psycopg/psycopg2
1
1
Fork 0
mirror of https://github.com/psycopg/psycopg2.git synced 2025-02-17 01:20:32 +03:00
Code Issues Packages Projects Releases Wiki Activity

Handle time zones with seconds in the UTC offset.

Browse Source 
The offset is rounded to the nearest minute.
This commit is contained in:
Daniele Varrazzo 2010-05-20 02:07:50 +01:00
parent e3d489f701
commit 305d86f38a
4 changed files with 66 additions and 54 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
ChangeLog
View File

@ -1,3 +1,8 @@
2010-05-20 Daniele Varrazzo <daniele.varrazzo@gmail.com>
* psycopg/typecast_datetime.c: Round seconds in historical timezones to
the nearest minute.
2010-05-17 Federico Di Gregorio <fog@initd.org>
* Release 2.2.1.

32
doc/src/usage.rst
View File

@ -365,6 +365,38 @@ the connection or globally: see the function
and then forget about this story.
.. index::
single: Time Zones
.. _tz-handling:
Time zones handling
^^^^^^^^^^^^^^^^^^^
The PostgreSQL type :sql:`timestamp with time zone` is converted into Python
`!datetime` objects with a `!tzinfo` attribute set to a
`~psycopg2.tz.FixedOffsetTimezone` instance.
>>> cur.execute("SET TIME ZONE 'Europe/Rome';") # UTC + 1 hour
>>> cur.execute("SELECT '2010-01-01 10:30:45'::timestamptz;")
>>> cur.fetchone()[0].tzinfo
psycopg2.tz.FixedOffsetTimezone(offset=60, name=None)
Notice that only time zones with an integer number of minutes are supported:
this is a limitation of the Python `!datetime` module. A few historical time
zones had seconds in the UTC offset: these time zones will have the offset
rounded to the nearest minute, with an error of up to 30 seconds.
>>> cur.execute("SET TIME ZONE 'Asia/Calcutta';") # offset was +5:53:20
>>> cur.execute("SELECT '1930-01-01 10:30:45'::timestamptz;")
>>> cur.fetchone()[0].tzinfo
psycopg2.tz.FixedOffsetTimezone(offset=353, name=None)
.. versionchanged:: 2.2.2
timezones with seconds are supported (with rounding). Previously such
timezones raised an error. In order to deal with them in previous
versions use `psycopg2.extras.register_tstz_w_secs`.
.. index:: Transaction, Begin, Commit, Rollback, Autocommit

27
psycopg/typecast_datetime.c
View File

@ -134,15 +134,11 @@ typecast_PYDATETIME_cast(const char *str, Py_ssize_t len, PyObject *curs)
Dprintf("typecast_PYDATETIME_cast: UTC offset = %ds", tz);
/* The datetime module requires that time zone offsets be
a whole number of minutes, so fail if we have a time
zone with a seconds offset.
*/
if (tz % 60 != 0) {
PyErr_Format(PyExc_ValueError, "time zone offset %d is not "
"a whole number of minutes", tz);
return NULL;
}
tzinfo = PyObject_CallFunction(tzinfo_factory, "i", tz / 60);
a whole number of minutes, so truncate the seconds to the
closest minute. */
// printf("%d %d %d\n", tz, tzmin, round(tz / 60.0));
tzinfo = PyObject_CallFunction(tzinfo_factory, "i",
(int)round(tz / 60.0));
} else {
Py_INCREF(Py_None);
tzinfo = Py_None;
@ -192,15 +188,10 @@ typecast_PYTIME_cast(const char *str, Py_ssize_t len, PyObject *curs)
Dprintf("typecast_PYTIME_cast: UTC offset = %ds", tz);
/* The datetime module requires that time zone offsets be
a whole number of minutes, so fail if we have a time
zone with a seconds offset.
*/
if (tz % 60 != 0) {
PyErr_Format(PyExc_ValueError, "time zone offset %d is not "
"a whole number of minutes", tz);
return NULL;
}
tzinfo = PyObject_CallFunction(tzinfo_factory, "i", tz / 60);
a whole number of minutes, so truncate the seconds to the
closest minute. */
tzinfo = PyObject_CallFunction(tzinfo_factory, "i",
(int)round(tz / 60.0));
} else {
Py_INCREF(Py_None);
tzinfo = Py_None;

56
tests/test_dates.py
View File

@ -124,24 +124,16 @@ class DatetimeTests(unittest.TestCase, CommonDatetimeTestsMixin):
self.check_time_tz("+01:15", 4500)
self.check_time_tz("-01:15", -4500)
# The Python datetime module does not support time zone
# offsets that are not a whole number of minutes, so we get an
# error here. Check that we are generating an understandable
# error message.
try:
self.check_time_tz("+01:15:42", 4542)
except ValueError, exc:
self.assertEqual(str(exc), "time zone offset 4542 is not a "
"whole number of minutes")
else:
self.fail("Expected ValueError")
try:
self.check_time_tz("-01:15:42", -4542)
except ValueError, exc:
self.assertEqual(str(exc), "time zone offset -4542 is not a "
"whole number of minutes")
else:
self.fail("Expected ValueError")
# offsets that are not a whole number of minutes.
# We round the offset to the nearest minute.
self.check_time_tz("+01:15:00", 60 * (60 + 15))
self.check_time_tz("+01:15:29", 60 * (60 + 15))
self.check_time_tz("+01:15:30", 60 * (60 + 16))
self.check_time_tz("+01:15:59", 60 * (60 + 16))
self.check_time_tz("-01:15:00", -60 * (60 + 15))
self.check_time_tz("-01:15:29", -60 * (60 + 15))
self.check_time_tz("-01:15:30", -60 * (60 + 16))
self.check_time_tz("-01:15:59", -60 * (60 + 16))
def check_datetime_tz(self, str_offset, offset):
from datetime import datetime, timedelta
@ -168,24 +160,16 @@ class DatetimeTests(unittest.TestCase, CommonDatetimeTestsMixin):
self.check_datetime_tz("+01:15", 4500)
self.check_datetime_tz("-01:15", -4500)
# The Python datetime module does not support time zone
# offsets that are not a whole number of minutes, so we get an
# error here. Check that we are generating an understandable
# error message.
try:
self.check_datetime_tz("+01:15:42", 4542)
except ValueError, exc:
self.assertEqual(str(exc), "time zone offset 4542 is not a "
"whole number of minutes")
else:
self.fail("Expected ValueError")
try:
self.check_datetime_tz("-01:15:42", -4542)
except ValueError, exc:
self.assertEqual(str(exc), "time zone offset -4542 is not a "
"whole number of minutes")
else:
self.fail("Expected ValueError")
# offsets that are not a whole number of minutes.
# We round the offset to the nearest minute.
self.check_datetime_tz("+01:15:00", 60 * (60 + 15))
self.check_datetime_tz("+01:15:29", 60 * (60 + 15))
self.check_datetime_tz("+01:15:30", 60 * (60 + 16))
self.check_datetime_tz("+01:15:59", 60 * (60 + 16))
self.check_datetime_tz("-01:15:00", -60 * (60 + 15))
self.check_datetime_tz("-01:15:29", -60 * (60 + 15))
self.check_datetime_tz("-01:15:30", -60 * (60 + 16))
self.check_datetime_tz("-01:15:59", -60 * (60 + 16))
def test_parse_time_no_timezone(self):
self.assertEqual(self.TIME("13:30:29", self.curs).tzinfo, None)