Convert rruleset to json and back

rruleset_json.py

# rruleset_json.py by Max 2022

# To the extent possible under law, the person who associated CC0 with
# rruleset_json.py has waived all copyright and related or neighboring rights
# to rruleset_json.py.

# You should have received a copy of the CC0 legalcode along with this
# work.  If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.

# https://gist.github.com/maxfire2008/096fd5f55c9d79a11d41769d58e8bca1

import json
import dateutil.rrule
import datetime


def rruleset_to_json(rruleset):
    """
    Convert a rruleset to a JSON string.
    """
    return json.dumps({
        'rrule': [str(rrule) for rrule in rruleset._rrule],
        'rdate': [rdate.isoformat() for rdate in rruleset._rdate],
        'exrule': [str(exrule) for exrule in rruleset._exrule],
        'exdate': [exdate.isoformat() for exdate in rruleset._exdate],
    })


def json_to_rruleset(json_string):
    """
    Convert a JSON string to a rruleset.
    """
    if type(json_string) == str:
        data = json.loads(json_string)
    else:
        data = json_string
    rruleset = dateutil.rrule.rruleset()
    rruleset._rrule = [dateutil.rrule.rrulestr(
        rrule) for rrule in data['rrule']]
    rruleset._rdate = [datetime.datetime.fromisoformat(
        rdate) for rdate in data['rdate']]
    rruleset._exrule = [dateutil.rrule.rrulestr(
        exrule) for exrule in data['exrule']]
    rruleset._exdate = [datetime.datetime.fromisoformat(
        exdate) for exdate in data['exdate']]
    return rruleset


if __name__ == "__main__":
    from dateutil.rrule import *
    from dateutil.parser import *
    import datetime

    print("Daily, for 7 days, jumping Saturday and Sunday occurrences.")
    set = rruleset()
    set.rrule(rrule(DAILY, count=7, dtstart=parse("19970902T090000")))
    set.exrule(rrule(YEARLY, byweekday=(SA, SU),
               dtstart=parse("19970902T090000")))

    rrule_as_json = rruleset_to_json(set)
    converted = json_to_rruleset(rrule_as_json)

    print(rrule_as_json)
    print(set[:10])
    print(converted[:10])
    print(set[:10] == converted[:10])
    
    print("Weekly, for 4 weeks, plus one time on day 7, and not on day 16.")
    set = rruleset()
    set.rrule(rrule(WEEKLY, count=4, dtstart=parse("19970902T090000")))
    set.rdate(datetime.datetime(1997, 9, 7, 9, 0))
    set.exdate(datetime.datetime(1997, 9, 16, 9, 0))

    rrule_as_json = rruleset_to_json(set)
    converted = json_to_rruleset(rrule_as_json)

    print(rrule_as_json)
    print(set[:10])
    print(converted[:10])
    print(set[:10] == converted[:10])