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deno_cron

A smart cron Job scheduler library for Deno. It allows you to write human readable cron syntax with tons of flexibility. Writing cron syntax and operation can be very tadious for many developers. This extensions provides very developer friendly api to write any job scheduler’s cron syntax you need.

Deno Cron

Installation:

import {cron, daily, monthly, weekly} from 'https://deno.land/x/deno_cron/cron.ts';

daily(() => {
    backupDatabase();
});


weekly(() => {
    sendNewsLetter();
});

// Runs the Job on 5th day of every month
monthly(() => {
    sendUsageReport();
}, 5);

// Run Job in every 30 minutes
cron('1 */30 * * * *', () => {
    checkStock();
});

Writing CRON Job:

Here is the CRON style syntax to write tons of custom cron schedule.

*    *    *    *    *    *
┬    ┬    ┬    ┬    ┬    ┬
│    │    │    │    │    │
│    │    │    │    │    └ day of week (0 - 7) (0 or 7 is Sunday)
│    │    │    │    └───── month (1 - 12)
│    │    │    └────────── day of month (1 - 31)
│    │    └─────────────── hour (0 - 23)
│    └──────────────────── minute (0 - 59)
└───────────────────────── second (0 - 59) - [Optional 01 as default]

Syntax Table:

Field Required Allowed Values Allowed Special Character
Seconds No 0-59 / - , *
Minute Yes 0-59 / - , *
Hour Yes 0-23 / - , *
Day of Month Yes 1-31 / - , *
Month Yes 1-12 / - , *
Day of Week Yes 0-6 (0 is Sunday) / - , *

Example:

// This Job will be executed 1st day of every month at mid-night.
cron('1 0 0 1 */1 *', () => {
    sendMails();
});

// Job will be executed for 1st to 7th day of every month on 3rd, 6th and 9th hour and every 30 minutes if it's monday

cron('1 */30 3,6,9 1-7 */1 1', () => {
    sendMails();
});

API:

Function Parameter
cron(schedule, job) schedule: string required - cron syntax, job: func required - function to be executed
everyMinute(job) job: func required - function to be executed
every15Minute(job) job: func required - function to be executed
hourly(job) job: func required - function to be executed
daily(job) job: func required - function to be executed
weekly(job, weekDay?) job: func required - function to be executed, weekDay: string or number {optional} - Represents weekday; 0-6, (0 represents Sunday) default: 1
biweekly(job) job: func required - function to be executed
monthly(job, dayOfMonth) job: func required - function to be executed, dayOfMonth: string or number {optional} - 1-31, default: 1
yearly(job) job: func required - function to be executed
stop() - Stop all the scheduled job
start() - If schedulers have been stopped before then starts again

Change Log:

  • Initial version released on - 23-05-2020

Contributors:

Rahul Baruri

License

Distributed under the MIT License.

https://github.com/rbrahul/deno_cron/blob/master/README.md

Developed with ❤️ for Deno community