test: heartbeats are stamped with the application clock, not the database's NOW() (#51), red

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

cmd/tapir/uploads_test.go

@@ -44,7 +44,7 @@ func (f *fakeUploadsStore) SaveProgress(context.Context, string, string, []domai
 	return nil
 }
 
-func (f *fakeUploadsStore) Heartbeat(context.Context, string, string) error { return nil }
+func (f *fakeUploadsStore) Heartbeat(context.Context, string, string, time.Time) error { return nil }
 
 func (f *fakeUploadsStore) FailInterruptedUploads(context.Context) (int, error) {
 	f.sweeps++

internal/adapters/store/uploaded_transcripts_progress_test.go

@@ -68,13 +68,13 @@ func TestUploadProgress_AHeartbeatMovesAliveAtAndNotProgressAt(t *testing.T) {
 	ctx := context.Background()
 	at := time.Date(2026, 10, 2, 8, 30, 0, 0, time.UTC)
 	require.NoError(t, s.SaveProgress(ctx, userA, id, []domain.ProgressStep{{Key: "audio", Label: "a", State: domain.StepRunning}}, at))
-	before := time.Now().Add(-time.Second)
+	beatAt := at.Add(90 * time.Second) // deliberately not the database's NOW()
 
-	require.NoError(t, s.Heartbeat(ctx, userA, id))
+	require.NoError(t, s.Heartbeat(ctx, userA, id, beatAt))
 
 	got, err := s.GetUpload(ctx, userA, id)
 	require.NoError(t, err)
-	assert.True(t, got.AliveAt.After(before), "the heartbeat must stamp the row with now")
+	assert.True(t, got.AliveAt.Equal(beatAt), "the heartbeat is stamped with the application's clock, the same one progress_at uses, not the database's NOW() (#51)")
 	assert.True(t, got.ProgressAt.Equal(at), "alive is not progress: a heartbeat must not move progress_at")
 }
 
@@ -99,7 +99,7 @@ func TestUploadProgress_ByAnotherUserChangesNothing(t *testing.T) {
 	ctx := context.Background()
 
 	errSave := s.SaveProgress(ctx, userB, id, []domain.ProgressStep{{Key: "x", Label: "X", State: domain.StepDone}}, time.Now())
-	errBeat := s.Heartbeat(ctx, userB, id)
+	errBeat := s.Heartbeat(ctx, userB, id, time.Now())
 
 	assert.ErrorIs(t, errSave, store.ErrUploadNotFound)
 	assert.ErrorIs(t, errBeat, store.ErrUploadNotFound)

internal/progress/tracker_stall_test.go

@@ -28,7 +28,7 @@ func (s *stallSink) SaveProgress(ctx context.Context, _ []domain.ProgressStep, _
 	return ctx.Err()
 }
 
-func (s *stallSink) Beat(ctx context.Context) error {
+func (s *stallSink) Beat(ctx context.Context, _ time.Time) error {
 	s.beats.Add(1)
 	<-ctx.Done()
 	return ctx.Err()

internal/progress/tracker_test.go

@@ -17,11 +17,12 @@ import (
 
 // fakeSink records every saved snapshot and every heartbeat.
 type fakeSink struct {
-	mu    sync.Mutex
+	mu     sync.Mutex
-	saves [][]domain.ProgressStep
+	saves  [][]domain.ProgressStep
-	at    []time.Time
+	at     []time.Time
-	beats int
+	beats  int
-	err   error
+	beatAt []time.Time
+	err    error
 }
 
 func (f *fakeSink) SaveProgress(_ context.Context, steps []domain.ProgressStep, at time.Time) error {
@@ -32,10 +33,11 @@ func (f *fakeSink) SaveProgress(_ context.Context, steps []domain.ProgressStep,
 	return f.err
 }
 
-func (f *fakeSink) Beat(context.Context) error {
+func (f *fakeSink) Beat(_ context.Context, at time.Time) error {
 	f.mu.Lock()
 	defer f.mu.Unlock()
 	f.beats++
+	f.beatAt = append(f.beatAt, at)
 	return f.err
 }
 
@@ -297,7 +299,7 @@ func (r *retainingSink) SaveProgress(_ context.Context, steps []domain.ProgressS
 	r.got = append(r.got, steps)
 	return nil
 }
-func (r *retainingSink) Beat(context.Context) error { return nil }
+func (r *retainingSink) Beat(context.Context, time.Time) error { return nil }
 
 func TestTracker_ASnapshotHandedToTheSinkIsNotChangedByLaterTransitions(t *testing.T) {
 	sink := &retainingSink{}
@@ -400,3 +402,20 @@ func TestTracker_AnnotateAttachesANoteToAStepAndSavesItAtOnce(t *testing.T) {
 	require.Equal(t, "20 min of the 79 the file claimed", sink.last(t)[0].Note)
 	require.NotPanics(t, func() { tr.Annotate("no-such-step", "x") })
 }
+
+func TestTracker_BeatIsStampedWithTheTrackersClock(t *testing.T) {
+	// alive_at used the database's NOW() while the page compared it with the application
+	// clock; a skewed database clock showed a healthy job as lost (#51).
+	tr, sink, clk, _ := newTracker(t)
+	clk.tick(42 * time.Second)
+	want := clk.now()
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	go tr.Heartbeat(ctx, 5*time.Millisecond, time.Hour)
+
+	require.Eventually(t, func() bool { return sink.beatCount() >= 1 }, 2*time.Second, 5*time.Millisecond)
+	sink.mu.Lock()
+	defer sink.mu.Unlock()
+	require.True(t, sink.beatAt[0].Equal(want), "beat stamped %v, the tracker's clock says %v", sink.beatAt[0], want)
+}

internal/uploads/worker_test.go

@@ -70,7 +70,7 @@ func (s *wStore) SaveProgress(_ context.Context, _, _ string, steps []domain.Pro
 	return nil
 }
 
-func (s *wStore) Heartbeat(context.Context, string, string) error {
+func (s *wStore) Heartbeat(context.Context, string, string, time.Time) error {
 	time.Sleep(s.beatDelay)
 	s.mu.Lock()
 	defer s.mu.Unlock()