How to get a Node.js function to run once on the last day of each month

nodejs-cron.js

const moment = require('moment');

const someAction = () => console.log('Actioning...');

const wait = ms => new Promise((resolve, reject) => setTimeout(resolve, ms));

const startCron = async () => {
  while (true) {
    if (
      moment().date() ===
      moment()
        .endOf('month')
        .date()
    ) {
      someAction();
    }
    await wait(moment.duration(1, 'day').asMilliseconds());
  }
};

console.log('Starting cron service...');
startCron();

For more information on the the moment library, have a look at https://momentjs.com/

A walkthrough of this gist is here https://youtu.be/xOr6KDA-jXw