add metrics

Signed-off-by: LiHui <andrewli@yunify.com>

pkg/utils/metrics/endpoint.go

@@ -0,0 +1,35 @@
+package metrics
+
+import (
+	compbasemetrics "k8s.io/component-base/metrics"
+)
+
+var (
+	RequestCounter = compbasemetrics.NewCounterVec(
+		&compbasemetrics.CounterOpts{
+			Name:           "ks_server_request_total",
+			Help:           "Counter of ks_server requests broken out for each verb, group, version, resource and HTTP response code.",
+			StabilityLevel: compbasemetrics.ALPHA,
+		},
+		[]string{"verb", "group", "version", "resource", "code"},
+	)
+
+	RequestLatencies = compbasemetrics.NewHistogramVec(
+		&compbasemetrics.HistogramOpts{
+			Name: "ks_server_request_duration_seconds",
+			Help: "Response latency distribution in seconds for each verb, group, version, resource",
+			// This metric is used for verifying api call latencies SLO,
+			// as well as tracking regressions in this aspects.
+			// Thus we customize buckets significantly, to empower both usecases.
+			Buckets: []float64{0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0,
+				1.25, 1.5, 1.75, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 40, 50, 60},
+			StabilityLevel: compbasemetrics.ALPHA,
+		},
+		[]string{"verb", "group", "version", "resource"},
+	)
+
+	metrics = []compbasemetrics.Registerable{
+		RequestCounter,
+		RequestLatencies,
+	}
+)

pkg/utils/metrics/metrics.go

@@ -0,0 +1,65 @@
+package metrics
+
+import (
+	"github.com/emicklei/go-restful"
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
+	apimachineryversion "k8s.io/apimachinery/pkg/version"
+	compbasemetrics "k8s.io/component-base/metrics"
+	ksVersion "kubesphere.io/kubesphere/pkg/version"
+	"net/http"
+	"sync"
+)
+
+var (
+	Defaults DefaultMetrics
+	//registerMetrics sync.Once
+	defaultRegistry = compbasemetrics.NewKubeRegistry()
+	// MustRegister registers registerable metrics but uses the defaultRegistry, panic upon the first registration that causes an error
+	MustRegister = defaultRegistry.MustRegister
+	// Register registers a collectable metric but uses the defaultRegistry
+	Register = defaultRegistry.Register
+)
+
+// DefaultMetrics installs the default prometheus metrics handler
+type DefaultMetrics struct{}
+
+// Install adds the DefaultMetrics handler
+func (m DefaultMetrics) Install(c *restful.Container) {
+	register()
+	c.Handle("/kapis/metrics", Handler())
+}
+
+func versionGet() apimachineryversion.Info {
+	info := ksVersion.Get()
+	return apimachineryversion.Info{
+		Major:        info.GitMajor,
+		Minor:        info.GitMinor,
+		GitVersion:   info.GitVersion,
+		GitCommit:    info.GitCommit,
+		GitTreeState: info.GitTreeState,
+		BuildDate:    info.BuildDate,
+		GoVersion:    info.GoVersion,
+		Compiler:     info.Compiler,
+		Platform:     info.Platform,
+	}
+}
+
+// Handler returns an HTTP handler for the DefaultGatherer. It is
+// already instrumented with InstrumentHandler (using "prometheus" as handler
+// name).
+func Handler() http.Handler {
+	return promhttp.InstrumentMetricHandler(prometheus.DefaultRegisterer, promhttp.HandlerFor(defaultRegistry, promhttp.HandlerOpts{}))
+}
+
+var registerMetrics sync.Once
+
+func register() {
+	registerMetrics.Do(func() {
+		defaultRegistry.RawMustRegister(prometheus.NewProcessCollector(prometheus.ProcessCollectorOpts{}))
+		defaultRegistry.RawMustRegister(prometheus.NewGoCollector())
+		for _, metric := range metrics {
+			MustRegister(metric)
+		}
+	})
+}