Merge pull request #86282 from RainbowMango/pr_refactor_resource_endpoint

Refactor kubelet resource metrics

pkg/kubelet/apis/resourcemetrics/v1alpha1/config.go

@@ -24,6 +24,11 @@ import (
 	"k8s.io/kubernetes/pkg/kubelet/server/stats"
 )
 
+// This file contains a series of deprecated metrics which we emit them by endpoint `/metrics/resource/v1alpha1`.
+// These metrics have been adapted to new endpoint `/metrics/resource` as well as new `Desc`s.
+// In general, we don't need to maintain these deprecated metrics any more.
+// TODO(RainbowMango): Remove this file in release 1.20.0+.
+
 // Version is the string representation of the version of this configuration
 const Version = "v1alpha1"
 
@@ -33,28 +38,28 @@ var (
 		nil,
 		nil,
 		metrics.ALPHA,
-		"")
+		"1.18.0")
 
 	nodeMemoryUsageDesc = metrics.NewDesc("node_memory_working_set_bytes",
 		"Current working set of the node in bytes",
 		nil,
 		nil,
 		metrics.ALPHA,
-		"")
+		"1.18.0")
 
 	containerCPUUsageDesc = metrics.NewDesc("container_cpu_usage_seconds_total",
 		"Cumulative cpu time consumed by the container in core-seconds",
 		[]string{"container", "pod", "namespace"},
 		nil,
 		metrics.ALPHA,
-		"")
+		"1.18.0")
 
 	containerMemoryUsageDesc = metrics.NewDesc("container_memory_working_set_bytes",
 		"Current working set of the container in bytes",
 		[]string{"container", "pod", "namespace"},
 		nil,
 		metrics.ALPHA,
-		"")
+		"1.18.0")
 )
 
 // getNodeCPUMetrics returns CPU utilization of a node.

pkg/kubelet/metrics/collectors/BUILD

@@ -4,6 +4,7 @@ go_library(
     name = "go_default_library",
     srcs = [
         "log_metrics.go",
+        "resource_metrics.go",
         "volume_stats.go",
     ],
     importpath = "k8s.io/kubernetes/pkg/kubelet/metrics/collectors",
@@ -22,6 +23,7 @@ go_test(
     name = "go_default_test",
     srcs = [
         "log_metrics_test.go",
+        "resource_metrics_test.go",
         "volume_stats_test.go",
     ],
     embed = [":go_default_library"],
@@ -30,6 +32,7 @@ go_test(
         "//pkg/kubelet/server/stats/testing:go_default_library",
         "//staging/src/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
         "//staging/src/k8s.io/component-base/metrics/testutil:go_default_library",
+        "//vendor/github.com/stretchr/testify/mock:go_default_library",
     ],
 )
 

pkg/kubelet/metrics/collectors/resource_metrics.go

@@ -0,0 +1,153 @@
+/*
+Copyright 2019 The Kubernetes Authors.
+
+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 collectors
+
+import (
+	"time"
+
+	"k8s.io/component-base/metrics"
+	"k8s.io/klog"
+	summary "k8s.io/kubernetes/pkg/kubelet/apis/stats/v1alpha1"
+	"k8s.io/kubernetes/pkg/kubelet/server/stats"
+)
+
+var (
+	nodeCPUUsageDesc = metrics.NewDesc("node_cpu_usage_seconds",
+		"Cumulative cpu time consumed by the node in core-seconds",
+		nil,
+		nil,
+		metrics.ALPHA,
+		"")
+
+	nodeMemoryUsageDesc = metrics.NewDesc("node_memory_working_set_bytes",
+		"Current working set of the node in bytes",
+		nil,
+		nil,
+		metrics.ALPHA,
+		"")
+
+	containerCPUUsageDesc = metrics.NewDesc("container_cpu_usage_seconds",
+		"Cumulative cpu time consumed by the container in core-seconds",
+		[]string{"container", "pod", "namespace"},
+		nil,
+		metrics.ALPHA,
+		"")
+
+	containerMemoryUsageDesc = metrics.NewDesc("container_memory_working_set_bytes",
+		"Current working set of the container in bytes",
+		[]string{"container", "pod", "namespace"},
+		nil,
+		metrics.ALPHA,
+		"")
+
+	resouceScrapeResultDesc = metrics.NewDesc("scrape_error",
+		"1 if there was an error while getting container metrics, 0 otherwise",
+		nil,
+		nil,
+		metrics.ALPHA,
+		"")
+)
+
+// NewResourceMetricsCollector returns a metrics.StableCollector which exports resource metrics
+func NewResourceMetricsCollector(provider stats.SummaryProvider) metrics.StableCollector {
+	return &resourceMetricsCollector{
+		provider: provider,
+	}
+}
+
+type resourceMetricsCollector struct {
+	metrics.BaseStableCollector
+
+	provider stats.SummaryProvider
+}
+
+// Check if resourceMetricsCollector implements necessary interface
+var _ metrics.StableCollector = &resourceMetricsCollector{}
+
+// DescribeWithStability implements metrics.StableCollector
+func (rc *resourceMetricsCollector) DescribeWithStability(ch chan<- *metrics.Desc) {
+	ch <- nodeCPUUsageDesc
+	ch <- nodeMemoryUsageDesc
+	ch <- containerCPUUsageDesc
+	ch <- containerMemoryUsageDesc
+	ch <- resouceScrapeResultDesc
+}
+
+// CollectWithStability implements metrics.StableCollector
+// Since new containers are frequently created and removed, using the Gauge would
+// leak metric collectors for containers or pods that no longer exist.  Instead, implement
+// custom collector in a way that only collects metrics for active containers.
+func (rc *resourceMetricsCollector) CollectWithStability(ch chan<- metrics.Metric) {
+	var errorCount float64
+	defer func() {
+		ch <- metrics.NewLazyConstMetric(resouceScrapeResultDesc, metrics.GaugeValue, errorCount)
+	}()
+	statsSummary, err := rc.provider.GetCPUAndMemoryStats()
+	if err != nil {
+		errorCount = 1
+		klog.Warningf("Error getting summary for resourceMetric prometheus endpoint: %v", err)
+		return
+	}
+
+	rc.collectNodeCPUMetrics(ch, statsSummary.Node)
+	rc.collectNodeMemoryMetrics(ch, statsSummary.Node)
+
+	for _, pod := range statsSummary.Pods {
+		for _, container := range pod.Containers {
+			rc.collectContainerCPUMetrics(ch, pod, container)
+			rc.collectContainerMemoryMetrics(ch, pod, container)
+		}
+	}
+}
+
+func (rc *resourceMetricsCollector) collectNodeCPUMetrics(ch chan<- metrics.Metric, s summary.NodeStats) {
+	if s.CPU == nil {
+		return
+	}
+
+	ch <- metrics.NewLazyMetricWithTimestamp(s.CPU.Time.Time,
+		metrics.NewLazyConstMetric(nodeCPUUsageDesc, metrics.GaugeValue, float64(*s.CPU.UsageCoreNanoSeconds)/float64(time.Second)))
+}
+
+func (rc *resourceMetricsCollector) collectNodeMemoryMetrics(ch chan<- metrics.Metric, s summary.NodeStats) {
+	if s.Memory == nil {
+		return
+	}
+
+	ch <- metrics.NewLazyMetricWithTimestamp(s.Memory.Time.Time,
+		metrics.NewLazyConstMetric(nodeMemoryUsageDesc, metrics.GaugeValue, float64(*s.Memory.WorkingSetBytes)))
+}
+
+func (rc *resourceMetricsCollector) collectContainerCPUMetrics(ch chan<- metrics.Metric, pod summary.PodStats, s summary.ContainerStats) {
+	if s.CPU == nil {
+		return
+	}
+
+	ch <- metrics.NewLazyMetricWithTimestamp(s.CPU.Time.Time,
+		metrics.NewLazyConstMetric(containerCPUUsageDesc, metrics.GaugeValue,
+			float64(*s.CPU.UsageCoreNanoSeconds)/float64(time.Second), s.Name, pod.PodRef.Name, pod.PodRef.Namespace))
+}
+
+func (rc *resourceMetricsCollector) collectContainerMemoryMetrics(ch chan<- metrics.Metric, pod summary.PodStats, s summary.ContainerStats) {
+	if s.Memory == nil {
+		return
+	}
+
+	ch <- metrics.NewLazyMetricWithTimestamp(s.Memory.Time.Time,
+		metrics.NewLazyConstMetric(containerMemoryUsageDesc, metrics.GaugeValue,
+			float64(*s.Memory.WorkingSetBytes), s.Name, pod.PodRef.Name, pod.PodRef.Namespace))
+}

pkg/kubelet/metrics/collectors/resource_metrics_test.go

@@ -0,0 +1,189 @@
+/*
+Copyright 2019 The Kubernetes Authors.
+
+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 collectors
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/mock"
+
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/component-base/metrics/testutil"
+	statsapi "k8s.io/kubernetes/pkg/kubelet/apis/stats/v1alpha1"
+)
+
+type mockSummaryProvider struct {
+	mock.Mock
+}
+
+func (m *mockSummaryProvider) Get(updateStats bool) (*statsapi.Summary, error) {
+	args := m.Called(updateStats)
+	return args.Get(0).(*statsapi.Summary), args.Error(1)
+}
+
+func (m *mockSummaryProvider) GetCPUAndMemoryStats() (*statsapi.Summary, error) {
+	args := m.Called()
+	return args.Get(0).(*statsapi.Summary), args.Error(1)
+}
+
+func TestCollectResourceMetrics(t *testing.T) {
+	testTime := metav1.NewTime(time.Unix(2, 0)) // a static timestamp: 2000
+	interestedMetrics := []string{
+		"scrape_error",
+		"node_cpu_usage_seconds",
+		"node_memory_working_set_bytes",
+		"container_cpu_usage_seconds",
+		"container_memory_working_set_bytes",
+	}
+
+	tests := []struct {
+		name            string
+		summary         *statsapi.Summary
+		summaryErr      error
+		expectedMetrics string
+	}{
+		{
+			name:       "error getting summary",
+			summary:    nil,
+			summaryErr: fmt.Errorf("failed to get summary"),
+			expectedMetrics: `
+				# HELP scrape_error [ALPHA] 1 if there was an error while getting container metrics, 0 otherwise
+				# TYPE scrape_error gauge
+				scrape_error 1
+			`,
+		},
+		{
+			name: "arbitrary node metrics",
+			summary: &statsapi.Summary{
+				Node: statsapi.NodeStats{
+					CPU: &statsapi.CPUStats{
+						Time:                 testTime,
+						UsageCoreNanoSeconds: uint64Ptr(10000000000),
+					},
+					Memory: &statsapi.MemoryStats{
+						Time:            testTime,
+						WorkingSetBytes: uint64Ptr(1000),
+					},
+				},
+			},
+			summaryErr: nil,
+			expectedMetrics: `
+				# HELP node_cpu_usage_seconds [ALPHA] Cumulative cpu time consumed by the node in core-seconds
+				# TYPE node_cpu_usage_seconds gauge
+				node_cpu_usage_seconds 10 2000
+				# HELP node_memory_working_set_bytes [ALPHA] Current working set of the node in bytes
+				# TYPE node_memory_working_set_bytes gauge
+				node_memory_working_set_bytes 1000 2000
+				# HELP scrape_error [ALPHA] 1 if there was an error while getting container metrics, 0 otherwise
+				# TYPE scrape_error gauge
+				scrape_error 0
+			`,
+		},
+		{
+			name: "arbitrary container metrics for different container, pods and namespaces",
+			summary: &statsapi.Summary{
+				Pods: []statsapi.PodStats{
+					{
+						PodRef: statsapi.PodReference{
+							Name:      "pod_a",
+							Namespace: "namespace_a",
+						},
+						Containers: []statsapi.ContainerStats{
+							{
+								Name: "container_a",
+								CPU: &statsapi.CPUStats{
+									Time:                 testTime,
+									UsageCoreNanoSeconds: uint64Ptr(10000000000),
+								},
+								Memory: &statsapi.MemoryStats{
+									Time:            testTime,
+									WorkingSetBytes: uint64Ptr(1000),
+								},
+							},
+							{
+								Name: "container_b",
+								CPU: &statsapi.CPUStats{
+									Time:                 testTime,
+									UsageCoreNanoSeconds: uint64Ptr(10000000000),
+								},
+								Memory: &statsapi.MemoryStats{
+									Time:            testTime,
+									WorkingSetBytes: uint64Ptr(1000),
+								},
+							},
+						},
+					},
+					{
+						PodRef: statsapi.PodReference{
+							Name:      "pod_b",
+							Namespace: "namespace_b",
+						},
+						Containers: []statsapi.ContainerStats{
+							{
+								Name: "container_a",
+								CPU: &statsapi.CPUStats{
+									Time:                 testTime,
+									UsageCoreNanoSeconds: uint64Ptr(10000000000),
+								},
+								Memory: &statsapi.MemoryStats{
+									Time:            testTime,
+									WorkingSetBytes: uint64Ptr(1000),
+								},
+							},
+						},
+					},
+				},
+			},
+			summaryErr: nil,
+			expectedMetrics: `
+				# HELP scrape_error [ALPHA] 1 if there was an error while getting container metrics, 0 otherwise
+				# TYPE scrape_error gauge
+				scrape_error 0
+				# HELP container_cpu_usage_seconds [ALPHA] Cumulative cpu time consumed by the container in core-seconds
+				# TYPE container_cpu_usage_seconds gauge
+				container_cpu_usage_seconds{container="container_a",namespace="namespace_a",pod="pod_a"} 10 2000
+				container_cpu_usage_seconds{container="container_a",namespace="namespace_b",pod="pod_b"} 10 2000
+				container_cpu_usage_seconds{container="container_b",namespace="namespace_a",pod="pod_a"} 10 2000
+				# HELP container_memory_working_set_bytes [ALPHA] Current working set of the container in bytes
+				# TYPE container_memory_working_set_bytes gauge
+				container_memory_working_set_bytes{container="container_a",namespace="namespace_a",pod="pod_a"} 1000 2000
+				container_memory_working_set_bytes{container="container_a",namespace="namespace_b",pod="pod_b"} 1000 2000
+				container_memory_working_set_bytes{container="container_b",namespace="namespace_a",pod="pod_a"} 1000 2000
+			`,
+		},
+	}
+
+	for _, test := range tests {
+		tc := test
+		t.Run(tc.name, func(t *testing.T) {
+			provider := &mockSummaryProvider{}
+			provider.On("GetCPUAndMemoryStats").Return(tc.summary, tc.summaryErr)
+			collector := NewResourceMetricsCollector(provider)
+
+			if err := testutil.CustomCollectAndCompare(collector, strings.NewReader(tc.expectedMetrics), interestedMetrics...); err != nil {
+				t.Fatal(err)
+			}
+		})
+	}
+}
+
+func uint64Ptr(u uint64) *uint64 {
+	return &u
+}

pkg/kubelet/server/BUILD

@@ -22,6 +22,7 @@ go_library(
         "//pkg/kubelet/apis/podresources/v1alpha1:go_default_library",
         "//pkg/kubelet/apis/resourcemetrics/v1alpha1:go_default_library",
         "//pkg/kubelet/container:go_default_library",
+        "//pkg/kubelet/metrics/collectors:go_default_library",
         "//pkg/kubelet/prober:go_default_library",
         "//pkg/kubelet/server/metrics:go_default_library",
         "//pkg/kubelet/server/portforward:go_default_library",

pkg/kubelet/server/auth_test.go

@@ -128,6 +128,7 @@ func AuthzTestCases() []AuthzTestCase {
 		"/metrics/cadvisor":                   "metrics",
 		"/metrics/probes":                     "metrics",
 		"/metrics/resource/v1alpha1":          "metrics",
+		"/metrics/resource":                   "metrics",
 		"/pods/":                              "proxy",
 		"/portForward/{podNamespace}/{podID}": "proxy",
 		"/portForward/{podNamespace}/{podID}/{uid}":         "proxy",

pkg/kubelet/server/server.go

@@ -38,6 +38,7 @@ import (
 	"github.com/google/cadvisor/metrics"
 	"google.golang.org/grpc"
 	"k8s.io/klog"
+	"k8s.io/kubernetes/pkg/kubelet/metrics/collectors"
 
 	"k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
@@ -76,7 +77,7 @@ import (
 const (
 	metricsPath         = "/metrics"
 	cadvisorMetricsPath = "/metrics/cadvisor"
-	resourceMetricsPathPrefix = "/metrics/resource"
+	resourceMetricsPath = "/metrics/resource"
 	proberMetricsPath   = "/metrics/probes"
 	specPath            = "/spec/"
 	statsPath           = "/stats/"
@@ -319,12 +320,19 @@ func (s *Server) InstallDefaultHandlers(enableCAdvisorJSONEndpoints bool) {
 		compbasemetrics.HandlerFor(r, compbasemetrics.HandlerOpts{ErrorHandling: compbasemetrics.ContinueOnError}),
 	)
 
+	// deprecated endpoint which will be removed in release 1.20.0+.
 	v1alpha1ResourceRegistry := compbasemetrics.NewKubeRegistry()
 	v1alpha1ResourceRegistry.CustomMustRegister(stats.NewPrometheusResourceMetricCollector(s.resourceAnalyzer, v1alpha1.Config()))
-	s.restfulCont.Handle(path.Join(resourceMetricsPathPrefix, v1alpha1.Version),
+	s.restfulCont.Handle(path.Join(resourceMetricsPath, v1alpha1.Version),
 		compbasemetrics.HandlerFor(v1alpha1ResourceRegistry, compbasemetrics.HandlerOpts{ErrorHandling: compbasemetrics.ContinueOnError}),
 	)
 
+	resourceRegistry := compbasemetrics.NewKubeRegistry()
+	resourceRegistry.CustomMustRegister(collectors.NewResourceMetricsCollector(s.resourceAnalyzer))
+	s.restfulCont.Handle(resourceMetricsPath,
+		compbasemetrics.HandlerFor(resourceRegistry, compbasemetrics.HandlerOpts{ErrorHandling: compbasemetrics.ContinueOnError}),
+	)
+
 	// prober metrics are exposed under a different endpoint
 
 	p := compbasemetrics.NewKubeRegistry()

pkg/kubelet/server/stats/prometheus_resource_metrics.go

@@ -60,7 +60,7 @@ func NewPrometheusResourceMetricCollector(provider SummaryProvider, config Resou
 			nil,
 			nil,
 			metrics.ALPHA,
-			""),
+			"1.18.0"),
 	}
 }