croner

What is croner?

The croner npm package is a high-performance task scheduler for Node.js that allows you to run tasks at specific times or intervals. It is designed to be a drop-in replacement for the 'cron' package with additional features and improvements.

What are croner's main functionalities?

Simple cron job scheduling

This feature allows you to schedule a task to run at intervals defined by the cron syntax. In the provided code sample, a job is scheduled to run every 5 seconds.

const { Cron } = require('croner');

const job = Cron('*/5 * * * * *', () => {
  console.log('This will run every 5 seconds');
});

One-time execution

This feature allows you to schedule a task to run once at a specific time in the future. The code sample schedules a job to run once after 10 seconds.

const { Cron } = require('croner');

const job = Cron(new Date(Date.now() + 10000), () => {
  console.log('This will run once after 10 seconds');
});

Stopping a job

This feature allows you to stop a scheduled job. In the code sample, a job is scheduled to run every 5 seconds but is stopped after 15 seconds.

const { Cron } = require('croner');

const job = Cron('*/5 * * * * *', () => {
  console.log('This job will be stopped.');
});

setTimeout(() => {
  job.stop();
}, 15000);

Timezone support

This feature allows you to schedule jobs according to a specific timezone. The code sample schedules a job to run at 10:30 AM in the 'America/New_York' timezone.

const { Cron } = require('croner');

const job = Cron('0 30 10 * * *', () => {
  console.log('This will run at 10:30 AM in the America/New_York timezone.');
}, { timezone: 'America/New_York' });

Other packages similar to croner

node-schedule

node-schedule is a flexible cron-like and not-cron-like job scheduler for Node.js. It allows you to schedule jobs using both cron-style and human-readable syntax. It is similar to croner but offers a different API and additional scheduling features like scheduling jobs with JavaScript Date objects.

agenda

agenda is a job scheduling library for Node.js that uses MongoDB for persisting job data. It is more suitable for distributed or long-running job tasks. Unlike croner, which focuses on in-memory cron job scheduling, agenda provides persistence and is better suited for applications that require job recovery and failover capabilities.

bull

bull is a Redis-based queue system for Node.js. It is designed for handling distributed jobs and messages in Node.js applications. While croner is used for scheduling tasks, bull is more focused on job queuing, processing, and concurrency, making it suitable for more complex job handling scenarios.

README

Croner

Pure JavaScript Isomorphic cron parser and scheduler without dependencies.

Installation

Node.js

npm install croner

Browser (AMD and regular usage)

Download lib/croner.js and import with script-tag or AMD as usual.

Usage

var o = cron( <string pattern> );
o.next( [ <date previous> ] );
o.msToNext();
var job = o.schedule( [ { startAt: <date>, stopAt: <date>, maxRuns: <integer> } ,] callback);
job.pause();
job.resume();
job.stop();

Examples

Parsing only

// Parse 14:00:00 at next sunday
var parser = cron('0 0 14 * * 7');

// Log the actual date object of next run
console.log(parser.next());

// Log number of milliseconds to next run
console.log(parser.msToNext());`

Basic scheduling

// Run every minute
var scheduler = cron('0 * * * * *');

scheduler.schedule(function() {
	console.log('This will run every minute.');
});

Scheduling with options

// Run every minute
var scheduler = cron('0 * * * * *');

// Schedule with options (all options are optional)
scheduler.schedule({ maxRuns: 5 }, function() {
	console.log('This will run every minute.');
});

Pattern

┌──────────────── sec (0 - 59)
│ ┌────────────── min (0 - 59)
│ │ ┌──────────── hour (0 - 23)
│ │ │ ┌────────── day of month (1 - 31)
│ │ │ │ ┌──────── month (1 - 12)
│ │ │ │ │ ┌────── day of week (0 - 6) 
│ │ │ │ │ │       (0 to 6 are Sunday to Saturday; 7 is Sunday, the same as 0)
│ │ │ │ │ │
* * * * * *

License

MIT