quartz-cron-checker 0.1.0

Simple Python library to check if a Quartz cron expression is valid.

quartz-cron-checker

quartz-cron-checker is a lightweight, strict validator for Quartz-style cron expressions in Python.

It ensures all parts of the cron string conform to the Quartz cron spec—including support for special characters, named values, and mutual exclusivity of day-of-month and day-of-week.

Features

• ✅ Full support for 6- or 7-field Quartz cron expressions (second minute hour day-of-month month day-of-week [year])
• ✅ Literal handling (*, ?, L, W, #)
• ✅ Named months (JAN, FEB, etc.) and days (MON, TUE, etc.)
• ✅ Detailed error messages and exceptions
• ✅ Clean object-oriented API
• ✅ Extensible field-level validation

Installation

pip install quartz-cron-checker

Usage

Calling validate will raise an exception if the cron string is invalid. The method will return True otherwise.

from quartz_cron_checker import QuartzCronChecker

# Parse and validate a cron string
cron = QuartzCronChecker.from_cron_string("0 0 12 ? * MON-FRI")
cron.validate()  # Raises if invalid

print(str(cron))  # "0 0 12 ? * MON-FRI"

You can also validate either a whole cron string or individual fields without creating an object:

from quartz_cron_checker import validate_cron_string, validate_year, validate_second

# Validate a full cron string
validate_cron_string("0 0 12 ? * MON-FRI")  # Raises if invalid

# Validate individual fields
validate_second("0")  # Raises if invalid

validate_year("2023")  # Raises if invalid