From 916cd530f6b4c992d16f571933fe128ed299453b Mon Sep 17 00:00:00 2001
From: rajat-0 <amrahstajar@gmail.com>
Date: Wed, 30 Jan 2019 00:29:11 +0000
Subject: [PATCH] Allow vpa-admission-controler to installl on specific path

---
 .../pkg/admission-controller/config.go         | 18 ++++++++++--------
 .../pkg/admission-controller/main.go           | 11 ++++++++---
 2 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/vertical-pod-autoscaler/pkg/admission-controller/config.go b/vertical-pod-autoscaler/pkg/admission-controller/config.go
index c1f88ae5d70..c831078b1c3 100644
--- a/vertical-pod-autoscaler/pkg/admission-controller/config.go
+++ b/vertical-pod-autoscaler/pkg/admission-controller/config.go
@@ -82,7 +82,7 @@ func configTLS(clientset *kubernetes.Clientset, serverCert, serverKey []byte) *t
 
 // register this webhook admission controller with the kube-apiserver
 // by creating MutatingWebhookConfiguration.
-func selfRegistration(clientset *kubernetes.Clientset, caCert []byte, namespace *string) {
+func selfRegistration(clientset *kubernetes.Clientset, caCert []byte, namespace *string, url string, registerByURL bool) {
 	time.Sleep(10 * time.Second)
 	client := clientset.AdmissionregistrationV1beta1().MutatingWebhookConfigurations()
 	_, err := client.Get(webhookConfigName, metav1.GetOptions{})
@@ -91,6 +91,14 @@ func selfRegistration(clientset *kubernetes.Clientset, caCert []byte, namespace
 			glog.Fatal(err2)
 		}
 	}
+	RegisterClientConfig := v1beta1.WebhookClientConfig{}
+	if !registerByURL {
+		RegisterClientConfig.Service.Name = *namespace
+		RegisterClientConfig.Service.Name = "vpa-webhook"
+	} else {
+		RegisterClientConfig.URL = url
+	}
+	RegisterClientConfig.CABundle = caCert
 	webhookConfig := &v1beta1.MutatingWebhookConfiguration{
 		ObjectMeta: metav1.ObjectMeta{
 			Name: webhookConfigName,
@@ -115,13 +123,7 @@ func selfRegistration(clientset *kubernetes.Clientset, caCert []byte, namespace
 							Resources:   []string{"verticalpodautoscalers"},
 						},
 					}},
-				ClientConfig: v1beta1.WebhookClientConfig{
-					Service: &v1beta1.ServiceReference{
-						Namespace: *namespace,
-						Name:      "vpa-webhook",
-					},
-					CABundle: caCert,
-				},
+				ClientConfig: RegisterClientConfig,
 			},
 		},
 	}
diff --git a/vertical-pod-autoscaler/pkg/admission-controller/main.go b/vertical-pod-autoscaler/pkg/admission-controller/main.go
index d244cf60edf..1f01fca1626 100644
--- a/vertical-pod-autoscaler/pkg/admission-controller/main.go
+++ b/vertical-pod-autoscaler/pkg/admission-controller/main.go
@@ -18,6 +18,7 @@ package main
 
 import (
 	"flag"
+	"fmt"
 	"net/http"
 	"os"
 	"time"
@@ -41,8 +42,11 @@ var (
 		tlsPrivateKey: flag.String("tls-private-key", "/etc/tls-certs/serverKey.pem", "Path to server certificate key PEM file."),
 	}
 
-	address   = flag.String("address", ":8944", "The address to expose Prometheus metrics.")
-	namespace = os.Getenv("NAMESPACE")
+	address        = flag.String("address", ":8944", "The address to expose Prometheus metrics.")
+	namespace      = os.Getenv("NAMESPACE")
+	webhookAddress = flag.String("webhookHostName", "", "Address under which webhook is registered. Used when registerByURL is set to true.")
+	webhookPort    = flag.String("Server Port", "", "Server Port for Webhook")
+	registerByURL  = flag.Bool("registerByURL", false, "If set to true, admission webhook will be registered by URL (webhookAddress:webhookPort) instead of by service name")
 )
 
 func newReadyVPALister(stopChannel <-chan struct{}) vpa_lister.VerticalPodAutoscalerLister {
@@ -75,6 +79,7 @@ func main() {
 		Addr:      ":8000",
 		TLSConfig: configTLS(clientset, certs.serverCert, certs.serverKey),
 	}
-	go selfRegistration(clientset, certs.caCert, &namespace)
+	url := fmt.Sprintf("%v:%v", webhookAddress, webhookPort)
+	go selfRegistration(clientset, certs.caCert, &namespace, url, *registerByURL)
 	server.ListenAndServeTLS("", "")
 }