Merge pull request #1302 from aduffeck/debouncer

Do not run the timout func if the work func has run

services/search/pkg/search/debouncer.go

@@ -24,7 +24,7 @@ type workItem struct {
 	t       *time.Timer
 	timeout *time.Timer
 
-	trigger func()
+	work func()
 }
 
 type AckFunc func() error
@@ -54,7 +54,8 @@ func (d *SpaceDebouncer) Debounce(id *provider.StorageSpaceId, ack AckFunc) {
 		return
 	}
 
-	trigger := func() {
+	wi := &workItem{}
+	wi.work = func() {
 		if _, ok := d.inProgress.Load(id.OpaqueId); ok {
 			// Reschedule this run for when the previous run has finished
 			d.mutex.Lock()
@@ -66,9 +67,12 @@ func (d *SpaceDebouncer) Debounce(id *provider.StorageSpaceId, ack AckFunc) {
 		}
 
 		d.mutex.Lock()
+		wi.timeout.Stop() // stop the timeout timer if it is running
 		delete(d.pending, id.OpaqueId)
 		d.inProgress.Store(id.OpaqueId, true)
-		defer d.inProgress.Delete(id.OpaqueId)
+		defer func() {
+			d.inProgress.Delete(id.OpaqueId)
+		}()
 		d.mutex.Unlock() // release the lock early to allow other goroutines to debounce
 
 		d.f(id)
@@ -80,16 +84,13 @@ func (d *SpaceDebouncer) Debounce(id *provider.StorageSpaceId, ack AckFunc) {
 			}
 		}()
 	}
-	t := time.AfterFunc(d.after, trigger)
+	wi.t = time.AfterFunc(d.after, wi.work)
+	wi.timeout = time.AfterFunc(d.timeout, func() {
+		d.log.Debug().Msg("timeout while waiting for space debouncer to finish")
+		wi.t.Stop()
+		wi.work()
+	})
 
-	d.pending[id.OpaqueId] = &workItem{
-		trigger: trigger,
-		t:       t,
-		timeout: time.AfterFunc(d.timeout, func() {
-			d.log.Debug().Msg("timeout while waiting for space debouncer to finish")
-			t.Stop()
-			trigger()
-		}),
-	}
+	d.pending[id.OpaqueId] = wi
 
 }

services/search/pkg/search/debouncer_test.go

@@ -115,6 +115,26 @@ var _ = Describe("SpaceDebouncer", func() {
 		}, "300ms").Should(Equal(1))
 	})
 
+	It("doesn't run the timeout function if the work function has been called", func() {
+		debouncer = search.NewSpaceDebouncer(100*time.Millisecond, 250*time.Millisecond, func(id *sprovider.StorageSpaceId) {
+			if id.OpaqueId == "spaceid" {
+				callCount.Add(1)
+			}
+		}, log.NewLogger())
+
+		// Initial call to start the timers
+		debouncer.Debounce(spaceid, nil)
+
+		// Wait for the debounce timer to fire
+		Eventually(func() int {
+			return int(callCount.Load())
+		}, "200ms").Should(Equal(1))
+
+		// The timeout function should not be called
+		time.Sleep(300 * time.Millisecond)
+		Expect(int(callCount.Load())).To(Equal(1))
+	})
+
 	It("calls the ack function when the debounce fires", func() {
 		var ackCalled atomic.Bool
 		ackFunc := func() error {