cron_range

Displays the next N number of executions for a given cron expression. Now with support for AWS EventBridge expressions!

Comes with a cronrange library based on croniter that you can run from the CLI, or from an API built with AWS Chalice and API Gateway on cronrange.info.

Usage

Web

Visit cronrange.info

CLI

python chalicelib/cronrange.py

Options

Option	Description	Default value
-c/--cron	A cron expression (string)	None
-n/--executions	Number of next executions to show.	5
-d/--start-date	Date and time in DD.MM.YYYY. HH:MM format from which to calculate cron executions.	Current date and time.

Examples

python chalicelib/cronrange.py -c "*/5 * * * *"
python chalicelib/cronrange.py -c "5 * * * *" -d "23.11.1999. 19:30"
python chalicelib/cronrange.py -c "5 * * * *" -d "23.11.1999. 19:30" -n 50

# AWS EventBridge compatible expressions
python chalicelib/cronrange.py -c "15 12 * * ? *"
python chalicelib/cronrange.py -c "0 10 1 JAN,FEB,MAR ? *" -d "28.11.2021. 20:00"
python chalicelib/cronrange.py -c "0/50 8-17 ? * THU-FRI *" -d "27.11.2021. 19:30" -n 50

Local API server

make local
curl -H "Content-Type:application/json" \
 -d '{"executions": "10", "cron":"*/5 * * * *"}' \
 localhost:8000

JSON structure

Key	Description	Default value
cron	A cron expression (string)	None
executions	Number of next executions to show.	10
start_date	Date and time in DD.MM.YYYY. HH:MM format from which to calculate cron executions.	Current date and time.

AWS EventBridge support

AWS EventBridge implementation of cron does not use 0 based day of week, instead it is 1-7 SUN-SAT (instead of 0-6), as well as supporting additional expression features such as first-weekday and last-day-of-month. Source

Because of that, cronrange does not support the full range of expression wildcards available on AWS EventBridge.

Wildcard	Example expression	Supported
L	*/5 * L * ? *	Yes
W	*/30 * 1W * ? *	No
#	*/30 * ? * 3#2 *	No
?	0 8 1 * ? *	Yes

Classic cron expression wildcards such as ,, /, - and * are supported.

For developers

Virtualenv setup

make venv

Running tests

make test

Running a local server

make local