mirror of https://github.com/tailscale/tailscale/
tsweb: move varz handler(s) into separate modules
This splits Prometheus metric handlers exposed by tsweb into two modules: - `varz.Handler` exposes Prometheus metrics generated by our expvar converter; - `promvarz.Handler` combines our expvar-converted metrics and native Prometheus metrics. By default, tsweb will use the promvarz handler, however users can keep using only the expvar converter. Specifically, `tailscaled` now uses `varz.Handler` explicitly, which avoids a dependency on the (heavyweight) Prometheus client. Updates https://github.com/tailscale/corp/issues/10205 Signed-off-by: Anton Tolchanov <anton@tailscale.com>pull/7846/head
Anton Tolchanov
2 years ago
committed by
Anton Tolchanov
parent
c153e6ae2f
commit
8546ff98fb
@ -0,0 +1,48 @@
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// Copyright (c) Tailscale Inc & AUTHORS
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// SPDX-License-Identifier: BSD-3-Clause
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// Package promvarz combines Prometheus metrics exported by our expvar converter
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// (tsweb/varz) with metrics exported by the official Prometheus client.
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package promvarz
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import (
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"fmt"
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"net/http"
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"github.com/prometheus/client_golang/prometheus"
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"github.com/prometheus/common/expfmt"
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"tailscale.com/tsweb/varz"
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)
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// Handler returns Prometheus metrics exported by our expvar converter
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// and the official Prometheus client.
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func Handler(w http.ResponseWriter, r *http.Request) {
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if err := gatherNativePrometheusMetrics(w); err != nil {
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w.WriteHeader(http.StatusInternalServerError)
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w.Write([]byte(err.Error()))
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return
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}
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varz.Handler(w, r)
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}
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// gatherNativePrometheusMetrics writes metrics from the default
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// metric registry in text format.
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func gatherNativePrometheusMetrics(w http.ResponseWriter) error {
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enc := expfmt.NewEncoder(w, expfmt.FmtText)
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mfs, err := prometheus.DefaultGatherer.Gather()
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if err != nil {
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return fmt.Errorf("could not gather metrics from DefaultGatherer: %w", err)
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}
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for _, mf := range mfs {
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if err := enc.Encode(mf); err != nil {
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return fmt.Errorf("could not encode metric %v: %w", mf, err)
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}
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}
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if closer, ok := enc.(expfmt.Closer); ok {
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if err := closer.Close(); err != nil {
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return err
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}
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}
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return nil
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}
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@ -0,0 +1,35 @@
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// Copyright (c) Tailscale Inc & AUTHORS
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// SPDX-License-Identifier: BSD-3-Clause
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package promvarz
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import (
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"expvar"
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"net/http"
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"net/http/httptest"
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"strings"
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"testing"
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"github.com/prometheus/client_golang/prometheus"
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"github.com/prometheus/client_golang/prometheus/promauto"
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"github.com/prometheus/client_golang/prometheus/testutil"
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)
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func TestHandler(t *testing.T) {
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test1 := expvar.NewInt("gauge_promvarz_test_expvar")
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test1.Set(42)
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test2 := promauto.NewGauge(prometheus.GaugeOpts{Name: "promvarz_test_native"})
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test2.Set(4242)
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svr := httptest.NewServer(http.HandlerFunc(Handler))
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defer svr.Close()
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want := `
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# TYPE promvarz_test_expvar gauge
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promvarz_test_expvar 42
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# TYPE promvarz_test_native gauge
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promvarz_test_native 4242
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`
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if err := testutil.ScrapeAndCompare(svr.URL, strings.NewReader(want), "promvarz_test_expvar", "promvarz_test_native"); err != nil {
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t.Error(err)
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}
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}
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@ -0,0 +1,372 @@
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// Copyright (c) Tailscale Inc & AUTHORS
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// SPDX-License-Identifier: BSD-3-Clause
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// Package varz contains code to export metrics in Prometheus format.
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package varz
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import (
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"expvar"
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"fmt"
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"io"
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"net/http"
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_ "net/http/pprof"
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"reflect"
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"runtime"
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"sort"
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"strings"
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"sync"
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"time"
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"tailscale.com/metrics"
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"tailscale.com/version"
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)
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func init() {
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expvar.Publish("process_start_unix_time", expvar.Func(func() any { return timeStart.Unix() }))
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expvar.Publish("version", expvar.Func(func() any { return version.Long() }))
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expvar.Publish("go_version", expvar.Func(func() any { return runtime.Version() }))
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expvar.Publish("counter_uptime_sec", expvar.Func(func() any { return int64(Uptime().Seconds()) }))
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expvar.Publish("gauge_goroutines", expvar.Func(func() any { return runtime.NumGoroutine() }))
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}
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const (
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gaugePrefix = "gauge_"
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counterPrefix = "counter_"
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labelMapPrefix = "labelmap_"
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)
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// prefixesToTrim contains key prefixes to remove when exporting and sorting metrics.
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var prefixesToTrim = []string{gaugePrefix, counterPrefix, labelMapPrefix}
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var timeStart = time.Now()
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func Uptime() time.Duration { return time.Since(timeStart).Round(time.Second) }
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// WritePrometheusExpvar writes kv to w in Prometheus metrics format.
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//
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// See VarzHandler for conventions. This is exported primarily for
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// people to test their varz.
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func WritePrometheusExpvar(w io.Writer, kv expvar.KeyValue) {
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writePromExpVar(w, "", kv)
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}
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type prometheusMetricDetails struct {
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Name string
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Type string
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Label string
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}
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var prometheusMetricCache sync.Map // string => *prometheusMetricDetails
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func prometheusMetric(prefix string, key string) (string, string, string) {
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cachekey := prefix + key
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if v, ok := prometheusMetricCache.Load(cachekey); ok {
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d := v.(*prometheusMetricDetails)
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return d.Name, d.Type, d.Label
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}
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var typ string
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var label string
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switch {
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case strings.HasPrefix(key, gaugePrefix):
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typ = "gauge"
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key = strings.TrimPrefix(key, gaugePrefix)
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case strings.HasPrefix(key, counterPrefix):
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typ = "counter"
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key = strings.TrimPrefix(key, counterPrefix)
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}
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if strings.HasPrefix(key, labelMapPrefix) {
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key = strings.TrimPrefix(key, labelMapPrefix)
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if a, b, ok := strings.Cut(key, "_"); ok {
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label, key = a, b
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}
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}
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d := &prometheusMetricDetails{
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Name: strings.ReplaceAll(prefix+key, "-", "_"),
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Type: typ,
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Label: label,
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}
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prometheusMetricCache.Store(cachekey, d)
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return d.Name, d.Type, d.Label
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}
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func writePromExpVar(w io.Writer, prefix string, kv expvar.KeyValue) {
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key := kv.Key
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name, typ, label := prometheusMetric(prefix, key)
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switch v := kv.Value.(type) {
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case *expvar.Int:
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if typ == "" {
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typ = "counter"
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}
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fmt.Fprintf(w, "# TYPE %s %s\n%s %v\n", name, typ, name, v.Value())
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return
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case *expvar.Float:
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if typ == "" {
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typ = "gauge"
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}
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fmt.Fprintf(w, "# TYPE %s %s\n%s %v\n", name, typ, name, v.Value())
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return
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case *metrics.Set:
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v.Do(func(kv expvar.KeyValue) {
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writePromExpVar(w, name+"_", kv)
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})
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return
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case PrometheusMetricsReflectRooter:
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root := v.PrometheusMetricsReflectRoot()
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rv := reflect.ValueOf(root)
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if rv.Type().Kind() == reflect.Ptr {
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if rv.IsNil() {
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return
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}
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rv = rv.Elem()
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}
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if rv.Type().Kind() != reflect.Struct {
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fmt.Fprintf(w, "# skipping expvar %q; unknown root type\n", name)
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return
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}
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foreachExportedStructField(rv, func(fieldOrJSONName, metricType string, rv reflect.Value) {
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mname := name + "_" + fieldOrJSONName
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switch rv.Kind() {
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case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
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fmt.Fprintf(w, "# TYPE %s %s\n%s %v\n", mname, metricType, mname, rv.Int())
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case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
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fmt.Fprintf(w, "# TYPE %s %s\n%s %v\n", mname, metricType, mname, rv.Uint())
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case reflect.Float32, reflect.Float64:
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fmt.Fprintf(w, "# TYPE %s %s\n%s %v\n", mname, metricType, mname, rv.Float())
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case reflect.Struct:
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if rv.CanAddr() {
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// Slight optimization, not copying big structs if they're addressable:
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writePromExpVar(w, name+"_", expvar.KeyValue{Key: fieldOrJSONName, Value: expVarPromStructRoot{rv.Addr().Interface()}})
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} else {
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writePromExpVar(w, name+"_", expvar.KeyValue{Key: fieldOrJSONName, Value: expVarPromStructRoot{rv.Interface()}})
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}
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}
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return
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})
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return
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}
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if typ == "" {
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var funcRet string
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if f, ok := kv.Value.(expvar.Func); ok {
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v := f()
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if ms, ok := v.(runtime.MemStats); ok && name == "memstats" {
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writeMemstats(w, &ms)
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return
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}
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if vs, ok := v.(string); ok && strings.HasSuffix(name, "version") {
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fmt.Fprintf(w, "%s{version=%q} 1\n", name, vs)
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return
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}
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switch v := v.(type) {
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case int, int8, int16, int32, int64, uint, uint8, uint16, uint32, uint64, uintptr, float32, float64:
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fmt.Fprintf(w, "%s %v\n", name, v)
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return
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}
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funcRet = fmt.Sprintf(" returning %T", v)
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}
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switch kv.Value.(type) {
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default:
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fmt.Fprintf(w, "# skipping expvar %q (Go type %T%s) with undeclared Prometheus type\n", name, kv.Value, funcRet)
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return
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case *metrics.LabelMap, *expvar.Map:
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// Permit typeless LabelMap and expvar.Map for
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// compatibility with old expvar-registered
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// metrics.LabelMap.
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}
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}
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switch v := kv.Value.(type) {
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case expvar.Func:
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val := v()
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switch val.(type) {
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case float64, int64, int:
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fmt.Fprintf(w, "# TYPE %s %s\n%s %v\n", name, typ, name, val)
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default:
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fmt.Fprintf(w, "# skipping expvar func %q returning unknown type %T\n", name, val)
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}
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case *metrics.LabelMap:
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if typ != "" {
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fmt.Fprintf(w, "# TYPE %s %s\n", name, typ)
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}
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// IntMap uses expvar.Map on the inside, which presorts
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// keys. The output ordering is deterministic.
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v.Do(func(kv expvar.KeyValue) {
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fmt.Fprintf(w, "%s{%s=%q} %v\n", name, v.Label, kv.Key, kv.Value)
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})
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case *expvar.Map:
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if label != "" && typ != "" {
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fmt.Fprintf(w, "# TYPE %s %s\n", name, typ)
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v.Do(func(kv expvar.KeyValue) {
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fmt.Fprintf(w, "%s{%s=%q} %v\n", name, label, kv.Key, kv.Value)
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})
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} else {
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v.Do(func(kv expvar.KeyValue) {
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fmt.Fprintf(w, "%s_%s %v\n", name, kv.Key, kv.Value)
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})
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}
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}
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}
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var sortedKVsPool = &sync.Pool{New: func() any { return new(sortedKVs) }}
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// sortedKV is a KeyValue with a sort key.
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type sortedKV struct {
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expvar.KeyValue
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sortKey string // KeyValue.Key with type prefix removed
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}
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type sortedKVs struct {
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kvs []sortedKV
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}
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// Handler is an HTTP handler to write expvar values into the
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// prometheus export format:
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//
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// https://github.com/prometheus/docs/blob/master/content/docs/instrumenting/exposition_formats.md
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//
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// It makes the following assumptions:
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//
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// - *expvar.Int are counters (unless marked as a gauge_; see below)
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// - a *tailscale/metrics.Set is descended into, joining keys with
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// underscores. So use underscores as your metric names.
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// - an expvar named starting with "gauge_" or "counter_" is of that
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// Prometheus type, and has that prefix stripped.
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// - anything else is untyped and thus not exported.
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// - expvar.Func can return an int or int64 (for now) and anything else
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// is not exported.
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//
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// This will evolve over time, or perhaps be replaced.
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func Handler(w http.ResponseWriter, r *http.Request) {
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w.Header().Set("Content-Type", "text/plain; version=0.0.4")
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s := sortedKVsPool.Get().(*sortedKVs)
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defer sortedKVsPool.Put(s)
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s.kvs = s.kvs[:0]
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expvarDo(func(kv expvar.KeyValue) {
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s.kvs = append(s.kvs, sortedKV{kv, removeTypePrefixes(kv.Key)})
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})
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sort.Slice(s.kvs, func(i, j int) bool {
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return s.kvs[i].sortKey < s.kvs[j].sortKey
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})
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for _, e := range s.kvs {
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writePromExpVar(w, "", e.KeyValue)
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}
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}
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// PrometheusMetricsReflectRooter is an optional interface that expvar.Var implementations
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// can implement to indicate that they should be walked recursively with reflect to find
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// sets of fields to export.
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type PrometheusMetricsReflectRooter interface {
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expvar.Var
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// PrometheusMetricsReflectRoot returns the struct or struct pointer to walk.
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PrometheusMetricsReflectRoot() any
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}
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var expvarDo = expvar.Do // pulled out for tests
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func writeMemstats(w io.Writer, ms *runtime.MemStats) {
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out := func(name, typ string, v uint64, help string) {
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if help != "" {
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fmt.Fprintf(w, "# HELP memstats_%s %s\n", name, help)
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}
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fmt.Fprintf(w, "# TYPE memstats_%s %s\nmemstats_%s %v\n", name, typ, name, v)
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}
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g := func(name string, v uint64, help string) { out(name, "gauge", v, help) }
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||||||
|
c := func(name string, v uint64, help string) { out(name, "counter", v, help) }
|
||||||
|
g("heap_alloc", ms.HeapAlloc, "current bytes of allocated heap objects (up/down smoothly)")
|
||||||
|
c("total_alloc", ms.TotalAlloc, "cumulative bytes allocated for heap objects")
|
||||||
|
g("sys", ms.Sys, "total bytes of memory obtained from the OS")
|
||||||
|
c("mallocs", ms.Mallocs, "cumulative count of heap objects allocated")
|
||||||
|
c("frees", ms.Frees, "cumulative count of heap objects freed")
|
||||||
|
c("num_gc", uint64(ms.NumGC), "number of completed GC cycles")
|
||||||
|
}
|
||||||
|
|
||||||
|
// sortedStructField is metadata about a struct field used both for sorting once
|
||||||
|
// (by structTypeSortedFields) and at serving time (by
|
||||||
|
// foreachExportedStructField).
|
||||||
|
type sortedStructField struct {
|
||||||
|
Index int // index of struct field in struct
|
||||||
|
Name string // struct field name, or "json" name
|
||||||
|
SortName string // Name with "foo_" type prefixes removed
|
||||||
|
MetricType string // the "metrictype" struct tag
|
||||||
|
StructFieldType *reflect.StructField
|
||||||
|
}
|
||||||
|
|
||||||
|
var structSortedFieldsCache sync.Map // reflect.Type => []sortedStructField
|
||||||
|
|
||||||
|
// structTypeSortedFields returns the sorted fields of t, caching as needed.
|
||||||
|
func structTypeSortedFields(t reflect.Type) []sortedStructField {
|
||||||
|
if v, ok := structSortedFieldsCache.Load(t); ok {
|
||||||
|
return v.([]sortedStructField)
|
||||||
|
}
|
||||||
|
fields := make([]sortedStructField, 0, t.NumField())
|
||||||
|
for i, n := 0, t.NumField(); i < n; i++ {
|
||||||
|
sf := t.Field(i)
|
||||||
|
name := sf.Name
|
||||||
|
if v := sf.Tag.Get("json"); v != "" {
|
||||||
|
v, _, _ = strings.Cut(v, ",")
|
||||||
|
if v == "-" {
|
||||||
|
// Skip it, regardless of its metrictype.
|
||||||
|
continue
|
||||||
|
}
|
||||||
|
if v != "" {
|
||||||
|
name = v
|
||||||
|
}
|
||||||
|
}
|
||||||
|
fields = append(fields, sortedStructField{
|
||||||
|
Index: i,
|
||||||
|
Name: name,
|
||||||
|
SortName: removeTypePrefixes(name),
|
||||||
|
MetricType: sf.Tag.Get("metrictype"),
|
||||||
|
StructFieldType: &sf,
|
||||||
|
})
|
||||||
|
}
|
||||||
|
sort.Slice(fields, func(i, j int) bool {
|
||||||
|
return fields[i].SortName < fields[j].SortName
|
||||||
|
})
|
||||||
|
structSortedFieldsCache.Store(t, fields)
|
||||||
|
return fields
|
||||||
|
}
|
||||||
|
|
||||||
|
// removeTypePrefixes returns s with the first "foo_" prefix in prefixesToTrim
|
||||||
|
// removed.
|
||||||
|
func removeTypePrefixes(s string) string {
|
||||||
|
for _, prefix := range prefixesToTrim {
|
||||||
|
if trimmed, ok := strings.CutPrefix(s, prefix); ok {
|
||||||
|
return trimmed
|
||||||
|
}
|
||||||
|
}
|
||||||
|
return s
|
||||||
|
}
|
||||||
|
|
||||||
|
// foreachExportedStructField iterates over the fields in sorted order of
|
||||||
|
// their name, after removing metric prefixes. This is not necessarily the
|
||||||
|
// order they were declared in the struct
|
||||||
|
func foreachExportedStructField(rv reflect.Value, f func(fieldOrJSONName, metricType string, rv reflect.Value)) {
|
||||||
|
t := rv.Type()
|
||||||
|
for _, ssf := range structTypeSortedFields(t) {
|
||||||
|
sf := ssf.StructFieldType
|
||||||
|
if ssf.MetricType != "" || sf.Type.Kind() == reflect.Struct {
|
||||||
|
f(ssf.Name, ssf.MetricType, rv.Field(ssf.Index))
|
||||||
|
} else if sf.Type.Kind() == reflect.Ptr && sf.Type.Elem().Kind() == reflect.Struct {
|
||||||
|
fv := rv.Field(ssf.Index)
|
||||||
|
if !fv.IsNil() {
|
||||||
|
f(ssf.Name, ssf.MetricType, fv.Elem())
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
type expVarPromStructRoot struct{ v any }
|
||||||
|
|
||||||
|
func (r expVarPromStructRoot) PrometheusMetricsReflectRoot() any { return r.v }
|
||||||
|
func (r expVarPromStructRoot) String() string { panic("unused") }
|
||||||
|
|
||||||
|
var (
|
||||||
|
_ PrometheusMetricsReflectRooter = expVarPromStructRoot{}
|
||||||
|
_ expvar.Var = expVarPromStructRoot{}
|
||||||
|
)
|
||||||
@ -0,0 +1,375 @@
|
|||||||
|
// Copyright (c) Tailscale Inc & AUTHORS
|
||||||
|
// SPDX-License-Identifier: BSD-3-Clause
|
||||||
|
|
||||||
|
package varz
|
||||||
|
|
||||||
|
import (
|
||||||
|
"expvar"
|
||||||
|
"net/http/httptest"
|
||||||
|
"reflect"
|
||||||
|
"strings"
|
||||||
|
"testing"
|
||||||
|
|
||||||
|
"tailscale.com/metrics"
|
||||||
|
"tailscale.com/tstest"
|
||||||
|
"tailscale.com/version"
|
||||||
|
)
|
||||||
|
|
||||||
|
func TestVarzHandler(t *testing.T) {
|
||||||
|
t.Run("globals_log", func(t *testing.T) {
|
||||||
|
rec := httptest.NewRecorder()
|
||||||
|
Handler(rec, httptest.NewRequest("GET", "/", nil))
|
||||||
|
t.Logf("Got: %s", rec.Body.Bytes())
|
||||||
|
})
|
||||||
|
|
||||||
|
half := new(expvar.Float)
|
||||||
|
half.Set(0.5)
|
||||||
|
|
||||||
|
tests := []struct {
|
||||||
|
name string
|
||||||
|
k string // key name
|
||||||
|
v expvar.Var
|
||||||
|
want string
|
||||||
|
}{
|
||||||
|
{
|
||||||
|
"int",
|
||||||
|
"foo",
|
||||||
|
new(expvar.Int),
|
||||||
|
"# TYPE foo counter\nfoo 0\n",
|
||||||
|
},
|
||||||
|
{
|
||||||
|
"dash_in_metric_name",
|
||||||
|
"counter_foo-bar",
|
||||||
|
new(expvar.Int),
|
||||||
|
"# TYPE foo_bar counter\nfoo_bar 0\n",
|
||||||
|
},
|
||||||
|
{
|
||||||
|
"int_with_type_counter",
|
||||||
|
"counter_foo",
|
||||||
|
new(expvar.Int),
|
||||||
|
"# TYPE foo counter\nfoo 0\n",
|
||||||
|
},
|
||||||
|
{
|
||||||
|
"int_with_type_gauge",
|
||||||
|
"gauge_foo",
|
||||||
|
new(expvar.Int),
|
||||||
|
"# TYPE foo gauge\nfoo 0\n",
|
||||||
|
},
|
||||||
|
{
|
||||||
|
// For a float = 0.0, Prometheus client_golang outputs "0"
|
||||||
|
"float_zero",
|
||||||
|
"foo",
|
||||||
|
new(expvar.Float),
|
||||||
|
"# TYPE foo gauge\nfoo 0\n",
|
||||||
|
},
|
||||||
|
{
|
||||||
|
"float_point_5",
|
||||||
|
"foo",
|
||||||
|
half,
|
||||||
|
"# TYPE foo gauge\nfoo 0.5\n",
|
||||||
|
},
|
||||||
|
{
|
||||||
|
"float_with_type_counter",
|
||||||
|
"counter_foo",
|
||||||
|
half,
|
||||||
|
"# TYPE foo counter\nfoo 0.5\n",
|
||||||
|
},
|
||||||
|
{
|
||||||
|
"float_with_type_gauge",
|
||||||
|
"gauge_foo",
|
||||||
|
half,
|
||||||
|
"# TYPE foo gauge\nfoo 0.5\n",
|
||||||
|
},
|
||||||
|
{
|
||||||
|
"metrics_set",
|
||||||
|
"s",
|
||||||
|
&metrics.Set{
|
||||||
|
Map: *(func() *expvar.Map {
|
||||||
|
m := new(expvar.Map)
|
||||||
|
m.Init()
|
||||||
|
m.Add("foo", 1)
|
||||||
|
m.Add("bar", 2)
|
||||||
|
return m
|
||||||
|
})(),
|
||||||
|
},
|
||||||
|
"# TYPE s_bar counter\ns_bar 2\n# TYPE s_foo counter\ns_foo 1\n",
|
||||||
|
},
|
||||||
|
{
|
||||||
|
"metrics_set_TODO_gauge_type",
|
||||||
|
"gauge_s", // TODO(bradfitz): arguably a bug; should pass down type
|
||||||
|
&metrics.Set{
|
||||||
|
Map: *(func() *expvar.Map {
|
||||||
|
m := new(expvar.Map)
|
||||||
|
m.Init()
|
||||||
|
m.Add("foo", 1)
|
||||||
|
m.Add("bar", 2)
|
||||||
|
return m
|
||||||
|
})(),
|
||||||
|
},
|
||||||
|
"# TYPE s_bar counter\ns_bar 2\n# TYPE s_foo counter\ns_foo 1\n",
|
||||||
|
},
|
||||||
|
{
|
||||||
|
"expvar_map_untyped",
|
||||||
|
"api_status_code",
|
||||||
|
func() *expvar.Map {
|
||||||
|
m := new(expvar.Map)
|
||||||
|
m.Init()
|
||||||
|
m.Add("2xx", 100)
|
||||||
|
m.Add("5xx", 2)
|
||||||
|
return m
|
||||||
|
}(),
|
||||||
|
"api_status_code_2xx 100\napi_status_code_5xx 2\n",
|
||||||
|
},
|
||||||
|
{
|
||||||
|
"func_float64",
|
||||||
|
"counter_x",
|
||||||
|
expvar.Func(func() any { return float64(1.2) }),
|
||||||
|
"# TYPE x counter\nx 1.2\n",
|
||||||
|
},
|
||||||
|
{
|
||||||
|
"func_float64_gauge",
|
||||||
|
"gauge_y",
|
||||||
|
expvar.Func(func() any { return float64(1.2) }),
|
||||||
|
"# TYPE y gauge\ny 1.2\n",
|
||||||
|
},
|
||||||
|
{
|
||||||
|
"func_float64_untyped",
|
||||||
|
"z",
|
||||||
|
expvar.Func(func() any { return float64(1.2) }),
|
||||||
|
"z 1.2\n",
|
||||||
|
},
|
||||||
|
{
|
||||||
|
"metrics_label_map",
|
||||||
|
"counter_m",
|
||||||
|
&metrics.LabelMap{
|
||||||
|
Label: "label",
|
||||||
|
Map: *(func() *expvar.Map {
|
||||||
|
m := new(expvar.Map)
|
||||||
|
m.Init()
|
||||||
|
m.Add("foo", 1)
|
||||||
|
m.Add("bar", 2)
|
||||||
|
return m
|
||||||
|
})(),
|
||||||
|
},
|
||||||
|
"# TYPE m counter\nm{label=\"bar\"} 2\nm{label=\"foo\"} 1\n",
|
||||||
|
},
|
||||||
|
{
|
||||||
|
"metrics_label_map_untyped",
|
||||||
|
"control_save_config",
|
||||||
|
(func() *metrics.LabelMap {
|
||||||
|
m := &metrics.LabelMap{Label: "reason"}
|
||||||
|
m.Add("new", 1)
|
||||||
|
m.Add("updated", 1)
|
||||||
|
m.Add("fun", 1)
|
||||||
|
return m
|
||||||
|
})(),
|
||||||
|
"control_save_config{reason=\"fun\"} 1\ncontrol_save_config{reason=\"new\"} 1\ncontrol_save_config{reason=\"updated\"} 1\n",
|
||||||
|
},
|
||||||
|
{
|
||||||
|
"expvar_label_map",
|
||||||
|
"counter_labelmap_keyname_m",
|
||||||
|
func() *expvar.Map {
|
||||||
|
m := new(expvar.Map)
|
||||||
|
m.Init()
|
||||||
|
m.Add("foo", 1)
|
||||||
|
m.Add("bar", 2)
|
||||||
|
return m
|
||||||
|
}(),
|
||||||
|
"# TYPE m counter\nm{keyname=\"bar\"} 2\nm{keyname=\"foo\"} 1\n",
|
||||||
|
},
|
||||||
|
{
|
||||||
|
"struct_reflect",
|
||||||
|
"foo",
|
||||||
|
someExpVarWithJSONAndPromTypes(),
|
||||||
|
strings.TrimSpace(`
|
||||||
|
# TYPE foo_AUint16 counter
|
||||||
|
foo_AUint16 65535
|
||||||
|
# TYPE foo_AnInt8 counter
|
||||||
|
foo_AnInt8 127
|
||||||
|
# TYPE foo_curTemp gauge
|
||||||
|
foo_curTemp 20.6
|
||||||
|
# TYPE foo_curX gauge
|
||||||
|
foo_curX 3
|
||||||
|
# TYPE foo_nestptr_bar counter
|
||||||
|
foo_nestptr_bar 20
|
||||||
|
# TYPE foo_nestptr_foo gauge
|
||||||
|
foo_nestptr_foo 10
|
||||||
|
# TYPE foo_nestvalue_bar counter
|
||||||
|
foo_nestvalue_bar 2
|
||||||
|
# TYPE foo_nestvalue_foo gauge
|
||||||
|
foo_nestvalue_foo 1
|
||||||
|
# TYPE foo_totalY counter
|
||||||
|
foo_totalY 4
|
||||||
|
`) + "\n",
|
||||||
|
},
|
||||||
|
{
|
||||||
|
"struct_reflect_nil_root",
|
||||||
|
"foo",
|
||||||
|
expvarAdapter{(*SomeStats)(nil)},
|
||||||
|
"",
|
||||||
|
},
|
||||||
|
{
|
||||||
|
"func_returning_int",
|
||||||
|
"num_goroutines",
|
||||||
|
expvar.Func(func() any { return 123 }),
|
||||||
|
"num_goroutines 123\n",
|
||||||
|
},
|
||||||
|
{
|
||||||
|
"string_version_var",
|
||||||
|
"foo_version",
|
||||||
|
expvar.Func(func() any { return "1.2.3-foo15" }),
|
||||||
|
"foo_version{version=\"1.2.3-foo15\"} 1\n",
|
||||||
|
},
|
||||||
|
{
|
||||||
|
"field_ordering",
|
||||||
|
"foo",
|
||||||
|
someExpVarWithFieldNamesSorting(),
|
||||||
|
strings.TrimSpace(`
|
||||||
|
# TYPE foo_bar_a gauge
|
||||||
|
foo_bar_a 1
|
||||||
|
# TYPE foo_bar_b counter
|
||||||
|
foo_bar_b 1
|
||||||
|
# TYPE foo_foo_a gauge
|
||||||
|
foo_foo_a 1
|
||||||
|
# TYPE foo_foo_b counter
|
||||||
|
foo_foo_b 1
|
||||||
|
`) + "\n",
|
||||||
|
},
|
||||||
|
}
|
||||||
|
for _, tt := range tests {
|
||||||
|
t.Run(tt.name, func(t *testing.T) {
|
||||||
|
tstest.Replace(t, &expvarDo, func(f func(expvar.KeyValue)) {
|
||||||
|
f(expvar.KeyValue{Key: tt.k, Value: tt.v})
|
||||||
|
})
|
||||||
|
rec := httptest.NewRecorder()
|
||||||
|
Handler(rec, httptest.NewRequest("GET", "/", nil))
|
||||||
|
if got := rec.Body.Bytes(); string(got) != tt.want {
|
||||||
|
t.Errorf("mismatch\n got: %q\n%s\nwant: %q\n%s\n", got, got, tt.want, tt.want)
|
||||||
|
}
|
||||||
|
})
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
type SomeNested struct {
|
||||||
|
FooG int64 `json:"foo" metrictype:"gauge"`
|
||||||
|
BarC int64 `json:"bar" metrictype:"counter"`
|
||||||
|
Omit int `json:"-" metrictype:"counter"`
|
||||||
|
}
|
||||||
|
|
||||||
|
type SomeStats struct {
|
||||||
|
Nested SomeNested `json:"nestvalue"`
|
||||||
|
NestedPtr *SomeNested `json:"nestptr"`
|
||||||
|
NestedNilPtr *SomeNested `json:"nestnilptr"`
|
||||||
|
CurX int `json:"curX" metrictype:"gauge"`
|
||||||
|
NoMetricType int `json:"noMetric" metrictype:""`
|
||||||
|
TotalY int64 `json:"totalY,omitempty" metrictype:"counter"`
|
||||||
|
CurTemp float64 `json:"curTemp" metrictype:"gauge"`
|
||||||
|
AnInt8 int8 `metrictype:"counter"`
|
||||||
|
AUint16 uint16 `metrictype:"counter"`
|
||||||
|
}
|
||||||
|
|
||||||
|
// someExpVarWithJSONAndPromTypes returns an expvar.Var that
|
||||||
|
// implements PrometheusMetricsReflectRooter for TestVarzHandler.
|
||||||
|
func someExpVarWithJSONAndPromTypes() expvar.Var {
|
||||||
|
st := &SomeStats{
|
||||||
|
Nested: SomeNested{
|
||||||
|
FooG: 1,
|
||||||
|
BarC: 2,
|
||||||
|
Omit: 3,
|
||||||
|
},
|
||||||
|
NestedPtr: &SomeNested{
|
||||||
|
FooG: 10,
|
||||||
|
BarC: 20,
|
||||||
|
},
|
||||||
|
CurX: 3,
|
||||||
|
TotalY: 4,
|
||||||
|
CurTemp: 20.6,
|
||||||
|
AnInt8: 127,
|
||||||
|
AUint16: 65535,
|
||||||
|
}
|
||||||
|
return expvarAdapter{st}
|
||||||
|
}
|
||||||
|
|
||||||
|
type expvarAdapter struct {
|
||||||
|
st *SomeStats
|
||||||
|
}
|
||||||
|
|
||||||
|
func (expvarAdapter) String() string { return "{}" } // expvar JSON; unused in test
|
||||||
|
|
||||||
|
func (a expvarAdapter) PrometheusMetricsReflectRoot() any {
|
||||||
|
return a.st
|
||||||
|
}
|
||||||
|
|
||||||
|
// SomeTestOfFieldNamesSorting demonstrates field
|
||||||
|
// names that are not in sorted in declaration order, to verify
|
||||||
|
// that we sort based on field name
|
||||||
|
type SomeTestOfFieldNamesSorting struct {
|
||||||
|
FooAG int64 `json:"foo_a" metrictype:"gauge"`
|
||||||
|
BarAG int64 `json:"bar_a" metrictype:"gauge"`
|
||||||
|
FooBC int64 `json:"foo_b" metrictype:"counter"`
|
||||||
|
BarBC int64 `json:"bar_b" metrictype:"counter"`
|
||||||
|
}
|
||||||
|
|
||||||
|
// someExpVarWithFieldNamesSorting returns an expvar.Var that
|
||||||
|
// implements PrometheusMetricsReflectRooter for TestVarzHandler.
|
||||||
|
func someExpVarWithFieldNamesSorting() expvar.Var {
|
||||||
|
st := &SomeTestOfFieldNamesSorting{
|
||||||
|
FooAG: 1,
|
||||||
|
BarAG: 1,
|
||||||
|
FooBC: 1,
|
||||||
|
BarBC: 1,
|
||||||
|
}
|
||||||
|
return expvarAdapter2{st}
|
||||||
|
}
|
||||||
|
|
||||||
|
type expvarAdapter2 struct {
|
||||||
|
st *SomeTestOfFieldNamesSorting
|
||||||
|
}
|
||||||
|
|
||||||
|
func (expvarAdapter2) String() string { return "{}" } // expvar JSON; unused in test
|
||||||
|
|
||||||
|
func (a expvarAdapter2) PrometheusMetricsReflectRoot() any {
|
||||||
|
return a.st
|
||||||
|
}
|
||||||
|
|
||||||
|
func TestSortedStructAllocs(t *testing.T) {
|
||||||
|
f := reflect.ValueOf(struct {
|
||||||
|
Foo int
|
||||||
|
Bar int
|
||||||
|
Baz int
|
||||||
|
}{})
|
||||||
|
n := testing.AllocsPerRun(1000, func() {
|
||||||
|
foreachExportedStructField(f, func(fieldOrJSONName, metricType string, rv reflect.Value) {
|
||||||
|
// Nothing.
|
||||||
|
})
|
||||||
|
})
|
||||||
|
if n != 0 {
|
||||||
|
t.Errorf("allocs = %v; want 0", n)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
func TestVarzHandlerSorting(t *testing.T) {
|
||||||
|
tstest.Replace(t, &expvarDo, func(f func(expvar.KeyValue)) {
|
||||||
|
f(expvar.KeyValue{Key: "counter_zz", Value: new(expvar.Int)})
|
||||||
|
f(expvar.KeyValue{Key: "gauge_aa", Value: new(expvar.Int)})
|
||||||
|
})
|
||||||
|
rec := httptest.NewRecorder()
|
||||||
|
req := httptest.NewRequest("GET", "/", nil)
|
||||||
|
Handler(rec, req)
|
||||||
|
got := rec.Body.Bytes()
|
||||||
|
const want = "# TYPE aa gauge\naa 0\n# TYPE zz counter\nzz 0\n"
|
||||||
|
if string(got) != want {
|
||||||
|
t.Errorf("got %q; want %q", got, want)
|
||||||
|
}
|
||||||
|
rec = new(httptest.ResponseRecorder) // without a body
|
||||||
|
|
||||||
|
// Lock in the current number of allocs, to prevent it from growing.
|
||||||
|
if !version.IsRace() {
|
||||||
|
allocs := int(testing.AllocsPerRun(1000, func() {
|
||||||
|
Handler(rec, req)
|
||||||
|
}))
|
||||||
|
if max := 13; allocs > max {
|
||||||
|
t.Errorf("allocs = %v; want max %v", allocs, max)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
Loading…
Reference in New Issue