humancron

Table of Contents

Typescript library for turning cron expressions into human-readable strings.

Formats a cron expression into a human readable string.

https://www.npmjs.com/package/humancron

Installation
#

npm install --save humancron

API
#

formatCronAsString(expression: string): string
#

Parses a cron expression and formats it into a human readable string.

The expression can be made up of five parts (standard cron) or six, where the first element is seconds.

formatCronAsString("10 5 5 * *")
"At 05:10 of the 5th day of every month"

formatCronAsString("20 10 5 5 5 5")
"At 05:10:20 of the 5th day and every Friday of May"

formatCronAsString("10-30 * 1-12 * *")
"At every minute between the 10th through the 30th minute of every hour of every day between the 1st through the 12th day of every month"

formatCronAsString("* 5-10/2 * JAN-MAY/3 MON-WED")
"At every minute of every 2nd hour between the 5th through the 10th hour of every day between Monday through Wednesday of every 3rd month between January through May"

formatCronAsObject(expression: string): FormattedExpression
#

Does the same formatting as formatCronAsString(expression: string): string without joining the separate parts together.

This will give you an object with the string for second, minute, hour, dayOfMonth, month and dayOfWeek separately. The object also includes information on whether the time part has been simplified into clock (HH:MM:SS) format.

formatCronAsObject("10-30 * 1-12 * *")

{
  second: null,
  minute: 'every minute between the 10th through the 30th minute',
  hour: 'every hour',
  dayOfMonth: 'every day between the 1st through the 12th day',
  month: 'every month',
  dayOfWeek: '',
  timeAsClock: false,
  clockHasSeconds: false
}

parseExpression(expression: string): ParsedExpression
#

Parses a cron expression. Used internally but might be useful in certain use cases.

parseExpression("10-30 * 1-12 * *")

{
  second: null,
  minute: {
    ranges: [
      {
        from: 10,
        to: 30,
        step: 1
      }
    ]
  },
  hour: {
    ranges: [
      {
        from: 0,
        to: 23,
        step: 1
      }
    ]
  },
  dayOfMonth: {
    ranges: [
      {
        from: 1,
        to: 12,
        step: 1
      }
    ]
  },
  month: {
    ranges: [
      {
        from: 1,
        to: 12,
        step: 1
      }
    ]
  },
  dayOfWeek: {
    ranges: [
      {
        from: 1,
        to: 7,
        step: 1
      }
    ]
  }
}