Heroku clock process already runs job when pushed to server

Question

I'm using the Heroku clock process to schedule jobs to run. This is my procfile.

web: node index.js
worker: node worker.js
clock: node clock.js

The following is my clock.js, which should run every 30th minute of the hour.

const CronJob = require('cron').CronJob;
const worker = require('./worker');

const job = new CronJob({
    cronTime: "30 */1 * * *",
    onTick: worker.start(),
    timeZone: "Asia/Ho_Chi_Minh"
});

job.start();

My worker.js holds the code to be executed

exports.start = () => {
    // Code to be ran
};

The issue when I push changes to Heroku, the code is executed straight away by my clock dyno, and at 30 past the hour nothing is happening.

Any idea if I'm missing something?

Answer 1

Try removing the () at the end of worker.start. The parentheses make the function run immediately.

Answer 2

This way you are starting the worker at the same Clock's Dyno. You should use RabbitMQ or something similar