From 3d4eccf3a7129b2db488402106ac7488f9997b3f Mon Sep 17 00:00:00 2001
From: Satish Matti <smatti@google.com>
Date: Thu, 15 Jun 2023 16:53:41 -0700
Subject: [PATCH] Use KUBECONFIG env for kuberenetes client if specified

Change-Id: I0ce80ee726d5e5864752a81a6bad946b89d5a6ec
---
 node/pkg/cni/token_watch.go             | 2 +-
 node/pkg/lifecycle/shutdown/shutdown.go | 4 ++--
 node/pkg/lifecycle/startup/startup.go   | 5 +++--
 3 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/node/pkg/cni/token_watch.go b/node/pkg/cni/token_watch.go
index 91915780b64..ad60157480c 100644
--- a/node/pkg/cni/token_watch.go
+++ b/node/pkg/cni/token_watch.go
@@ -222,7 +222,7 @@ func Run() {
 
 	for tu := range tokenChan {
 		logrus.Info("Update of CNI kubeconfig triggered based on elapsed time.")
-		cfg, err := rest.InClusterConfig()
+		cfg, err := clientcmd.BuildConfigFromFlags("", os.Getenv("KUBECONFIG"))
 		if err != nil {
 			logrus.WithError(err).Error("Error generating kube config.")
 			continue
diff --git a/node/pkg/lifecycle/shutdown/shutdown.go b/node/pkg/lifecycle/shutdown/shutdown.go
index 9b80525a70e..21a3fc06cd7 100644
--- a/node/pkg/lifecycle/shutdown/shutdown.go
+++ b/node/pkg/lifecycle/shutdown/shutdown.go
@@ -19,7 +19,7 @@ import (
 
 	log "github.com/sirupsen/logrus"
 	"k8s.io/client-go/kubernetes"
-	"k8s.io/client-go/rest"
+	"k8s.io/client-go/tools/clientcmd"
 
 	"github.com/projectcalico/calico/node/pkg/lifecycle/utils"
 )
@@ -43,7 +43,7 @@ func Run() {
 	var clientset *kubernetes.Clientset
 
 	// If running under kubernetes with secrets to call k8s API
-	if config, err := rest.InClusterConfig(); err == nil {
+	if config, err := clientcmd.BuildConfigFromFlags("", os.Getenv("KUBECONFIG")); err == nil {
 		// default timeout is 30 seconds, which isn't appropriate for this kind of
 		// shutdown action because network services, like kube-proxy might not be
 		// running and we don't want to block the full 30 seconds if they are just
diff --git a/node/pkg/lifecycle/startup/startup.go b/node/pkg/lifecycle/startup/startup.go
index 7d7e1c91784..45b4cb79acb 100644
--- a/node/pkg/lifecycle/startup/startup.go
+++ b/node/pkg/lifecycle/startup/startup.go
@@ -31,6 +31,7 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/rest"
+	"k8s.io/client-go/tools/clientcmd"
 
 	api "github.com/projectcalico/api/pkg/apis/projectcalico/v3"
 	"github.com/projectcalico/api/pkg/lib/numorstring"
@@ -129,7 +130,7 @@ func Run() {
 	}
 
 	// If running under kubernetes with secrets to call k8s API
-	if config, err := rest.InClusterConfig(); err == nil {
+	if config, err := clientcmd.BuildConfigFromFlags("", os.Getenv("KUBECONFIG")); err == nil {
 		// default timeout is 30 seconds, which isn't appropriate for this kind of
 		// startup action because network services, like kube-proxy might not be
 		// running and we don't want to block the full 30 seconds if they are just
@@ -329,7 +330,7 @@ func MonitorIPAddressSubnets() {
 	if nodeRef := os.Getenv("CALICO_K8S_NODE_REF"); nodeRef != "" {
 		k8sNodeName = nodeRef
 	}
-	if config, err = rest.InClusterConfig(); err == nil {
+	if config, err = clientcmd.BuildConfigFromFlags("", os.Getenv("KUBECONFIG")); err == nil {
 		// Create the k8s clientset.
 		clientset, err = kubernetes.NewForConfig(config)
 		if err != nil {