Cron Schedule Triggers ~ A library for determining Quartz Cron schedule trigger dates.
Cron Schedule Triggers (CSTriggers) is a Python library enabling the ability to determine the next execution of a live schedule. Its syntax is that of Quartz Job Scheduler. This library is not a scheduling app or a task queue, there are plenty of those in the wild to choose from. When you need advanced customisation of triggers for tasks, and a common and conventional syntax for schedule notation, CSTriggers comes to your aid.
Initialize a schedule object with a cron notation string, a start date, and an optional end date. Call .next_trigger()
for a new date. Notice that when an end_date is given, The schedule terminates at 2022-10-13T00:00:00
and not 2030-03-01T00:00:00
as it would naturally.
from cstriggers.core.trigger import QuartzCron
schedule_string = "0 0 0 1 JAN-MAR ? 2010-2030"
start_date = "2019-10-13T00:00:00"
end_date = "2022-10-13T00:00:00"
cron_obj = QuartzCron(schedule_string=schedule_string, start_date=start_date, end_date=end_date)
print(cron_obj.next_trigger(isoformat=True))
>> 2020-01-01T00:00:00
For multiple sequential dates call either .next_trigger()
multiple times.
from cstriggers.core.trigger import QuartzCron
schedule_string = "0 0 0 1 JAN-MAR ? 2010-2030"
start_date = "2019-10-13T00:00:00"
end_date = "2022-10-13T00:00:00"
cron_obj = QuartzCron(schedule_string=schedule_string, start_date=start_date, end_date=end_date)
print(cron_obj.next_trigger(isoformat=True))
print(cron_obj.next_trigger(isoformat=True))
>> 2020-01-01T00:00:00
>> 2020-02-01T00:00:00
Or call .next_triggers()
with the number of triggers needed.
from cstriggers.core.trigger import QuartzCron
schedule_string = "0 0 0 1 JAN-MAR ? 2010-2030"
start_date = "2019-10-13T00:00:00"
end_date = "2022-10-13T00:00:00"
cron_obj = QuartzCron(schedule_string=schedule_string, start_date=start_date, end_date=end_date)
print(cron_obj.next_triggers(number_of_triggers=10, isoformat=True))
>> [
'2020-01-01T00:00:00',
'2020-02-01T00:00:00',
'2020-03-01T00:00:00',
'2021-01-01T00:00:00',
'2021-02-01T00:00:00',
'2021-03-01T00:00:00',
'2022-01-01T00:00:00',
'2022-02-01T00:00:00',
'2022-03-01T00:00:00',
'2023-01-01T00:00:00'
]