Add sync triggers debounce (#2631)

go.mod

@@ -4,6 +4,7 @@ go 1.19
 
 require (
 	github.com/Shopify/sarama v1.37.2
+	github.com/bep/debounce v1.2.1
 	github.com/dchest/uniuri v1.2.0
 	github.com/docopt/docopt-go v0.0.0-20180111231733-ee0de3bc6815
 	github.com/dustin/go-humanize v1.0.0

go.sum

@@ -119,6 +119,8 @@ github.com/beorn7/perks v0.0.0-20180321164747-3a771d992973/go.mod h1:Dwedo/Wpr24
 github.com/beorn7/perks v1.0.0/go.mod h1:KWe93zE9D1o94FZ5RNwFwVgaQK1VOXiVxmqh+CedLV8=
 github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
 github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=
+github.com/bep/debounce v1.2.1 h1:v67fRdBA9UQu2NhLFXrSg0Brw7CexQekrBwDMM8bzeY=
+github.com/bep/debounce v1.2.1/go.mod h1:H8yggRPQKLUhUoqrJC1bO2xNya7vanpDl7xR3ISbCJ0=
 github.com/blend/go-sdk v1.20220112.5 h1:M1H3KB++HyPAek31WH2HNut1Xg1SI7LyT9giNE2fcPQ=
 github.com/blend/go-sdk v1.20220112.5/go.mod h1:STLiO8ZA8doHtRV7QfW2mXgH/8U+85GHY9ge3phM3dY=
 github.com/cenkalti/backoff v2.2.1+incompatible h1:tNowT99t7UNflLxfYYSlKYsBpXdEet03Pg2g16Swow4=

pkg/router/httpTriggers.go

@@ -22,6 +22,7 @@ import (
 	"strings"
 	"time"
 
+	"github.com/bep/debounce"
 	"github.com/gorilla/mux"
 	"go.uber.org/zap"
 	kerrors "k8s.io/apimachinery/pkg/api/errors"
@@ -60,6 +61,7 @@ type HTTPTriggerSet struct {
 	isDebugEnv                 bool
 	svcAddrUpdateThrottler     *throttler.Throttler
 	unTapServiceTimeout        time.Duration
+	syncDebouncer              func(func())
 }
 
 func makeHTTPTriggerSet(logger *zap.Logger, fmap *functionServiceMap, fissionClient versioned.Interface,
@@ -77,6 +79,7 @@ func makeHTTPTriggerSet(logger *zap.Logger, fmap *functionServiceMap, fissionCli
 		isDebugEnv:                 isDebugEnv,
 		svcAddrUpdateThrottler:     actionThrottler,
 		unTapServiceTimeout:        unTapServiceTimeout,
+		syncDebouncer:              debounce.New(time.Millisecond * 20),
 	}
 	httpTriggerSet.triggerInformer = utils.GetInformersForNamespaces(fissionClient, time.Minute*30, fv1.HttpTriggerResource)
 	httpTriggerSet.funcInformer = utils.GetInformersForNamespaces(fissionClient, time.Minute*30, fv1.FunctionResource)
@@ -368,7 +371,9 @@ func (ts *HTTPTriggerSet) runInformer(ctx context.Context, informer map[string]k
 }
 
 func (ts *HTTPTriggerSet) syncTriggers() {
-	ts.updateRouterRequestChannel <- struct{}{}
+	ts.syncDebouncer(func() {
+		ts.updateRouterRequestChannel <- struct{}{}
+	})
 }
 
 func (ts *HTTPTriggerSet) updateRouter() {