These are the tasks that run periodically by the operating system. Users can schedule commands the OS will run these commands automatically according to the given time. We will use a package called node-cron which is a task scheduler in pure JavaScript for node.js. We are also using express as a server. Install the required packages using the command
npm install express node-cron
It is usually used for system admin jobs such as backups, logging, sending newsletters, subscription emails and more.
Syntax:
cron.schedule(“* * * * * *”, function() {
// Task to do
});
Descriptors with their ranges:
Seconds (optional): 0 – 59
Minute: 0 – 59
Hour: 0 – 23
Day of the Month: 1 – 31
Month: 1 – 12
Day of the week: 0 – 7 (0 and 7 both represent Sunday)
Example: Create a new file named index.js and add the following code:
// Importing required libraries
const cron = require(“node-cron”);
const express = require(“express”);
app = express(); // Initializing app
// Creating a cron job which runs on every 10 second
cron.schedule(“*/10 * * * * *”, function() {
console.log(“running a task every 10 second”);
});
app.listen(3000);