Source code for django.utils.tzinfo

"Implementation of tzinfo classes for use with datetime.datetime."

from __future__ import unicode_literals

from datetime import timedelta, tzinfo
import time
import warnings

from django.utils.deprecation import RemovedInDjango19Warning
from django.utils.encoding import force_str, force_text, DEFAULT_LOCALE_ENCODING

    "django.utils.tzinfo will be removed in Django 1.9. "
    "Use django.utils.timezone instead.",
    RemovedInDjango19Warning, stacklevel=2)

# Python's doc say: "A tzinfo subclass must have an __init__() method that can
# be called with no arguments". FixedOffset and LocalTimezone don't honor this
# requirement. Defining __getinitargs__ is sufficient to fix copy/deepcopy as
# well as pickling/unpickling.

[docs]class FixedOffset(tzinfo): "Fixed offset in minutes east from UTC." def __init__(self, offset): warnings.warn( "django.utils.tzinfo.FixedOffset will be removed in Django 1.9. " "Use django.utils.timezone.get_fixed_timezone instead.", RemovedInDjango19Warning) if isinstance(offset, timedelta): self.__offset = offset offset = self.__offset.seconds // 60 else: self.__offset = timedelta(minutes=offset) sign = '-' if offset < 0 else '+' self.__name = "%s%02d%02d" % (sign, abs(offset) / 60., abs(offset) % 60) def __repr__(self): return self.__name def __getinitargs__(self): return self.__offset, def utcoffset(self, dt): return self.__offset def tzname(self, dt): return self.__name def dst(self, dt): return timedelta(0) # This implementation is used for display purposes. It uses an approximation # for DST computations on dates >= 2038. # A similar implementation exists in django.utils.timezone. It's used for # timezone support (when USE_TZ = True) and focuses on correctness.
[docs]class LocalTimezone(tzinfo): "Proxy timezone information from time module." def __init__(self, dt): warnings.warn( "django.utils.tzinfo.LocalTimezone will be removed in Django 1.9. " "Use django.utils.timezone.get_default_timezone instead.", RemovedInDjango19Warning) tzinfo.__init__(self) self.__dt = dt self._tzname = self.tzname(dt) def __repr__(self): return force_str(self._tzname) def __getinitargs__(self): return self.__dt, def utcoffset(self, dt): if self._isdst(dt): return timedelta(seconds=-time.altzone) else: return timedelta(seconds=-time.timezone) def dst(self, dt): if self._isdst(dt): return timedelta(seconds=-time.altzone) - timedelta(seconds=-time.timezone) else: return timedelta(0) def tzname(self, dt): is_dst = False if dt is None else self._isdst(dt) try: return force_text(time.tzname[is_dst], DEFAULT_LOCALE_ENCODING) except UnicodeDecodeError: return None def _isdst(self, dt): tt = (dt.year, dt.month,, dt.hour, dt.minute, dt.second, dt.weekday(), 0, 0) try: stamp = time.mktime(tt) except (OverflowError, ValueError): # 32 bit systems can't handle dates after Jan 2038, and certain # systems can't handle dates before ~1901-12-01: # # >>> time.mktime((1900, 1, 13, 0, 0, 0, 0, 0, 0)) # OverflowError: mktime argument out of range # >>> time.mktime((1850, 1, 13, 0, 0, 0, 0, 0, 0)) # ValueError: year out of range # # In this case, we fake the date, because we only care about the # DST flag. tt = (2037,) + tt[1:] stamp = time.mktime(tt) tt = time.localtime(stamp) return tt.tm_isdst > 0