Refactor kubelet server into its own package

Refactor Kubelet's server functionality into a server package. Most
notably, move pkg/kubelet/server.go into
pkg/kubelet/server/server.go. This will lead to better separation of
concerns and a more readable code hierarchy.

cmd/kubelet/app/server.go

@@ -47,6 +47,7 @@ import (
 	"k8s.io/kubernetes/pkg/kubelet/dockertools"
 	"k8s.io/kubernetes/pkg/kubelet/network"
 	"k8s.io/kubernetes/pkg/kubelet/qos"
+	"k8s.io/kubernetes/pkg/kubelet/server"
 	kubetypes "k8s.io/kubernetes/pkg/kubelet/types"
 	"k8s.io/kubernetes/pkg/master/ports"
 	"k8s.io/kubernetes/pkg/util"
@@ -162,7 +163,7 @@ type KubeletServer struct {
 type KubeletBootstrap interface {
 	BirthCry()
 	StartGarbageCollection()
-	ListenAndServe(address net.IP, port uint, tlsOptions *kubelet.TLSOptions, auth kubelet.AuthInterface, enableDebuggingHandlers bool)
+	ListenAndServe(address net.IP, port uint, tlsOptions *server.TLSOptions, auth server.AuthInterface, enableDebuggingHandlers bool)
 	ListenAndServeReadOnly(address net.IP, port uint)
 	Run(<-chan kubetypes.PodUpdate)
 	RunOnce(<-chan kubetypes.PodUpdate) ([]kubelet.RunPodResult, error)
@@ -572,8 +573,8 @@ func (s *KubeletServer) Run(kcfg *KubeletConfig) error {
 }
 
 // InitializeTLS checks for a configured TLSCertFile and TLSPrivateKeyFile: if unspecified a new self-signed
-// certificate and key file are generated. Returns a configured kubelet.TLSOptions object.
-func (s *KubeletServer) InitializeTLS() (*kubelet.TLSOptions, error) {
+// certificate and key file are generated. Returns a configured server.TLSOptions object.
+func (s *KubeletServer) InitializeTLS() (*server.TLSOptions, error) {
 	if s.TLSCertFile == "" && s.TLSPrivateKeyFile == "" {
 		s.TLSCertFile = path.Join(s.CertDirectory, "kubelet.crt")
 		s.TLSPrivateKeyFile = path.Join(s.CertDirectory, "kubelet.key")
@@ -582,7 +583,7 @@ func (s *KubeletServer) InitializeTLS() (*kubelet.TLSOptions, error) {
 		}
 		glog.V(4).Infof("Using self-signed cert (%s, %s)", s.TLSCertFile, s.TLSPrivateKeyFile)
 	}
-	tlsOptions := &kubelet.TLSOptions{
+	tlsOptions := &server.TLSOptions{
 		Config: &tls.Config{
 			// Change default from SSLv3 to TLSv1.0 (because of POODLE vulnerability).
 			MinVersion: tls.VersionTLS10,
@@ -694,7 +695,7 @@ func SimpleKubelet(client *client.Client,
 	readOnlyPort uint,
 	masterServiceNamespace string,
 	volumePlugins []volume.VolumePlugin,
-	tlsOptions *kubelet.TLSOptions,
+	tlsOptions *server.TLSOptions,
 	cadvisorInterface cadvisor.Interface,
 	configFilePath string,
 	cloud cloudprovider.Interface,
@@ -884,7 +885,7 @@ func makePodSourceConfig(kc *KubeletConfig) *config.PodConfig {
 type KubeletConfig struct {
 	Address                        net.IP
 	AllowPrivileged                bool
-	Auth                           kubelet.AuthInterface
+	Auth                           server.AuthInterface
 	Builder                        KubeletBuilder
 	CAdvisorInterface              cadvisor.Interface
 	CgroupRoot                     string
@@ -955,7 +956,7 @@ type KubeletConfig struct {
 	StreamingConnectionIdleTimeout time.Duration
 	SyncFrequency                  time.Duration
 	SystemContainer                string
-	TLSOptions                     *kubelet.TLSOptions
+	TLSOptions                     *server.TLSOptions
 	Writer                         io.Writer
 	VolumePlugins                  []volume.VolumePlugin
 

pkg/client/unversioned/portforward/portforward.go

@@ -29,7 +29,7 @@ import (
 
 	"github.com/golang/glog"
 	"k8s.io/kubernetes/pkg/api"
-	"k8s.io/kubernetes/pkg/kubelet/portforward"
+	"k8s.io/kubernetes/pkg/kubelet/server/portforward"
 	"k8s.io/kubernetes/pkg/util"
 	"k8s.io/kubernetes/pkg/util/httpstream"
 )

pkg/client/unversioned/portforward/portforward_test.go

@@ -32,7 +32,7 @@ import (
 
 	client "k8s.io/kubernetes/pkg/client/unversioned"
 	"k8s.io/kubernetes/pkg/client/unversioned/remotecommand"
-	"k8s.io/kubernetes/pkg/kubelet"
+	kubeletserver "k8s.io/kubernetes/pkg/kubelet/server"
 	"k8s.io/kubernetes/pkg/types"
 	"k8s.io/kubernetes/pkg/util/httpstream"
 )
@@ -204,7 +204,7 @@ func TestGetListener(t *testing.T) {
 }
 
 // fakePortForwarder simulates port forwarding for testing. It implements
-// kubelet.PortForwarder.
+// kubeletserver.PortForwarder.
 type fakePortForwarder struct {
 	lock sync.Mutex
 	// stores data expected from the stream per port
@@ -215,7 +215,7 @@ type fakePortForwarder struct {
 	send map[uint16]string
 }
 
-var _ kubelet.PortForwarder = &fakePortForwarder{}
+var _ kubeletserver.PortForwarder = &fakePortForwarder{}
 
 func (pf *fakePortForwarder) PortForward(name string, uid types.UID, port uint16, stream io.ReadWriteCloser) error {
 	defer stream.Close()
@@ -250,7 +250,7 @@ func fakePortForwardServer(t *testing.T, testName string, serverSends, expectedF
 			received: make(map[uint16]string),
 			send:     serverSends,
 		}
-		kubelet.ServePortForward(w, req, pf, "pod", "uid", 0, 10*time.Second)
+		kubeletserver.ServePortForward(w, req, pf, "pod", "uid", 0, 10*time.Second)
 
 		for port, expected := range expectedFromClient {
 			actual, ok := pf.received[port]

pkg/kubelet/container/runtime.go

@@ -47,6 +47,10 @@ var (
 	// Required Image is absent on host and PullPolicy is NeverPullImage
 	ErrImageNeverPull = errors.New("ErrImageNeverPull")
 
+	// ErrContainerNotFound returned when a container in the given pod with the
+	// given container name was not found, amongst those managed by the kubelet.
+	ErrContainerNotFound = errors.New("no matching container")
+
 	// Get http error when pulling image from registry
 	RegistryUnavailable = errors.New("RegistryUnavailable")
 )

pkg/kubelet/kubelet.go

@@ -58,6 +58,7 @@ import (
 	"k8s.io/kubernetes/pkg/kubelet/prober"
 	proberesults "k8s.io/kubernetes/pkg/kubelet/prober/results"
 	"k8s.io/kubernetes/pkg/kubelet/rkt"
+	"k8s.io/kubernetes/pkg/kubelet/server"
 	"k8s.io/kubernetes/pkg/kubelet/status"
 	kubetypes "k8s.io/kubernetes/pkg/kubelet/types"
 	"k8s.io/kubernetes/pkg/kubelet/util/format"
@@ -127,12 +128,6 @@ const (
 	backOffPeriod = time.Second * 10
 )
 
-var (
-	// ErrContainerNotFound returned when a container in the given pod with the
-	// given container name was not found, amongst those managed by the kubelet.
-	ErrContainerNotFound = errors.New("no matching container")
-)
-
 // SyncHandler is an interface implemented by Kubelet, for testability
 type SyncHandler interface {
 	HandlePodAdditions(pods []*api.Pod)
@@ -3215,7 +3210,7 @@ func (kl *Kubelet) GetContainerInfo(podFullName string, podUID types.UID, contai
 	pod := kubecontainer.Pods(pods).FindPod(podFullName, podUID)
 	container := pod.FindContainerByName(containerName)
 	if container == nil {
-		return nil, ErrContainerNotFound
+		return nil, kubecontainer.ErrContainerNotFound
 	}
 
 	ci, err := kl.cadvisor.DockerContainer(container.ID.ID, req)
@@ -3252,12 +3247,12 @@ func (kl *Kubelet) GetCachedMachineInfo() (*cadvisorapi.MachineInfo, error) {
 	return kl.machineInfo, nil
 }
 
-func (kl *Kubelet) ListenAndServe(address net.IP, port uint, tlsOptions *TLSOptions, auth AuthInterface, enableDebuggingHandlers bool) {
-	ListenAndServeKubeletServer(kl, address, port, tlsOptions, auth, enableDebuggingHandlers)
+func (kl *Kubelet) ListenAndServe(address net.IP, port uint, tlsOptions *server.TLSOptions, auth server.AuthInterface, enableDebuggingHandlers bool) {
+	server.ListenAndServeKubeletServer(kl, address, port, tlsOptions, auth, enableDebuggingHandlers)
 }
 
 func (kl *Kubelet) ListenAndServeReadOnly(address net.IP, port uint) {
-	ListenAndServeKubeletReadOnlyServer(kl, address, port)
+	server.ListenAndServeKubeletReadOnlyServer(kl, address, port)
 }
 
 // GetRuntime returns the current Runtime implementation in use by the kubelet. This func

pkg/kubelet/kubelet_test.go

@@ -778,8 +778,8 @@ func TestGetContainerInfoWithNoContainers(t *testing.T) {
 	if err == nil {
 		t.Errorf("expected error from cadvisor client, got none")
 	}
-	if err != ErrContainerNotFound {
-		t.Errorf("expected error %v, got %v", ErrContainerNotFound.Error(), err.Error())
+	if err != kubecontainer.ErrContainerNotFound {
+		t.Errorf("expected error %v, got %v", kubecontainer.ErrContainerNotFound.Error(), err.Error())
 	}
 	if stats != nil {
 		t.Errorf("non-nil stats when dockertools returned no containers")
@@ -808,8 +808,8 @@ func TestGetContainerInfoWithNoMatchingContainers(t *testing.T) {
 	if err == nil {
 		t.Errorf("Expected error from cadvisor client, got none")
 	}
-	if err != ErrContainerNotFound {
-		t.Errorf("Expected error %v, got %v", ErrContainerNotFound.Error(), err.Error())
+	if err != kubecontainer.ErrContainerNotFound {
+		t.Errorf("Expected error %v, got %v", kubecontainer.ErrContainerNotFound.Error(), err.Error())
 	}
 	if stats != nil {
 		t.Errorf("non-nil stats when dockertools returned no containers")

pkg/kubelet/server/auth.go

@@ -14,7 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-package kubelet
+package server
 
 import (
 	"k8s.io/kubernetes/pkg/auth/authenticator"

pkg/kubelet/server/doc.go

@@ -0,0 +1,18 @@
+/*
+Copyright 2014 The Kubernetes Authors All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package server contains functions related to serving Kubelet's external interface.
+package server

pkg/kubelet/server/server.go

@@ -14,7 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-package kubelet
+package server
 
 import (
 	"crypto/tls"
@@ -48,7 +48,7 @@ import (
 	"k8s.io/kubernetes/pkg/healthz"
 	"k8s.io/kubernetes/pkg/httplog"
 	kubecontainer "k8s.io/kubernetes/pkg/kubelet/container"
-	"k8s.io/kubernetes/pkg/kubelet/portforward"
+	"k8s.io/kubernetes/pkg/kubelet/server/portforward"
 	"k8s.io/kubernetes/pkg/types"
 	"k8s.io/kubernetes/pkg/util"
 	"k8s.io/kubernetes/pkg/util/flushwriter"
@@ -1146,7 +1146,7 @@ func (s *Server) serveStats(w http.ResponseWriter, req *http.Request) {
 	switch err {
 	case nil:
 		break
-	case ErrContainerNotFound:
+	case kubecontainer.ErrContainerNotFound:
 		http.Error(w, err.Error(), http.StatusNotFound)
 		return
 	default:

pkg/kubelet/server/server_test.go

@@ -14,7 +14,7 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-package kubelet
+package server
 
 import (
 	"bytes"
@@ -38,6 +38,7 @@ import (
 	apierrs "k8s.io/kubernetes/pkg/api/errors"
 	"k8s.io/kubernetes/pkg/auth/authorizer"
 	"k8s.io/kubernetes/pkg/auth/user"
+	kubecontainer "k8s.io/kubernetes/pkg/kubelet/container"
 	kubetypes "k8s.io/kubernetes/pkg/kubelet/types"
 	"k8s.io/kubernetes/pkg/types"
 	"k8s.io/kubernetes/pkg/util/httpstream"
@@ -271,7 +272,7 @@ func TestContainerNotFound(t *testing.T) {
 	expectedContainerName := "slowstartcontainer"
 	expectedUid := "9b01b80f-8fb4-11e4-95ab-4200af06647"
 	fw.fakeKubelet.containerInfoFunc = func(podID string, uid types.UID, containerName string, req *cadvisorapi.ContainerInfoRequest) (*cadvisorapi.ContainerInfo, error) {
-		return nil, ErrContainerNotFound
+		return nil, kubecontainer.ErrContainerNotFound
 	}
 	resp, err := http.Get(fw.testHTTPServer.URL + fmt.Sprintf("/stats/%v/%v/%v/%v", expectedNamespace, podID, expectedUid, expectedContainerName))
 	if err != nil {

test/e2e/kubelet_stats.go

@@ -34,8 +34,8 @@ import (
 	"github.com/prometheus/common/model"
 	"k8s.io/kubernetes/pkg/api"
 	client "k8s.io/kubernetes/pkg/client/unversioned"
-	"k8s.io/kubernetes/pkg/kubelet"
 	"k8s.io/kubernetes/pkg/kubelet/metrics"
+	"k8s.io/kubernetes/pkg/kubelet/server"
 	"k8s.io/kubernetes/pkg/master/ports"
 	"k8s.io/kubernetes/pkg/util"
 	"k8s.io/kubernetes/pkg/util/sets"
@@ -150,7 +150,7 @@ func HighLatencyKubeletOperations(c *client.Client, threshold time.Duration, nod
 
 // getContainerInfo contacts kubelet for the container information. The "Stats"
 // in the returned ContainerInfo is subject to the requirements in statsRequest.
-func getContainerInfo(c *client.Client, nodeName string, req *kubelet.StatsRequest) (map[string]cadvisorapi.ContainerInfo, error) {
+func getContainerInfo(c *client.Client, nodeName string, req *server.StatsRequest) (map[string]cadvisorapi.ContainerInfo, error) {
 	reqBody, err := json.Marshal(req)
 	if err != nil {
 		return nil, err
@@ -243,7 +243,7 @@ func getOneTimeResourceUsageOnNode(
 		return nil, fmt.Errorf("numStats needs to be > 1 and < %d", maxNumStatsToRequest)
 	}
 	// Get information of all containers on the node.
-	containerInfos, err := getContainerInfo(c, nodeName, &kubelet.StatsRequest{
+	containerInfos, err := getContainerInfo(c, nodeName, &server.StatsRequest{
 		ContainerName: "/",
 		NumStats:      numStats,
 		Subcontainers: true,
@@ -590,7 +590,7 @@ func (r *resourceCollector) Stop() {
 // collectStats gets the latest stats from kubelet's /stats/container, computes
 // the resource usage, and pushes it to the buffer.
 func (r *resourceCollector) collectStats(oldStats map[string]*cadvisorapi.ContainerStats) {
-	infos, err := getContainerInfo(r.client, r.node, &kubelet.StatsRequest{
+	infos, err := getContainerInfo(r.client, r.node, &server.StatsRequest{
 		ContainerName: "/",
 		NumStats:      1,
 		Subcontainers: true,