scheduler.go

// RunJobAt wait until the Stop() function has been called on the run
// or the specified time for the run is after the present time.
func (ot *OneTime) RunJobAt(initr models.Initiator, job models.JobSpec) {
	select {
	case <-ot.done:
	case <-ot.Clock.After(initr.Time.DurationFromNow()):
		if initr.Ran {
			logger.Error((fmt.Errorf("Job runner: Initiator: %v cannot be run more than once", initr.ID)))
			return
		}

		initr.Ran = true
		_, err := BeginRun(job, initr, models.RunResult{}, ot.Store)
		if err != nil {
			logger.Error(err.Error())
		}
	}
}

scheduler_test.go

func TestOneTime_RunJobAt_RunTwice(t *testing.T) {
	t.Parallel()

	store, cleanup := cltest.NewStore()
	defer cleanup()

	ot := services.OneTime{
		Clock: store.Clock,
		Store: store,
	}

	j, initr := cltest.NewJobWithRunAtInitiator(time.Now())
	assert.Nil(t, store.SaveJob(&j))
	
	ot.RunJobAt(initr, j)
	initr.Time = models.Time{Time: time.Now().Add(time.Second * 2)}
	ot.RunJobAt(initr, j)

	jobRuns := []models.JobRun{}
	assert.Nil(t, store.Where("JobID", j.ID, &jobRuns))
	assert.Equal(t, 1, len(jobRuns))

}