python-crontab 1.3

Python Crontab API

Description

Crontab module for read and writing crontab files and accessing the system cron automatically and simply using a direct API.

Comparing the below chart to http://en.wikipedia.org/wiki/Cron#CRON_expression you will note that W, L, # and ? symbols are not supported.

Field Name	Mandatory	Allowed Values	Allowed Special Characters
Minutes	Yes	0-59	* / , -
Hours	Yes	0-23	* / , -
Day of month	Yes	1-31	* / , -
Month	Yes	1-12 or JAN-DEC	* / , -
Day of week	Yes	0-6 or SUN-SAT	* / , -

Supported special cases allow crontab lines to not use fields. These are the supported aliases:

Case	Meaning
@reboot	Every boot
@hourly	0 * * * *
@daily	0 0 * * *
@weekly	0 0 * * 0
@monthly	0 0 1 * *
@yearly	0 0 1 1 *
@annually	0 0 1 1 *
@midnight	0 0 * * *

How to Use the Module

Getting access to a crontab can happen in four ways:

from crontab import CronTab

system_cron = CronTab()
user_cron = CronTab('root')
file_cron = CronTab(tabfile='filename.tab')
mem_cron = CronTab(tab="""
  * * * * * command
""")

Creating a new job is as simple as:

job  = cron.new(command='/usr/bin/echo')

And setting the job’s time restrictions:

job.minute.during(5,50).every(5)
job.hour.every(4)

job.dow.on('SUN')
job.month.during('APR', 'NOV')

Creating a job with a comment:

job = cron.new(command='/foo/bar',comment='SomeID')

Use a special syntax:

job.every_reboot()

Find an existing job by command:

list = cron.find_command('bar')

Clean a job of all rules:

job.clear()

Iterate through all jobs:

for job in cron:
    print job

Iterate through all lines:

for line in cron.lines:
    print job

Remove Items:

cron.remove( job )
cron.remove_all('echo')

Write CronTab back to system or filename:

cron.write()

Write CronTab to new filename:

cron.write( 'output.tab' )

Extra Support

• Support for SunOS with compatability mode

• Python 3.2 and Python 2.7 tested