From f262560caca5db3fdf35014f67d494ddfad909c4 Mon Sep 17 00:00:00 2001
From: Solly Ross <sross@redhat.com>
Date: Mon, 2 Nov 2015 11:14:08 -0500
Subject: [PATCH] Customize HPA Heapster service namespace/name

This commit makes the HPA metrics client configurable in where
it looks for heapster instead of hard coding it to
"kube-system/heapster".  The values of "kube-system/heapster"
are still recorded as constants in the metrics client package
for use as default values.
---
 .../app/controllermanager.go                       |  3 ++-
 pkg/controller/podautoscaler/horizontal_test.go    |  3 ++-
 .../podautoscaler/metrics/metrics_client.go        | 14 +++++++++-----
 .../podautoscaler/metrics/metrics_client_test.go   |  2 +-
 4 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/cmd/kube-controller-manager/app/controllermanager.go b/cmd/kube-controller-manager/app/controllermanager.go
index 8b200f6bfd4..4cd4e89fd08 100644
--- a/cmd/kube-controller-manager/app/controllermanager.go
+++ b/cmd/kube-controller-manager/app/controllermanager.go
@@ -336,7 +336,8 @@ func (s *CMServer) Run(_ []string) error {
 		glog.Infof("Starting %s apis", groupVersion)
 		if containsResource(resources, "horizontalpodautoscalers") {
 			glog.Infof("Starting horizontal pod controller.")
-			podautoscaler.NewHorizontalController(kubeClient, metrics.NewHeapsterMetricsClient(kubeClient)).
+			metricsClient := metrics.NewHeapsterMetricsClient(kubeClient, metrics.DefaultHeapsterNamespace, metrics.DefaultHeapsterService)
+			podautoscaler.NewHorizontalController(kubeClient, metricsClient).
 				Run(s.HorizontalPodAutoscalerSyncPeriod)
 		}
 
diff --git a/pkg/controller/podautoscaler/horizontal_test.go b/pkg/controller/podautoscaler/horizontal_test.go
index 5f96de060f5..854bb53f814 100644
--- a/pkg/controller/podautoscaler/horizontal_test.go
+++ b/pkg/controller/podautoscaler/horizontal_test.go
@@ -206,7 +206,8 @@ func (tc *testCase) verifyResults(t *testing.T) {
 
 func (tc *testCase) runTest(t *testing.T) {
 	testClient := tc.prepareTestClient(t)
-	hpaController := NewHorizontalController(testClient, metrics.NewHeapsterMetricsClient(testClient))
+	metricsClient := metrics.NewHeapsterMetricsClient(testClient, metrics.DefaultHeapsterNamespace, metrics.DefaultHeapsterService)
+	hpaController := NewHorizontalController(testClient, metricsClient)
 	err := hpaController.reconcileAutoscalers()
 	assert.Equal(t, nil, err)
 	if tc.verifyEvents {
diff --git a/pkg/controller/podautoscaler/metrics/metrics_client.go b/pkg/controller/podautoscaler/metrics/metrics_client.go
index 13bb79c142c..dde980fbe69 100644
--- a/pkg/controller/podautoscaler/metrics/metrics_client.go
+++ b/pkg/controller/podautoscaler/metrics/metrics_client.go
@@ -33,8 +33,8 @@ import (
 )
 
 const (
-	heapsterNamespace = "kube-system"
-	heapsterService   = "heapster"
+	DefaultHeapsterNamespace = "kube-system"
+	DefaultHeapsterService   = "heapster"
 )
 
 var heapsterQueryStart = -5 * time.Minute
@@ -66,6 +66,8 @@ type metricDefinition struct {
 type HeapsterMetricsClient struct {
 	client              client.Interface
 	resourceDefinitions map[api.ResourceName]metricDefinition
+	heapsterNamespace   string
+	heapsterService     string
 }
 
 var heapsterMetricDefinitions = map[api.ResourceName]metricDefinition{
@@ -91,10 +93,12 @@ var heapsterMetricDefinitions = map[api.ResourceName]metricDefinition{
 }
 
 // NewHeapsterMetricsClient returns a new instance of Heapster-based implementation of MetricsClient interface.
-func NewHeapsterMetricsClient(client client.Interface) *HeapsterMetricsClient {
+func NewHeapsterMetricsClient(client client.Interface, namespace, service string) *HeapsterMetricsClient {
 	return &HeapsterMetricsClient{
 		client:              client,
 		resourceDefinitions: heapsterMetricDefinitions,
+		heapsterNamespace:   namespace,
+		heapsterService:     service,
 	}
 }
 
@@ -155,8 +159,8 @@ func (h *HeapsterMetricsClient) getForPods(resourceName api.ResourceName, namesp
 		strings.Join(podNames, ","),
 		metricSpec.name)
 
-	resultRaw, err := h.client.Services(heapsterNamespace).
-		ProxyGet(heapsterService, metricPath, map[string]string{"start": startTime.Format(time.RFC3339)}).
+	resultRaw, err := h.client.Services(h.heapsterNamespace).
+		ProxyGet(h.heapsterService, metricPath, map[string]string{"start": startTime.Format(time.RFC3339)}).
 		DoRaw()
 
 	if err != nil {
diff --git a/pkg/controller/podautoscaler/metrics/metrics_client_test.go b/pkg/controller/podautoscaler/metrics/metrics_client_test.go
index c1b4f994efb..8e7d99bfaa0 100644
--- a/pkg/controller/podautoscaler/metrics/metrics_client_test.go
+++ b/pkg/controller/podautoscaler/metrics/metrics_client_test.go
@@ -148,7 +148,7 @@ func (tc *testCase) verifyResults(t *testing.T, val *ResourceConsumption, err er
 
 func (tc *testCase) runTest(t *testing.T) {
 	testClient := tc.prepareTestClient(t)
-	metricsClient := NewHeapsterMetricsClient(testClient)
+	metricsClient := NewHeapsterMetricsClient(testClient, DefaultHeapsterNamespace, DefaultHeapsterService)
 	val, _, err := metricsClient.GetResourceConsumptionAndRequest(tc.targetResource, tc.namespace, tc.selector)
 	tc.verifyResults(t, val, err)
 }