Natural Cron ⏰⏰

Natural Cron is a easy-to-use Node.js library for creating and validating cron expressions with natural, human-readable APIs.

Features

• Chainable methods for constructing cron expressions.
• Validation of cron components (minute, hour, day of the month, month, day of the week).
• Helpful error messages for invalid input.
• TypeScript support for strong typing and intellisense.

Installation

Install using npm:

npm install natural-cron

Or using yarn:

yarn add natural-cron

Usages

Utilize CronExpressionBuilder to generate cron expressions for various scheduling scenarios.

const { CronExpressionBuilder, CronValidators } = require('natural-cron');
const schedule = new  CronExpressionBuilder();

📋 Examples Table

| 📅 Description | 💻 Code Example | ⏰ Cron Expression | |----------------------------------------------------|---------------------------------------------------------------------------------------------------------------------|------------------------| | Run a job at 5:30 PM every day | schedule.atTime('17:30').compile(); | 30 17 * * * | | Run at 9 AM on weekdays | schedule.atTime('09:00').onWeekDays([1,2,3,4,5]).compile(); | 0 9 * * 1-5 | | Run at noon on the 1st and 15th of the month | schedule.atTime('12:00').onDaysOfMonth([1, 15]).compile(); | 0 12 1,15 * * | | Run at midnight during January and July | schedule.atTime('00:00').duringMonths([1, 7]).compile(); | 0 0 * 1,7 * | | Run every 15 minutes | schedule.everyX(15, CronTimeUnit.Minute).compile(); | */15 * * * * | | Run every day at noon | schedule.every('day').atHours([12]).compile(); | 0 12 * * * | | Run every Sunday at 5 PM | schedule.onWeekDays([0]).atHours([17]).compile(); | 0 17 * * 0 | | Run the 1st day of every month at 1 AM | schedule.onDaysOfMonth([1]).every('month').atHours([1]).compile(); | 0 1 1 * * | | Run every weekday at 8:30 AM | schedule.atTime("08:30").onWeekDays([1, 2, 3, 4, 5]).compile(); | 30 8 * * 1-5 | | Run every 6 hours | schedule.everyX(6, CronTimeUnit.Hour).compile(); | 0 */6 * * * | | Run every quarter at midnight | schedule.duringMonths([1, 4, 7, 10]).onDaysOfMonth([1]).atTime("00:00").compile(); | 0 0 1 1,4,7,10 * | | Run every Saturday and Sunday at 10:15 AM | schedule.atTime("10:15").onWeekDays([6, 0]).compile(); | 15 10 * * 6,0 | | Run at 9 AM, 12 PM, and 3 PM every day | schedule.every('day').atHours([9, 12, 15]).compile(); | 0 9,12,15 * * * | | Run at 7 AM, 2 PM, and 10 PM on Tuesdays | schedule.atHours([7, 14, 22]).onWeekDays([2]).compile(); | 0 7,14,22 * * 2 | | Run at 20 past every hour on the 5th of July | schedule.atMinutes([20]).onDaysOfMonth([5]).duringMonths([7]).compile(); | 20 * 5 7 * | | Run every 5 minutes during office hours - every() | schedule.every('minute').atMinutes([0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55]).atHours([9, 10, 11, 12, 13, 14, 15, 16]).compile(); | 0,5,10,15,20,25,30,35,40,45,50,55 9-16 * * * | | Run every 5 minutes during office hours - everyX() | schedule.everyX(5,CronTimeUnit.Minute).atHours([9, 10, 11, 12, 13, 14, 15, 16]).compile() | */5 9-16 * * * | | Run at quarter past and quarter to every hour | schedule.every('hour').atMinutes([15, 45]).compile(); | 15,45 * * * * |

Note: schedule is an instance of CronExpressionBuilder utilized for generating the cron expressions.

API Reference

CronExpressionBuilder

• atMinutes(minutes: Array<number>): this
• atHours(hours: Array<number>): this
• atTime(time: string): this
• every(unit: string): this
• everyX(interval: number, unit: ScheduleUnit): this
• onWeekdays(days: Array<number>): this
• onDaysOfMonth(days: Array<number>): this
• duringMonths(months: Array<number>): this
• compile(): string - Get the cron expression

Use CronTimeUnit enum for ScheduleUnit

export enum CronTimeUnit {
  Minute = 'minute',
  Hour = 'hour',
  DayOfMonth = 'dayOfMonth',
  Month = 'month',
  DayOfWeek = 'dayOfWeek',
}

CronValidators

Static methods for validating cron expression components.

• validateMinute(minute: number)
• validateHour(hour: number)
• validateDayOfMonth(day: number)
• validateMonth(month: number)
• validateDayOfWeek(day: number)
• validateTime(time: string)

Contributing

Contributions are welcome! Please feel free to submit a pull request.

License

This project is licensed under the MIT License.