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Diffstat (limited to 'lib/python2.7/site-packages/django/utils/timezone.py')
| -rw-r--r-- | lib/python2.7/site-packages/django/utils/timezone.py | 317 |
1 files changed, 0 insertions, 317 deletions
diff --git a/lib/python2.7/site-packages/django/utils/timezone.py b/lib/python2.7/site-packages/django/utils/timezone.py deleted file mode 100644 index 73749cf..0000000 --- a/lib/python2.7/site-packages/django/utils/timezone.py +++ /dev/null @@ -1,317 +0,0 @@ -""" -Timezone-related classes and functions. - -This module uses pytz when it's available and fallbacks when it isn't. -""" - -from datetime import datetime, timedelta, tzinfo -from threading import local -import sys -import time as _time - -try: - import pytz -except ImportError: - pytz = None - -from django.conf import settings -from django.utils import six - -__all__ = [ - 'utc', - 'get_default_timezone', 'get_default_timezone_name', - 'get_current_timezone', 'get_current_timezone_name', - 'activate', 'deactivate', 'override', - 'localtime', 'now', - 'is_aware', 'is_naive', 'make_aware', 'make_naive', -] - - -# UTC and local time zones - -ZERO = timedelta(0) - -class UTC(tzinfo): - """ - UTC implementation taken from Python's docs. - - Used only when pytz isn't available. - """ - - def __repr__(self): - return "<UTC>" - - def utcoffset(self, dt): - return ZERO - - def tzname(self, dt): - return "UTC" - - def dst(self, dt): - return ZERO - -class ReferenceLocalTimezone(tzinfo): - """ - Local time implementation taken from Python's docs. - - Used only when pytz isn't available, and most likely inaccurate. If you're - having trouble with this class, don't waste your time, just install pytz. - - Kept identical to the reference version. Subclasses contain improvements. - """ - - def __init__(self): - # This code is moved in __init__ to execute it as late as possible - # See get_default_timezone(). - self.STDOFFSET = timedelta(seconds=-_time.timezone) - if _time.daylight: - self.DSTOFFSET = timedelta(seconds=-_time.altzone) - else: - self.DSTOFFSET = self.STDOFFSET - self.DSTDIFF = self.DSTOFFSET - self.STDOFFSET - tzinfo.__init__(self) - - def __repr__(self): - return "<LocalTimezone>" - - def utcoffset(self, dt): - if self._isdst(dt): - return self.DSTOFFSET - else: - return self.STDOFFSET - - def dst(self, dt): - if self._isdst(dt): - return self.DSTDIFF - else: - return ZERO - - def tzname(self, dt): - is_dst = False if dt is None else self._isdst(dt) - return _time.tzname[is_dst] - - def _isdst(self, dt): - tt = (dt.year, dt.month, dt.day, - dt.hour, dt.minute, dt.second, - dt.weekday(), 0, 0) - stamp = _time.mktime(tt) - tt = _time.localtime(stamp) - return tt.tm_isdst > 0 - -class LocalTimezone(ReferenceLocalTimezone): - """ - Slightly improved local time implementation focusing on correctness. - - It still crashes on dates before 1970 or after 2038, but at least the - error message is helpful. - """ - - def _isdst(self, dt): - try: - return super(LocalTimezone, self)._isdst(dt) - except (OverflowError, ValueError) as exc: - exc_type = type(exc) - exc_value = exc_type( - "Unsupported value: %r. You should install pytz." % dt) - exc_value.__cause__ = exc - six.reraise(exc_type, exc_value, sys.exc_info()[2]) - -utc = pytz.utc if pytz else UTC() -"""UTC time zone as a tzinfo instance.""" - -# In order to avoid accessing the settings at compile time, -# wrap the expression in a function and cache the result. -_localtime = None - -def get_default_timezone(): - """ - Returns the default time zone as a tzinfo instance. - - This is the time zone defined by settings.TIME_ZONE. - - See also :func:`get_current_timezone`. - """ - global _localtime - if _localtime is None: - if isinstance(settings.TIME_ZONE, six.string_types) and pytz is not None: - _localtime = pytz.timezone(settings.TIME_ZONE) - else: - # This relies on os.environ['TZ'] being set to settings.TIME_ZONE. - _localtime = LocalTimezone() - return _localtime - -# This function exists for consistency with get_current_timezone_name -def get_default_timezone_name(): - """ - Returns the name of the default time zone. - """ - return _get_timezone_name(get_default_timezone()) - -_active = local() - -def get_current_timezone(): - """ - Returns the currently active time zone as a tzinfo instance. - """ - return getattr(_active, "value", get_default_timezone()) - -def get_current_timezone_name(): - """ - Returns the name of the currently active time zone. - """ - return _get_timezone_name(get_current_timezone()) - -def _get_timezone_name(timezone): - """ - Returns the name of ``timezone``. - """ - try: - # for pytz timezones - return timezone.zone - except AttributeError: - # for regular tzinfo objects - return timezone.tzname(None) - -# Timezone selection functions. - -# These functions don't change os.environ['TZ'] and call time.tzset() -# because it isn't thread safe. - -def activate(timezone): - """ - Sets the time zone for the current thread. - - The ``timezone`` argument must be an instance of a tzinfo subclass or a - time zone name. If it is a time zone name, pytz is required. - """ - if isinstance(timezone, tzinfo): - _active.value = timezone - elif isinstance(timezone, six.string_types) and pytz is not None: - _active.value = pytz.timezone(timezone) - else: - raise ValueError("Invalid timezone: %r" % timezone) - -def deactivate(): - """ - Unsets the time zone for the current thread. - - Django will then use the time zone defined by settings.TIME_ZONE. - """ - if hasattr(_active, "value"): - del _active.value - -class override(object): - """ - Temporarily set the time zone for the current thread. - - This is a context manager that uses ``~django.utils.timezone.activate()`` - to set the timezone on entry, and restores the previously active timezone - on exit. - - The ``timezone`` argument must be an instance of a ``tzinfo`` subclass, a - time zone name, or ``None``. If is it a time zone name, pytz is required. - If it is ``None``, Django enables the default time zone. - """ - def __init__(self, timezone): - self.timezone = timezone - self.old_timezone = getattr(_active, 'value', None) - - def __enter__(self): - if self.timezone is None: - deactivate() - else: - activate(self.timezone) - - def __exit__(self, exc_type, exc_value, traceback): - if self.old_timezone is None: - deactivate() - else: - _active.value = self.old_timezone - - -# Templates - -def template_localtime(value, use_tz=None): - """ - Checks if value is a datetime and converts it to local time if necessary. - - If use_tz is provided and is not None, that will force the value to - be converted (or not), overriding the value of settings.USE_TZ. - - This function is designed for use by the template engine. - """ - should_convert = (isinstance(value, datetime) - and (settings.USE_TZ if use_tz is None else use_tz) - and not is_naive(value) - and getattr(value, 'convert_to_local_time', True)) - return localtime(value) if should_convert else value - - -# Utilities - -def localtime(value, timezone=None): - """ - Converts an aware datetime.datetime to local time. - - Local time is defined by the current time zone, unless another time zone - is specified. - """ - if timezone is None: - timezone = get_current_timezone() - value = value.astimezone(timezone) - if hasattr(timezone, 'normalize'): - # available for pytz time zones - value = timezone.normalize(value) - return value - -def now(): - """ - Returns an aware or naive datetime.datetime, depending on settings.USE_TZ. - """ - if settings.USE_TZ: - # timeit shows that datetime.now(tz=utc) is 24% slower - return datetime.utcnow().replace(tzinfo=utc) - else: - return datetime.now() - -# By design, these four functions don't perform any checks on their arguments. -# The caller should ensure that they don't receive an invalid value like None. - -def is_aware(value): - """ - Determines if a given datetime.datetime is aware. - - The logic is described in Python's docs: - http://docs.python.org/library/datetime.html#datetime.tzinfo - """ - return value.tzinfo is not None and value.tzinfo.utcoffset(value) is not None - -def is_naive(value): - """ - Determines if a given datetime.datetime is naive. - - The logic is described in Python's docs: - http://docs.python.org/library/datetime.html#datetime.tzinfo - """ - return value.tzinfo is None or value.tzinfo.utcoffset(value) is None - -def make_aware(value, timezone): - """ - Makes a naive datetime.datetime in a given time zone aware. - """ - if hasattr(timezone, 'localize'): - # available for pytz time zones - return timezone.localize(value, is_dst=None) - else: - # may be wrong around DST changes - return value.replace(tzinfo=timezone) - -def make_naive(value, timezone): - """ - Makes an aware datetime.datetime naive in a given time zone. - """ - value = value.astimezone(timezone) - if hasattr(timezone, 'normalize'): - # available for pytz time zones - value = timezone.normalize(value) - return value.replace(tzinfo=None) |