mirror of https://github.com/tailscale/tailscale/
usermetric: add initial user-facing metrics
This commit adds a new usermetric package and wires up metrics across the tailscale client. Updates tailscale/corp#22075 Co-authored-by: Anton Tolchanov <anton@tailscale.com> Signed-off-by: Kristoffer Dalby <kristoffer@tailscale.com>jwhited/test-local-forwarder
Kristoffer Dalby
3 months ago
committed by
Kristoffer Dalby
parent
06c31f4e91
commit
a2c42d3cd4
@ -0,0 +1,84 @@
|
|||||||
|
// Copyright (c) Tailscale Inc & AUTHORS
|
||||||
|
// SPDX-License-Identifier: BSD-3-Clause
|
||||||
|
|
||||||
|
// Package usermetric provides a container and handler
|
||||||
|
// for user-facing metrics.
|
||||||
|
package usermetric
|
||||||
|
|
||||||
|
import (
|
||||||
|
"expvar"
|
||||||
|
"fmt"
|
||||||
|
"io"
|
||||||
|
"net/http"
|
||||||
|
|
||||||
|
"tailscale.com/metrics"
|
||||||
|
"tailscale.com/tsweb/varz"
|
||||||
|
)
|
||||||
|
|
||||||
|
var vars expvar.Map
|
||||||
|
|
||||||
|
// NewMultiLabelMap creates and register a new
|
||||||
|
// MultiLabelMap[T] variable with the given name and returns it.
|
||||||
|
// The variable is registered with the userfacing metrics package.
|
||||||
|
//
|
||||||
|
// Note that usermetric are not protected against duplicate
|
||||||
|
// metrics name. It is the caller's responsibility to ensure that
|
||||||
|
// the name is unique.
|
||||||
|
func NewMultiLabelMap[T comparable](name string, promType, helpText string) *metrics.MultiLabelMap[T] {
|
||||||
|
m := &metrics.MultiLabelMap[T]{
|
||||||
|
Type: promType,
|
||||||
|
Help: helpText,
|
||||||
|
}
|
||||||
|
var zero T
|
||||||
|
_ = metrics.LabelString(zero) // panic early if T is invalid
|
||||||
|
vars.Set(name, m)
|
||||||
|
return m
|
||||||
|
}
|
||||||
|
|
||||||
|
// Gauge is a gauge metric with no labels.
|
||||||
|
type Gauge struct {
|
||||||
|
m *expvar.Float
|
||||||
|
help string
|
||||||
|
}
|
||||||
|
|
||||||
|
// NewGauge creates and register a new gauge metric with the given name and help text.
|
||||||
|
func NewGauge(name, help string) *Gauge {
|
||||||
|
g := &Gauge{&expvar.Float{}, help}
|
||||||
|
vars.Set(name, g)
|
||||||
|
return g
|
||||||
|
}
|
||||||
|
|
||||||
|
// Set sets the gauge to the given value.
|
||||||
|
func (g *Gauge) Set(v float64) {
|
||||||
|
g.m.Set(v)
|
||||||
|
}
|
||||||
|
|
||||||
|
// String returns the string of the underlying expvar.Float.
|
||||||
|
// This satisfies the expvar.Var interface.
|
||||||
|
func (g *Gauge) String() string {
|
||||||
|
return g.m.String()
|
||||||
|
}
|
||||||
|
|
||||||
|
// WritePrometheus writes the gauge metric in Prometheus format to the given writer.
|
||||||
|
// This satisfies the varz.PrometheusWriter interface.
|
||||||
|
func (g *Gauge) WritePrometheus(w io.Writer, name string) {
|
||||||
|
io.WriteString(w, "# TYPE ")
|
||||||
|
io.WriteString(w, name)
|
||||||
|
io.WriteString(w, " gauge\n")
|
||||||
|
if g.help != "" {
|
||||||
|
io.WriteString(w, "# HELP ")
|
||||||
|
io.WriteString(w, name)
|
||||||
|
io.WriteString(w, " ")
|
||||||
|
io.WriteString(w, g.help)
|
||||||
|
io.WriteString(w, "\n")
|
||||||
|
}
|
||||||
|
|
||||||
|
io.WriteString(w, name)
|
||||||
|
fmt.Fprintf(w, " %v\n", g.m.Value())
|
||||||
|
}
|
||||||
|
|
||||||
|
// Handler returns a varz.Handler that serves the userfacing expvar contained
|
||||||
|
// in this package.
|
||||||
|
func Handler(w http.ResponseWriter, r *http.Request) {
|
||||||
|
varz.ExpvarDoHandler(vars.Do)(w, r)
|
||||||
|
}
|
||||||
@ -0,0 +1,25 @@
|
|||||||
|
// Copyright (c) Tailscale Inc & AUTHORS
|
||||||
|
// SPDX-License-Identifier: BSD-3-Clause
|
||||||
|
|
||||||
|
package usermetric
|
||||||
|
|
||||||
|
import (
|
||||||
|
"bytes"
|
||||||
|
"testing"
|
||||||
|
)
|
||||||
|
|
||||||
|
func TestGauge(t *testing.T) {
|
||||||
|
g := NewGauge("test_gauge", "This is a test gauge")
|
||||||
|
g.Set(15)
|
||||||
|
|
||||||
|
var buf bytes.Buffer
|
||||||
|
g.WritePrometheus(&buf, "test_gauge")
|
||||||
|
const want = `# TYPE test_gauge gauge
|
||||||
|
# HELP test_gauge This is a test gauge
|
||||||
|
test_gauge 15
|
||||||
|
`
|
||||||
|
if got := buf.String(); got != want {
|
||||||
|
t.Errorf("got %q; want %q", got, want)
|
||||||
|
}
|
||||||
|
|
||||||
|
}
|
||||||
Loading…
Reference in New Issue