aws-cron-expression-validator 1.1.15

ValidatesAWS EventBridge cron expressions, which are similar to, but not compatible with Unix style cron expressions

AWSCronExpressionValidator

Validates these AWS EventBridge cron expressions, which are similar to, but not compatible with Unix style cron expressions;

Field	Values	Wildcards
Minute	0-59	, - * /
Hour	0-23	, - * /
Day-of-month	1-31	, - * ? / L W
Month	1-12 or JAN-DEC	, - * /
Day-of-week	1-7 or SUN-SAT	, - * ? L #
Year	1970-2199	, - * /

• It appears AWS's wildcard support borrows heavily from Quartz Job Scheduler cron expressions. More documentation about wildcard handling than AWS provides is available in the Cron Trigger Tutorial. NB: AWS doesn't support seconds (i.e. AWS has 6 fields, while Quartz has 7), so ignore the first field in the Quartz documenation.

This was inspired by Niloy Chakraborty's AWSCronValidator.py project.

Installing

To install the library run;

pip install aws-cron-expression-validator

Usage

from aws_cron_expression_validator.validator import AWSCronExpressionValidator, AWSCronExpressionMinuteError

my_expression = "0 180 ? * MON-FRI *"
try:
    AWSCronExpressionValidator.validate(my_expression)
except AWSCronExpressionMinuteError as e:
    print(f"Oh no! My expression has an invalid minute field: {e}")
except ValueError as e:
    print(f"Oh no! My expression was invalid: {e}")