Cronparse

A simple tool for testing crontab like syntax.

Usage

>>> from cronparse import Cron
>>> c = Cron('*/5 * * * 0')  # Matches only on Mondays, every 5th minute
>>> from datetime import datetime
>>> d = datetime(2020, 4, 13, 11, 5)
>>> c.matches(d)
True
>>> d = d.replace(minute=6)
>>> c.matches(d)
False
>>> d = d.replace(day=14, minute=5)
>>> c.matches(d)
False
>>> c.why(d) # Ask which fragment of the rule did not match
[True, True, True, True, False]

crontab rule syntax

Supported syntax:

1. * - match any value
2. 1 - match exact value
3. */5 - match every 5th value
4. 1,3,4 - match values from list
5. 1-3 - match values in a range
6. 1-3,7,*/2 - combinations!
7. @yearly, @annually, @monthly, @weekly, @daily, @midnight, @hourly

Unsupported syntax:

• Day names
• Month names
• @reboot

Timezone Support

Optionally, you can pass a datetime.tzinfo as the second argument. It defaults to datetime.timezone.utc.

Any datetime passed for testing will first be moved to that timezone.