Background Job in Parse Server (node/cron)

CloudCode.js

// src/CloudCode.js

"use strict"
var Cron = require('./Cron');
var Job = require('./Job');

class CloudCode {

  constructor(Parse, timezone){
    this.Parse = Parse;
    this.cron = new Cron(timezone);
    this.job = new Job(this.Parse);
  }

  putJob(name, req){
    this.job.put(name, req);
    return this;
  }

  addCron(name, timeFormat){
    this.cron.addJob(timeFormat, this.job.get(name));
    return this;
  }

  start(){
    this.cron.on();
  }

  stop(){
    this.cron.off();
  }

}

module.exports = CloudCode;

Cron.js

// src/Cron.js

"use strict"
class Cron {

  constructor(timezone){
    this.cronJob = require('cron').CronJob;
	  this.jobs = [];
	  this.timezone = timezone;
  }

  addJob(timeFormat, func){
    var job = new this.cronJob(timeFormat, func, null, false, this.timezone);
    this.jobs.push(job);
    return this;
  }

  on(){
    for(let job of this.jobs){
      job.start();
    }
    console.log("cron on");
  }

  off(){
    for(let job of this.jobs){
      job.stop();
    }
    console.log("cron off");
  }

  static getTimeFormat(min, hour, day, month, weekday){
    return [min, hour, day, month, weekday].join(" ");
  }
}

module.exports = Cron;

index.js

// end of index.js in https://github.com/ParsePlatform/parse-server-example

// thanks for shoe116 ( https://github.com/ParsePlatform/parse-server/pull/398 )

// ............... //

// [ CronJob ]
// Seconds: 0-59
// Minutes: 0-59
// Hours: 0-23
// Day of Month: 1-31
// Months: 0-11
// Day of Week: 0-6
if (process.env.NODE_ENV == "production") {
  var Parse = require('parse/node').Parse;
  Parse.initialize(process.env.APP_ID || 'myAppId', null, process.env.MASTER_KEY || '');
  Parse.serverURL = process.env.SERVER_URL || 'http://localhost:1337/parse';

  var CloudCode = require('./src/CloudCode');
  var cloud = new CloudCode(Parse, 'Asia/Seoul');
  cloud.putJob("backgroundJob", null);  // parse cloud function name & param
  cloud.addCron("backgroundJob", "0 */15 * * * *"); // per 15 minutes
  cloud.start();
}

Job.js

// src/Job.js

"use strict"

class Job {

  constructor(Parse){
    this.Parse = Parse;
    this.jobs = {};
  }

  put(name, req){
    var res = {
      success: (message) => {console.log(message)},
      error: (message) => {console.error(message)}
    }
    this.jobs[name] = (function () { this.Parse.Cloud.run(name, req, res); }).bind(this);
    return this;
  }

  get(name){
    return this.jobs[name];
  }

}

module.exports = Job;

package.json

<!-- need add dependencies -->
{
  "dependencies": {
    "cron": "1.1.0"
  }
}

Nice! Thanks! ;-)

This worked for me too, awesome! :D
Do you know if there are any limitations of doing it like this?

I see examples such as this one that run separate clock and worker dynos, and from reading documentation apparently this is required for horizontal scalability.

That example almost worked for me, but the worker dyno crashed after start with no errors, so didn't know how to debug further so am using this instead now :)

Thanks!! It Works for me too :)