Added config to EventCorrelator in client-go

Added CorrelatorOptions that contains options to change the
defaults in EventSourceObjectSpamFilter and EventAggregator
in EventCorrelator. Added a eventCorrelator property to the
eventBroadcasterImpl to help with this.

Kubernetes-commit: 9d8e6fb1b9cf2d3fac8139a97334287e33ff911f

tools/record/event.go

@@ -50,6 +50,40 @@ type EventSink interface {
 	Patch(oldEvent *v1.Event, data []byte) (*v1.Event, error)
 }
 
+// CorrelatorOptions allows you to change the default of the EventSourceObjectSpamFilter
+// and EventAggregator in EventCorrelator
+type CorrelatorOptions struct {
+	// The lru cache size used for both EventSourceObjectSpamFilter and the EventAggregator
+	// If not specified (zero value), the default specified in events_cache.go will be picked
+	// This means that the LRUCacheSize has to be greater than 0.
+	LRUCacheSize int
+	// The burst size used by the token bucket rate filtering in EventSourceObjectSpamFilter
+	// If not specified (zero value), the default specified in events_cache.go will be picked
+	// This means that the BurstSize has to be greater than 0.
+	BurstSize int
+	// The fill rate of the token bucket in queries per second in EventSourceObjectSpamFilter
+	// If not specified (zero value), the default specified in events_cache.go will be picked
+	// This means that the QPS has to be greater than 0.
+	QPS float32
+	// The func used by the EventAggregator to group event keys for aggregation
+	// If not specified (zero value), EventAggregatorByReasonFunc will be used
+	KeyFunc EventAggregatorKeyFunc
+	// The func used by the EventAggregator to produced aggregated message
+	// If not specified (zero value), EventAggregatorByReasonMessageFunc will be used
+	MessageFunc EventAggregatorMessageFunc
+	// The number of events in an interval before aggregation happens by the EventAggregator
+	// If not specified (zero value), the default specified in events_cache.go will be picked
+	// This means that the MaxEvents has to be greater than 0
+	MaxEvents int
+	// The amount of time in seconds that must transpire since the last occurrence of a similar event before it is considered new by the EventAggregator
+	// If not specified (zero value), the default specified in events_cache.go will be picked
+	// This means that the MaxIntervalInSeconds has to be greater than 0
+	MaxIntervalInSeconds int
+	// The clock used by the EventAggregator to allow for testing
+	// If not specified (zero value), clock.RealClock{} will be used
+	Clock clock.Clock
+}
+
 // EventRecorder knows how to record events on behalf of an EventSource.
 type EventRecorder interface {
 	// Event constructs an event from the given information and puts it in the queue for sending.
@@ -97,16 +131,31 @@ type EventBroadcaster interface {
 
 // Creates a new event broadcaster.
 func NewBroadcaster() EventBroadcaster {
-	return &eventBroadcasterImpl{watch.NewBroadcaster(maxQueuedEvents, watch.DropIfChannelFull), defaultSleepDuration}
+	return &eventBroadcasterImpl{
+		Broadcaster:   watch.NewBroadcaster(maxQueuedEvents, watch.DropIfChannelFull),
+		sleepDuration: defaultSleepDuration,
+	}
 }
 
 func NewBroadcasterForTests(sleepDuration time.Duration) EventBroadcaster {
-	return &eventBroadcasterImpl{watch.NewBroadcaster(maxQueuedEvents, watch.DropIfChannelFull), sleepDuration}
+	return &eventBroadcasterImpl{
+		Broadcaster:   watch.NewBroadcaster(maxQueuedEvents, watch.DropIfChannelFull),
+		sleepDuration: sleepDuration,
+	}
+}
+
+func NewBroadcasterWithCorrelatorOptions(options CorrelatorOptions) EventBroadcaster {
+	return &eventBroadcasterImpl{
+		Broadcaster:   watch.NewBroadcaster(maxQueuedEvents, watch.DropIfChannelFull),
+		sleepDuration: defaultSleepDuration,
+		options:       options,
+	}
 }
 
 type eventBroadcasterImpl struct {
 	*watch.Broadcaster
 	sleepDuration time.Duration
+	options       CorrelatorOptions
 }
 
 // StartRecordingToSink starts sending events received from the specified eventBroadcaster to the given sink.
@@ -116,7 +165,7 @@ func (eventBroadcaster *eventBroadcasterImpl) StartRecordingToSink(sink EventSin
 	// The default math/rand package functions aren't thread safe, so create a
 	// new Rand object for each StartRecording call.
 	randGen := rand.New(rand.NewSource(time.Now().UnixNano()))
-	eventCorrelator := NewEventCorrelator(clock.RealClock{})
+	eventCorrelator := NewEventCorrelatorWithOptions(eventBroadcaster.options)
 	return eventBroadcaster.StartEventWatcher(
 		func(event *v1.Event) {
 			recordToSink(sink, event, eventCorrelator, randGen, eventBroadcaster.sleepDuration)

tools/record/events_cache.go

@@ -443,6 +443,52 @@ func NewEventCorrelator(clock clock.Clock) *EventCorrelator {
 	}
 }
 
+func NewEventCorrelatorWithOptions(options CorrelatorOptions) *EventCorrelator {
+	optionsWithDefaults := populateDefaults(options)
+	spamFilter := NewEventSourceObjectSpamFilter(optionsWithDefaults.LRUCacheSize,
+		optionsWithDefaults.BurstSize, optionsWithDefaults.QPS, optionsWithDefaults.Clock)
+	return &EventCorrelator{
+		filterFunc: spamFilter.Filter,
+		aggregator: NewEventAggregator(
+			optionsWithDefaults.LRUCacheSize,
+			optionsWithDefaults.KeyFunc,
+			optionsWithDefaults.MessageFunc,
+			optionsWithDefaults.MaxEvents,
+			optionsWithDefaults.MaxIntervalInSeconds,
+			optionsWithDefaults.Clock),
+		logger: newEventLogger(optionsWithDefaults.LRUCacheSize, optionsWithDefaults.Clock),
+	}
+}
+
+// populateDefaults populates the zero value options with defaults
+func populateDefaults(options CorrelatorOptions) CorrelatorOptions {
+	if options.LRUCacheSize == 0 {
+		options.LRUCacheSize = maxLruCacheEntries
+	}
+	if options.BurstSize == 0 {
+		options.BurstSize = defaultSpamBurst
+	}
+	if options.QPS == 0 {
+		options.QPS = defaultSpamQPS
+	}
+	if options.KeyFunc == nil {
+		options.KeyFunc = EventAggregatorByReasonFunc
+	}
+	if options.MessageFunc == nil {
+		options.MessageFunc = EventAggregatorByReasonMessageFunc
+	}
+	if options.MaxEvents == 0 {
+		options.MaxEvents = defaultAggregateMaxEvents
+	}
+	if options.MaxIntervalInSeconds == 0 {
+		options.MaxIntervalInSeconds = defaultAggregateIntervalInSeconds
+	}
+	if options.Clock == nil {
+		options.Clock = clock.RealClock{}
+	}
+	return options
+}
+
 // EventCorrelate filters, aggregates, counts, and de-duplicates all incoming events
 func (c *EventCorrelator) EventCorrelate(newEvent *v1.Event) (*EventCorrelateResult, error) {
 	if newEvent == nil {