
|
||
|
'(UTC-05:00) Eastern Time (US & Canada)'
|
||
|
|
||
|
>>> gmt = win32timezone.TimeZoneInfo('GMT Standard Time', True)
|
||
|
>>> str(gmt.displayName)
|
||
|
'(UTC+00:00) Dublin, Edinburgh, Lisbon, London'
|
||
|
|
||
|
To get the complete list of available time zone keys,
|
||
|
>>> zones = win32timezone.TimeZoneInfo.get_all_time_zones()
|
||
|
|
||
|
If you want to get them in an order that's sorted longitudinally
|
||
|
>>> zones = win32timezone.TimeZoneInfo.get_sorted_time_zones()
|
||
|
|
||
|
TimeZoneInfo now supports being pickled and comparison
|
||
|
>>> import pickle
|
||
|
>>> tz = win32timezone.TimeZoneInfo('China Standard Time')
|
||
|
>>> tz == pickle.loads(pickle.dumps(tz))
|
||
|
True
|
||
|
|
||
|
It's possible to construct a TimeZoneInfo from a TimeZoneDescription
|
||
|
including the currently-defined zone.
|
||
|
>>> tz = win32timezone.TimeZoneInfo(TimeZoneDefinition.current())
|
||
|
>>> tz == pickle.loads(pickle.dumps(tz))
|
||
|
True
|
||
|
|
||
|
>>> aest = win32timezone.TimeZoneInfo('AUS Eastern Standard Time')
|
||
|
>>> est = win32timezone.TimeZoneInfo('E. Australia Standard Time')
|
||
|
>>> dt = datetime.datetime(2006, 11, 11, 1, 0, 0, tzinfo = aest)
|
||
|
>>> estdt = dt.astimezone(est)
|
||
|
>>> estdt.strftime('%Y-%m-%d %H:%M:%S')
|
||
|
'2006-11-11 00:00:00'
|
||
|
|
||
|
>>> dt = datetime.datetime(2007, 1, 12, 1, 0, 0, tzinfo = aest)
|
||
|
>>> estdt = dt.astimezone(est)
|
||
|
>>> estdt.strftime('%Y-%m-%d %H:%M:%S')
|
||
|
'2007-01-12 00:00:00'
|
||
|
|
||
|
>>> dt = datetime.datetime(2007, 6, 13, 1, 0, 0, tzinfo = aest)
|
||
|
>>> estdt = dt.astimezone(est)
|
||
|
>>> estdt.strftime('%Y-%m-%d %H:%M:%S')
|
||
|
'2007-06-13 01:00:00'
|
||
|
|
||
|
Microsoft now has a patch for handling time zones in 2007 (see
|
||
|
http://support.microsoft.com/gp/cp_dst)
|
||
|
|
||
|
As a result, patched systems will give an incorrect result for
|
||
|
dates prior to the designated year except for Vista and its
|
||
|
successors, which have dynamic time zone support.
|
||
|
>>> nov2_pre_change = datetime.datetime(2003, 11, 2, tzinfo = MST)
|
||
|
>>> old_response = (2003, 11, 2, 7, 0, 0, 6, 306, 0)
|
||
|
>>> incorrect_patch_response = (2003, 11, 2, 6, 0, 0, 6, 306, 0)
|
||
|
>>> pre_response = nov2_pre_change.utctimetuple()
|
||
|
>>> pre_response in (old_response, incorrect_patch_response)
|
||
|
True
|
||
|
|
||
|
Furthermore, unpatched systems pre-Vista will give an incorrect
|
||
|
result for dates after 2007.
|
||
|
>>> nov2_post_change = datetime.datetime(2007, 11, 2, tzinfo = MST)
|
||
|
>>> incorrect_unpatched_response = (2007, 11, 2, 7, 0, 0, 4, 306, 0)
|
||
|
>>> new_response = (2007, 11, 2, 6, 0, 0, 4, 306, 0)
|
||
|
>>> post_response = nov2_post_change.utctimetuple()
|
||
|
>>> post_response in (new_response, incorrect_unpatched_response)
|
||
|
True
|
||
|
|
||
|
|
||
|
There is a function you can call to get some capabilities of the time
|
||
|
zone data.
|
||
|
>>> caps = GetTZCapabilities()
|
||
|
>>> isinstance(caps, dict)
|
||
|
True
|
||
|
>>> 'MissingTZPatch' in caps
|
||
|
True
|
||
|
>>> 'DynamicTZSupport' in caps
|
||
|
True
|
||
|
|
||
|
>>> both_dates_correct = (pre_response == old_response and post_response == new_response)
|
||
|
>>> old_dates_wrong = (pre_response == incorrect_patch_response)
|
||
|
>>> new_dates_wrong = (post_response == incorrect_unpatched_response)
|
||
|
|
||
|
>>> caps['DynamicTZSupport'] == both_dates_correct
|
||
|
True
|
||
|
|
||
|
>>> (not caps['DynamicTZSupport'] and caps['MissingTZPatch']) == new_dates_wrong
|
||
|
True
|
||
|
|
||
|
>>> (not caps['DynamicTZSupport'] and not caps['MissingTZPatch']) == old_dates_wrong
|
||
|
True
|
||
|
|
||
|
This test helps ensure language support for unicode characters
|
||
|
>>> x = TIME_ZONE_INFORMATION(0, u'français')
|
||
|
|
||
|
|
||
|
Test conversion from one time zone to another at a DST boundary
|
||
|
===============================================================
|
||
|
|
||
|
>>> tz_hi = TimeZoneInfo('Hawaiian Standard Time')
|
||
|
>>> tz_pac = TimeZoneInfo('Pacific Standard Time')
|
||
|
>>> time_before = datetime.datetime(2011, 11, 5, 15, 59, 59, tzinfo=tz_hi)
|
||
|
>>> tz_hi.utcoffset(time_before)
|
||
|
datetime.timedelta(-1, 50400)
|
||
|
>>> tz_hi.dst(time_before)
|
||
|
datetime.timedelta(0)
|
||
|
|
||
|
Hawaii doesn't need dynamic TZ info
|
||
|
>>> getattr(tz_hi, 'dynamicInfo', None)
|
||
|
|
||
|
Here's a time that gave some trouble as reported in #3523104
|
||
|
because one minute later, the equivalent UTC time changes from DST
|
||
|
in the U.S.
|
||
|
>>> dt_hi = datetime.datetime(2011, 11, 5, 15, 59, 59, 0, tzinfo=tz_hi)
|
||
|
>>> dt_hi.timetuple()
|
||
|
time.struct_time(tm_year=2011, tm_mon=11, tm_mday=5, tm_hour=15, tm_min=59, tm_sec=59, tm_wday=5, tm_yday=309, tm_isdst=0)
|
||
|
>>> dt_hi.utctimetuple()
|
||
|
time.struct_time(tm_year=2011, tm_mon=11, tm_mday=6, tm_hour=1, tm_min=59, tm_sec=59, tm_wday=6, tm_yday=310, tm_isdst=0)
|
||
|
|
||
|
Convert the time to pacific time.
|
||
|
>>> dt_pac = dt_hi.astimezone(tz_pac)
|
||
|
>>> dt_pac.timetuple()
|
||
|
time.struct_time(tm_year=2011, tm_mon=11, tm_mday=5, tm_hour=18, tm_min=59, tm_sec=59, tm_wday=5, tm_yday=309, tm_isdst=1)
|
||
|
|
||
|
Notice that the UTC time is almost 2am.
|
||
|
>>> dt_pac.utctimetuple()
|
||
|
time.struct_time(tm_year=2011, tm_mon=11, tm_mday=6, tm_hour=1, tm_min=59, tm_sec=59, tm_wday=6, tm_yday=310, tm_isdst=0)
|
||
|
|
||
|
Now do the same tests one minute later in Hawaii.
|
||
|
>>> time_after = datetime.datetime(2011, 11, 5, 16, 0, 0, 0, tzinfo=tz_hi)
|
||
|
>>> tz_hi.utcoffset(time_after)
|
||
|
datetime.timedelta(-1, 50400)
|
||
|
>>> tz_hi.dst(time_before)
|
||
|
datetime.timedelta(0)
|
||
|
|
||
|
>>> dt_hi = datetime.datetime(2011, 11, 5, 16, 0, 0, 0, tzinfo=tz_hi)
|
||
|
>>> print dt_hi.timetuple()
|
||
|
time.struct_time(tm_year=2011, tm_mon=11, tm_mday=5, tm_hour=16, tm_min=0, tm_sec=0, tm_wday=5, tm_yday=309, tm_isdst=0)
|
||
|
>>> print dt_hi.utctimetuple()
|
||
|
time.struct_time(tm_year=2011, tm_mon=11, tm_mday=6, tm_hour=2, tm_min=0, tm_sec=0, tm_wday=6, tm_yday=310, tm_isdst=0)
|
||
|
|
||
|
According to the docs, this is what astimezone does.
|
||
|
>>> utc = (dt_hi - dt_hi.utcoffset()).replace(tzinfo=tz_pac)
|
||
|
>>> utc
|
||
|
datetime.datetime(2011, 11, 6, 2, 0, tzinfo=TimeZoneInfo('Pacific Standard Time'))
|
||
|
>>> tz_pac.fromutc(utc) == dt_hi.astimezone(tz_pac)
|
||
|
True
|
||
|
>>> tz_pac.fromutc(utc)
|
||
|
datetime.datetime(2011, 11, 5, 19, 0, tzinfo=TimeZoneInfo('Pacific Standard Time'))
|
||
|
|
||
|
Make sure the converted time is correct.
|
||
|
>>> dt_pac = dt_hi.astimezone(tz_pac)
|
||
|
>>> dt_pac.timetuple()
|
||
|
time.struct_time(tm_year=2011, tm_mon=11, tm_mday=5, tm_hour=19, tm_min=0, tm_sec=0, tm_wday=5, tm_yday=309, tm_isdst=1)
|
||
|
>>> dt_pac.utctimetuple()
|
||
|
time.struct_time(tm_year=2011, tm_mon=11, tm_mday=6, tm_hour=2, tm_min=0, tm_sec=0, tm_wday=6, tm_yday=310, tm_isdst=0)
|
||
|
|
||
|
Check some internal methods
|
||
|
>>> tz_pac._getStandardBias(datetime.datetime(2011, 1, 1))
|
||
|
datetime.timedelta(0, 28800)
|
||
|
>>> tz_pac._getDaylightBias(datetime.datetime(2011, 1, 1))
|
||
|
datetime.timedelta(0, 25200)
|
||
|
|
||
|
Test the offsets
|
||
|
>>> offset = tz_pac.utcoffset(datetime.datetime(2011, 11, 6, 2, 0))
|
||
|
>>> offset == datetime.timedelta(hours=-8)
|
||
|
True
|
||
|
>>> dst_offset = tz_pac.dst(datetime.datetime(2011, 11, 6, 2, 0) + offset)
|
||
|
>>> dst_offset == datetime.timedelta(hours=1)
|
||
|
True
|
||
|
>>> (offset + dst_offset) == datetime.timedelta(hours=-7)
|
||
|
True
|
||
|
|
||
|
|
||
|
Test offsets that occur right at the DST changeover
|
||
|
>>> datetime.datetime.utcfromtimestamp(1320570000).replace(
|
||
|
... tzinfo=TimeZoneInfo.utc()).astimezone(tz_pac)
|
||
|
datetime.datetime(2011, 11, 6, 1, 0, tzinfo=TimeZoneInfo('Pacific Standard Time'))
|
||
|
|
||
|
"""
|
||
|
from __future__ import generators
|
||
|
|
||
|
__author__ = 'Jason R. Coombs <jaraco@jaraco.com>'
|
||
|
|
||
|
import winreg
|
||
|
import struct
|
||
|
import datetime
|
||
|
import win32api
|
||
|
import re
|
||
|
import operator
|
||
|
from itertools import count
|
||
|
|
||
|
import logging
|
||
|
log = logging.getLogger(__file__)
|
||
|
|
||
|
|
||
|
# A couple of objects for working with objects as if they were native C-type
|
||
|
# structures.
|
||
|
class _SimpleStruct(object):
|
||
|
_fields_ = None # must be overridden by subclasses
|
||
|
|
||
|
def __init__(self, *args, **kw):
|
||
|
for i, (name, typ) in enumerate(self._fields_):
|
||
|
def_arg = None
|
||
|
if i < len(args):
|
||
|
def_arg = args[i]
|
||
|
if name in kw:
|
||
|
def_arg = kw[name]
|
||
|
if def_arg is not None:
|
||
|
if not isinstance(def_arg, tuple):
|
||
|
def_arg = (def_arg,)
|
||
|
else:
|
||
|
def_arg = ()
|
||
|
if len(def_arg) == 1 and isinstance(def_arg[0], typ):
|
||
|
# already an object of this type.
|
||
|
# XXX - should copy.copy???
|
||
|
def_val = def_arg[0]
|
||
|
else:
|
||
|
def_val = typ(*def_arg)
|
||
|
setattr(self, name, def_val)
|
||
|
|
||
|
def field_names(self):
|
||
|
return [f[0] for f in self._fields_]
|
||
|
|
||
|
def __eq__(self, other):
|
||
|
if not hasattr(other, "_fields_"):
|
||
|
return False
|
||
|
if self._fields_ != other._fields_:
|
||
|
return False
|
||
|
for name, _ in self._fields_:
|
||
|
if getattr(self, name) != getattr(other, name):
|
||
|
return False
|
||
|
return True
|
||
|
|
||
|
def __ne__(self, other):
|
||
|
return not self.__eq__(other)
|
||
|
|
||
|
|
||
|
class SYSTEMTIME(_SimpleStruct):
|
||
|
_fields_ = [
|
||
|
('year', int),
|
||
|
('month', int),
|
||
|
('day_of_week', int),
|
||
|
('day', int),
|
||
|
('hour', int),
|
||
|
('minute', int),
|
||
|
('second', int),
|
||
|
('millisecond', int),
|
||
|
]
|
||
|
|
||
|
|
||
|
class TIME_ZONE_INFORMATION(_SimpleStruct):
|
||
|
_fields_ = [
|
||
|
('bias', int),
|
||
|
('standard_name', str),
|
||
|
('standard_start', SYSTEMTIME),
|
||
|
('standard_bias', int),
|
||
|
('daylight_name', str),
|
||
|
('daylight_start', SYSTEMTIME),
|
||
|
('daylight_bias', int),
|
||
|
]
|
||
|
|
||
|
|
||
|
class DYNAMIC_TIME_ZONE_INFORMATION(_SimpleStruct):
|
||
|
_fields_ = TIME_ZONE_INFORMATION._fields_ + [
|
||
|
('key_name', str),
|
||
|
('dynamic_daylight_time_disabled', bool),
|
||
|
]
|
||
|
|
||
|
|
||
|
class TimeZoneDefinition(DYNAMIC_TIME_ZONE_INFORMATION):
|
||
|
"""
|
||
|
A time zone definition class based on the win32
|
||
|
DYNAMIC_TIME_ZONE_INFORMATION structure.
|
||
|
|
||
|
Describes a bias against UTC (bias), and two dates at which a separate
|
||
|
additional bias applies (standard_bias and daylight_bias).
|
||
|
"""
|
||
|
|
||
|
def __init__(self, *args, **kwargs):
|
||
|
"""
|
||
|
Try to construct a TimeZoneDefinition from
|
||
|
a) [DYNAMIC_]TIME_ZONE_INFORMATION args
|
||
|
b) another TimeZoneDefinition
|
||
|
c) a byte structure (using _from_bytes)
|
||
|
"""
|
||
|
try:
|
||
|
super(TimeZoneDefinition, self).__init__(*args, **kwargs)
|
||
|
return
|
||
|
except (TypeError, ValueError):
|
||
|
pass
|
||
|
|
||
|
try:
|
||
|
self.__init_from_other(*args, **kwargs)
|
||
|
return
|
||
|
except TypeError:
|
||
|
pass
|
||
|
|
||
|
try:
|
||
|
self.__init_from_bytes(*args, **kwargs)
|
||
|
return
|
||
|
except TypeError:
|
||
|
pass
|
||
|
|
||
|
raise TypeError("Invalid arguments for %s" % self.__class__)
|
||
|
|
||
|
def __init_from_bytes(
|
||
|
self, bytes, standard_name='', daylight_name='', key_name='',
|
||
|
daylight_disabled=False):
|
||
|
format = '3l8h8h'
|
||
|
components = struct.unpack(format, bytes)
|
||
|
bias, standard_bias, daylight_bias = components[:3]
|
||
|
standard_start = SYSTEMTIME(*components[3:11])
|
||
|
daylight_start = SYSTEMTIME(*components[11:19])
|
||
|
super(TimeZoneDefinition, self).__init__(
|
||
|
bias,
|
||
|
standard_name, standard_start, standard_bias,
|
||
|
daylight_name, daylight_start, daylight_bias,
|
||
|
key_name, daylight_disabled,)
|
||
|
|
||
|
def __init_from_other(self, other):
|
||
|
if not isinstance(other, TIME_ZONE_INFORMATION):
|
||
|
raise TypeError("Not a TIME_ZONE_INFORMATION")
|
||
|
for name in other.field_names():
|
||
|
# explicitly get the value from the underlying structure
|
||
|
value = super(TimeZoneDefinition, other).__getattribute__(other, name)
|
||
|
setattr(self, name, value)
|
||
|
# consider instead of the loop above just copying the memory directly
|
||
|
# size = max(ctypes.sizeof(DYNAMIC_TIME_ZONE_INFO), ctypes.sizeof(other))
|
||
|
# ctypes.memmove(ctypes.addressof(self), other, size)
|
||
|
|
||
|
def __getattribute__(self, attr):
|
||
|
value = super(TimeZoneDefinition, self).__getattribute__(attr)
|
||
|
if 'bias' in attr:
|
||
|
value = datetime.timedelta(minutes=value)
|
||
|
return value
|
||
|
|
||
|
@classmethod
|
||
|
def current(class_):
|
||
|
"Windows Platform SDK GetTimeZoneInformation"
|
||
|
code, tzi = win32api.GetTimeZoneInformation(True)
|
||
|
return code, class_(*tzi)
|
||
|
|
||
|
def set(self):
|
||
|
tzi = tuple(getattr(self, n) for n, t in self._fields_)
|
||
|
win32api.SetTimeZoneInformation(tzi)
|
||
|
|
||
|
def copy(self):
|
||
|
# XXX - this is no longer a copy!
|
||
|
return self.__class__(self)
|
||
|
|
||
|
def locate_daylight_start(self, year):
|
||
|
return self._locate_day(year, self.daylight_start)
|
||
|
|
||
|
def locate_standard_start(self, year):
|
||
|
return self._locate_day(year, self.standard_start)
|
||
|
|
||
|
@staticmethod
|
||
|
def _locate_day(year, cutoff):
|
||
|
"""
|
||
|
Takes a SYSTEMTIME object, such as retrieved from a TIME_ZONE_INFORMATION
|
||
|
structure or call to GetTimeZoneInformation and interprets it based on the given
|
||
|
year to identify the actual day.
|
||
|
|
||
|
This method is necessary because the SYSTEMTIME structure refers to a day by its
|
||
|
day of the week and week of the month (e.g. 4th saturday in March).
|
||
|
|
||
|
>>> SATURDAY = 6
|
||
|
>>> MARCH = 3
|
||
|
>>> st = SYSTEMTIME(2000, MARCH, SATURDAY, 4, 0, 0, 0, 0)
|
||
|
|
||
|
# according to my calendar, the 4th Saturday in March in 2009 was the 28th
|
||
|
>>> expected_date = datetime.datetime(2009, 3, 28)
|
||
|
>>> TimeZoneDefinition._locate_day(2009, st) == expected_date
|
||
|
True
|
||
|
"""
|
||
|
# MS stores Sunday as 0, Python datetime stores Monday as zero
|
||
|
target_weekday = (cutoff.day_of_week + 6) % 7
|
||
|
# For SYSTEMTIMEs relating to time zone inforamtion, cutoff.day
|
||
|
# is the week of the month
|
||
|
week_of_month = cutoff.day
|
||
|
# so the following is the first day of that week
|
||
|
day = (week_of_month - 1) * 7 + 1
|
||
|
result = datetime.datetime(
|
||
|
year, cutoff.month, day,
|
||
|
cutoff.hour, cutoff.minute, cutoff.second, cutoff.millisecond)
|
||
|
# now the result is the correct week, but not necessarily the correct day of the week
|
||
|
days_to_go = (target_weekday - result.weekday()) % 7
|
||
|
result += datetime.timedelta(days_to_go)
|
||
|
# if we selected a day in the month following the target month,
|
||
|
# move back a week or two.
|
||
|
# This is necessary because Microsoft defines the fifth week in a month
|
||
|
# to be the last week in a month and adding the time delta might have
|
||
|
# pushed the result into the next month.
|
||
|
while result.month == cutoff.month + 1:
|
||
|
result -= datetime.timedelta(weeks = 1)
|
||
|
return result
|
||
|
|
||
|
|
||
|
class TimeZoneInfo(datetime.tzinfo):
|
||
|
"""
|
||
|
Main class for handling Windows time zones.
|
||
|
Usage:
|
||
|
TimeZoneInfo(<Time Zone Standard Name>, [<Fix Standard Time>])
|
||
|
|
||
|
If <Fix Standard Time> evaluates to True, daylight savings time is
|
||
|
calculated in the same way as standard time.
|
||
|
|
||
|
>>> tzi = TimeZoneInfo('Pacific Standard Time')
|
||
|
>>> march31 = datetime.datetime(2000,3,31)
|
||
|
|
||
|
We know that time zone definitions haven't changed from 2007
|
||
|
to 2012, so regardless of whether dynamic info is available,
|
||
|
there should be consistent results for these years.
|
||
|
>>> subsequent_years = [march31.replace(year=year)
|
||
|
... for year in range(2007, 2013)]
|
||
|
>>> offsets = set(tzi.utcoffset(year) for year in subsequent_years)
|
||
|
>>> len(offsets)
|
||
|
1
|
||
|
"""
|
||
|
|
||
|
# this key works for WinNT+, but not for the Win95 line.
|
||
|
tzRegKey = r'SOFTWARE\Microsoft\Windows NT\CurrentVersion\Time Zones'
|
||
|
|
||
|
def __init__(self, param=None, fix_standard_time=False):
|
||
|
if isinstance(param, TimeZoneDefinition):
|
||
|
self._LoadFromTZI(param)
|
||
|
if isinstance(param, str):
|
||
|
self.timeZoneName = param
|
||
|
self._LoadInfoFromKey()
|
||
|
self.fixedStandardTime = fix_standard_time
|
||
|
|
||
|
def _FindTimeZoneKey(self):
|
||
|
"""Find the registry key for the time zone name (self.timeZoneName)."""
|
||
|
# for multi-language compatability, match the time zone name in the
|
||
|
# "Std" key of the time zone key.
|
||
|
zoneNames = dict(self._get_indexed_time_zone_keys('Std'))
|
||
|
# Also match the time zone key name itself, to be compatible with
|
||
|
# English-based hard-coded time zones.
|
||
|
timeZoneName = zoneNames.get(self.timeZoneName, self.timeZoneName)
|
||
|
key = _RegKeyDict.open(winreg.HKEY_LOCAL_MACHINE, self.tzRegKey)
|
||
|
try:
|
||
|
result = key.subkey(timeZoneName)
|
||
|
except Exception:
|
||
|
raise ValueError('Timezone Name %s not found.' % timeZoneName)
|
||
|
return result
|
||
|
|
||
|
def _LoadInfoFromKey(self):
|
||
|
"""Loads the information from an opened time zone registry key
|
||
|
into relevant fields of this TZI object"""
|
||
|
key = self._FindTimeZoneKey()
|
||
|
self.displayName = key['Display']
|
||
|
self.standardName = key['Std']
|
||
|
self.daylightName = key['Dlt']
|
||
|
self.staticInfo = TimeZoneDefinition(key['TZI'])
|
||
|
self._LoadDynamicInfoFromKey(key)
|
||
|
|
||
|
def _LoadFromTZI(self, tzi):
|
||
|
self.timeZoneName = tzi.standard_name
|
||
|
self.displayName = 'Unknown'
|
||
|
self.standardName = tzi.standard_name
|
||
|
self.daylightName = tzi.daylight_name
|
||
|
self.staticInfo = tzi
|
||
|
|
||
|
def _LoadDynamicInfoFromKey(self, key):
|
||
|
"""
|
||
|
>>> tzi = TimeZoneInfo('Central Standard Time')
|
||
|
|
||
|
Here's how the RangeMap is supposed to work:
|
||
|
>>> m = RangeMap(zip([2006,2007], 'BC'),
|
||
|
... sort_params = dict(reverse=True),
|
||
|
... key_match_comparator=operator.ge)
|
||
|
>>> m.get(2000, 'A')
|
||
|
'A'
|
||
|
>>> m[2006]
|
||
|
'B'
|
||
|
>>> m[2007]
|
||
|
'C'
|
||
|
>>> m[2008]
|
||
|
'C'
|
||
|
|
||
|
>>> m[RangeMap.last_item]
|
||
|
'B'
|
||
|
|
||
|
>>> m.get(2008, m[RangeMap.last_item])
|
||
|
'C'
|
||
|
|
||
|
|
||
|
Now test the dynamic info (but fallback to our simple RangeMap
|
||
|
on systems that don't have dynamicInfo).
|
||
|
|
||
|
>>> dinfo = getattr(tzi, 'dynamicInfo', m)
|
||
|
>>> 2007 in dinfo
|
||
|
True
|
||
|
>>> 2008 in dinfo
|
||
|
False
|
||
|
>>> dinfo[2007] == dinfo[2008] == dinfo[2012]
|
||
|
True
|
||
|
"""
|
||
|
try:
|
||
|
info = key.subkey('Dynamic DST')
|
||
|
except WindowsError:
|
||
|
return
|
||
|
del info['FirstEntry']
|
||
|
del info['LastEntry']
|
||
|
years = map(int, list(info.keys()))
|
||
|
values = map(TimeZoneDefinition, list(info.values()))
|
||
|
# create a range mapping that searches by descending year and matches
|
||
|
# if the target year is greater or equal.
|
||
|
self.dynamicInfo = RangeMap(
|
||
|
zip(years, values),
|
||
|
sort_params=dict(reverse=True),
|
||
|
key_match_comparator=operator.ge)
|
||
|
|
||
|
def __repr__(self):
|
||
|
result = '%s(%s' % (self.__class__.__name__, repr(self.timeZoneName))
|
||
|
if self.fixedStandardTime:
|
||
|
result += ', True'
|
||
|
result += ')'
|
||
|
return result
|
||
|
|
||
|
def __str__(self):
|
||
|
return self.displayName
|
||
|
|
||
|
def tzname(self, dt):
|
||
|
winInfo = self.getWinInfo(dt)
|
||
|
if self.dst(dt) == winInfo.daylight_bias:
|
||
|
result = self.daylightName
|
||
|
elif self.dst(dt) == winInfo.standard_bias:
|
||
|
result = self.standardName
|
||
|
return result
|
||
|
|
||
|
def getWinInfo(self, targetYear):
|
||
|
"""
|
||
|
Return the most relevant "info" for this time zone
|
||
|
in the target year.
|
||
|
"""
|
||
|
if not hasattr(self, 'dynamicInfo') or not self.dynamicInfo:
|
||
|
return self.staticInfo
|
||
|
# Find the greatest year entry in self.dynamicInfo which is for
|
||
|
# a year greater than or equal to our targetYear. If not found,
|
||
|
# default to the earliest year.
|
||
|
return self.dynamicInfo.get(
|
||
|
targetYear, self.dynamicInfo[RangeMap.last_item])
|
||
|
|
||
|
def _getStandardBias(self, dt):
|
||
|
winInfo = self.getWinInfo(dt.year)
|
||
|
return winInfo.bias + winInfo.standard_bias
|
||
|
|
||
|
def _getDaylightBias(self, dt):
|
||
|
winInfo = self.getWinInfo(dt.year)
|
||
|
return winInfo.bias + winInfo.daylight_bias
|
||
|
|
||
|
def utcoffset(self, dt):
|
||
|
"Calculates the utcoffset according to the datetime.tzinfo spec"
|
||
|
if dt is None:
|
||
|
return
|
||
|
winInfo = self.getWinInfo(dt.year)
|
||
|
return -winInfo.bias + self.dst(dt)
|
||
|
|
||
|
def dst(self, dt):
|
||
|
"""
|
||
|
Calculate the daylight savings offset according to the
|
||
|
datetime.tzinfo spec.
|
||
|
"""
|
||
|
if dt is None:
|
||
|
return
|
||
|
winInfo = self.getWinInfo(dt.year)
|
||
|
if not self.fixedStandardTime and self._inDaylightSavings(dt):
|
||
|
result = winInfo.daylight_bias
|
||
|
else:
|
||
|
result = winInfo.standard_bias
|
||
|
return -result
|
||
|
|
||
|
def _inDaylightSavings(self, dt):
|
||
|
dt = dt.replace(tzinfo=None)
|
||
|
winInfo = self.getWinInfo(dt.year)
|
||
|
try:
|
||
|
dstStart = self.GetDSTStartTime(dt.year)
|
||
|
dstEnd = self.GetDSTEndTime(dt.year)
|
||
|
|
||
|
# at the end of DST, when clocks are moved back, there's a period
|
||
|
# of daylight_bias where it's ambiguous whether we're in DST or
|
||
|
# not.
|
||
|
dstEndAdj = dstEnd + winInfo.daylight_bias
|
||
|
|
||
|
# the same thing could theoretically happen at the start of DST
|
||
|
# if there's a standard_bias (which I suspect is always 0).
|
||
|
dstStartAdj = dstStart + winInfo.standard_bias
|
||
|
|
||
|
if dstStart < dstEnd:
|
||
|
in_dst = dstStartAdj <= dt < dstEndAdj
|
||
|
else:
|
||
|
# in the southern hemisphere, daylight savings time
|
||
|
# typically ends before it begins in a given year.
|
||
|
in_dst = not (dstEndAdj < dt <= dstStartAdj)
|
||
|
except ValueError:
|
||
|
# there was an error parsing the time zone, which is normal when a
|
||
|
# start and end time are not specified.
|
||
|
in_dst = False
|
||
|
|
||
|
return in_dst
|
||
|
|
||
|
def GetDSTStartTime(self, year):
|
||
|
"Given a year, determines the time when daylight savings time starts"
|
||
|
return self.getWinInfo(year).locate_daylight_start(year)
|
||
|
|
||
|
def GetDSTEndTime(self, year):
|
||
|
"Given a year, determines the time when daylight savings ends."
|
||
|
return self.getWinInfo(year).locate_standard_start(year)
|
||
|
|
||
|
def __cmp__(self, other):
|
||
|
return cmp(self.__dict__, other.__dict__)
|
||
|
|
||
|
def __eq__(self, other):
|
||
|
return self.__dict__ == other.__dict__
|
||
|
|
||
|
def __ne__(self, other):
|
||
|
return self.__dict__ != other.__dict__
|
||
|
|
||
|
@classmethod
|
||
|
def local(class_):
|
||
|
"""Returns the local time zone as defined by the operating system in the
|
||
|
registry.
|
||
|
>>> localTZ = TimeZoneInfo.local()
|
||
|
>>> now_local = datetime.datetime.now(localTZ)
|
||
|
>>> now_UTC = datetime.datetime.utcnow()
|
||
|
>>> (now_UTC - now_local) < datetime.timedelta(seconds = 5)
|
||
|
Traceback (most recent call last):
|
||
|
...
|
||
|
TypeError: can't subtract offset-naive and offset-aware datetimes
|
||
|
|
||
|
>>> now_UTC = now_UTC.replace(tzinfo = TimeZoneInfo('GMT Standard Time', True))
|
||
|
|
||
|
Now one can compare the results of the two offset aware values
|
||
|
>>> (now_UTC - now_local) < datetime.timedelta(seconds = 5)
|
||
|
True
|
||
|
"""
|
||
|
code, info = TimeZoneDefinition.current()
|
||
|
# code is 0 if daylight savings is disabled or not defined
|
||
|
# code is 1 or 2 if daylight savings is enabled, 2 if currently active
|
||
|
fix_standard_time = not code
|
||
|
# note that although the given information is sufficient
|
||
|
# to construct a WinTZI object, it's
|
||
|
# not sufficient to represent the time zone in which
|
||
|
# the current user is operating due
|
||
|
# to dynamic time zones.
|
||
|
return class_(info, fix_standard_time)
|
||
|
|
||
|
@classmethod
|
||
|
def utc(class_):
|
||
|
"""Returns a time-zone representing UTC.
|
||
|
|
||
|
Same as TimeZoneInfo('GMT Standard Time', True) but caches the result
|
||
|
for performance.
|
||
|
|
||
|
>>> isinstance(TimeZoneInfo.utc(), TimeZoneInfo)
|
||
|
True
|
||
|
"""
|
||
|
if '_tzutc' not in class_.__dict__:
|
||
|
setattr(class_, '_tzutc', class_('GMT Standard Time', True))
|
||
|
return class_._tzutc
|
||
|
|
||
|
# helper methods for accessing the timezone info from the registry
|
||
|
@staticmethod
|
||
|
def _get_time_zone_key(subkey=None):
|
||
|
"Return the registry key that stores time zone details"
|
||
|
key = _RegKeyDict.open(
|
||
|
winreg.HKEY_LOCAL_MACHINE, TimeZoneInfo.tzRegKey)
|
||
|
if subkey:
|
||
|
key = key.subkey(subkey)
|
||
|
return key
|
||
|
|
||
|
@staticmethod
|
||
|
def _get_time_zone_key_names():
|
||
|
"Returns the names of the (registry keys of the) time zones"
|
||
|
return TimeZoneInfo._get_time_zone_key().subkeys()
|
||
|
|
||
|
@staticmethod
|
||
|
def _get_indexed_time_zone_keys(index_key='Index'):
|
||
|
"""
|
||
|
Get the names of the registry keys indexed by a value in that key,
|
||
|
ignoring any keys for which that value is empty or missing.
|
||
|
"""
|
||
|
key_names = list(TimeZoneInfo._get_time_zone_key_names())
|
||
|
|
||
|
def get_index_value(key_name):
|
||
|
key = TimeZoneInfo._get_time_zone_key(key_name)
|
||
|
return key.get(index_key)
|
||
|
|
||
|
values = map(get_index_value, key_names)
|
||
|
|
||
|
return (
|
||
|
(value, key_name)
|
||
|
for value, key_name in zip(values, key_names)
|
||
|
if value
|
||
|
)
|
||
|
|
||
|
@staticmethod
|
||
|
def get_sorted_time_zone_names():
|
||
|
"""
|
||
|
Return a list of time zone names that can
|
||
|
be used to initialize TimeZoneInfo instances.
|
||
|
"""
|
||
|
tzs = TimeZoneInfo.get_sorted_time_zones()
|
||
|
return [tz.standardName for tz in tzs]
|
||
|
|
||
|
@staticmethod
|
||
|
def get_all_time_zones():
|
||
|
return [
|
||
|
TimeZoneInfo(n) for n in TimeZoneInfo._get_time_zone_key_names()]
|
||
|
|
||
|
@staticmethod
|
||
|
def get_sorted_time_zones(key=None):
|
||
|
"""
|
||
|
Return the time zones sorted by some key.
|
||
|
key must be a function that takes a TimeZoneInfo object and returns
|
||
|
a value suitable for sorting on.
|
||
|
The key defaults to the bias (descending), as is done in Windows
|
||
|
(see http://blogs.msdn.com/michkap/archive/2006/12/22/1350684.aspx)
|
||
|
"""
|
||
|
key = key or (lambda tzi: -tzi.staticInfo.bias)
|
||
|
zones = TimeZoneInfo.get_all_time_zones()
|
||
|
zones.sort(key=key)
|
||
|
return zones
|
||
|
|
||
|
|
||
|
class _RegKeyDict(dict):
|
||
|
def __init__(self, key):
|
||
|
dict.__init__(self)
|
||
|
self.key = key
|
||
|
self.__load_values()
|
||
|
|
||
|
@classmethod
|
||
|
def open(cls, *args, **kargs):
|
||
|
return _RegKeyDict(winreg.OpenKeyEx(*args, **kargs))
|
||
|
|
||
|
def subkey(self, name):
|
||
|
return _RegKeyDict(winreg.OpenKeyEx(self.key, name))
|
||
|
|
||
|
def __load_values(self):
|
||
|
pairs = [(n, v) for (n, v, t) in self._enumerate_reg_values(self.key)]
|
||
|
self.update(pairs)
|
||
|
|
||
|
def subkeys(self):
|
||
|
return self._enumerate_reg_keys(self.key)
|
||
|
|
||
|
@staticmethod
|
||
|
def _enumerate_reg_values(key):
|
||
|
return _RegKeyDict._enumerate_reg(key, winreg.EnumValue)
|
||
|
|
||
|
@staticmethod
|
||
|
def _enumerate_reg_keys(key):
|
||
|
return _RegKeyDict._enumerate_reg(key, winreg.EnumKey)
|
||
|
|
||
|
@staticmethod
|
||
|
def _enumerate_reg(key, func):
|
||
|
"Enumerates an open registry key as an iterable generator"
|
||
|
try:
|
||
|
for index in count():
|
||
|
yield func(key, index)
|
||
|
except WindowsError:
|
||
|
pass
|
||
|
|
||
|
|
||
|
def utcnow():
|
||
|
"""
|
||
|
Return the UTC time now with timezone awareness as enabled
|
||
|
by this module
|
||
|
>>> now = utcnow()
|
||
|
"""
|
||
|
now = datetime.datetime.utcnow()
|
||
|
now = now.replace(tzinfo=TimeZoneInfo.utc())
|
||
|
return now
|
||
|
|
||
|
|
||
|
def now():
|
||
|
"""
|
||
|
Return the local time now with timezone awareness as enabled
|
||
|
by this module
|
||
|
>>> now_local = now()
|
||
|
"""
|
||
|
return datetime.datetime.now(TimeZoneInfo.local())
|
||
|
|
||
|
|
||
|
def GetTZCapabilities():
|
||
|
"""
|
||
|
Run a few known tests to determine the capabilities of
|
||
|
the time zone database on this machine.
|
||
|
Note Dynamic Time Zone support is not available on any
|
||
|
platform at this time; this
|
||
|
is a limitation of this library, not the platform."""
|
||
|
tzi = TimeZoneInfo('Mountain Standard Time')
|
||
|
MissingTZPatch = (
|
||
|
datetime.datetime(2007, 11, 2, tzinfo=tzi).utctimetuple()
|
||
|
!= (2007, 11, 2, 6, 0, 0, 4, 306, 0)
|
||
|
)
|
||
|
DynamicTZSupport = (
|
||
|
not MissingTZPatch
|
||
|
and datetime.datetime(2003, 11, 2, tzinfo=tzi).utctimetuple()
|
||
|
== (2003, 11, 2, 7, 0, 0, 6, 306, 0)
|
||
|
)
|
||
|
del tzi
|
||
|
return locals()
|
||
|
|
||
|
|
||
|
class DLLHandleCache(object):
|
||
|
def __init__(self):
|
||
|
self.__cache = {}
|
||
|
|
||
|
def __getitem__(self, filename):
|
||
|
key = filename.lower()
|
||
|
return self.__cache.setdefault(key, win32api.LoadLibrary(key))
|
||
|
|
||
|
|
||
|
DLLCache = DLLHandleCache()
|
||
|
|
||
|
|
||
|
def resolveMUITimeZone(spec):
|
||
|
"""Resolve a multilingual user interface resource for the time zone name
|
||
|
>>> #some pre-amble for the doc-tests to be py2k and py3k aware)
|
||
|
>>> try: unicode and None
|
||
|
... except NameError: unicode=str
|
||
|
...
|
||
|
>>> import sys
|
||
|
>>> result = resolveMUITimeZone('@tzres.dll,-110')
|
||
|
>>> expectedResultType = [type(None),unicode][sys.getwindowsversion() >= (6,)]
|
||
|
>>> type(result) is expectedResultType
|
||
|
True
|
||
|
|
||
|
spec should be of the format @path,-stringID[;comment]
|
||
|
see http://msdn2.microsoft.com/en-us/library/ms725481.aspx for details
|
||
|
"""
|
||
|
pattern = re.compile(
|
||
|
r'@(?P<dllname>.*),-(?P<index>\d+)(?:;(?P<comment>.*))?')
|
||
|
matcher = pattern.match(spec)
|
||
|
assert matcher, 'Could not parse MUI spec'
|
||
|
|
||
|
try:
|
||
|
handle = DLLCache[matcher.groupdict()['dllname']]
|
||
|
result = win32api.LoadString(handle, int(matcher.groupdict()['index']))
|
||
|
except win32api.error:
|
||
|
result = None
|
||
|
return result
|
||
|
|
||
|
|
||
|
# from jaraco.util.dictlib 5.3.1
|
||
|
class RangeMap(dict):
|
||
|
"""
|
||
|
A dictionary-like object that uses the keys as bounds for a range.
|
||
|
Inclusion of the value for that range is determined by the
|
||
|
key_match_comparator, which defaults to less-than-or-equal.
|
||
|
A value is returned for a key if it is the first key that matches in
|
||
|
the sorted list of keys.
|
||
|
|
||
|
One may supply keyword parameters to be passed to the sort function used
|
||
|
to sort keys (i.e. cmp [python 2 only], keys, reverse) as sort_params.
|
||
|
|
||
|
Let's create a map that maps 1-3 -> 'a', 4-6 -> 'b'
|
||
|
>>> r = RangeMap({3: 'a', 6: 'b'}) # boy, that was easy
|
||
|
>>> r[1], r[2], r[3], r[4], r[5], r[6]
|
||
|
('a', 'a', 'a', 'b', 'b', 'b')
|
||
|
|
||
|
Even float values should work so long as the comparison operator
|
||
|
supports it.
|
||
|
>>> r[4.5]
|
||
|
'b'
|
||
|
|
||
|
But you'll notice that the way rangemap is defined, it must be open-ended on one side.
|
||
|
>>> r[0]
|
||
|
'a'
|
||
|
>>> r[-1]
|
||
|
'a'
|
||
|
|
||
|
One can close the open-end of the RangeMap by using undefined_value
|
||
|
>>> r = RangeMap({0: RangeMap.undefined_value, 3: 'a', 6: 'b'})
|
||
|
>>> r[0]
|
||
|
Traceback (most recent call last):
|
||
|
...
|
||
|
KeyError: 0
|
||
|
|
||
|
One can get the first or last elements in the range by using RangeMap.Item
|
||
|
>>> last_item = RangeMap.Item(-1)
|
||
|
>>> r[last_item]
|
||
|
'b'
|
||
|
|
||
|
.last_item is a shortcut for Item(-1)
|
||
|
>>> r[RangeMap.last_item]
|
||
|
'b'
|
||
|
|
||
|
Sometimes it's useful to find the bounds for a RangeMap
|
||
|
>>> r.bounds()
|
||
|
(0, 6)
|
||
|
|
||
|
RangeMap supports .get(key, default)
|
||
|
>>> r.get(0, 'not found')
|
||
|
'not found'
|
||
|
|
||
|
>>> r.get(7, 'not found')
|
||
|
'not found'
|
||
|
|
||
|
"""
|
||
|
def __init__(
|
||
|
self, source, sort_params={}, key_match_comparator=operator.le):
|
||
|
dict.__init__(self, source)
|
||
|
self.sort_params = sort_params
|
||
|
self.match = key_match_comparator
|
||
|
|
||
|
def __getitem__(self, item):
|
||
|
sorted_keys = sorted(list(self.keys()), **self.sort_params)
|
||
|
if isinstance(item, RangeMap.Item):
|
||
|
result = self.__getitem__(sorted_keys[item])
|
||
|
else:
|
||
|
key = self._find_first_match_(sorted_keys, item)
|
||
|
result = dict.__getitem__(self, key)
|
||
|
if result is RangeMap.undefined_value:
|
||
|
raise KeyError(key)
|
||
|
return result
|
||
|
|
||
|
def get(self, key, default=None):
|
||
|
"""
|
||
|
Return the value for key if key is in the dictionary, else default.
|
||
|
If default is not given, it defaults to None, so that this method
|
||
|
never raises a KeyError.
|
||
|
"""
|
||
|
try:
|
||
|
return self[key]
|
||
|
except KeyError:
|
||
|
return default
|
||
|
|
||
|
def _find_first_match_(self, keys, item):
|
||
|
def is_match(k):
|
||
|
return self.match(item, k)
|
||
|
matches = list(filter(is_match, keys))
|
||
|
if matches:
|
||
|
return matches[0]
|
||
|
raise KeyError(item)
|
||
|
|
||
|
def bounds(self):
|
||
|
sorted_keys = sorted(list(self.keys()), **self.sort_params)
|
||
|
return (
|
||
|
sorted_keys[RangeMap.first_item],
|
||
|
sorted_keys[RangeMap.last_item],
|
||
|
)
|
||
|
|
||
|
# some special values for the RangeMap
|
||
|
undefined_value = type(str('RangeValueUndefined'), (object,), {})()
|
||
|
|
||
|
class Item(int):
|
||
|
pass
|
||
|
first_item = Item(0)
|
||
|
last_item = Item(-1)
|