1 """tzinfo implementations for psycopg2
3 This module holds two different tzinfo implementations that can be used as
4 the 'tzinfo' argument to datetime constructors, directly passed to psycopg
5 functions or used to set the .tzinfo_factory attribute in cursors.
7 # psycopg/tz.py - tzinfo implementation
9 # Copyright (C) 2003-2004 Federico Di Gregorio <fog@debian.org>
11 # This program is free software; you can redistribute it and/or modify
12 # it under the terms of the GNU General Public License as published by the
13 # Free Software Foundation; either version 2, or (at your option) any later
16 # This program is distributed in the hope that it will be useful, but
17 # WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTIBILITY
18 # or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
25 ZERO = datetime.timedelta(0)
27 class FixedOffsetTimezone(datetime.tzinfo):
28 """Fixed offset in minutes east from UTC.
30 This is exactly the implementation found in Python 2.3.x documentation,
31 with a small change to the __init__ method to allow for pickling and a
32 default name in the form 'sHH:MM' ('s' is the sign.)
37 def __init__(self, offset=None, name=None):
38 if offset is not None:
39 self._offset = datetime.timedelta(minutes = offset)
43 def utcoffset(self, dt):
47 if self._name is not None:
50 seconds = self._offset.seconds + self._offset.days * 86400
51 hours, seconds = divmod(seconds, 3600)
54 return "%+03d:%d" % (hours, minutes)
56 return "%+03d" % hours
62 STDOFFSET = datetime.timedelta(seconds = -time.timezone)
64 DSTOFFSET = datetime.timedelta(seconds = -time.altzone)
67 DSTDIFF = DSTOFFSET - STDOFFSET
69 class LocalTimezone(datetime.tzinfo):
70 """Platform idea of local timezone.
72 This is the exact implementation from the Pyhton 2.3 documentation.
75 def utcoffset(self, dt):
88 return time.tzname[self._isdst(dt)]
91 tt = (dt.year, dt.month, dt.day,
92 dt.hour, dt.minute, dt.second,
94 stamp = time.mktime(tt)
95 tt = time.localtime(stamp)
96 return tt.tm_isdst > 0
98 LOCAL = LocalTimezone()
100 # TODO: pre-generate some interesting time zones?