crontools 0.1.6

Python cron tools

crontools is a library that allows you to parse crontab expression and iterate over scheduled fire times.

Features:

• crontab expression parser

• optional seconds field support

• optional year field support

• crontab fire time sequential iteration support

Installation

You can install crontools with pip:

$ pip install crontools

Quickstart

Get next cron fire time:

>>> import datetime as dt
>>> import crontools as ct
>>>
>>> tz = dt.timezone.utc
>>> now = dt.datetime.fromisoformat('2020-02-29 23:59:59.999+00:00')
>>> ct = ct.Crontab.parse(
...     '* * * * * * *',
...     seconds_ext=True,
...     years_ext=True,
...     tz=tz,
... )
>>>
>>> print(f"Next fire time: {ct.next_fire_time(now=now)}")
Next fire time: 2020-03-01 00:00:00+00:00

Iteration over cron fire times starting from now:

>>> import crontools as ct
>>>
>>> tz = dt.timezone.utc
>>> now = dt.datetime.fromisoformat('2021-02-01 00:00:00+00:00')
>>> ct = ct.Crontab.parse(
...     '30 30 12-16/2 1,2 JAN SAT,SUN *',
...     seconds_ext=True,
...     years_ext=True,
...     tz=tz,
... )
>>>
>>> cron_iter = ct.iter(start_from=now)
>>> for n, fire_datetime in zip(range(1, 31), cron_iter):
...     print("{n:2}: {dt}".format(n=n, dt=fire_datetime))
...
...
 1: 2022-01-01 12:30:30+00:00
 2: 2022-01-01 14:30:30+00:00
 3: 2022-01-01 16:30:30+00:00
 4: 2022-01-02 12:30:30+00:00
 5: 2022-01-02 14:30:30+00:00
 6: 2022-01-02 16:30:30+00:00
 7: 2022-01-08 12:30:30+00:00
 8: 2022-01-08 14:30:30+00:00
 9: 2022-01-08 16:30:30+00:00
10: 2022-01-09 12:30:30+00:00
11: 2022-01-09 14:30:30+00:00
12: 2022-01-09 16:30:30+00:00
13: 2022-01-15 12:30:30+00:00
14: 2022-01-15 14:30:30+00:00
15: 2022-01-15 16:30:30+00:00
16: 2022-01-16 12:30:30+00:00
17: 2022-01-16 14:30:30+00:00
18: 2022-01-16 16:30:30+00:00
19: 2022-01-22 12:30:30+00:00
20: 2022-01-22 14:30:30+00:00
21: 2022-01-22 16:30:30+00:00
22: 2022-01-23 12:30:30+00:00
23: 2022-01-23 14:30:30+00:00
24: 2022-01-23 16:30:30+00:00
25: 2023-01-01 12:30:30+00:00
26: 2023-01-01 14:30:30+00:00
27: 2023-01-01 16:30:30+00:00
28: 2023-01-02 12:30:30+00:00
29: 2023-01-02 14:30:30+00:00
30: 2023-01-02 16:30:30+00:00