Node.js Project to Build a Cron Job Task Scheduler Using Node-Cron Library in Javascript Full Tutorial

Welcome folks today in this blog post we will be building a cron job task scheduler in node.js using node-cron library in javascript. All the full source code of the application is shown below.

Get Started

In order to get started you need to install the below library using the below command as shown below

npm i node-cron

After installing the library make an index.js file for your node.js app and copy paste the below code

Now we will be executing the tasks every minute in node.js as shown below

var cron = require('node-cron');

cron.schedule('* * * * *', () => {
  console.log('running a task every minute');
});

var cron = require('node-cron');

cron.schedule('* * * * *', () => {

console.log('running a task every minute');

});

As you can see we are importing the node-cron module and then we are using the schedule method to schedule the tasks to run every minute. These * represents the different sets of time available in node-cron module.

# ┌────────────── second (optional)
 # │ ┌──────────── minute
 # │ │ ┌────────── hour
 # │ │ │ ┌──────── day of month
 # │ │ │ │ ┌────── month
 # │ │ │ │ │ ┌──── day of week
 # │ │ │ │ │ │
 # │ │ │ │ │ │
 # * * * * * *

# ┌────────────── second (optional)

# │ ┌──────────── minute

# │ │ ┌────────── hour

# │ │ │ ┌──────── day of month

# │ │ │ │ ┌────── month

# │ │ │ │ │ ┌──── day of week

# │ │ │ │ │ │

# * * * * * *

Allowed values

field	value
second	0-59
minute	0-59
hour	0-23
day of month	1-31
month	1-12 (or names)
day of week	0-7 (or names, 0 or 7 are sunday)

Using Multiple Values

You can even provide multiple time intervals to run the node.js code using this cron module as shown below

var cron = require('node-cron');

cron.schedule('1,2,4,5 * * * *', () => {
  console.log('running every minute 1, 2, 4 and 5');
});

var cron = require('node-cron');

cron.schedule('1,2,4,5 * * * *', () => {

console.log('running every minute 1, 2, 4 and 5');

});

Or you can even provide the range values as well

var cron = require('node-cron');

cron.schedule('1-5 * * * *', () => {
  console.log('running every minute to 1 from 5');
});

var cron = require('node-cron');

cron.schedule('1-5 * * * *', () => {

console.log('running every minute to 1 from 5');

});