Method run

cron.go:239–305

run the scheduler.. this is private just due to the need to synchronize access to the 'running' state variable.

()

// run the scheduler.. this is private just due to the need to synchronize
// access to the 'running' state variable.
func (c *Cron) run() {
	c.logger.Info("start")

	// Figure out the next activation times for each entry.
	now := c.now()
	for _, entry := range c.entries {
		entry.Next = entry.Schedule.Next(now)
		c.logger.Info("schedule", "now", now, "entry", entry.ID, "next", entry.Next)
	}

	for {
		// Determine the next entry to run.
		sort.Sort(byTime(c.entries))

		var timer *time.Timer
		if len(c.entries) == 0 || c.entries[0].Next.IsZero() {
			// If there are no entries yet, just sleep - it still handles new entries
			// and stop requests.
			timer = time.NewTimer(100000 * time.Hour)
		} else {
			timer = time.NewTimer(c.entries[0].Next.Sub(now))
		}

		for {
			select {
			case now = <-timer.C:
				now = now.In(c.location)
				c.logger.Info("wake", "now", now)

				// Run every entry whose next time was less than now
				for _, e := range c.entries {
					if e.Next.After(now) || e.Next.IsZero() {
						break
					}
					c.startJob(e.WrappedJob)
					e.Prev = e.Next
					e.Next = e.Schedule.Next(now)
					c.logger.Info("run", "now", now, "entry", e.ID, "next", e.Next)
				}

			case newEntry := <-c.add:
				timer.Stop()
				now = c.now()
				newEntry.Next = newEntry.Schedule.Next(now)
				c.entries = append(c.entries, newEntry)
				c.logger.Info("added", "now", now, "entry", newEntry.ID, "next", newEntry.Next)

			case replyChan := <-c.snapshot:
				replyChan <- c.entrySnapshot()
				continue

			case <-c.stop:
				timer.Stop()
				c.logger.Info("stop")
				return

			case id := <-c.remove:
				timer.Stop()