Merge pull request #93600 from ialidzhikov/fix/readyz-panic

Fix panic on /readyz

Kubernetes-commit: ec560b9737537be8c688776461bc700e8ddedb9d

Godeps/Godeps.json

@@ -676,7 +676,7 @@
 		},
 		{
 			"ImportPath": "k8s.io/client-go",
-			"Rev": "6ecbef177593"
+			"Rev": "00dbcca6ee44"
 		},
 		{
 			"ImportPath": "k8s.io/component-base",

go.mod

@@ -43,7 +43,7 @@ require (
 	gopkg.in/yaml.v2 v2.2.8
 	k8s.io/api v0.0.0-20200731065412-4859c9473977
 	k8s.io/apimachinery v0.0.0-20200726131235-945d4ebf362b
-	k8s.io/client-go v0.0.0-20200731171655-6ecbef177593
+	k8s.io/client-go v0.0.0-20200802132507-00dbcca6ee44
 	k8s.io/component-base v0.0.0-20200731172211-756196c2cad2
 	k8s.io/klog/v2 v2.2.0
 	k8s.io/kube-openapi v0.0.0-20200427153329-656914f816f9
@@ -56,6 +56,6 @@ require (
 replace (
 	k8s.io/api => k8s.io/api v0.0.0-20200731065412-4859c9473977
 	k8s.io/apimachinery => k8s.io/apimachinery v0.0.0-20200726131235-945d4ebf362b
-	k8s.io/client-go => k8s.io/client-go v0.0.0-20200731171655-6ecbef177593
+	k8s.io/client-go => k8s.io/client-go v0.0.0-20200802132507-00dbcca6ee44
 	k8s.io/component-base => k8s.io/component-base v0.0.0-20200731172211-756196c2cad2
 )

go.sum

@@ -509,7 +509,7 @@ honnef.co/go/tools v0.0.0-20190523083050-ea95bdfd59fc/go.mod h1:rf3lG4BRIbNafJWh
 honnef.co/go/tools v0.0.1-2019.2.3/go.mod h1:a3bituU0lyd329TUQxRnasdCoJDkEUEAqEt0JzvZhAg=
 k8s.io/api v0.0.0-20200731065412-4859c9473977/go.mod h1:dWsX+vGcHv9rDhMoQlwkI/sGwaGI1AZERZK/rETJ3Ao=
 k8s.io/apimachinery v0.0.0-20200726131235-945d4ebf362b/go.mod h1:oE8UQU9DqIIc9PyIEYxTj/oJECzZLymCEU9dL0H4F+o=
-k8s.io/client-go v0.0.0-20200731171655-6ecbef177593/go.mod h1:ch2F5aVooSVNJ55V1uSp2dvmtscdaYZpIJhHtP9l3eY=
+k8s.io/client-go v0.0.0-20200802132507-00dbcca6ee44/go.mod h1:ch2F5aVooSVNJ55V1uSp2dvmtscdaYZpIJhHtP9l3eY=
 k8s.io/component-base v0.0.0-20200731172211-756196c2cad2/go.mod h1:GF/5EP2ReckoUAM2elxg5g/5o2ukJ3ydokI2WuF5bCs=
 k8s.io/gengo v0.0.0-20200413195148-3a45101e95ac/go.mod h1:ezvh/TsK7cY6rbqRK0oQQ8IAqLxYwwyPxAX1Pzy0ii0=
 k8s.io/klog/v2 v2.0.0/go.mod h1:PBfzABfn139FHAV07az/IF9Wp1bkk3vpT2XSJ76fSDE=

pkg/server/healthz/healthz.go

@@ -20,6 +20,7 @@ import (
 	"bytes"
 	"fmt"
 	"net/http"
+	"reflect"
 	"strings"
 	"sync"
 	"sync/atomic"
@@ -29,7 +30,6 @@ import (
 	"k8s.io/apimachinery/pkg/util/wait"
 	"k8s.io/apiserver/pkg/endpoints/metrics"
 	"k8s.io/apiserver/pkg/server/httplog"
-	"k8s.io/client-go/informers"
 	"k8s.io/klog/v2"
 )
 
@@ -82,16 +82,20 @@ func (l *log) Check(_ *http.Request) error {
 	return fmt.Errorf("logging blocked")
 }
 
+type cacheSyncWaiter interface {
+	WaitForCacheSync(stopCh <-chan struct{}) map[reflect.Type]bool
+}
+
 type informerSync struct {
-	sharedInformerFactory informers.SharedInformerFactory
+	cacheSyncWaiter cacheSyncWaiter
 }
 
 var _ HealthChecker = &informerSync{}
 
-// NewInformerSyncHealthz returns a new HealthChecker that will pass only if all informers in the given sharedInformerFactory sync.
-func NewInformerSyncHealthz(sharedInformerFactory informers.SharedInformerFactory) HealthChecker {
+// NewInformerSyncHealthz returns a new HealthChecker that will pass only if all informers in the given cacheSyncWaiter sync.
+func NewInformerSyncHealthz(cacheSyncWaiter cacheSyncWaiter) HealthChecker {
 	return &informerSync{
-		sharedInformerFactory: sharedInformerFactory,
+		cacheSyncWaiter: cacheSyncWaiter,
 	}
 }
 
@@ -104,8 +108,8 @@ func (i *informerSync) Check(_ *http.Request) error {
 	// Close stopCh to force checking if informers are synced now.
 	close(stopCh)
 
-	var informersByStarted map[bool][]string
-	for informerType, started := range i.sharedInformerFactory.WaitForCacheSync(stopCh) {
+	informersByStarted := make(map[bool][]string)
+	for informerType, started := range i.cacheSyncWaiter.WaitForCacheSync(stopCh) {
 		informersByStarted[started] = append(informersByStarted[started], informerType.String())
 	}
 

pkg/server/healthz/healthz_test.go

@@ -26,6 +26,7 @@ import (
 	"strings"
 	"testing"
 
+	corev1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/apiserver/pkg/endpoints/metrics"
 	"k8s.io/component-base/metrics/legacyregistry"
@@ -273,3 +274,43 @@ func createGetRequestWithUrl(rawUrlString string) *http.Request {
 		URL:    url,
 	}
 }
+
+func TestInformerSyncHealthChecker(t *testing.T) {
+	t.Run("test that check returns nil when all informers are started", func(t *testing.T) {
+		healthChecker := NewInformerSyncHealthz(cacheSyncWaiterStub{
+			startedByInformerType: map[reflect.Type]bool{
+				reflect.TypeOf(corev1.Pod{}): true,
+			},
+		})
+
+		err := healthChecker.Check(nil)
+		if err != nil {
+			t.Errorf("Got %v, expected no error", err)
+		}
+	})
+
+	t.Run("test that check returns err when there is not started informer", func(t *testing.T) {
+		healthChecker := NewInformerSyncHealthz(cacheSyncWaiterStub{
+			startedByInformerType: map[reflect.Type]bool{
+				reflect.TypeOf(corev1.Pod{}):     true,
+				reflect.TypeOf(corev1.Service{}): false,
+				reflect.TypeOf(corev1.Node{}):    true,
+			},
+		})
+
+		err := healthChecker.Check(nil)
+		if err == nil {
+			t.Errorf("expected error, got: %v", err)
+		}
+	})
+}
+
+type cacheSyncWaiterStub struct {
+	startedByInformerType map[reflect.Type]bool
+}
+
+// WaitForCacheSync is a stub implementation of the corresponding func
+// that simply returns the value passed during stub initialization.
+func (s cacheSyncWaiterStub) WaitForCacheSync(_ <-chan struct{}) map[reflect.Type]bool {
+	return s.startedByInformerType
+}