def do_crondtc(self, author, channel, serv, message):
"""Cron feature for DTC printing, max 1 minute per loop with no end
start : lanch cron for DTC, if is not
stop : cancel cron for DTC, if is start
next : print time for next cron DTC loop
update <expression> : change cron DTC frequency, if <expression> is valid"""
items = message.split()
if channel in self._cronDTC:
if message == 'start':
if self._cronDTC[channel].is_alive():
serv.privmsg(channel, 'cronDTC : already start !')
self.__prompt('host', '{%alert%}cronDTC : already start !{%default%}')
else:
serv.privmsg(channel, 'cronDTC : start !')
self.__prompt('host', '{%alert%}cronDTC : start !{%default%}')
elif message == 'stop':
if self._cronDTC[channel].is_alive():
serv.privmsg(channel, 'cronDTC : stopped !')
self.__prompt('host', '{%alert%}cronDTC : stopped !{%default%}')
else:
serv.privmsg(channel, 'cronDTC : already stopped !')
self.__prompt('host', '{%alert%}cronDTC : already stopped !{%default%}')
elif items[0] == 'update':
items.pop(0)
if len(items) > 5:
serv.privmsg(channel, 'cronDTC : update refuse ! (possible abuse frequency)')
self.__prompt('host', '{%alert%}cronDTC : update refuse ! (possible abuse frequency){%default%}')
elif croniter.is_valid(' '.join(items[:5])):
self._cronDTC[channel].expanded, self._cronDTC[channel].nth_weekday_of_month = croniter.expand(' '.join(items[:5]))
else:
serv.privmsg(channel, 'cronDTC : update refuse !')
self.__prompt('host', '{%alert%}cronDTC : update refuse !{%default%}')
elif message == 'next':
if self._cronDTC[channel].is_alive():
_next = delai(datetime.fromtimestamp(self._cronDTC[channel].get_current()))
serv.privmsg(channel, 'cronDTC : next in {next} !'.format(next = _next))
self.__prompt('host', '{%alert%}cronDTC : next in {next} !{%default%}', next = _next)
else:
return False
else:
if not message:
self._cronDTC[channel] = cron(target = self.do_dtc, expr_format = '0 * * * *', args = (self._name, channel, serv, ''))
elif croniter.is_valid(' '.join(items[:5])):
self._cronDTC[channel] = cron(target = self.do_dtc, expr_format = ' '.join(items[:5]), args = (self._name, channel, serv, ''))
else:
return False
self._cronDTC[channel].start()
serv.privmsg(channel, 'cronDTC : start !')
self.__prompt('host', '{%alert%}cronDTC : start !{%default%}')
return True
def schedule_execution_time_iterator(
start_timestamp: float, cron_schedule: str,
execution_timezone: Optional[str]) -> Iterator[datetime.datetime]:
timezone_str = execution_timezone if execution_timezone else "UTC"
utc_datetime = pytz.utc.localize(
datetime.datetime.utcfromtimestamp(start_timestamp))
start_datetime = utc_datetime.astimezone(pytz.timezone(timezone_str))
date_iter = croniter(cron_schedule, start_datetime)
# Go back one iteration so that the next iteration is the first time that is >= start_datetime
# and matches the cron schedule
next_date = date_iter.get_prev(datetime.datetime)
check.invariant(is_valid_cron_string(cron_schedule))
cron_parts, _ = croniter.expand(cron_schedule)
is_numeric = [len(part) == 1 and part[0] != "*" for part in cron_parts]
is_wildcard = [len(part) == 1 and part[0] == "*" for part in cron_parts]
delta_fn = None
should_hour_change = False
# Special-case common intervals (hourly/daily/weekly/monthly) since croniter iteration can be
# much slower than adding a fixed interval
if all(is_numeric[0:3]) and all(is_wildcard[3:]): # monthly
delta_fn = lambda d, num: d.add(months=num)
should_hour_change = False
elif all(is_numeric[0:2]) and is_numeric[4] and all(
is_wildcard[2:4]): # weekly
delta_fn = lambda d, num: d.add(weeks=num)
should_hour_change = False
elif all(is_numeric[0:2]) and all(is_wildcard[2:]): # daily
delta_fn = lambda d, num: d.add(days=num)
should_hour_change = False
elif is_numeric[0] and all(is_wildcard[1:]): # hourly
delta_fn = lambda d, num: d.add(hours=num)
should_hour_change = True
else:
delta_fn = None
should_hour_change = False
if delta_fn:
# Use pendulums for intervals when possible
next_date = to_timezone(pendulum.instance(next_date), timezone_str)
while True:
curr_hour = next_date.hour
next_date_cand = delta_fn(next_date, 1)
new_hour = next_date_cand.hour
if not should_hour_change and new_hour != curr_hour:
# If the hour changes during a daily/weekly/monthly schedule, it
# indicates that the time shifted due to falling in a time that doesn't
# exist due to a DST transition (for example, 2:30AM CST on 3/10/2019).
# Instead, execute at the first time that does exist (the start of the hour),
# but return to the original hour for all subsequent executions so that the
# hour doesn't stay different permanently.
check.invariant(new_hour == curr_hour + 1)
yield next_date_cand.replace(minute=0)
next_date_cand = delta_fn(next_date, 2)
check.invariant(next_date_cand.hour == curr_hour)
next_date = next_date_cand
yield next_date
else:
# Otherwise fall back to croniter
while True:
next_date = to_timezone(
pendulum.instance(date_iter.get_next(datetime.datetime)),
timezone_str)
yield next_date
def expand(cls, expr_format, *args, **kwargs):
if len(expr_format.split()) == 6:
raise CroniterBadCronError(
"Expected 'min hour day mon dow'")
return croniter.expand(expr_format, *args, **kwargs)
def is_valid_cron_string(cron_string: str) -> bool:
if not croniter.is_valid(cron_string):
return False
expanded, _ = croniter.expand(cron_string)
# dagster only recognizes cron strings that resolve to 5 parts (e.g. not seconds resolution)
return len(expanded) == 5