From 493ac4f65e0924be669cc0b986f92902129686f4 Mon Sep 17 00:00:00 2001
From: hxcGit <houxc_mail@163.com>
Date: Thu, 29 Sep 2022 15:55:13 +0800
Subject: [PATCH] use local cache to get pods

Signed-off-by: hxcGit <houxc_mail@163.com>
---
 pkg/yurthub/otaupdate/ota.go      | 27 +++++++++++++++++++--------
 pkg/yurthub/otaupdate/ota_test.go |  8 +++++++-
 pkg/yurthub/server/server.go      |  2 +-
 3 files changed, 27 insertions(+), 10 deletions(-)

diff --git a/pkg/yurthub/otaupdate/ota.go b/pkg/yurthub/otaupdate/ota.go
index 32227738b3e..679e04fa8d9 100644
--- a/pkg/yurthub/otaupdate/ota.go
+++ b/pkg/yurthub/otaupdate/ota.go
@@ -24,10 +24,12 @@ import (
 	"github.com/gorilla/mux"
 	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/labels"
 	"k8s.io/apimachinery/pkg/runtime"
 	runtimescheme "k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/kubernetes/scheme"
+	corelisters "k8s.io/client-go/listers/core/v1"
 	"k8s.io/klog/v2"
 
 	"github.com/openyurtio/openyurt/pkg/controller/daemonpodupdater"
@@ -37,20 +39,24 @@ import (
 type OTAHandler func(kubernetes.Interface, string) http.Handler
 
 // GetPods return pod list
-func GetPods(clientset kubernetes.Interface, nodeName string) http.Handler {
+func GetPods(podLister corelisters.PodLister, nodeName string) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		podList, err := clientset.CoreV1().Pods("").List(context.TODO(), metav1.ListOptions{
-			FieldSelector: fmt.Sprintf("spec.nodeName=%s", nodeName),
-		})
+		pods, err := podLister.Pods("").List(labels.Everything())
 		if err != nil {
 			klog.Errorf("Get pod list failed, %v", err)
 			WriteErr(w, "Get pod list failed", http.StatusInternalServerError)
 			return
 		}
-		klog.V(5).Infof("Got pod list: %v", podList)
+
+		var otaPods []*corev1.Pod
+		for _, pod := range pods {
+			if pod.Spec.NodeName == nodeName {
+				otaPods = append(otaPods, pod)
+			}
+		}
 
 		// Successfully get pod list, response 200
-		data, err := encodePodList(podList)
+		data, err := encodePods(otaPods)
 		if err != nil {
 			klog.Errorf("Encode pod list failed, %v", err)
 			WriteErr(w, "Encode pod list failed", http.StatusInternalServerError)
@@ -120,8 +126,13 @@ func applyUpdate(clientset kubernetes.Interface, namespace, podName, nodeName st
 	return nil, true
 }
 
-// encodePodList returns the encoded PodList
-func encodePodList(podList *corev1.PodList) ([]byte, error) {
+// Derived from kubelet encodePods
+func encodePods(pods []*corev1.Pod) (data []byte, err error) {
+	podList := new(corev1.PodList)
+	for _, pod := range pods {
+		podList.Items = append(podList.Items, *pod)
+	}
+
 	codec := scheme.Codecs.LegacyCodec(runtimescheme.GroupVersion{Group: corev1.GroupName, Version: "v1"})
 	return runtime.Encode(codec, podList)
 }
diff --git a/pkg/yurthub/otaupdate/ota_test.go b/pkg/yurthub/otaupdate/ota_test.go
index 71ddd0ba8f3..38cd92762bf 100644
--- a/pkg/yurthub/otaupdate/ota_test.go
+++ b/pkg/yurthub/otaupdate/ota_test.go
@@ -25,6 +25,7 @@ import (
 	"github.com/stretchr/testify/assert"
 	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/client-go/informers"
 	"k8s.io/client-go/kubernetes/fake"
 
 	"github.com/openyurtio/openyurt/pkg/controller/daemonpodupdater"
@@ -66,6 +67,11 @@ func TestGetPods(t *testing.T) {
 	normalPod := newPod("normalPod")
 
 	clientset := fake.NewSimpleClientset(updatablePod, notUpdatablePod, normalPod)
+	podInformer := informers.NewSharedInformerFactory(clientset, 0).Core().V1().Pods()
+
+	podInformer.Informer().GetStore().Add(updatablePod)
+	podInformer.Informer().GetStore().Add(notUpdatablePod)
+	podInformer.Informer().GetStore().Add(normalPod)
 
 	req, err := http.NewRequest("GET", "/openyurt.io/v1/pods", nil)
 	if err != nil {
@@ -73,7 +79,7 @@ func TestGetPods(t *testing.T) {
 	}
 	rr := httptest.NewRecorder()
 
-	GetPods(clientset, "").ServeHTTP(rr, req)
+	GetPods(podInformer.Lister(), "").ServeHTTP(rr, req)
 
 	expectedCode := http.StatusOK
 	assert.Equal(t, expectedCode, rr.Code)
diff --git a/pkg/yurthub/server/server.go b/pkg/yurthub/server/server.go
index 7da09cbd23a..1530815bfcf 100644
--- a/pkg/yurthub/server/server.go
+++ b/pkg/yurthub/server/server.go
@@ -174,7 +174,7 @@ func registerHandlers(c *mux.Router, cfg *config.YurtHubConfiguration, certifica
 	c.Handle("/metrics", promhttp.Handler())
 
 	// register handler for ota upgrade
-	c.Handle("/pods", ota.HealthyCheck(rest, cfg.NodeName, ota.GetPods)).Methods("GET")
+	c.Handle("/pods", ota.GetPods(cfg.SharedFactory.Core().V1().Pods().Lister(), cfg.NodeName)).Methods("GET")
 	c.Handle("/openyurt.io/v1/namespaces/{ns}/pods/{podname}/upgrade",
 		ota.HealthyCheck(rest, cfg.NodeName, ota.UpdatePod)).Methods("POST")
 }