cron-scheduler

cron-scheduler

Runs jobs in periodic intervals

cron-scheduler is a way to run functions at specific times of the day. It runs in Node.js as well as the browser.

It requires a Promise implementation to work. If you're on Node.js v4 or later, you should be fine. Otherwise, you'll also need to install bluebird, rsvp, when, or [q.js][].

cron()

cron(options, function)

Starts a cronjob.

cron({ on: '0 9 * * *' }, function () {
  console.log('this will run every 9:00am')
})

You can pass more options.

• on (String, required) - the schedule in cron format (min hour day month day-of-week).
• timezone (String) - the timezone to run it in.
• name (String) - identifier to show in the debug logs. Means nothing if debugging is off.

cron({
  timezone: 'Asia/Manila'
  on: '0 9 * * *',
  name: 'dostuff'
} , function () {
  console.log('this will run every 9:00am')
})

The options.on parameter is in cron standard format. Check the cron cheatsheet for more details.

Any errors will be thrown, and will stop the scheduler. If this is not what you want, you may wish to decorate the function being passed.

cron({ on: '0 9 * * *' }, trap(work))

function trap (fn) {
  return function () {
    return Promise.resolve(fn.apply(this, arguments))
      .catch(function (err) {
        // do stuff.
        // this handler will work for both promise rejections
        // *and* regular errors.
      })
  }
}

If function returns a Promise, it will wait for it to finish before scheduling the next job. If the promise is rejected, it will be an unhandled rejection (!). You may use the same trap() decorator trick above to get around this.

To stop the cronjob, just run the stop method returned by cron().

job = cron({ on: '0 12 * * *' }, work)
job.stop()

To manually invoke the cronjob, run the run method returned by cron().

job = cron({ on: '0 12 * * *' }, work)
job.run()

cron.debug

cron.debug(function)

Sets the debug function.

cron.debug(console.log.bind(console))

You can pass your custom logger here. For instance, you can use the debug module for prettier messages.

cron.debug(require('debug')('cron'))