add another out channel so we can properly report lastRun (#700)

* add another out channel so we can properly report lastRun

* don't block on channel send

* add tests

executor.go

@@ -15,7 +15,8 @@ type executor struct {
 	logger                 Logger
 	stopCh                 chan struct{}
 	jobsIn                 chan jobIn
-	jobIDsOut        chan uuid.UUID
+	jobsOutForRescheduling chan uuid.UUID
+	jobsOutCompleted       chan uuid.UUID
 	jobOutRequest          chan jobOutRequest
 	stopTimeout            time.Duration
 	done                   chan error
@@ -122,7 +123,7 @@ func (e *executor) start() {
 							// all runners are busy, reschedule the work for later
 							// which means we just skip it here and do nothing
 							// TODO when metrics are added, this should increment a rescheduled metric
-							e.sendOutToScheduler(&jIn)
+							e.sendOutForRescheduling(&jIn)
 						}
 					} else {
 						// since we're not using LimitModeReschedule, but instead using LimitModeWait
@@ -131,7 +132,7 @@ func (e *executor) start() {
 						// at which point this call would block.
 						// TODO when metrics are added, this should increment a wait metric
 						e.limitMode.in <- jIn
-						e.sendOutToScheduler(&jIn)
+						e.sendOutForRescheduling(&jIn)
 					}
 				} else {
 					// no limit mode, so we're either running a regular job or
@@ -167,17 +168,17 @@ func (e *executor) start() {
 							select {
 							case runner.rescheduleLimiter <- struct{}{}:
 								runner.in <- jIn
-								e.sendOutToScheduler(&jIn)
+								e.sendOutForRescheduling(&jIn)
 							default:
 								// runner is busy, reschedule the work for later
 								// which means we just skip it here and do nothing
 								// TODO when metrics are added, this should increment a rescheduled metric
-								e.sendOutToScheduler(&jIn)
+								e.sendOutForRescheduling(&jIn)
 							}
 						} else {
 							// wait mode, fill up that queue (buffered channel, so it's ok)
 							runner.in <- jIn
-							e.sendOutToScheduler(&jIn)
+							e.sendOutForRescheduling(&jIn)
 						}
 					} else {
 						select {
@@ -206,10 +207,10 @@ func (e *executor) start() {
 	}
 }
 
-func (e *executor) sendOutToScheduler(jIn *jobIn) {
+func (e *executor) sendOutForRescheduling(jIn *jobIn) {
 	if jIn.shouldSendOut {
 		select {
-		case e.jobIDsOut <- jIn.id:
+		case e.jobsOutForRescheduling <- jIn.id:
 		case <-e.ctx.Done():
 			return
 		}
@@ -250,7 +251,7 @@ func (e *executor) limitModeRunner(name string, in chan jobIn, wg *waitGroupWith
 								return
 							case <-j.ctx.Done():
 								return
-							case e.jobIDsOut <- j.id:
+							case e.jobsOutForRescheduling <- j.id:
 							}
 						}
 						// remove the limiter block, as this particular job
@@ -331,20 +332,24 @@ func (e *executor) runJob(j internalJob, jIn jobIn) {
 
 	if e.elector != nil {
 		if err := e.elector.IsLeader(j.ctx); err != nil {
-			e.sendOutToScheduler(&jIn)
+			e.sendOutForRescheduling(&jIn)
 			return
 		}
 	} else if e.locker != nil {
 		lock, err := e.locker.Lock(j.ctx, j.name)
 		if err != nil {
-			e.sendOutToScheduler(&jIn)
+			e.sendOutForRescheduling(&jIn)
 			return
 		}
 		defer func() { _ = lock.Unlock(j.ctx) }()
 	}
 	_ = callJobFuncWithParams(j.beforeJobRuns, j.id, j.name)
 
-	e.sendOutToScheduler(&jIn)
+	e.sendOutForRescheduling(&jIn)
+	select {
+	case e.jobsOutCompleted <- j.id:
+	case <-e.ctx.Done():
+	}
 
 	startTime := time.Now()
 	err := callJobFuncWithParams(j.function, j.parameters...)

job.go

@@ -24,7 +24,9 @@ type internalJob struct {
 	name   string
 	tags   []string
 	jobSchedule
-	lastRun, nextRun   time.Time
+	lastScheduledRun   time.Time
+	nextScheduled      time.Time
+	lastRun            time.Time
 	function           any
 	parameters         []any
 	timer              clockwork.Timer
@@ -681,18 +683,18 @@ func (d dailyJob) next(lastRun time.Time) time.Time {
 
 func (d dailyJob) nextDay(lastRun time.Time, firstPass bool) time.Time {
 	for _, at := range d.atTimes {
-		// sub the at time hour/min/sec onto the lastRun's values
+		// sub the at time hour/min/sec onto the lastScheduledRun's values
 		// to use in checks to see if we've got our next run time
 		atDate := time.Date(lastRun.Year(), lastRun.Month(), lastRun.Day(), at.Hour(), at.Minute(), at.Second(), lastRun.Nanosecond(), lastRun.Location())
 
 		if firstPass && atDate.After(lastRun) {
 			// checking to see if it is after i.e. greater than,
-			// and not greater or equal as our lastRun day/time
+			// and not greater or equal as our lastScheduledRun day/time
 			// will be in the loop, and we don't want to select it again
 			return atDate
 		} else if !firstPass && !atDate.Before(lastRun) {
 			// now that we're looking at the next day, it's ok to consider
-			// the same at time that was last run (as lastRun has been incremented)
+			// the same at time that was last run (as lastScheduledRun has been incremented)
 			return atDate
 		}
 	}
@@ -727,18 +729,18 @@ func (w weeklyJob) nextWeekDayAtTime(lastRun time.Time, firstPass bool) time.Tim
 			// weekDayDiff is used to add the correct amount to the atDate day below
 			weekDayDiff := wd - lastRun.Weekday()
 			for _, at := range w.atTimes {
-				// sub the at time hour/min/sec onto the lastRun's values
+				// sub the at time hour/min/sec onto the lastScheduledRun's values
 				// to use in checks to see if we've got our next run time
 				atDate := time.Date(lastRun.Year(), lastRun.Month(), lastRun.Day()+int(weekDayDiff), at.Hour(), at.Minute(), at.Second(), lastRun.Nanosecond(), lastRun.Location())
 
 				if firstPass && atDate.After(lastRun) {
 					// checking to see if it is after i.e. greater than,
-					// and not greater or equal as our lastRun day/time
+					// and not greater or equal as our lastScheduledRun day/time
 					// will be in the loop, and we don't want to select it again
 					return atDate
 				} else if !firstPass && !atDate.Before(lastRun) {
 					// now that we're looking at the next week, it's ok to consider
-					// the same at time that was last run (as lastRun has been incremented)
+					// the same at time that was last run (as lastScheduledRun has been incremented)
 					return atDate
 				}
 			}
@@ -795,7 +797,7 @@ func (m monthlyJob) nextMonthDayAtTime(lastRun time.Time, days []int, firstPass
 	for _, day := range days {
 		if day >= lastRun.Day() {
 			for _, at := range m.atTimes {
-				// sub the day, and the at time hour/min/sec onto the lastRun's values
+				// sub the day, and the at time hour/min/sec onto the lastScheduledRun's values
 				// to use in checks to see if we've got our next run time
 				atDate := time.Date(lastRun.Year(), lastRun.Month(), day, at.Hour(), at.Minute(), at.Second(), lastRun.Nanosecond(), lastRun.Location())
 
@@ -807,12 +809,12 @@ func (m monthlyJob) nextMonthDayAtTime(lastRun time.Time, days []int, firstPass
 
 				if firstPass && atDate.After(lastRun) {
 					// checking to see if it is after i.e. greater than,
-					// and not greater or equal as our lastRun day/time
+					// and not greater or equal as our lastScheduledRun day/time
 					// will be in the loop, and we don't want to select it again
 					return atDate
 				} else if !firstPass && !atDate.Before(lastRun) {
 					// now that we're looking at the next month, it's ok to consider
-					// the same at time that was  lastRun (as lastRun has been incremented)
+					// the same at time that was  lastScheduledRun (as lastScheduledRun has been incremented)
 					return atDate
 				}
 			}
@@ -892,7 +894,7 @@ func (j job) NextRun() (time.Time, error) {
 	if ij == nil || ij.id == uuid.Nil {
 		return time.Time{}, ErrJobNotFound
 	}
-	return ij.nextRun, nil
+	return ij.nextScheduled, nil
 }
 
 func (j job) Tags() []string {

scheduler.go

@@ -110,7 +110,8 @@ func NewScheduler(options ...SchedulerOption) (Scheduler, error) {
 		logger:           &noOpLogger{},
 
 		jobsIn:                 make(chan jobIn),
-		jobIDsOut:     make(chan uuid.UUID),
+		jobsOutForRescheduling: make(chan uuid.UUID),
+		jobsOutCompleted:       make(chan uuid.UUID),
 		jobOutRequest:          make(chan jobOutRequest, 1000),
 		done:                   make(chan error),
 	}
@@ -147,8 +148,11 @@ func NewScheduler(options ...SchedulerOption) (Scheduler, error) {
 		s.logger.Info("gocron: new scheduler created")
 		for {
 			select {
-			case id := <-s.exec.jobIDsOut:
+			case id := <-s.exec.jobsOutForRescheduling:
-				s.selectExecJobIDsOut(id)
+				s.selectExecJobsOutForRescheduling(id)
+
+			case id := <-s.exec.jobsOutCompleted:
+				s.selectExecJobsOutCompleted(id)
 
 			case in := <-s.newJobCh:
 				s.selectNewJob(in)
@@ -287,14 +291,14 @@ func (s *scheduler) selectRemoveJob(id uuid.UUID) {
 
 // Jobs coming back from the executor to the scheduler that
 // need to evaluated for rescheduling.
-func (s *scheduler) selectExecJobIDsOut(id uuid.UUID) {
+func (s *scheduler) selectExecJobsOutForRescheduling(id uuid.UUID) {
 	j, ok := s.jobs[id]
 	if !ok {
 		// the job was removed while it was running, and
 		// so we don't need to reschedule it.
 		return
 	}
-	j.lastRun = j.nextRun
+	j.lastScheduledRun = j.nextScheduled
 
 	// if the job has a limited number of runs set, we need to
 	// check how many runs have occurred and stop running this
@@ -313,7 +317,7 @@ func (s *scheduler) selectExecJobIDsOut(id uuid.UUID) {
 		}
 	}
 
-	next := j.next(j.lastRun)
+	next := j.next(j.lastScheduledRun)
 	if next.IsZero() {
 		// the job's next function will return zero for OneTime jobs.
 		// since they are one time only, they do not need rescheduling.
@@ -329,7 +333,7 @@ func (s *scheduler) selectExecJobIDsOut(id uuid.UUID) {
 			next = j.next(next)
 		}
 	}
-	j.nextRun = next
+	j.nextScheduled = next
 	j.timer = s.clock.AfterFunc(next.Sub(s.now()), func() {
 		// set the actual timer on the job here and listen for
 		// shut down events so that the job doesn't attempt to
@@ -347,6 +351,15 @@ func (s *scheduler) selectExecJobIDsOut(id uuid.UUID) {
 	s.jobs[id] = j
 }
 
+func (s *scheduler) selectExecJobsOutCompleted(id uuid.UUID) {
+	j, ok := s.jobs[id]
+	if !ok {
+		return
+	}
+	j.lastRun = s.now()
+	s.jobs[id] = j
+}
+
 func (s *scheduler) selectJobOutRequest(out jobOutRequest) {
 	if j, ok := s.jobs[out.id]; ok {
 		select {
@@ -386,7 +399,7 @@ func (s *scheduler) selectNewJob(in newJobIn) {
 				}
 			})
 		}
-		j.nextRun = next
+		j.nextScheduled = next
 	}
 
 	s.jobs[j.id] = j
@@ -437,7 +450,7 @@ func (s *scheduler) selectStart() {
 				}
 			})
 		}
-		j.nextRun = next
+		j.nextScheduled = next
 		s.jobs[id] = j
 	}
 	select {

scheduler_test.go

@@ -1398,6 +1398,29 @@ func TestScheduler_RemoveLotsOfJobs(t *testing.T) {
 	}
 }
 
+func TestScheduler_RemoveJob_RemoveSelf(t *testing.T) {
+	goleak.VerifyNone(t)
+	s := newTestScheduler(t)
+	s.Start()
+
+	_, err := s.NewJob(
+		DurationJob(100*time.Millisecond),
+		NewTask(func() {}),
+		WithEventListeners(
+			BeforeJobRuns(
+				func(jobID uuid.UUID, jobName string) {
+					s.RemoveByTags("tag1")
+				},
+			),
+		),
+		WithTags("tag1"),
+	)
+	require.NoError(t, err)
+
+	time.Sleep(time.Millisecond * 400)
+	assert.NoError(t, s.Shutdown())
+}
+
 func TestScheduler_WithEventListeners(t *testing.T) {
 	goleak.VerifyNone(t)
 
@@ -1673,6 +1696,67 @@ func TestScheduler_RunJobNow(t *testing.T) {
 	}
 }
 
+func TestScheduler_LastRunSingleton(t *testing.T) {
+	goleak.VerifyNone(t)
+
+	tests := []struct {
+		name string
+		f    func(t *testing.T, j Job)
+	}{
+		{
+			"simple",
+			func(t *testing.T, j Job) {},
+		},
+		{
+			"with runNow",
+			func(t *testing.T, j Job) {
+				runTime := time.Now()
+				assert.NoError(t, j.RunNow())
+
+				// because we're using wait mode we need to wait here
+				// to make sure the job queued with RunNow has finished running
+				time.Sleep(time.Millisecond * 200)
+				lastRun, err := j.LastRun()
+				assert.NoError(t, err)
+				assert.LessOrEqual(t, lastRun.Sub(runTime), time.Millisecond*125)
+				assert.GreaterOrEqual(t, lastRun.Sub(runTime), time.Millisecond*75)
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			s := newTestScheduler(t)
+			j, err := s.NewJob(
+				DurationJob(time.Millisecond*100),
+				NewTask(func() {
+					time.Sleep(time.Millisecond * 200)
+				}),
+				WithSingletonMode(LimitModeWait),
+			)
+			require.NoError(t, err)
+
+			startTime := time.Now()
+			s.Start()
+
+			lastRun, err := j.LastRun()
+			assert.NoError(t, err)
+			assert.True(t, lastRun.IsZero())
+
+			time.Sleep(time.Millisecond * 200)
+
+			lastRun, err = j.LastRun()
+			assert.NoError(t, err)
+			assert.LessOrEqual(t, lastRun.Sub(startTime), time.Millisecond*125)
+			assert.GreaterOrEqual(t, lastRun.Sub(startTime), time.Millisecond*75)
+
+			tt.f(t, j)
+
+			assert.NoError(t, s.Shutdown())
+		})
+	}
+}
+
 func TestScheduler_OneTimeJob(t *testing.T) {
 	tests := []struct {
 		name    string
@@ -1796,7 +1880,7 @@ func TestScheduler_WithMonitor(t *testing.T) {
 		jobName string
 	}{
 		{
-			"scheduler with monitorer",
+			"scheduler with monitor",
 			DurationJob(time.Millisecond * 50),
 			"job",
 		},