cron-time-converter

Convert natural language scheduling phrases into standard 5-field cron expressions.

Installation

npm install cron-time-converter

Usage

import { parse } from "cron-time-converter";

parse("every minute");           // "* * * * *"
parse("every 5 minutes");        // "*/5 * * * *"
parse("every hour");             // "0 * * * *"
parse("every 6 hours");          // "0 */6 * * *"
parse("every day");              // "0 0 * * *"
parse("every day at 3pm");       // "0 15 * * *"
parse("every day at 11:30pm");   // "30 23 * * *"
parse("every day at 12pm");      // "0 12 * * *"  (noon)
parse("every day at 12am");      // "0 0 * * *"   (midnight)
parse("every weekday");          // "0 0 * * 1-5"
parse("every weekend");          // "0 0 * * 0,6"
parse("every sunday");           // "0 0 * * 0"
parse("every friday at 5:30pm"); // "30 17 * * 5"
parse("every month");            // "0 0 1 * *"
parse("every month on day 15");  // "0 0 15 * *"

// Unsupported / ambiguous input
parse("every fortnight");        // "ERROR"
parse("do something");           // "ERROR"

API

parse(input: string): string

Converts a natural language phrase to a 5-field cron expression.

| Parameter | Type | Description | |-----------|----------|--------------------------------| | input | string | Natural language schedule phrase |

Returns the cron expression string, or "ERROR" if the input is unsupported or ambiguous.

Supported patterns

| Input pattern | Output | |---------------------------------|---------------------| | every minute | * * * * * | | every X minutes | */X * * * * | | every hour | 0 * * * * | | every X hours | 0 */X * * * | | every day | 0 0 * * * | | every day at H(:MM)am/pm | MM HH * * * | | every weekday | 0 0 * * 1-5 | | every weekend | 0 0 * * 0,6 | | every <dayname> | 0 0 * * N | | every <dayname> at H(:MM)am/pm| MM HH * * N | | every month | 0 0 1 * * | | every month on day N | 0 0 N * * |

Time parsing rules

• Times use 12-hour am/pm format: 3pm, 3:30pm, 11:45am
• 12pm → noon (12:00)
• 12am → midnight (00:00)
• 0am → midnight (00:00)
• When no time is specified for a day-based schedule, midnight (00:00) is used

Day names

Full names (sunday, monday, …saturday) and 3-letter abbreviations (sun, mon, …sat) are both accepted. All input is case-insensitive.