This document describes the current stable version of Celery (5.6). For development docs, go here.

# Source code for celery.utils.iso8601

    """Parse ISO8601 dates.

    Originally taken from :pypi:`pyiso8601`
    (https://bitbucket.org/micktwomey/pyiso8601)

    Modified to match the behavior of ``dateutil.parser``:

        - raise :exc:`ValueError` instead of ``ParseError``
        - return naive :class:`~datetime.datetime` by default

    This is the original License:

    Copyright (c) 2007 Michael Twomey

    Permission is hereby granted, free of charge, to any person obtaining a
    copy of this software and associated documentation files (the
    "Software"), to deal in the Software without restriction, including
    without limitation the rights to use, copy, modify, merge, publish,
    distribute, sub-license, and/or sell copies of the Software, and to
    permit persons to whom the Software is furnished to do so, subject to
    the following conditions:

    The above copyright notice and this permission notice shall be included
    in all copies or substantial portions of the Software.

    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
    IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
    CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
    TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
    SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
    """
    import re
    from datetime import datetime, timedelta, timezone

    from celery.utils.deprecated import warn

    __all__ = ('parse_iso8601',)

    # Adapted from http://delete.me.uk/2005/03/iso8601.html
    ISO8601_REGEX = re.compile(
        r'(?P<year>[0-9]{4})(-(?P<month>[0-9]{1,2})(-(?P<day>[0-9]{1,2})'
        r'((?P<separator>.)(?P<hour>[0-9]{2}):(?P<minute>[0-9]{2})'
        r'(:(?P<second>[0-9]{2})(\.(?P<fraction>[0-9]+))?)?'
        r'(?P<timezone>Z|(([-+])([0-9]{2}):([0-9]{2})))?)?)?)?'
    )
    TIMEZONE_REGEX = re.compile(
        r'(?P<prefix>[+-])(?P<hours>[0-9]{2}).(?P<minutes>[0-9]{2})'
    )

    def parse_iso8601(datestring: str) -> datetime:
        """Parse and convert ISO-8601 string to datetime."""
        warn("parse_iso8601", "v5.3", "v6", "datetime.datetime.fromisoformat or dateutil.parser.isoparse")
        m = ISO8601_REGEX.match(datestring)
        if not m:
            raise ValueError('unable to parse date string %r' % datestring)
        groups = m.groupdict()
        tz = groups['timezone']
        if tz == 'Z':
            tz = timezone(timedelta(0))
        elif tz:
            m = TIMEZONE_REGEX.match(tz)
            prefix, hours, minutes = m.groups()
            hours, minutes = int(hours), int(minutes)
            if prefix == '-':
                hours = -hours
                minutes = -minutes
            tz = timezone(timedelta(minutes=minutes, hours=hours))
        return datetime(
            int(groups['year']), int(groups['month']),
            int(groups['day']), int(groups['hour'] or 0),
            int(groups['minute'] or 0), int(groups['second'] or 0),
            int(groups['fraction'] or 0), tz
        )