Moleculer-cron NPM

moleculer-cron

Cron mixin for Moleculer using cron.

Description

Easy to use cron with Moleculer!

Install

$ npm install moleculer-cron --save

Usage

Create cron service

Specify all of your cron tasks inside the settings.cronJobs array of the service.

const CronMixin = require("moleculer-cron");

broker.createService({
    name: "cron-job",

    mixins: [CronMixin],

    settings: {
        cronJobs: [
            {
                name: "jobHelloWorld",
                cronTime: '*/5 * * * * *', // Run every 5 seconds
                manualStart: true, // This job needs to be started manually
                onTick: async function() {
                    this.logger.info('JobHelloWorld ticked');
                    try {
                        const data = await this.broker.call("cron-job.say");
                        this.logger.info("Oh!", data);
                        
                        // Stop this job and start the other one
                        this.stopJob("jobHelloWorld");
                        this.startJob("jobToggle");
                        this.logger.info("Stopped JobHelloWorld and started JobToggle");
                    } catch (e) {
                        this.logger.info("error ", e);
                    }
                },
                onInitialize: function() {
                    this.logger.info("JobHelloWorld is init");
                    // This job is manual start, so it won't start automatically
                },
                onComplete: function() {
                    this.logger.info("JobHelloWorld is stopped");
                }
            },
            {
                name: "jobToggle",
                cronTime: '*/5 * * * * *', // Run every 5 seconds
                onTick: function() {
                    this.logger.info('JobToggle ticked');
                    
                    // Stop this job and start the other one
                    this.stopJob("jobToggle");
                    this.startJob("jobHelloWorld");
                    this.logger.info("Stopped JobToggle and started JobHelloWorld");
                },
                onInitialize: function() {
                    this.logger.info("JobToggle is init");
                    // This job will start automatically
                },
                onComplete: function() {
                    this.logger.info("JobToggle is stopped");
                }
            }
        ]
    },

    actions: {
        say: {
            handler() {
                return "HelloWorld!";
            }
        },
    }
});

Available Cron patterns:

Asterisk. E.g. *
Ranges. E.g. 1-3,5
Steps. E.g. */2

Read up on cron patterns here. Note that this library uses six fields, with 1 second as the finest granularity.

Cron Ranges

Seconds: 0-59
Minutes: 0-59
Hours: 0-23
Day of Month: 1-31
Months: 0-11 (Jan-Dec)
Day of Week: 0-6 (Sun-Sat)

API

Job Configuration

name - REQUIRED - Set a name for the job.
cronTime - REQUIRED - The time to fire off your job. This can be in the form of cron syntax or a JS Date object.
manualStart - OPTIONAL - Specifies whether to start the job just before exiting the constructor. Default is false.
timeZone - OPTIONAL - Specify the timezone for the execution. Check all timezones available at Moment Timezone Website.
onInitialize - OPTIONAL - Executed before the cron job is created.
onStart - OPTIONAL - When the cron is starting.
onStop - OPTIONAL - When the cron is stopping.
onComplete - OPTIONAL - A function that will fire when the job is stopped.
onTick - REQUIRED - The function to fire at the specified time.

Mixin Methods

startJob(jobName) - Starts the specified job.
stopJob(jobName) - Stops the specified job.
getJob(jobName) - Returns the job object for the specified job name.

Job Object Methods

startJob() - Starts the job.
stopJob() - Stops the job.
lastDate() - Returns the last execution date of the job.
running() - Returns whether the job is currently running.
setTime(time) - Changes the time for the job. time can be a cron string or a Date object.
nextDates(count) - Returns an array of the next count dates that the job will run.
addCallback(callback) - Adds an additional callback function to be executed when the job ticks.