tailscale/metrics/multilabelmap_test.go

151 lines
3.2 KiB
Go

// Copyright (c) Tailscale Inc & AUTHORS
// SPDX-License-Identifier: BSD-3-Clause
package metrics
import (
"bytes"
"encoding/json"
"expvar"
"fmt"
"io"
"testing"
)
type L2 struct {
Foo string `prom:"foo"`
Bar string `prom:"bar"`
}
func TestMultilabelMap(t *testing.T) {
m := new(MultiLabelMap[L2])
m.Add(L2{"a", "b"}, 2)
m.Add(L2{"b", "c"}, 4)
m.Add(L2{"b", "b"}, 3)
m.Add(L2{"a", "a"}, 1)
m.SetFloat(L2{"sf", "sf"}, 3.5)
m.SetFloat(L2{"sf", "sf"}, 5.5)
m.Set(L2{"sfunc", "sfunc"}, expvar.Func(func() any { return 3 }))
m.SetInt(L2{"si", "si"}, 3)
m.SetInt(L2{"si", "si"}, 5)
cur := func() string {
var buf bytes.Buffer
m.Do(func(kv KeyValue[L2]) {
if buf.Len() > 0 {
buf.WriteString(",")
}
fmt.Fprintf(&buf, "%s/%s=%v", kv.Key.Foo, kv.Key.Bar, kv.Value)
})
return buf.String()
}
if g, w := cur(), "a/a=1,a/b=2,b/b=3,b/c=4,sf/sf=5.5,sfunc/sfunc=3,si/si=5"; g != w {
t.Errorf("got %q; want %q", g, w)
}
var buf bytes.Buffer
m.WritePrometheus(&buf, "metricname")
const want = `metricname{foo="a",bar="a"} 1
metricname{foo="a",bar="b"} 2
metricname{foo="b",bar="b"} 3
metricname{foo="b",bar="c"} 4
metricname{foo="sf",bar="sf"} 5.5
metricname{foo="sfunc",bar="sfunc"} 3
metricname{foo="si",bar="si"} 5
`
if got := buf.String(); got != want {
t.Errorf("promtheus output = %q; want %q", got, want)
}
m.Delete(L2{"b", "b"})
if g, w := cur(), "a/a=1,a/b=2,b/c=4,sf/sf=5.5,sfunc/sfunc=3,si/si=5"; g != w {
t.Errorf("got %q; want %q", g, w)
}
allocs := testing.AllocsPerRun(1000, func() {
m.Add(L2{"a", "a"}, 1)
})
if allocs > 0 {
t.Errorf("allocs = %v; want 0", allocs)
}
m.Init()
if g, w := cur(), ""; g != w {
t.Errorf("got %q; want %q", g, w)
}
writeAllocs := testing.AllocsPerRun(1000, func() {
m.WritePrometheus(io.Discard, "test")
})
if writeAllocs > 0 {
t.Errorf("writeAllocs = %v; want 0", writeAllocs)
}
}
func TestMultiLabelMapTypes(t *testing.T) {
type LabelTypes struct {
S string
B bool
I int
U uint
}
m := new(MultiLabelMap[LabelTypes])
m.Type = "counter"
m.Help = "some good stuff"
m.Add(LabelTypes{"a", true, -1, 2}, 3)
var buf bytes.Buffer
m.WritePrometheus(&buf, "metricname")
const want = `# TYPE metricname counter
# HELP metricname some good stuff
metricname{s="a",b="true",i="-1",u="2"} 3
`
if got := buf.String(); got != want {
t.Errorf("got %q; want %q", got, want)
}
writeAllocs := testing.AllocsPerRun(1000, func() {
m.WritePrometheus(io.Discard, "test")
})
if writeAllocs > 0 {
t.Errorf("writeAllocs = %v; want 0", writeAllocs)
}
}
func BenchmarkMultiLabelWriteAllocs(b *testing.B) {
b.ReportAllocs()
m := new(MultiLabelMap[L2])
m.Add(L2{"a", "b"}, 2)
m.Add(L2{"b", "c"}, 4)
m.Add(L2{"b", "b"}, 3)
m.Add(L2{"a", "a"}, 1)
var w io.Writer = io.Discard
b.ResetTimer()
for range b.N {
m.WritePrometheus(w, "test")
}
}
func TestMultiLabelMapExpvar(t *testing.T) {
m := new(MultiLabelMap[L2])
m.Add(L2{"a", "b"}, 2)
m.Add(L2{"b", "c"}, 4)
em := new(expvar.Map)
em.Set("multi", m)
// Ensure that the String method is valid JSON to ensure that it can be
// used by expvar.
encoded := []byte(em.String())
if !json.Valid(encoded) {
t.Fatalf("invalid JSON: %s", encoded)
}
t.Logf("em = %+v", em)
}