Merge pull request #19357 from timstclair/stats-refactor

pkg/kubelet/server/server.go

@@ -18,14 +18,12 @@ package server
 
 import (
 	"crypto/tls"
-	"encoding/json"
 	"errors"
 	"fmt"
 	"io"
 	"net"
 	"net/http"
 	"net/http/pprof"
-	"path"
 	"strconv"
 	"strings"
 	"sync"
@@ -49,6 +47,7 @@ import (
 	"k8s.io/kubernetes/pkg/httplog"
 	kubecontainer "k8s.io/kubernetes/pkg/kubelet/container"
 	"k8s.io/kubernetes/pkg/kubelet/server/portforward"
+	"k8s.io/kubernetes/pkg/kubelet/server/stats"
 	"k8s.io/kubernetes/pkg/types"
 	"k8s.io/kubernetes/pkg/util"
 	"k8s.io/kubernetes/pkg/util/flushwriter"
@@ -222,7 +221,7 @@ func (s *Server) InstallDefaultHandlers() {
 		Operation("getPods"))
 	s.restfulCont.Add(ws)
 
-	s.restfulCont.Handle("/stats/", &httpHandler{f: s.handleStats})
+	s.restfulCont.Add(stats.CreateHandlers(s.host))
 	s.restfulCont.Handle("/metrics", prometheus.Handler())
 
 	ws = new(restful.WebService)
@@ -357,13 +356,6 @@ func (h *httpHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	h.f(w, r)
 }
 
-// error serializes an error object into an HTTP response.
-func (s *Server) error(w http.ResponseWriter, err error) {
-	msg := fmt.Sprintf("Internal Error: %v", err)
-	glog.Infof("HTTP InternalServerError: %s", msg)
-	http.Error(w, msg, http.StatusInternalServerError)
-}
-
 // Checks if kubelet's sync loop  that updates containers is working.
 func (s *Server) syncLoopHealthCheck(req *http.Request) error {
 	duration := s.host.ResyncInterval() * 2
@@ -501,11 +493,6 @@ func (s *Server) getRunningPods(request *restful.Request, response *restful.Resp
 	response.Write(data)
 }
 
-// handleStats handles stats requests against the Kubelet.
-func (s *Server) handleStats(w http.ResponseWriter, req *http.Request) {
-	s.serveStats(w, req)
-}
-
 // getLogs handles logs requests against the Kubelet.
 func (s *Server) getLogs(request *restful.Request, response *restful.Response) {
 	s.host.ServeLogs(response, request.Request)
@@ -1061,107 +1048,3 @@ func (s *Server) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 	).Log()
 	s.restfulCont.ServeHTTP(w, req)
 }
-
-type StatsRequest struct {
-	// The name of the container for which to request stats.
-	// Default: /
-	ContainerName string `json:"containerName,omitempty"`
-
-	// Max number of stats to return.
-	// If start and end time are specified this limit is ignored.
-	// Default: 60
-	NumStats int `json:"num_stats,omitempty"`
-
-	// Start time for which to query information.
-	// If omitted, the beginning of time is assumed.
-	Start time.Time `json:"start,omitempty"`
-
-	// End time for which to query information.
-	// If omitted, current time is assumed.
-	End time.Time `json:"end,omitempty"`
-
-	// Whether to also include information from subcontainers.
-	// Default: false.
-	Subcontainers bool `json:"subcontainers,omitempty"`
-}
-
-// serveStats implements stats logic.
-func (s *Server) serveStats(w http.ResponseWriter, req *http.Request) {
-	// Stats requests are in the following forms:
-	//
-	// /stats/                                              : Root container stats
-	// /stats/container/                                    : Non-Kubernetes container stats (returns a map)
-	// /stats/<pod name>/<container name>                   : Stats for Kubernetes pod/container
-	// /stats/<namespace>/<pod name>/<uid>/<container name> : Stats for Kubernetes namespace/pod/uid/container
-	components := strings.Split(strings.TrimPrefix(path.Clean(req.URL.Path), "/"), "/")
-	var stats interface{}
-	var err error
-	var query StatsRequest
-	query.NumStats = 60
-
-	err = json.NewDecoder(req.Body).Decode(&query)
-	if err != nil && err != io.EOF {
-		s.error(w, err)
-		return
-	}
-	cadvisorRequest := cadvisorapi.ContainerInfoRequest{
-		NumStats: query.NumStats,
-		Start:    query.Start,
-		End:      query.End,
-	}
-
-	switch len(components) {
-	case 1:
-		// Root container stats.
-		var statsMap map[string]*cadvisorapi.ContainerInfo
-		statsMap, err = s.host.GetRawContainerInfo("/", &cadvisorRequest, false)
-		stats = statsMap["/"]
-	case 2:
-		// Non-Kubernetes container stats.
-		if components[1] != "container" {
-			http.Error(w, fmt.Sprintf("unknown stats request type %q", components[1]), http.StatusNotFound)
-			return
-		}
-		containerName := path.Join("/", query.ContainerName)
-		stats, err = s.host.GetRawContainerInfo(containerName, &cadvisorRequest, query.Subcontainers)
-	case 3:
-		// Backward compatibility without uid information, does not support namespace
-		pod, ok := s.host.GetPodByName(api.NamespaceDefault, components[1])
-		if !ok {
-			http.Error(w, "Pod does not exist", http.StatusNotFound)
-			return
-		}
-		stats, err = s.host.GetContainerInfo(kubecontainer.GetPodFullName(pod), "", components[2], &cadvisorRequest)
-	case 5:
-		pod, ok := s.host.GetPodByName(components[1], components[2])
-		if !ok {
-			http.Error(w, "Pod does not exist", http.StatusNotFound)
-			return
-		}
-		stats, err = s.host.GetContainerInfo(kubecontainer.GetPodFullName(pod), types.UID(components[3]), components[4], &cadvisorRequest)
-	default:
-		http.Error(w, fmt.Sprintf("Unknown resource: %v", components), http.StatusNotFound)
-		return
-	}
-	switch err {
-	case nil:
-		break
-	case kubecontainer.ErrContainerNotFound:
-		http.Error(w, err.Error(), http.StatusNotFound)
-		return
-	default:
-		s.error(w, err)
-		return
-	}
-	if stats == nil {
-		fmt.Fprint(w, "{}")
-		return
-	}
-	data, err := json.Marshal(stats)
-	if err != nil {
-		s.error(w, err)
-		return
-	}
-	w.Header().Add("Content-type", "application/json")
-	w.Write(data)
-}

pkg/kubelet/server/server_test.go

@@ -534,7 +534,7 @@ func TestAuthFilters(t *testing.T) {
 
 	// This is a sanity check that the Handle->HandleWithFilter() delegation is working
 	// Ideally, these would move to registered web services and this list would get shorter
-	expectedPaths := []string{"/healthz", "/stats/", "/metrics"}
+	expectedPaths := []string{"/healthz", "/metrics"}
 	paths := sets.NewString(fw.serverUnderTest.restfulCont.RegisteredHandlePaths()...)
 	for _, expectedPath := range expectedPaths {
 		if !paths.Has(expectedPath) {

pkg/kubelet/server/stats/handler.go

+/*
+Copyright 2016 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 stats
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"path"
+	"time"
+
+	"github.com/emicklei/go-restful"
+	"github.com/golang/glog"
+	cadvisorapi "github.com/google/cadvisor/info/v1"
+
+	"k8s.io/kubernetes/pkg/api"
+	kubecontainer "k8s.io/kubernetes/pkg/kubelet/container"
+	"k8s.io/kubernetes/pkg/types"
+)
+
+// Host methods required by stats handlers.
+type StatsProvider interface {
+	GetContainerInfo(podFullName string, uid types.UID, containerName string, req *cadvisorapi.ContainerInfoRequest) (*cadvisorapi.ContainerInfo, error)
+	GetRawContainerInfo(containerName string, req *cadvisorapi.ContainerInfoRequest, subcontainers bool) (map[string]*cadvisorapi.ContainerInfo, error)
+	GetPodByName(namespace, name string) (*api.Pod, bool)
+}
+
+type handler struct {
+	provider StatsProvider
+}
+
+func CreateHandlers(provider StatsProvider) *restful.WebService {
+	h := &handler{provider}
+
+	ws := &restful.WebService{}
+	ws.Path("/stats/").
+		Produces(restful.MIME_JSON)
+
+	endpoints := []struct {
+		path    string
+		handler restful.RouteFunction
+	}{
+		{"", h.handleStats},
+		{"/container", h.handleSystemContainer},
+		{"/{podName}/{containerName}", h.handlePodContainer},
+		{"/{namespace}/{podName}/{uid}/{containerName}", h.handlePodContainer},
+	}
+
+	for _, e := range endpoints {
+		for _, method := range []string{"GET", "POST"} {
+			ws.Route(ws.
+				Method(method).
+				Path(e.path).
+				To(e.handler))
+		}
+	}
+
+	return ws
+}
+
+type StatsRequest struct {
+	// The name of the container for which to request stats.
+	// Default: /
+	ContainerName string `json:"containerName,omitempty"`
+
+	// Max number of stats to return.
+	// If start and end time are specified this limit is ignored.
+	// Default: 60
+	NumStats int `json:"num_stats,omitempty"`
+
+	// Start time for which to query information.
+	// If omitted, the beginning of time is assumed.
+	Start time.Time `json:"start,omitempty"`
+
+	// End time for which to query information.
+	// If omitted, current time is assumed.
+	End time.Time `json:"end,omitempty"`
+
+	// Whether to also include information from subcontainers.
+	// Default: false.
+	Subcontainers bool `json:"subcontainers,omitempty"`
+}
+
+func (r *StatsRequest) cadvisorRequest() *cadvisorapi.ContainerInfoRequest {
+	return &cadvisorapi.ContainerInfoRequest{
+		NumStats: r.NumStats,
+		Start:    r.Start,
+		End:      r.End,
+	}
+}
+
+func parseStatsRequest(request *restful.Request) (StatsRequest, error) {
+	// Default request.
+	query := StatsRequest{
+		NumStats: 60,
+	}
+
+	err := json.NewDecoder(request.Request.Body).Decode(&query)
+	if err != nil && err != io.EOF {
+		return query, err
+	}
+	return query, nil
+}
+
+// Handles root container stats requests to /stats
+func (h *handler) handleStats(request *restful.Request, response *restful.Response) {
+	query, err := parseStatsRequest(request)
+	if err != nil {
+		handleError(response, err)
+		return
+	}
+
+	// Root container stats.
+	statsMap, err := h.provider.GetRawContainerInfo("/", query.cadvisorRequest(), false)
+	if err != nil {
+		handleError(response, err)
+		return
+	}
+	writeResponse(response, statsMap["/"])
+}
+
+// Handles non-kubernetes container stats requests to /stats/container/
+func (h *handler) handleSystemContainer(request *restful.Request, response *restful.Response) {
+	query, err := parseStatsRequest(request)
+	if err != nil {
+		handleError(response, err)
+		return
+	}
+
+	// Non-Kubernetes container stats.
+	containerName := path.Join("/", query.ContainerName)
+	stats, err := h.provider.GetRawContainerInfo(
+		containerName, query.cadvisorRequest(), query.Subcontainers)
+	if err != nil {
+		handleError(response, err)
+		return
+	}
+	writeResponse(response, stats)
+}
+
+// Handles kubernetes pod/container stats requests to:
+// /stats/<pod name>/<container name>
+// /stats/<namespace>/<pod name>/<uid>/<container name>
+func (h *handler) handlePodContainer(request *restful.Request, response *restful.Response) {
+	query, err := parseStatsRequest(request)
+	if err != nil {
+		handleError(response, err)
+		return
+	}
+
+	// Default parameters.
+	params := map[string]string{
+		"namespace": api.NamespaceDefault,
+		"uid":       "",
+	}
+	for k, v := range request.PathParameters() {
+		params[k] = v
+	}
+
+	if params["podName"] == "" || params["containerName"] == "" {
+		response.WriteErrorString(http.StatusBadRequest,
+			fmt.Sprintf("Invalid pod container request: %v", params))
+		return
+	}
+
+	pod, ok := h.provider.GetPodByName(params["namespace"], params["podName"])
+	if !ok {
+		glog.V(4).Infof("Container not found: %v", params)
+		handleError(response, kubecontainer.ErrContainerNotFound)
+		return
+	}
+	stats, err := h.provider.GetContainerInfo(
+		kubecontainer.GetPodFullName(pod),
+		types.UID(params["uid"]),
+		params["containerName"],
+		query.cadvisorRequest())
+
+	if err != nil {
+		handleError(response, err)
+		return
+	}
+	writeResponse(response, stats)
+}
+
+func writeResponse(response *restful.Response, stats interface{}) {
+	if stats == nil {
+		return
+	}
+	err := response.WriteAsJson(stats)
+	if err != nil {
+		handleError(response, err)
+	}
+}
+
+// handleError serializes an error object into an HTTP response.
+func handleError(response *restful.Response, err error) {
+	switch err {
+	case kubecontainer.ErrContainerNotFound:
+		response.WriteError(http.StatusNotFound, err)
+	default:
+		msg := fmt.Sprintf("Internal Error: %v", err)
+		glog.Infof("HTTP InternalServerError: %s", msg)
+		response.WriteErrorString(http.StatusInternalServerError, msg)
+	}
+}

test/e2e/kubelet_stats.go

@@ -34,7 +34,7 @@ import (
 	"k8s.io/kubernetes/pkg/api"
 	client "k8s.io/kubernetes/pkg/client/unversioned"
 	"k8s.io/kubernetes/pkg/kubelet/metrics"
-	"k8s.io/kubernetes/pkg/kubelet/server"
+	"k8s.io/kubernetes/pkg/kubelet/server/stats"
 	"k8s.io/kubernetes/pkg/master/ports"
 	"k8s.io/kubernetes/pkg/util"
 	"k8s.io/kubernetes/pkg/util/sets"
@@ -147,7 +147,7 @@ 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 *server.StatsRequest) (map[string]cadvisorapi.ContainerInfo, error) {
+func getContainerInfo(c *client.Client, nodeName string, req *stats.StatsRequest) (map[string]cadvisorapi.ContainerInfo, error) {
 	reqBody, err := json.Marshal(req)
 	if err != nil {
 		return nil, err
@@ -240,7 +240,7 @@ 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, &server.StatsRequest{
+	containerInfos, err := getContainerInfo(c, nodeName, &stats.StatsRequest{
 		ContainerName: "/",
 		NumStats:      numStats,
 		Subcontainers: true,
@@ -408,7 +408,7 @@ 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, &server.StatsRequest{
+	infos, err := getContainerInfo(r.client, r.node, &stats.StatsRequest{
 		ContainerName: "/",
 		NumStats:      1,
 		Subcontainers: true,