Handle Unix format Crontab(eg: */30 [9-17]/2 1,2,3 * *)
const cron = require("unix-cron");
const c = new cron("*/30 [9-17]/2 1,2,3 * *");
// check if a Date match this cron
c.isMatchDate(new Date());
// get next Date of the cron
c.next();
c.next(new Date("2021-01-01 1:1:0"));
// schedule missions
c.schedule(() => {
// do stuff
});