Source code for pywws.TimeZone
#!/usr/bin/env python
# pywws - Python software for USB Wireless Weather Stations
# http://github.com/jim-easterbrook/pywws
# Copyright (C) 2008-13 Jim Easterbrook jim@jim-easterbrook.me.uk
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
"""Provide a couple of datetime.tzinfo() objects representing local
time and UTC.
Copied directly from the datetime module documentation."""
from datetime import tzinfo, timedelta, datetime
import time as _time
ZERO = timedelta(0)
HOUR = timedelta(hours=1)
[docs]class UTC(tzinfo):
"""UTC"""
[docs] def utcoffset(self, dt):
return ZERO
[docs] def tzname(self, dt):
return "UTC"
[docs] def dst(self, dt):
return ZERO
utc = UTC()
STDOFFSET = timedelta(seconds = -_time.timezone)
if _time.daylight:
DSTOFFSET = timedelta(seconds = -_time.altzone)
else:
DSTOFFSET = STDOFFSET
DSTDIFF = DSTOFFSET - STDOFFSET
[docs]class LocalTimezone(tzinfo):
"""Local time"""
[docs] def utcoffset(self, dt):
if self._isdst(dt):
return DSTOFFSET
else:
return STDOFFSET
[docs] def dst(self, dt):
if self._isdst(dt):
return DSTDIFF
else:
return ZERO
[docs] def tzname(self, dt):
return _time.tzname[self._isdst(dt)]
def _isdst(self, dt):
tt = (dt.year, dt.month, dt.day,
dt.hour, dt.minute, dt.second,
dt.weekday(), 0, -1)
stamp = _time.mktime(tt)
tt = _time.localtime(stamp)
return tt.tm_isdst > 0
Local = LocalTimezone()