Handle correctly timestamps with fractions of minute in the timezone offset

Close #1272.
This commit is contained in:
Daniele Varrazzo 2021-06-14 22:24:28 +01:00
parent 5667026883
commit 476a969bd8
5 changed files with 152 additions and 79 deletions

2
NEWS
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@ -6,6 +6,8 @@ What's new in psycopg 2.9
- ``with connection`` starts a transaction on autocommit transactions too
(:ticket:`#941`).
- Timezones with fractional minutes are supported on Python 3.7 and following
(:ticket:`#1272`).
- Escape table and column names in `~cursor.copy_from()` and
`~cursor.copy_to()`.
- Connection exceptions with sqlstate ``08XXX`` reclassified as

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@ -580,25 +580,33 @@ The PostgreSQL type :sql:`timestamp with time zone` (a.k.a.
a `~datetime.datetime.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.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)
Note 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.
.. note::
>>> cur.execute("SET TIME ZONE 'Asia/Calcutta';") # offset was +5:53:20
>>> cur.execute("SELECT '1930-01-01 10:30:45'::timestamptz;")
Before Python 3.7, the `datetime` module only supported timezones with an
integer number of minutes. 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, on Python versions before 3.7.
>>> cur.execute("SET TIME ZONE 'Asia/Calcutta'") # offset was +5:21:10
>>> cur.execute("SELECT '1900-01-01 10:30:45'::timestamptz")
>>> cur.fetchone()[0].tzinfo
psycopg2.tz.FixedOffsetTimezone(offset=353, name=None)
# On Python 3.6: 5h, 21m
psycopg2.tz.FixedOffsetTimezone(offset=datetime.timedelta(0, 19260), name=None)
# On Python 3.7 and following: 5h, 21m, 10s
psycopg2.tz.FixedOffsetTimezone(offset=datetime.timedelta(seconds=19270), name=None)
.. versionchanged:: 2.2.2
timezones with seconds are supported (with rounding). Previously such
timezones raised an error.
.. versionchanged:: 2.9
timezones with seconds are supported without rounding.
.. index::
double: Date objects; Infinite

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@ -45,6 +45,11 @@ class FixedOffsetTimezone(datetime.tzinfo):
offset and name that instance will be returned. This saves memory and
improves comparability.
.. versionchanged:: 2.9
The constructor can take either a timedelta or a number of minutes of
offset. Previously only minutes were supported.
.. __: https://docs.python.org/library/datetime.html
"""
_name = None
@ -54,7 +59,9 @@ class FixedOffsetTimezone(datetime.tzinfo):
def __init__(self, offset=None, name=None):
if offset is not None:
self._offset = datetime.timedelta(minutes=offset)
if not isinstance(offset, datetime.timedelta):
offset = datetime.timedelta(minutes=offset)
self._offset = offset
if name is not None:
self._name = name
@ -70,13 +77,23 @@ class FixedOffsetTimezone(datetime.tzinfo):
return tz
def __repr__(self):
offset_mins = self._offset.seconds // 60 + self._offset.days * 24 * 60
return "psycopg2.tz.FixedOffsetTimezone(offset=%r, name=%r)" \
% (offset_mins, self._name)
% (self._offset, self._name)
def __eq__(self, other):
if isinstance(other, FixedOffsetTimezone):
return self._offset == other._offset
else:
return NotImplemented
def __ne__(self, other):
if isinstance(other, FixedOffsetTimezone):
return self._offset != other._offset
else:
return NotImplemented
def __getinitargs__(self):
offset_mins = self._offset.seconds // 60 + self._offset.days * 24 * 60
return offset_mins, self._name
return self._offset, self._name
def utcoffset(self, dt):
return self._offset
@ -84,14 +101,16 @@ class FixedOffsetTimezone(datetime.tzinfo):
def tzname(self, dt):
if self._name is not None:
return self._name
else:
seconds = self._offset.seconds + self._offset.days * 86400
hours, seconds = divmod(seconds, 3600)
minutes = seconds / 60
if minutes:
return "%+03d:%d" % (hours, minutes)
else:
return "%+03d" % hours
minutes, seconds = divmod(self._offset.total_seconds(), 60)
hours, minutes = divmod(minutes, 60)
rv = "%+03d" % hours
if minutes or seconds:
rv += ":%02d" % minutes
if seconds:
rv += ":%02d" % seconds
return rv
def dst(self, dt):
return ZERO

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@ -129,10 +129,11 @@ static PyObject *
_parse_noninftz(const char *str, Py_ssize_t len, PyObject *curs)
{
PyObject* rv = NULL;
PyObject *tzoff = NULL;
PyObject *tzinfo = NULL;
PyObject *tzinfo_factory;
int n, y=0, m=0, d=0;
int hh=0, mm=0, ss=0, us=0, tz=0;
int hh=0, mm=0, ss=0, us=0, tzsec=0;
const char *tp = NULL;
Dprintf("typecast_PYDATETIMETZ_cast: s = %s", str);
@ -147,11 +148,11 @@ _parse_noninftz(const char *str, Py_ssize_t len, PyObject *curs)
}
if (len > 0) {
n = typecast_parse_time(tp, NULL, &len, &hh, &mm, &ss, &us, &tz);
n = typecast_parse_time(tp, NULL, &len, &hh, &mm, &ss, &us, &tzsec);
Dprintf("typecast_PYDATETIMETZ_cast: n = %d,"
" len = " FORMAT_CODE_PY_SSIZE_T ","
" hh = %d, mm = %d, ss = %d, us = %d, tz = %d",
n, len, hh, mm, ss, us, tz);
" hh = %d, mm = %d, ss = %d, us = %d, tzsec = %d",
n, len, hh, mm, ss, us, tzsec);
if (n < 3 || n > 6) {
PyErr_SetString(DataError, "unable to parse time");
goto exit;
@ -169,17 +170,20 @@ _parse_noninftz(const char *str, Py_ssize_t len, PyObject *curs)
if (n >= 5 && tzinfo_factory != Py_None) {
/* we have a time zone, calculate minutes and create
appropriate tzinfo object calling the factory */
Dprintf("typecast_PYDATETIMETZ_cast: UTC offset = %ds", tz);
Dprintf("typecast_PYDATETIMETZ_cast: UTC offset = %ds", tzsec);
/* The datetime module requires that time zone offsets be
a whole number of minutes, so truncate the seconds to the
closest minute. */
// printf("%d %d %d\n", tz, tzmin, round(tz / 60.0));
if (!(tzinfo = PyObject_CallFunction(tzinfo_factory, "i",
(int)round(tz / 60.0)))) {
#if PY_VERSION_HEX < 0x03070000
/* Before Python 3.7 the timezone offset had to be a whole number
* of minutes, so round the seconds to the closest minute */
tzsec = 60 * (int)round(tzsec / 60.0);
#endif
if (!(tzoff = PyDelta_FromDSU(0, tzsec, 0))) { goto exit; }
if (!(tzinfo = PyObject_CallFunctionObjArgs(
tzinfo_factory, tzoff, NULL))) {
goto exit;
}
} else {
}
else {
Py_INCREF(Py_None);
tzinfo = Py_None;
}
@ -192,6 +196,7 @@ _parse_noninftz(const char *str, Py_ssize_t len, PyObject *curs)
y, m, d, hh, mm, ss, us, tzinfo);
exit:
Py_XDECREF(tzoff);
Py_XDECREF(tzinfo);
return rv;
}
@ -232,17 +237,18 @@ typecast_PYDATETIMETZ_cast(const char *str, Py_ssize_t len, PyObject *curs)
static PyObject *
typecast_PYTIME_cast(const char *str, Py_ssize_t len, PyObject *curs)
{
PyObject* obj = NULL;
PyObject* rv = NULL;
PyObject *tzoff = NULL;
PyObject *tzinfo = NULL;
PyObject *tzinfo_factory;
int n, hh=0, mm=0, ss=0, us=0, tz=0;
int n, hh=0, mm=0, ss=0, us=0, tzsec=0;
if (str == NULL) { Py_RETURN_NONE; }
n = typecast_parse_time(str, NULL, &len, &hh, &mm, &ss, &us, &tz);
n = typecast_parse_time(str, NULL, &len, &hh, &mm, &ss, &us, &tzsec);
Dprintf("typecast_PYTIME_cast: n = %d, len = " FORMAT_CODE_PY_SSIZE_T ", "
"hh = %d, mm = %d, ss = %d, us = %d, tz = %d",
n, len, hh, mm, ss, us, tz);
"hh = %d, mm = %d, ss = %d, us = %d, tzsec = %d",
n, len, hh, mm, ss, us, tzsec);
if (n < 3 || n > 6) {
PyErr_SetString(DataError, "unable to parse time");
@ -254,25 +260,32 @@ typecast_PYTIME_cast(const char *str, Py_ssize_t len, PyObject *curs)
}
tzinfo_factory = ((cursorObject *)curs)->tzinfo_factory;
if (n >= 5 && tzinfo_factory != Py_None) {
/* we have a time zone, calculate minutes and create
/* we have a time zone, calculate seconds and create
appropriate tzinfo object calling the factory */
Dprintf("typecast_PYTIME_cast: UTC offset = %ds", tz);
Dprintf("typecast_PYTIME_cast: UTC offset = %ds", tzsec);
/* The datetime module requires that time zone offsets be
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 {
#if PY_VERSION_HEX < 0x03070000
/* Before Python 3.7 the timezone offset had to be a whole number
* of minutes, so round the seconds to the closest minute */
tzsec = 60 * (int)round(tzsec / 60.0);
#endif
if (!(tzoff = PyDelta_FromDSU(0, tzsec, 0))) { goto exit; }
if (!(tzinfo = PyObject_CallFunctionObjArgs(tzinfo_factory, tzoff, NULL))) {
goto exit;
}
}
else {
Py_INCREF(Py_None);
tzinfo = Py_None;
}
if (tzinfo != NULL) {
obj = PyObject_CallFunction((PyObject*)PyDateTimeAPI->TimeType, "iiiiO",
rv = PyObject_CallFunction((PyObject*)PyDateTimeAPI->TimeType, "iiiiO",
hh, mm, ss, us, tzinfo);
Py_DECREF(tzinfo);
}
return obj;
exit:
Py_XDECREF(tzoff);
Py_XDECREF(tzinfo);
return rv;
}

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@ -23,6 +23,7 @@
# FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
# License for more details.
import sys
import math
import pickle
from datetime import date, datetime, time, timedelta
@ -157,7 +158,8 @@ class DatetimeTests(ConnectingTestCase, CommonDatetimeTestsMixin):
self.check_time_tz("-01", -3600)
self.check_time_tz("+01:15", 4500)
self.check_time_tz("-01:15", -4500)
# The Python datetime module does not support time zone
if sys.version_info < (3, 7):
# The Python < 3.7 datetime module does not support time zone
# 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))
@ -168,6 +170,15 @@ class DatetimeTests(ConnectingTestCase, CommonDatetimeTestsMixin):
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))
else:
self.check_time_tz("+01:15:00", 60 * (60 + 15))
self.check_time_tz("+01:15:29", 60 * (60 + 15) + 29)
self.check_time_tz("+01:15:30", 60 * (60 + 15) + 30)
self.check_time_tz("+01:15:59", 60 * (60 + 15) + 59)
self.check_time_tz("-01:15:00", -(60 * (60 + 15)))
self.check_time_tz("-01:15:29", -(60 * (60 + 15) + 29))
self.check_time_tz("-01:15:30", -(60 * (60 + 15) + 30))
self.check_time_tz("-01:15:59", -(60 * (60 + 15) + 59))
def check_datetime_tz(self, str_offset, offset):
base = datetime(2007, 1, 1, 13, 30, 29)
@ -192,7 +203,8 @@ class DatetimeTests(ConnectingTestCase, CommonDatetimeTestsMixin):
self.check_datetime_tz("-01", -3600)
self.check_datetime_tz("+01:15", 4500)
self.check_datetime_tz("-01:15", -4500)
# The Python datetime module does not support time zone
if sys.version_info < (3, 7):
# The Python < 3.7 datetime module does not support time zone
# 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))
@ -203,6 +215,15 @@ class DatetimeTests(ConnectingTestCase, CommonDatetimeTestsMixin):
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))
else:
self.check_datetime_tz("+01:15:00", 60 * (60 + 15))
self.check_datetime_tz("+01:15:29", 60 * (60 + 15) + 29)
self.check_datetime_tz("+01:15:30", 60 * (60 + 15) + 30)
self.check_datetime_tz("+01:15:59", 60 * (60 + 15) + 59)
self.check_datetime_tz("-01:15:00", -(60 * (60 + 15)))
self.check_datetime_tz("-01:15:29", -(60 * (60 + 15) + 29))
self.check_datetime_tz("-01:15:30", -(60 * (60 + 15) + 30))
self.check_datetime_tz("-01:15:59", -(60 * (60 + 15) + 59))
def test_parse_time_no_timezone(self):
self.assertEqual(self.TIME("13:30:29", self.curs).tzinfo, None)
@ -628,17 +649,27 @@ class FixedOffsetTimezoneTests(unittest.TestCase):
def test_repr_with_positive_offset(self):
tzinfo = FixedOffsetTimezone(5 * 60)
self.assertEqual(repr(tzinfo),
"psycopg2.tz.FixedOffsetTimezone(offset=300, name=None)")
"psycopg2.tz.FixedOffsetTimezone(offset=%r, name=None)"
% timedelta(minutes=5 * 60))
def test_repr_with_negative_offset(self):
tzinfo = FixedOffsetTimezone(-5 * 60)
self.assertEqual(repr(tzinfo),
"psycopg2.tz.FixedOffsetTimezone(offset=-300, name=None)")
"psycopg2.tz.FixedOffsetTimezone(offset=%r, name=None)"
% timedelta(minutes=-5 * 60))
def test_init_with_timedelta(self):
td = timedelta(minutes=5 * 60)
tzinfo = FixedOffsetTimezone(td)
self.assertEqual(tzinfo, FixedOffsetTimezone(5 * 60))
self.assertEqual(repr(tzinfo),
"psycopg2.tz.FixedOffsetTimezone(offset=%r, name=None)" % td)
def test_repr_with_name(self):
tzinfo = FixedOffsetTimezone(name="FOO")
self.assertEqual(repr(tzinfo),
"psycopg2.tz.FixedOffsetTimezone(offset=0, name='FOO')")
"psycopg2.tz.FixedOffsetTimezone(offset=%r, name='FOO')"
% timedelta(0))
def test_instance_caching(self):
self.assert_(FixedOffsetTimezone(name="FOO")