def _delta_to_next(self, last_run_at, next_hour, next_minute, next_second):
"""Find next delta.
Takes a :class:`~datetime.datetime` of last run, next minute and hour,
and returns a :class:`~celery.utils.time.ffwd` for the next
scheduled day and time.
Only called when ``day_of_month`` and/or ``month_of_year``
cronspec is specified to further limit scheduled task execution.
"""
datedata = AttributeDict(year=last_run_at.year)
days_of_month = sorted(self.day_of_month)
months_of_year = sorted(self.month_of_year)
def day_out_of_range(year, month, day):
try:
datetime(year=year, month=month, day=day)
except ValueError:
return True
return False
def roll_over():
for _ in range(2000):
flag = (datedata.dom == len(days_of_month) or day_out_of_range(
datedata.year, months_of_year[datedata.moy],
days_of_month[datedata.dom]) or (self.maybe_make_aware(
datetime(datedata.year, months_of_year[datedata.moy],
days_of_month[datedata.dom])) < last_run_at))
if flag:
datedata.dom = 0
datedata.moy += 1
if datedata.moy == len(months_of_year):
datedata.moy = 0
datedata.year += 1
else:
break
else:
# Tried 2000 times, we're most likely in an infinite loop
raise RuntimeError('unable to rollover, '
'time specification is probably invalid')
if last_run_at.month in self.month_of_year:
datedata.dom = bisect(days_of_month, last_run_at.day)
datedata.moy = bisect_left(months_of_year, last_run_at.month)
else:
datedata.dom = 0
datedata.moy = bisect(months_of_year, last_run_at.month)
if datedata.moy == len(months_of_year):
datedata.moy = 0
roll_over()
while 1:
th = datetime(year=datedata.year,
month=months_of_year[datedata.moy],
day=days_of_month[datedata.dom])
if th.isoweekday() % 7 in self.day_of_week:
break
datedata.dom += 1
roll_over()
return ffwd(year=datedata.year,
month=months_of_year[datedata.moy],
day=days_of_month[datedata.dom],
hour=next_hour,
minute=next_minute,
second=next_second,
microsecond=0)
