Merge pull request #491 from monnand/cadvisor-update-3

Retrieve machine spec from cAdvisor

pkg/client/containerinfo.go

@@ -29,8 +29,12 @@ import (
 )
 
 type ContainerInfoGetter interface {
+	// GetContainerInfo returns information about a container.
 	GetContainerInfo(host, podID, containerID string, req *info.ContainerInfoRequest) (*info.ContainerInfo, error)
-	GetMachineInfo(host string, req *info.ContainerInfoRequest) (*info.ContainerInfo, error)
+	// GetRootInfo returns information about the root container on a machine.
+	GetRootInfo(host string, req *info.ContainerInfoRequest) (*info.ContainerInfo, error)
+	// GetMachineInfo returns the machine's information like number of cores, memory capacity.
+	GetMachineInfo(host string) (*info.MachineInfo, error)
 }
 
 type HTTPContainerInfoGetter struct {
@@ -38,6 +42,35 @@ type HTTPContainerInfoGetter struct {
 	Port   int
 }
 
+func (self *HTTPContainerInfoGetter) GetMachineInfo(host string) (*info.MachineInfo, error) {
+	request, err := http.NewRequest(
+		"GET",
+		fmt.Sprintf("http://%v/spec",
+			net.JoinHostPort(host, strconv.Itoa(self.Port)),
+		),
+		nil,
+	)
+	if err != nil {
+		return nil, err
+	}
+
+	response, err := self.Client.Do(request)
+	if err != nil {
+		return nil, err
+	}
+	defer response.Body.Close()
+	if response.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("trying to get machine spec from %v; received status %v",
+			host, response.Status)
+	}
+	var minfo info.MachineInfo
+	err = json.NewDecoder(response.Body).Decode(&minfo)
+	if err != nil {
+		return nil, err
+	}
+	return &minfo, nil
+}
+
 func (self *HTTPContainerInfoGetter) getContainerInfo(host, path string, req *info.ContainerInfoRequest) (*info.ContainerInfo, error) {
 	var body io.Reader
 	if req != nil {
@@ -69,9 +102,8 @@ func (self *HTTPContainerInfoGetter) getContainerInfo(host, path string, req *in
 		return nil, fmt.Errorf("trying to get info for %v from %v; received status %v",
 			path, host, response.Status)
 	}
-	decoder := json.NewDecoder(response.Body)
 	var cinfo info.ContainerInfo
-	err = decoder.Decode(&cinfo)
+	err = json.NewDecoder(response.Body).Decode(&cinfo)
 	if err != nil {
 		return nil, err
 	}
@@ -86,6 +118,6 @@ func (self *HTTPContainerInfoGetter) GetContainerInfo(host, podID, containerID s
 	)
 }
 
-func (self *HTTPContainerInfoGetter) GetMachineInfo(host string, req *info.ContainerInfoRequest) (*info.ContainerInfo, error) {
+func (self *HTTPContainerInfoGetter) GetRootInfo(host string, req *info.ContainerInfoRequest) (*info.ContainerInfo, error) {
 	return self.getContainerInfo(host, "", req)
 }

pkg/client/containerinfo_test.go

@@ -53,9 +53,8 @@ func testHTTPContainerInfoGetter(
 				expectedPath, r.URL.Path)
 		}
 
-		decoder := json.NewDecoder(r.Body)
 		var receivedReq info.ContainerInfoRequest
-		err := decoder.Decode(&receivedReq)
+		err := json.NewDecoder(r.Body).Decode(&receivedReq)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -67,8 +66,7 @@ func testHTTPContainerInfoGetter(
 		if !reflect.DeepEqual(expectedReq, &receivedReq) {
 			t.Errorf("received wrong request")
 		}
-		encoder := json.NewEncoder(w)
+		err = json.NewEncoder(w).Encode(cinfo)
-		err = encoder.Encode(cinfo)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -93,7 +91,7 @@ func testHTTPContainerInfoGetter(
 	if len(podID) > 0 && len(containerID) > 0 {
 		receivedContainerInfo, err = containerInfoGetter.GetContainerInfo(parts[0], podID, containerID, req)
 	} else {
-		receivedContainerInfo, err = containerInfoGetter.GetMachineInfo(parts[0], req)
+		receivedContainerInfo, err = containerInfoGetter.GetRootInfo(parts[0], req)
 	}
 	if status == 0 || status == http.StatusOK {
 		if err != nil {
@@ -125,7 +123,7 @@ func TestHTTPContainerInfoGetterGetContainerInfoSuccessfully(t *testing.T) {
 	testHTTPContainerInfoGetter(req, cinfo, "somePodID", "containerNameInK8S", 0, t)
 }
 
-func TestHTTPContainerInfoGetterGetMachineInfoSuccessfully(t *testing.T) {
+func TestHTTPContainerInfoGetterGetRootInfoSuccessfully(t *testing.T) {
 	req := &info.ContainerInfoRequest{
 		NumStats:   10,
 		NumSamples: 10,
@@ -155,7 +153,7 @@ func TestHTTPContainerInfoGetterGetContainerInfoWithError(t *testing.T) {
 	testHTTPContainerInfoGetter(req, cinfo, "somePodID", "containerNameInK8S", http.StatusNotFound, t)
 }
 
-func TestHTTPContainerInfoGetterGetMachineInfoWithError(t *testing.T) {
+func TestHTTPContainerInfoGetterGetRootInfoWithError(t *testing.T) {
 	req := &info.ContainerInfoRequest{
 		NumStats:   10,
 		NumSamples: 10,
@@ -169,3 +167,39 @@ func TestHTTPContainerInfoGetterGetMachineInfoWithError(t *testing.T) {
 	)
 	testHTTPContainerInfoGetter(req, cinfo, "", "", http.StatusNotFound, t)
 }
+
+func TestHTTPGetMachineInfo(t *testing.T) {
+	mspec := &info.MachineInfo{
+		NumCores:       4,
+		MemoryCapacity: 2048,
+	}
+	ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		err := json.NewEncoder(w).Encode(mspec)
+		if err != nil {
+			t.Fatal(err)
+		}
+	}))
+	hostURL, err := url.Parse(ts.URL)
+	if err != nil {
+		t.Fatal(err)
+	}
+	parts := strings.Split(hostURL.Host, ":")
+
+	port, err := strconv.Atoi(parts[1])
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	containerInfoGetter := &HTTPContainerInfoGetter{
+		Client: http.DefaultClient,
+		Port:   port,
+	}
+
+	received, err := containerInfoGetter.GetMachineInfo(parts[0])
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !reflect.DeepEqual(received, mspec) {
+		t.Errorf("received wrong machine spec")
+	}
+}

pkg/kubelet/kubelet.go

@@ -769,11 +769,15 @@ func (kl *Kubelet) GetContainerInfo(manifestID, containerName string, req *info.
 	return kl.statsFromContainerPath(fmt.Sprintf("/docker/%s", dockerContainer.ID), req)
 }
 
-// GetMachineStats returns stats (from Cadvisor) of current machine.
+// GetRootInfo returns stats (from Cadvisor) of current machine (root container).
-func (kl *Kubelet) GetMachineStats(req *info.ContainerInfoRequest) (*info.ContainerInfo, error) {
+func (kl *Kubelet) GetRootInfo(req *info.ContainerInfoRequest) (*info.ContainerInfo, error) {
 	return kl.statsFromContainerPath("/", req)
 }
 
+func (kl *Kubelet) GetMachineInfo() (*info.MachineInfo, error) {
+	return kl.CadvisorClient.MachineInfo()
+}
+
 func (kl *Kubelet) healthy(container api.Container, dockerContainer *docker.APIContainers) (health.Status, error) {
 	// Give the container 60 seconds to start up.
 	if container.LivenessProbe == nil {

pkg/kubelet/kubelet_test.go

@@ -948,7 +948,7 @@ func areSamePercentiles(
 	}
 }
 
-func TestGetContainerStats(t *testing.T) {
+func TestGetContainerInfo(t *testing.T) {
 	containerID := "ab2cdf"
 	containerPath := fmt.Sprintf("/docker/%v", containerID)
 	containerInfo := &info.ContainerInfo{
@@ -1001,7 +1001,7 @@ func TestGetContainerStats(t *testing.T) {
 	mockCadvisor.AssertExpectations(t)
 }
 
-func TestGetMachineStats(t *testing.T) {
+func TestGetRooInfo(t *testing.T) {
 	containerPath := "/"
 	containerInfo := &info.ContainerInfo{
 		ContainerReference: info.ContainerReference{
@@ -1032,7 +1032,7 @@ func TestGetMachineStats(t *testing.T) {
 	}
 
 	// If the container name is an empty string, then it means the root container.
-	stats, err := kubelet.GetMachineStats(req)
+	stats, err := kubelet.GetRootInfo(req)
 	if err != nil {
 		t.Errorf("unexpected error: %v", err)
 	}
@@ -1044,7 +1044,7 @@ func TestGetMachineStats(t *testing.T) {
 	mockCadvisor.AssertExpectations(t)
 }
 
-func TestGetContainerStatsWithoutCadvisor(t *testing.T) {
+func TestGetContainerInfoWithoutCadvisor(t *testing.T) {
 	kubelet, _, fakeDocker := makeTestKubelet(t)
 	fakeDocker.containerList = []docker.APIContainers{
 		{
@@ -1071,7 +1071,7 @@ func TestGetContainerStatsWithoutCadvisor(t *testing.T) {
 	}
 }
 
-func TestGetContainerStatsWhenCadvisorFailed(t *testing.T) {
+func TestGetContainerInfoWhenCadvisorFailed(t *testing.T) {
 	containerID := "ab2cdf"
 	containerPath := fmt.Sprintf("/docker/%v", containerID)
 
@@ -1107,7 +1107,7 @@ func TestGetContainerStatsWhenCadvisorFailed(t *testing.T) {
 	mockCadvisor.AssertExpectations(t)
 }
 
-func TestGetContainerStatsOnNonExistContainer(t *testing.T) {
+func TestGetContainerInfoOnNonExistContainer(t *testing.T) {
 	mockCadvisor := &mockCadvisorClient{}
 
 	kubelet, _, fakeDocker := makeTestKubelet(t)

pkg/kubelet/server.go

@@ -44,7 +44,8 @@ type Server struct {
 // For testablitiy.
 type kubeletInterface interface {
 	GetContainerInfo(podID, containerName string, req *info.ContainerInfoRequest) (*info.ContainerInfo, error)
-	GetMachineStats(req *info.ContainerInfoRequest) (*info.ContainerInfo, error)
+	GetRootInfo(req *info.ContainerInfoRequest) (*info.ContainerInfo, error)
+	GetMachineInfo() (*info.MachineInfo, error)
 	GetPodInfo(name string) (api.PodInfo, error)
 }
 
@@ -108,6 +109,19 @@ func (s *Server) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 		w.Write(data)
 	case strings.HasPrefix(u.Path, "/stats"):
 		s.serveStats(w, req)
+	case strings.HasPrefix(u.Path, "/spec"):
+		info, err := s.Kubelet.GetMachineInfo()
+		if err != nil {
+			s.error(w, err)
+			return
+		}
+		data, err := json.Marshal(info)
+		if err != nil {
+			s.error(w, err)
+			return
+		}
+		w.Header().Add("Content-type", "application/json")
+		w.Write(data)
 	default:
 		s.DelegateHandler.ServeHTTP(w, req)
 	}
@@ -119,8 +133,7 @@ func (s *Server) serveStats(w http.ResponseWriter, req *http.Request) {
 	var stats *info.ContainerInfo
 	var err error
 	var query info.ContainerInfoRequest
-	decoder := json.NewDecoder(req.Body)
+	err = json.NewDecoder(req.Body).Decode(&query)
-	err = decoder.Decode(&query)
 	if err != nil && err != io.EOF {
 		s.error(w, err)
 		return
@@ -128,7 +141,7 @@ func (s *Server) serveStats(w http.ResponseWriter, req *http.Request) {
 	switch len(components) {
 	case 1:
 		// Machine stats
-		stats, err = s.Kubelet.GetMachineStats(&query)
+		stats, err = s.Kubelet.GetRootInfo(&query)
 	case 2:
 		// pod stats
 		// TODO(monnand) Implement this

pkg/kubelet/server_test.go

@@ -33,9 +33,10 @@ import (
 )
 
 type fakeKubelet struct {
-	infoFunc           func(name string) (api.PodInfo, error)
+	infoFunc          func(name string) (api.PodInfo, error)
-	containerStatsFunc func(podID, containerName string, req *info.ContainerInfoRequest) (*info.ContainerInfo, error)
+	containerInfoFunc func(podID, containerName string, req *info.ContainerInfoRequest) (*info.ContainerInfo, error)
-	machineStatsFunc   func(query *info.ContainerInfoRequest) (*info.ContainerInfo, error)
+	rootInfoFunc      func(query *info.ContainerInfoRequest) (*info.ContainerInfo, error)
+	machineInfoFunc   func() (*info.MachineInfo, error)
 }
 
 func (fk *fakeKubelet) GetPodInfo(name string) (api.PodInfo, error) {
@@ -43,11 +44,15 @@ func (fk *fakeKubelet) GetPodInfo(name string) (api.PodInfo, error) {
 }
 
 func (fk *fakeKubelet) GetContainerInfo(podID, containerName string, req *info.ContainerInfoRequest) (*info.ContainerInfo, error) {
-	return fk.containerStatsFunc(podID, containerName, req)
+	return fk.containerInfoFunc(podID, containerName, req)
 }
 
-func (fk *fakeKubelet) GetMachineStats(req *info.ContainerInfoRequest) (*info.ContainerInfo, error) {
+func (fk *fakeKubelet) GetRootInfo(req *info.ContainerInfoRequest) (*info.ContainerInfo, error) {
-	return fk.machineStatsFunc(req)
+	return fk.rootInfoFunc(req)
+}
+
+func (fk *fakeKubelet) GetMachineInfo() (*info.MachineInfo, error) {
+	return fk.machineInfoFunc()
 }
 
 type serverTestFramework struct {
@@ -147,9 +152,9 @@ func TestPodInfo(t *testing.T) {
 	}
 }
 
-func TestContainerStats(t *testing.T) {
+func TestContainerInfo(t *testing.T) {
 	fw := makeServerTest()
-	expectedStats := &info.ContainerInfo{
+	expectedInfo := &info.ContainerInfo{
 		StatsPercentiles: &info.ContainerStatsPercentiles{
 			MaxMemoryUsage: 1024001,
 			CpuUsagePercentiles: []info.Percentile{
@@ -166,11 +171,11 @@ func TestContainerStats(t *testing.T) {
 	}
 	expectedPodID := "somepod"
 	expectedContainerName := "goodcontainer"
-	fw.fakeKubelet.containerStatsFunc = func(podID, containerName string, req *info.ContainerInfoRequest) (*info.ContainerInfo, error) {
+	fw.fakeKubelet.containerInfoFunc = func(podID, containerName string, req *info.ContainerInfoRequest) (*info.ContainerInfo, error) {
 		if podID != expectedPodID || containerName != expectedContainerName {
 			return nil, fmt.Errorf("bad podID or containerName: podID=%v; containerName=%v", podID, containerName)
 		}
-		return expectedStats, nil
+		return expectedInfo, nil
 	}
 
 	resp, err := http.Get(fw.testHTTPServer.URL + fmt.Sprintf("/stats/%v/%v", expectedPodID, expectedContainerName))
@@ -178,20 +183,19 @@ func TestContainerStats(t *testing.T) {
 		t.Fatalf("Got error GETing: %v", err)
 	}
 	defer resp.Body.Close()
-	var receivedStats info.ContainerInfo
+	var receivedInfo info.ContainerInfo
-	decoder := json.NewDecoder(resp.Body)
+	err = json.NewDecoder(resp.Body).Decode(&receivedInfo)
-	err = decoder.Decode(&receivedStats)
 	if err != nil {
 		t.Fatalf("received invalid json data: %v", err)
 	}
-	if !reflect.DeepEqual(&receivedStats, expectedStats) {
+	if !reflect.DeepEqual(&receivedInfo, expectedInfo) {
-		t.Errorf("received wrong data: %#v", receivedStats)
+		t.Errorf("received wrong data: %#v", receivedInfo)
 	}
 }
 
-func TestMachineStats(t *testing.T) {
+func TestRootInfo(t *testing.T) {
 	fw := makeServerTest()
-	expectedStats := &info.ContainerInfo{
+	expectedInfo := &info.ContainerInfo{
 		StatsPercentiles: &info.ContainerStatsPercentiles{
 			MaxMemoryUsage: 1024001,
 			CpuUsagePercentiles: []info.Percentile{
@@ -206,8 +210,8 @@ func TestMachineStats(t *testing.T) {
 			},
 		},
 	}
-	fw.fakeKubelet.machineStatsFunc = func(req *info.ContainerInfoRequest) (*info.ContainerInfo, error) {
+	fw.fakeKubelet.rootInfoFunc = func(req *info.ContainerInfoRequest) (*info.ContainerInfo, error) {
-		return expectedStats, nil
+		return expectedInfo, nil
 	}
 
 	resp, err := http.Get(fw.testHTTPServer.URL + "/stats")
@@ -215,13 +219,37 @@ func TestMachineStats(t *testing.T) {
 		t.Fatalf("Got error GETing: %v", err)
 	}
 	defer resp.Body.Close()
-	var receivedStats info.ContainerInfo
+	var receivedInfo info.ContainerInfo
-	decoder := json.NewDecoder(resp.Body)
+	err = json.NewDecoder(resp.Body).Decode(&receivedInfo)
-	err = decoder.Decode(&receivedStats)
 	if err != nil {
 		t.Fatalf("received invalid json data: %v", err)
 	}
-	if !reflect.DeepEqual(&receivedStats, expectedStats) {
+	if !reflect.DeepEqual(&receivedInfo, expectedInfo) {
-		t.Errorf("received wrong data: %#v", receivedStats)
+		t.Errorf("received wrong data: %#v", receivedInfo)
+	}
+}
+
+func TestMachineInfo(t *testing.T) {
+	fw := makeServerTest()
+	expectedInfo := &info.MachineInfo{
+		NumCores:       4,
+		MemoryCapacity: 1024,
+	}
+	fw.fakeKubelet.machineInfoFunc = func() (*info.MachineInfo, error) {
+		return expectedInfo, nil
+	}
+
+	resp, err := http.Get(fw.testHTTPServer.URL + "/spec")
+	if err != nil {
+		t.Fatalf("Got error GETing: %v", err)
+	}
+	defer resp.Body.Close()
+	var receivedInfo info.MachineInfo
+	err = json.NewDecoder(resp.Body).Decode(&receivedInfo)
+	if err != nil {
+		t.Fatalf("received invalid json data: %v", err)
+	}
+	if !reflect.DeepEqual(&receivedInfo, expectedInfo) {
+		t.Errorf("received wrong data: %#v", receivedInfo)
 	}
 }