Pestras Micro Cron Job

Pestras micro plugin for creating cron jobs.

install

npm i @pestras/micro @pestras/micro-cron

Plugin

import { SERVICE, Micro } from '@pestras/micro';
import { MicroCron } from '@pestras/micro-cron';

Micro.plugins(new MicroCron());

@SERVICE()
class TestService {}

Micro.start(TestService);

CRON Decorator

Using CRON decorator we can register any methods as a cron job specifing scheduling as the first paramerter.

import { SERVICE, Micro } from '@pestras/micro';
import { MicroCron, CRON } from '@pestras/micro-cron';

Micro.plugins(new MicroCron());

@SERVICE()
class TestService {

  // My job method will be called daily on 0 and 6 o'clock.
  @CRON({ hours: [0, 12] })
  myJob() {
    console.log('myJob called successfully');
  }
}

Micro.start(TestService);

Schedule

Corn schedule support months, days, days of week, hours asn minutes.

Each of them supports four types of value

• Interval: As a nummber.
• Range: As a string dash separated range.
• Multi range: An array of string dash separated ranges.
• Specifc: Values as array of numbers.

class SomeService {

  @CRON({
    months: 3 // each three months of a year
    // or
    months: '4-7' // Apr - May - Jun - Jul of each year
    // or
    months: ['2-4', '6-8'] // Feb - Mar - Apr and Jun, Jul, Aug of each year
    // or
    months: [1, 5] // Only Feb and May of each year 
  })
  myJob() {
    console.log('myJob called successfully');
  }
} 

Starting Stoping Jobs:

We can deactive jobs and reactivate using the following MicroCron static methods.

• Start: accepts a job name specified by the neme of the class slash the name of the method lowercased as 'testservice/myjob'.
• Stop: accepts a job name specified by the neme of the class slash the name of the method lowercased as 'testservice/myjob'.
• StopAll: Stop all jobs untill restarted again.
• StartAll: Start all jobs.

Note: Stoping and starting are applied to the schedule, not calling the job method it self.

We can specify an initial state for any job as a second paraneter for the CRON decorator.

CRON({ minutes: 1 }, false) // inactive untill start later, default value is true
myJob() {

}

Sub Services:

CORN can be called on any class method as long it is started by Micro.start method.