You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
prometheus/scrape/scrape_test.go

3844 lines
111 KiB

// Copyright 2016 The Prometheus 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 scrape
import (
"bytes"
"compress/gzip"
"context"
"encoding/binary"
"errors"
"fmt"
"io"
"math"
"net/http"
"net/http/httptest"
"net/url"
"strconv"
"strings"
"sync"
"testing"
"time"
"github.com/go-kit/log"
"github.com/gogo/protobuf/proto"
"github.com/google/go-cmp/cmp"
"github.com/prometheus/client_golang/prometheus"
prom_testutil "github.com/prometheus/client_golang/prometheus/testutil"
dto "github.com/prometheus/client_model/go"
config_util "github.com/prometheus/common/config"
"github.com/prometheus/common/model"
"github.com/stretchr/testify/require"
"github.com/prometheus/prometheus/config"
"github.com/prometheus/prometheus/discovery"
"github.com/prometheus/prometheus/discovery/targetgroup"
"github.com/prometheus/prometheus/model/exemplar"
"github.com/prometheus/prometheus/model/histogram"
"github.com/prometheus/prometheus/model/labels"
"github.com/prometheus/prometheus/model/relabel"
"github.com/prometheus/prometheus/model/textparse"
"github.com/prometheus/prometheus/model/timestamp"
"github.com/prometheus/prometheus/model/value"
"github.com/prometheus/prometheus/storage"
"github.com/prometheus/prometheus/tsdb/chunkenc"
"github.com/prometheus/prometheus/util/pool"
"github.com/prometheus/prometheus/util/teststorage"
"github.com/prometheus/prometheus/util/testutil"
)
func TestMain(m *testing.M) {
testutil.TolerantVerifyLeak(m)
}
func newTestScrapeMetrics(t testing.TB) *scrapeMetrics {
reg := prometheus.NewRegistry()
metrics, err := newScrapeMetrics(reg)
require.NoError(t, err)
return metrics
}
func TestNewScrapePool(t *testing.T) {
var (
app = &nopAppendable{}
cfg = &config.ScrapeConfig{}
sp, _ = newScrapePool(cfg, app, 0, nil, nil, &Options{}, newTestScrapeMetrics(t))
)
a, ok := sp.appendable.(*nopAppendable)
require.True(t, ok, "Failure to append.")
require.Equal(t, app, a, "Wrong sample appender.")
require.Equal(t, cfg, sp.config, "Wrong scrape config.")
require.NotNil(t, sp.newLoop, "newLoop function not initialized.")
}
func TestDroppedTargetsList(t *testing.T) {
var (
app = &nopAppendable{}
cfg = &config.ScrapeConfig{
JobName: "dropMe",
ScrapeInterval: model.Duration(1),
RelabelConfigs: []*relabel.Config{
{
Action: relabel.Drop,
Regex: relabel.MustNewRegexp("dropMe"),
SourceLabels: model.LabelNames{"job"},
},
},
}
tgs = []*targetgroup.Group{
{
Targets: []model.LabelSet{
{model.AddressLabel: "127.0.0.1:9090"},
{model.AddressLabel: "127.0.0.1:9091"},
},
},
}
sp, _ = newScrapePool(cfg, app, 0, nil, nil, &Options{}, newTestScrapeMetrics(t))
expectedLabelSetString = "{__address__=\"127.0.0.1:9090\", __scrape_interval__=\"0s\", __scrape_timeout__=\"0s\", job=\"dropMe\"}"
expectedLength = 2
)
sp.Sync(tgs)
sp.Sync(tgs)
require.Len(t, sp.droppedTargets, expectedLength)
require.Equal(t, expectedLength, sp.droppedTargetsCount)
require.Equal(t, expectedLabelSetString, sp.droppedTargets[0].DiscoveredLabels().String())
// Check that count is still correct when we don't retain all dropped targets.
sp.config.KeepDroppedTargets = 1
sp.Sync(tgs)
require.Len(t, sp.droppedTargets, 1)
require.Equal(t, expectedLength, sp.droppedTargetsCount)
}
// TestDiscoveredLabelsUpdate checks that DiscoveredLabels are updated
// even when new labels don't affect the target `hash`.
func TestDiscoveredLabelsUpdate(t *testing.T) {
sp := &scrapePool{
metrics: newTestScrapeMetrics(t),
}
// These are used when syncing so need this to avoid a panic.
sp.config = &config.ScrapeConfig{
ScrapeInterval: model.Duration(1),
ScrapeTimeout: model.Duration(1),
}
sp.activeTargets = make(map[uint64]*Target)
t1 := &Target{
discoveredLabels: labels.FromStrings("label", "name"),
}
sp.activeTargets[t1.hash()] = t1
t2 := &Target{
discoveredLabels: labels.FromStrings("labelNew", "nameNew"),
}
sp.sync([]*Target{t2})
require.Equal(t, t2.DiscoveredLabels(), sp.activeTargets[t1.hash()].DiscoveredLabels())
}
type testLoop struct {
startFunc func(interval, timeout time.Duration, errc chan<- error)
stopFunc func()
forcedErr error
forcedErrMtx sync.Mutex
runOnce bool
interval time.Duration
timeout time.Duration
}
func (l *testLoop) setScrapeFailureLogger(log.Logger) {
}
func (l *testLoop) run(errc chan<- error) {
if l.runOnce {
panic("loop must be started only once")
}
l.runOnce = true
l.startFunc(l.interval, l.timeout, errc)
}
func (l *testLoop) disableEndOfRunStalenessMarkers() {
}
func (l *testLoop) setForcedError(err error) {
l.forcedErrMtx.Lock()
defer l.forcedErrMtx.Unlock()
l.forcedErr = err
}
func (l *testLoop) getForcedError() error {
l.forcedErrMtx.Lock()
defer l.forcedErrMtx.Unlock()
return l.forcedErr
}
func (l *testLoop) stop() {
l.stopFunc()
}
func (l *testLoop) getCache() *scrapeCache {
return nil
}
func TestScrapePoolStop(t *testing.T) {
sp := &scrapePool{
activeTargets: map[uint64]*Target{},
loops: map[uint64]loop{},
cancel: func() {},
client: http.DefaultClient,
metrics: newTestScrapeMetrics(t),
}
var mtx sync.Mutex
stopped := map[uint64]bool{}
numTargets := 20
// Stopping the scrape pool must call stop() on all scrape loops,
// clean them and the respective targets up. It must wait until each loop's
// stop function returned before returning itself.
for i := 0; i < numTargets; i++ {
t := &Target{
labels: labels.FromStrings(model.AddressLabel, fmt.Sprintf("example.com:%d", i)),
}
l := &testLoop{}
d := time.Duration((i+1)*20) * time.Millisecond
l.stopFunc = func() {
time.Sleep(d)
mtx.Lock()
stopped[t.hash()] = true
mtx.Unlock()
}
sp.activeTargets[t.hash()] = t
sp.loops[t.hash()] = l
}
done := make(chan struct{})
stopTime := time.Now()
go func() {
sp.stop()
close(done)
}()
select {
case <-time.After(5 * time.Second):
require.Fail(t, "scrapeLoop.stop() did not return as expected")
case <-done:
// This should have taken at least as long as the last target slept.
require.GreaterOrEqual(t, time.Since(stopTime), time.Duration(numTargets*20)*time.Millisecond, "scrapeLoop.stop() exited before all targets stopped")
}
mtx.Lock()
require.Len(t, stopped, numTargets, "Unexpected number of stopped loops")
mtx.Unlock()
require.Empty(t, sp.activeTargets, "Targets were not cleared on stopping: %d left", len(sp.activeTargets))
require.Empty(t, sp.loops, "Loops were not cleared on stopping: %d left", len(sp.loops))
}
func TestScrapePoolReload(t *testing.T) {
var mtx sync.Mutex
numTargets := 20
stopped := map[uint64]bool{}
reloadCfg := &config.ScrapeConfig{
ScrapeInterval: model.Duration(3 * time.Second),
ScrapeTimeout: model.Duration(2 * time.Second),
}
// On starting to run, new loops created on reload check whether their preceding
// equivalents have been stopped.
newLoop := func(opts scrapeLoopOptions) loop {
l := &testLoop{interval: time.Duration(reloadCfg.ScrapeInterval), timeout: time.Duration(reloadCfg.ScrapeTimeout)}
l.startFunc = func(interval, timeout time.Duration, errc chan<- error) {
require.Equal(t, 3*time.Second, interval, "Unexpected scrape interval")
require.Equal(t, 2*time.Second, timeout, "Unexpected scrape timeout")
mtx.Lock()
targetScraper := opts.scraper.(*targetScraper)
require.True(t, stopped[targetScraper.hash()], "Scrape loop for %v not stopped yet", targetScraper)
mtx.Unlock()
}
return l
}
sp := &scrapePool{
appendable: &nopAppendable{},
activeTargets: map[uint64]*Target{},
loops: map[uint64]loop{},
newLoop: newLoop,
logger: nil,
client: http.DefaultClient,
metrics: newTestScrapeMetrics(t),
symbolTable: labels.NewSymbolTable(),
}
// Reloading a scrape pool with a new scrape configuration must stop all scrape
// loops and start new ones. A new loop must not be started before the preceding
// one terminated.
for i := 0; i < numTargets; i++ {
labels := labels.FromStrings(model.AddressLabel, fmt.Sprintf("example.com:%d", i))
t := &Target{
labels: labels,
discoveredLabels: labels,
}
l := &testLoop{}
d := time.Duration((i+1)*20) * time.Millisecond
l.stopFunc = func() {
time.Sleep(d)
mtx.Lock()
stopped[t.hash()] = true
mtx.Unlock()
}
sp.activeTargets[t.hash()] = t
sp.loops[t.hash()] = l
}
done := make(chan struct{})
beforeTargets := map[uint64]*Target{}
for h, t := range sp.activeTargets {
beforeTargets[h] = t
}
reloadTime := time.Now()
go func() {
sp.reload(reloadCfg)
close(done)
}()
select {
case <-time.After(5 * time.Second):
require.FailNow(t, "scrapeLoop.reload() did not return as expected")
case <-done:
// This should have taken at least as long as the last target slept.
require.GreaterOrEqual(t, time.Since(reloadTime), time.Duration(numTargets*20)*time.Millisecond, "scrapeLoop.stop() exited before all targets stopped")
}
mtx.Lock()
require.Len(t, stopped, numTargets, "Unexpected number of stopped loops")
mtx.Unlock()
require.Equal(t, sp.activeTargets, beforeTargets, "Reloading affected target states unexpectedly")
require.Len(t, sp.loops, numTargets, "Unexpected number of stopped loops after reload")
}
func TestScrapePoolReloadPreserveRelabeledIntervalTimeout(t *testing.T) {
reloadCfg := &config.ScrapeConfig{
ScrapeInterval: model.Duration(3 * time.Second),
ScrapeTimeout: model.Duration(2 * time.Second),
}
newLoop := func(opts scrapeLoopOptions) loop {
l := &testLoop{interval: opts.interval, timeout: opts.timeout}
l.startFunc = func(interval, timeout time.Duration, errc chan<- error) {
require.Equal(t, 5*time.Second, interval, "Unexpected scrape interval")
require.Equal(t, 3*time.Second, timeout, "Unexpected scrape timeout")
}
return l
}
sp := &scrapePool{
appendable: &nopAppendable{},
activeTargets: map[uint64]*Target{
1: {
labels: labels.FromStrings(model.ScrapeIntervalLabel, "5s", model.ScrapeTimeoutLabel, "3s"),
},
},
loops: map[uint64]loop{
1: noopLoop(),
},
newLoop: newLoop,
logger: nil,
client: http.DefaultClient,
metrics: newTestScrapeMetrics(t),
symbolTable: labels.NewSymbolTable(),
}
err := sp.reload(reloadCfg)
if err != nil {
t.Fatalf("unable to reload configuration: %s", err)
}
}
func TestScrapePoolTargetLimit(t *testing.T) {
var wg sync.WaitGroup
// On starting to run, new loops created on reload check whether their preceding
// equivalents have been stopped.
newLoop := func(opts scrapeLoopOptions) loop {
wg.Add(1)
l := &testLoop{
startFunc: func(interval, timeout time.Duration, errc chan<- error) {
wg.Done()
},
stopFunc: func() {},
}
return l
}
sp := &scrapePool{
appendable: &nopAppendable{},
activeTargets: map[uint64]*Target{},
loops: map[uint64]loop{},
newLoop: newLoop,
logger: log.NewNopLogger(),
client: http.DefaultClient,
metrics: newTestScrapeMetrics(t),
symbolTable: labels.NewSymbolTable(),
}
tgs := []*targetgroup.Group{}
for i := 0; i < 50; i++ {
tgs = append(tgs,
&targetgroup.Group{
Targets: []model.LabelSet{
{model.AddressLabel: model.LabelValue(fmt.Sprintf("127.0.0.1:%d", 9090+i))},
},
},
)
}
var limit uint
reloadWithLimit := func(l uint) {
limit = l
require.NoError(t, sp.reload(&config.ScrapeConfig{
ScrapeInterval: model.Duration(3 * time.Second),
ScrapeTimeout: model.Duration(2 * time.Second),
TargetLimit: l,
}))
}
var targets int
loadTargets := func(n int) {
targets = n
sp.Sync(tgs[:n])
}
validateIsRunning := func() {
wg.Wait()
for _, l := range sp.loops {
require.True(t, l.(*testLoop).runOnce, "loop should be running")
}
}
validateErrorMessage := func(shouldErr bool) {
for _, l := range sp.loops {
lerr := l.(*testLoop).getForcedError()
if shouldErr {
require.Error(t, lerr, "error was expected for %d targets with a limit of %d", targets, limit)
require.Equal(t, fmt.Sprintf("target_limit exceeded (number of targets: %d, limit: %d)", targets, limit), lerr.Error())
} else {
require.NoError(t, lerr)
}
}
}
reloadWithLimit(0)
loadTargets(50)
validateIsRunning()
// Simulate an initial config with a limit.
sp.config.TargetLimit = 30
limit = 30
loadTargets(50)
validateIsRunning()
validateErrorMessage(true)
reloadWithLimit(50)
validateIsRunning()
validateErrorMessage(false)
reloadWithLimit(40)
validateIsRunning()
validateErrorMessage(true)
loadTargets(30)
validateIsRunning()
validateErrorMessage(false)
loadTargets(40)
validateIsRunning()
validateErrorMessage(false)
loadTargets(41)
validateIsRunning()
validateErrorMessage(true)
reloadWithLimit(0)
validateIsRunning()
validateErrorMessage(false)
reloadWithLimit(51)
validateIsRunning()
validateErrorMessage(false)
tgs = append(tgs,
&targetgroup.Group{
Targets: []model.LabelSet{
{model.AddressLabel: model.LabelValue("127.0.0.1:1090")},
},
},
&targetgroup.Group{
Targets: []model.LabelSet{
{model.AddressLabel: model.LabelValue("127.0.0.1:1090")},
},
},
)
sp.Sync(tgs)
validateIsRunning()
validateErrorMessage(false)
}
func TestScrapePoolAppender(t *testing.T) {
cfg := &config.ScrapeConfig{}
app := &nopAppendable{}
sp, _ := newScrapePool(cfg, app, 0, nil, nil, &Options{}, newTestScrapeMetrics(t))
loop := sp.newLoop(scrapeLoopOptions{
target: &Target{},
})
appl, ok := loop.(*scrapeLoop)
require.True(t, ok, "Expected scrapeLoop but got %T", loop)
wrapped := appender(appl.appender(context.Background()), 0, 0, histogram.ExponentialSchemaMax)
tl, ok := wrapped.(*timeLimitAppender)
require.True(t, ok, "Expected timeLimitAppender but got %T", wrapped)
_, ok = tl.Appender.(nopAppender)
require.True(t, ok, "Expected base appender but got %T", tl.Appender)
sampleLimit := 100
loop = sp.newLoop(scrapeLoopOptions{
target: &Target{},
sampleLimit: sampleLimit,
})
appl, ok = loop.(*scrapeLoop)
require.True(t, ok, "Expected scrapeLoop but got %T", loop)
wrapped = appender(appl.appender(context.Background()), sampleLimit, 0, histogram.ExponentialSchemaMax)
sl, ok := wrapped.(*limitAppender)
require.True(t, ok, "Expected limitAppender but got %T", wrapped)
tl, ok = sl.Appender.(*timeLimitAppender)
require.True(t, ok, "Expected timeLimitAppender but got %T", sl.Appender)
_, ok = tl.Appender.(nopAppender)
require.True(t, ok, "Expected base appender but got %T", tl.Appender)
wrapped = appender(appl.appender(context.Background()), sampleLimit, 100, histogram.ExponentialSchemaMax)
bl, ok := wrapped.(*bucketLimitAppender)
require.True(t, ok, "Expected bucketLimitAppender but got %T", wrapped)
sl, ok = bl.Appender.(*limitAppender)
require.True(t, ok, "Expected limitAppender but got %T", bl)
tl, ok = sl.Appender.(*timeLimitAppender)
require.True(t, ok, "Expected timeLimitAppender but got %T", sl.Appender)
_, ok = tl.Appender.(nopAppender)
require.True(t, ok, "Expected base appender but got %T", tl.Appender)
wrapped = appender(appl.appender(context.Background()), sampleLimit, 100, 0)
ml, ok := wrapped.(*maxSchemaAppender)
require.True(t, ok, "Expected maxSchemaAppender but got %T", wrapped)
bl, ok = ml.Appender.(*bucketLimitAppender)
require.True(t, ok, "Expected bucketLimitAppender but got %T", wrapped)
sl, ok = bl.Appender.(*limitAppender)
require.True(t, ok, "Expected limitAppender but got %T", bl)
tl, ok = sl.Appender.(*timeLimitAppender)
require.True(t, ok, "Expected timeLimitAppender but got %T", sl.Appender)
_, ok = tl.Appender.(nopAppender)
require.True(t, ok, "Expected base appender but got %T", tl.Appender)
}
func TestScrapePoolRaces(t *testing.T) {
interval, _ := model.ParseDuration("1s")
timeout, _ := model.ParseDuration("500ms")
newConfig := func() *config.ScrapeConfig {
return &config.ScrapeConfig{ScrapeInterval: interval, ScrapeTimeout: timeout}
}
sp, _ := newScrapePool(newConfig(), &nopAppendable{}, 0, nil, nil, &Options{}, newTestScrapeMetrics(t))
tgts := []*targetgroup.Group{
{
Targets: []model.LabelSet{
{model.AddressLabel: "127.0.0.1:9090"},
{model.AddressLabel: "127.0.0.2:9090"},
{model.AddressLabel: "127.0.0.3:9090"},
{model.AddressLabel: "127.0.0.4:9090"},
{model.AddressLabel: "127.0.0.5:9090"},
{model.AddressLabel: "127.0.0.6:9090"},
{model.AddressLabel: "127.0.0.7:9090"},
{model.AddressLabel: "127.0.0.8:9090"},
},
},
}
sp.Sync(tgts)
active := sp.ActiveTargets()
dropped := sp.DroppedTargets()
expectedActive, expectedDropped := len(tgts[0].Targets), 0
require.Len(t, active, expectedActive, "Invalid number of active targets")
require.Len(t, dropped, expectedDropped, "Invalid number of dropped targets")
for i := 0; i < 20; i++ {
time.Sleep(10 * time.Millisecond)
sp.reload(newConfig())
}
sp.stop()
}
func TestScrapePoolScrapeLoopsStarted(t *testing.T) {
var wg sync.WaitGroup
newLoop := func(opts scrapeLoopOptions) loop {
wg.Add(1)
l := &testLoop{
startFunc: func(interval, timeout time.Duration, errc chan<- error) {
wg.Done()
},
stopFunc: func() {},
}
return l
}
sp := &scrapePool{
appendable: &nopAppendable{},
activeTargets: map[uint64]*Target{},
loops: map[uint64]loop{},
newLoop: newLoop,
logger: nil,
client: http.DefaultClient,
metrics: newTestScrapeMetrics(t),
symbolTable: labels.NewSymbolTable(),
}
tgs := []*targetgroup.Group{
{
Targets: []model.LabelSet{
{model.AddressLabel: model.LabelValue("127.0.0.1:9090")},
},
},
{
Targets: []model.LabelSet{
{model.AddressLabel: model.LabelValue("127.0.0.1:9090")},
},
},
}
require.NoError(t, sp.reload(&config.ScrapeConfig{
ScrapeInterval: model.Duration(3 * time.Second),
ScrapeTimeout: model.Duration(2 * time.Second),
}))
sp.Sync(tgs)
require.Len(t, sp.loops, 1)
wg.Wait()
for _, l := range sp.loops {
require.True(t, l.(*testLoop).runOnce, "loop should be running")
}
}
func newBasicScrapeLoop(t testing.TB, ctx context.Context, scraper scraper, app func(ctx context.Context) storage.Appender, interval time.Duration) *scrapeLoop {
return newScrapeLoop(ctx,
scraper,
nil, nil,
nopMutator,
nopMutator,
app,
nil,
labels.NewSymbolTable(),
0,
true,
false,
true,
0, 0, histogram.ExponentialSchemaMax,
nil,
interval,
time.Hour,
false,
false,
false,
false,
false,
nil,
false,
newTestScrapeMetrics(t),
false,
model.LegacyValidation,
)
}
func TestScrapeLoopStopBeforeRun(t *testing.T) {
scraper := &testScraper{}
sl := newBasicScrapeLoop(t, context.Background(), scraper, nil, 1)
// The scrape pool synchronizes on stopping scrape loops. However, new scrape
// loops are started asynchronously. Thus it's possible, that a loop is stopped
// again before having started properly.
// Stopping not-yet-started loops must block until the run method was called and exited.
// The run method must exit immediately.
stopDone := make(chan struct{})
go func() {
sl.stop()
close(stopDone)
}()
select {
case <-stopDone:
require.FailNow(t, "Stopping terminated before run exited successfully.")
case <-time.After(500 * time.Millisecond):
}
// Running the scrape loop must exit before calling the scraper even once.
scraper.scrapeFunc = func(context.Context, io.Writer) error {
require.FailNow(t, "Scraper was called for terminated scrape loop.")
return nil
}
runDone := make(chan struct{})
go func() {
sl.run(nil)
close(runDone)
}()
select {
case <-runDone:
case <-time.After(1 * time.Second):
require.FailNow(t, "Running terminated scrape loop did not exit.")
}
select {
case <-stopDone:
case <-time.After(1 * time.Second):
require.FailNow(t, "Stopping did not terminate after running exited.")
}
}
func nopMutator(l labels.Labels) labels.Labels { return l }
func TestScrapeLoopStop(t *testing.T) {
var (
signal = make(chan struct{}, 1)
appender = &collectResultAppender{}
scraper = &testScraper{}
app = func(ctx context.Context) storage.Appender { return appender }
)
sl := newBasicScrapeLoop(t, context.Background(), scraper, app, 10*time.Millisecond)
// Terminate loop after 2 scrapes.
numScrapes := 0
scraper.scrapeFunc = func(ctx context.Context, w io.Writer) error {
numScrapes++
if numScrapes == 2 {
go sl.stop()
<-sl.ctx.Done()
}
w.Write([]byte("metric_a 42\n"))
return ctx.Err()
}
go func() {
sl.run(nil)
signal <- struct{}{}
}()
select {
case <-signal:
case <-time.After(5 * time.Second):
require.FailNow(t, "Scrape wasn't stopped.")
}
// We expected 1 actual sample for each scrape plus 5 for report samples.
// At least 2 scrapes were made, plus the final stale markers.
require.GreaterOrEqual(t, len(appender.resultFloats), 6*3, "Expected at least 3 scrapes with 6 samples each.")
require.Zero(t, len(appender.resultFloats)%6, "There is a scrape with missing samples.")
// All samples in a scrape must have the same timestamp.
var ts int64
for i, s := range appender.resultFloats {
switch {
case i%6 == 0:
ts = s.t
case s.t != ts:
t.Fatalf("Unexpected multiple timestamps within single scrape")
}
}
// All samples from the last scrape must be stale markers.
for _, s := range appender.resultFloats[len(appender.resultFloats)-5:] {
require.True(t, value.IsStaleNaN(s.f), "Appended last sample not as expected. Wanted: stale NaN Got: %x", math.Float64bits(s.f))
}
}
func TestScrapeLoopRun(t *testing.T) {
var (
signal = make(chan struct{}, 1)
errc = make(chan error)
scraper = &testScraper{}
app = func(ctx context.Context) storage.Appender { return &nopAppender{} }
scrapeMetrics = newTestScrapeMetrics(t)
)
ctx, cancel := context.WithCancel(context.Background())
sl := newScrapeLoop(ctx,
scraper,
nil, nil,
nopMutator,
nopMutator,
app,
nil,
nil,
0,
true,
false,
true,
0, 0, histogram.ExponentialSchemaMax,
nil,
time.Second,
time.Hour,
false,
false,
false,
false,
false,
nil,
false,
scrapeMetrics,
false,
model.LegacyValidation,
)
// The loop must terminate during the initial offset if the context
// is canceled.
scraper.offsetDur = time.Hour
go func() {
sl.run(errc)
signal <- struct{}{}
}()
// Wait to make sure we are actually waiting on the offset.
time.Sleep(1 * time.Second)
cancel()
select {
case <-signal:
case <-time.After(5 * time.Second):
require.FailNow(t, "Cancellation during initial offset failed.")
case err := <-errc:
require.FailNow(t, "Unexpected error: %s", err)
}
// The provided timeout must cause cancellation of the context passed down to the
// scraper. The scraper has to respect the context.
scraper.offsetDur = 0
block := make(chan struct{})
scraper.scrapeFunc = func(ctx context.Context, _ io.Writer) error {
select {
case <-block:
case <-ctx.Done():
return ctx.Err()
}
return nil
}
ctx, cancel = context.WithCancel(context.Background())
sl = newBasicScrapeLoop(t, ctx, scraper, app, time.Second)
sl.timeout = 100 * time.Millisecond
go func() {
sl.run(errc)
signal <- struct{}{}
}()
select {
case err := <-errc:
require.ErrorIs(t, err, context.DeadlineExceeded)
case <-time.After(3 * time.Second):
require.FailNow(t, "Expected timeout error but got none.")
}
// We already caught the timeout error and are certainly in the loop.
// Let the scrapes returns immediately to cause no further timeout errors
// and check whether canceling the parent context terminates the loop.
close(block)
cancel()
select {
case <-signal:
// Loop terminated as expected.
case err := <-errc:
require.FailNow(t, "Unexpected error: %s", err)
case <-time.After(3 * time.Second):
require.FailNow(t, "Loop did not terminate on context cancellation")
}
}
func TestScrapeLoopForcedErr(t *testing.T) {
var (
signal = make(chan struct{}, 1)
errc = make(chan error)
scraper = &testScraper{}
app = func(ctx context.Context) storage.Appender { return &nopAppender{} }
)
ctx, cancel := context.WithCancel(context.Background())
sl := newBasicScrapeLoop(t, ctx, scraper, app, time.Second)
forcedErr := fmt.Errorf("forced err")
sl.setForcedError(forcedErr)
scraper.scrapeFunc = func(context.Context, io.Writer) error {
require.FailNow(t, "Should not be scraped.")
return nil
}
go func() {
sl.run(errc)
signal <- struct{}{}
}()
select {
case err := <-errc:
require.ErrorIs(t, err, forcedErr)
case <-time.After(3 * time.Second):
require.FailNow(t, "Expected forced error but got none.")
}
cancel()
select {
case <-signal:
case <-time.After(5 * time.Second):
require.FailNow(t, "Scrape not stopped.")
}
}
func TestScrapeLoopMetadata(t *testing.T) {
var (
signal = make(chan struct{})
scraper = &testScraper{}
scrapeMetrics = newTestScrapeMetrics(t)
cache = newScrapeCache(scrapeMetrics)
)
defer close(signal)
ctx, cancel := context.WithCancel(context.Background())
sl := newScrapeLoop(ctx,
scraper,
nil, nil,
nopMutator,
nopMutator,
func(ctx context.Context) storage.Appender { return nopAppender{} },
cache,
labels.NewSymbolTable(),
0,
true,
false,
true,
0, 0, histogram.ExponentialSchemaMax,
nil,
0,
0,
false,
false,
false,
false,
false,
nil,
false,
scrapeMetrics,
false,
model.LegacyValidation,
)
defer cancel()
slApp := sl.appender(ctx)
total, _, _, err := sl.append(slApp, []byte(`# TYPE test_metric counter
# HELP test_metric some help text
# UNIT test_metric metric
test_metric 1
# TYPE test_metric_no_help gauge
# HELP test_metric_no_type other help text
# EOF`), "application/openmetrics-text", time.Now())
require.NoError(t, err)
require.NoError(t, slApp.Commit())
require.Equal(t, 1, total)
md, ok := cache.GetMetadata("test_metric")
require.True(t, ok, "expected metadata to be present")
require.Equal(t, model.MetricTypeCounter, md.Type, "unexpected metric type")
require.Equal(t, "some help text", md.Help)
require.Equal(t, "metric", md.Unit)
md, ok = cache.GetMetadata("test_metric_no_help")
require.True(t, ok, "expected metadata to be present")
require.Equal(t, model.MetricTypeGauge, md.Type, "unexpected metric type")
require.Equal(t, "", md.Help)
require.Equal(t, "", md.Unit)
md, ok = cache.GetMetadata("test_metric_no_type")
require.True(t, ok, "expected metadata to be present")
require.Equal(t, model.MetricTypeUnknown, md.Type, "unexpected metric type")
require.Equal(t, "other help text", md.Help)
require.Equal(t, "", md.Unit)
}
func simpleTestScrapeLoop(t testing.TB) (context.Context, *scrapeLoop) {
// Need a full storage for correct Add/AddFast semantics.
s := teststorage.New(t)
t.Cleanup(func() { s.Close() })
ctx, cancel := context.WithCancel(context.Background())
sl := newBasicScrapeLoop(t, ctx, &testScraper{}, s.Appender, 0)
t.Cleanup(func() { cancel() })
return ctx, sl
}
func TestScrapeLoopSeriesAdded(t *testing.T) {
ctx, sl := simpleTestScrapeLoop(t)
slApp := sl.appender(ctx)
total, added, seriesAdded, err := sl.append(slApp, []byte("test_metric 1\n"), "", time.Time{})
require.NoError(t, err)
require.NoError(t, slApp.Commit())
require.Equal(t, 1, total)
require.Equal(t, 1, added)
require.Equal(t, 1, seriesAdded)
slApp = sl.appender(ctx)
total, added, seriesAdded, err = sl.append(slApp, []byte("test_metric 1\n"), "", time.Time{})
require.NoError(t, slApp.Commit())
require.NoError(t, err)
require.Equal(t, 1, total)
require.Equal(t, 1, added)
require.Equal(t, 0, seriesAdded)
}
func TestScrapeLoopFailWithInvalidLabelsAfterRelabel(t *testing.T) {
s := teststorage.New(t)
defer s.Close()
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
target := &Target{
labels: labels.FromStrings("pod_label_invalid_012", "test"),
}
relabelConfig := []*relabel.Config{{
Action: relabel.LabelMap,
Regex: relabel.MustNewRegexp("pod_label_invalid_(.+)"),
Separator: ";",
Replacement: "$1",
}}
sl := newBasicScrapeLoop(t, ctx, &testScraper{}, s.Appender, 0)
sl.sampleMutator = func(l labels.Labels) labels.Labels {
return mutateSampleLabels(l, target, true, relabelConfig)
}
slApp := sl.appender(ctx)
total, added, seriesAdded, err := sl.append(slApp, []byte("test_metric 1\n"), "", time.Time{})
require.ErrorContains(t, err, "invalid metric name or label names")
require.NoError(t, slApp.Rollback())
require.Equal(t, 1, total)
require.Equal(t, 0, added)
require.Equal(t, 0, seriesAdded)
}
func TestScrapeLoopFailLegacyUnderUTF8(t *testing.T) {
// Test that scrapes fail when default validation is utf8 but scrape config is
// legacy.
model.NameValidationScheme = model.UTF8Validation
defer func() {
model.NameValidationScheme = model.LegacyValidation
}()
s := teststorage.New(t)
defer s.Close()
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
sl := newBasicScrapeLoop(t, ctx, &testScraper{}, s.Appender, 0)
sl.validationScheme = model.LegacyValidation
slApp := sl.appender(ctx)
total, added, seriesAdded, err := sl.append(slApp, []byte("{\"test.metric\"} 1\n"), "", time.Time{})
require.ErrorContains(t, err, "invalid metric name or label names")
require.NoError(t, slApp.Rollback())
require.Equal(t, 1, total)
require.Equal(t, 0, added)
require.Equal(t, 0, seriesAdded)
// When scrapeloop has validation set to UTF-8, the metric is allowed.
sl.validationScheme = model.UTF8Validation
slApp = sl.appender(ctx)
total, added, seriesAdded, err = sl.append(slApp, []byte("{\"test.metric\"} 1\n"), "", time.Time{})
require.NoError(t, err)
require.Equal(t, 1, total)
require.Equal(t, 1, added)
require.Equal(t, 1, seriesAdded)
}
func makeTestMetrics(n int) []byte {
// Construct a metrics string to parse
sb := bytes.Buffer{}
for i := 0; i < n; i++ {
fmt.Fprintf(&sb, "# TYPE metric_a gauge\n")
fmt.Fprintf(&sb, "# HELP metric_a help text\n")
fmt.Fprintf(&sb, "metric_a{foo=\"%d\",bar=\"%d\"} 1\n", i, i*100)
}
fmt.Fprintf(&sb, "# EOF\n")
return sb.Bytes()
}
func BenchmarkScrapeLoopAppend(b *testing.B) {
ctx, sl := simpleTestScrapeLoop(b)
slApp := sl.appender(ctx)
metrics := makeTestMetrics(100)
ts := time.Time{}
b.ResetTimer()
for i := 0; i < b.N; i++ {
ts = ts.Add(time.Second)
_, _, _, _ = sl.append(slApp, metrics, "", ts)
}
}
func BenchmarkScrapeLoopAppendOM(b *testing.B) {
ctx, sl := simpleTestScrapeLoop(b)
slApp := sl.appender(ctx)
metrics := makeTestMetrics(100)
ts := time.Time{}
b.ResetTimer()
for i := 0; i < b.N; i++ {
ts = ts.Add(time.Second)
_, _, _, _ = sl.append(slApp, metrics, "application/openmetrics-text", ts)
}
}
func TestScrapeLoopRunCreatesStaleMarkersOnFailedScrape(t *testing.T) {
appender := &collectResultAppender{}
var (
signal = make(chan struct{}, 1)
scraper = &testScraper{}
app = func(ctx context.Context) storage.Appender { return appender }
)
ctx, cancel := context.WithCancel(context.Background())
sl := newBasicScrapeLoop(t, ctx, scraper, app, 10*time.Millisecond)
// Succeed once, several failures, then stop.
numScrapes := 0
scraper.scrapeFunc = func(ctx context.Context, w io.Writer) error {
numScrapes++
switch numScrapes {
case 1:
w.Write([]byte("metric_a 42\n"))
return nil
case 5:
cancel()
}
return errors.New("scrape failed")
}
go func() {
sl.run(nil)
signal <- struct{}{}
}()
select {
case <-signal:
case <-time.After(5 * time.Second):
require.FailNow(t, "Scrape wasn't stopped.")
}
// 1 successfully scraped sample, 1 stale marker after first fail, 5 report samples for
// each scrape successful or not.
require.Len(t, appender.resultFloats, 27, "Appended samples not as expected:\n%s", appender)
require.Equal(t, 42.0, appender.resultFloats[0].f, "Appended first sample not as expected")
require.True(t, value.IsStaleNaN(appender.resultFloats[6].f),
"Appended second sample not as expected. Wanted: stale NaN Got: %x", math.Float64bits(appender.resultFloats[6].f))
}
func TestScrapeLoopRunCreatesStaleMarkersOnParseFailure(t *testing.T) {
appender := &collectResultAppender{}
var (
signal = make(chan struct{}, 1)
scraper = &testScraper{}
app = func(ctx context.Context) storage.Appender { return appender }
numScrapes = 0
)
ctx, cancel := context.WithCancel(context.Background())
sl := newBasicScrapeLoop(t, ctx, scraper, app, 10*time.Millisecond)
// Succeed once, several failures, then stop.
scraper.scrapeFunc = func(ctx context.Context, w io.Writer) error {
numScrapes++
switch numScrapes {
case 1:
w.Write([]byte("metric_a 42\n"))
return nil
case 2:
w.Write([]byte("7&-\n"))
return nil
case 3:
cancel()
}
return errors.New("scrape failed")
}
go func() {
sl.run(nil)
signal <- struct{}{}
}()
select {
case <-signal:
case <-time.After(5 * time.Second):
require.FailNow(t, "Scrape wasn't stopped.")
}
// 1 successfully scraped sample, 1 stale marker after first fail, 5 report samples for
// each scrape successful or not.
require.Len(t, appender.resultFloats, 17, "Appended samples not as expected:\n%s", appender)
require.Equal(t, 42.0, appender.resultFloats[0].f, "Appended first sample not as expected")
require.True(t, value.IsStaleNaN(appender.resultFloats[6].f),
"Appended second sample not as expected. Wanted: stale NaN Got: %x", math.Float64bits(appender.resultFloats[6].f))
}
func TestScrapeLoopCache(t *testing.T) {
s := teststorage.New(t)
defer s.Close()
appender := &collectResultAppender{}
var (
signal = make(chan struct{}, 1)
scraper = &testScraper{}
app = func(ctx context.Context) storage.Appender { appender.next = s.Appender(ctx); return appender }
)
ctx, cancel := context.WithCancel(context.Background())
// Decreasing the scrape interval could make the test fail, as multiple scrapes might be initiated at identical millisecond timestamps.
// See https://github.com/prometheus/prometheus/issues/12727.
sl := newBasicScrapeLoop(t, ctx, scraper, app, 100*time.Millisecond)
numScrapes := 0
scraper.scrapeFunc = func(ctx context.Context, w io.Writer) error {
switch numScrapes {
case 1, 2:
_, ok := sl.cache.series["metric_a"]
require.True(t, ok, "metric_a missing from cache after scrape %d", numScrapes)
_, ok = sl.cache.series["metric_b"]
require.True(t, ok, "metric_b missing from cache after scrape %d", numScrapes)
case 3:
_, ok := sl.cache.series["metric_a"]
require.True(t, ok, "metric_a missing from cache after scrape %d", numScrapes)
_, ok = sl.cache.series["metric_b"]
require.False(t, ok, "metric_b present in cache after scrape %d", numScrapes)
}
numScrapes++
switch numScrapes {
case 1:
w.Write([]byte("metric_a 42\nmetric_b 43\n"))
return nil
case 3:
w.Write([]byte("metric_a 44\n"))
return nil
case 4:
cancel()
}
return fmt.Errorf("scrape failed")
}
go func() {
sl.run(nil)
signal <- struct{}{}
}()
select {
case <-signal:
case <-time.After(5 * time.Second):
require.FailNow(t, "Scrape wasn't stopped.")
}
// 1 successfully scraped sample, 1 stale marker after first fail, 5 report samples for
// each scrape successful or not.
require.Len(t, appender.resultFloats, 26, "Appended samples not as expected:\n%s", appender)
}
func TestScrapeLoopCacheMemoryExhaustionProtection(t *testing.T) {
s := teststorage.New(t)
defer s.Close()
sapp := s.Appender(context.Background())
appender := &collectResultAppender{next: sapp}
var (
signal = make(chan struct{}, 1)
scraper = &testScraper{}
app = func(ctx context.Context) storage.Appender { return appender }
)
ctx, cancel := context.WithCancel(context.Background())
sl := newBasicScrapeLoop(t, ctx, scraper, app, 10*time.Millisecond)
numScrapes := 0
scraper.scrapeFunc = func(ctx context.Context, w io.Writer) error {
numScrapes++
if numScrapes < 5 {
s := ""
for i := 0; i < 500; i++ {
s = fmt.Sprintf("%smetric_%d_%d 42\n", s, i, numScrapes)
}
w.Write([]byte(s + "&"))
} else {
cancel()
}
return nil
}
go func() {
sl.run(nil)
signal <- struct{}{}
}()
select {
case <-signal:
case <-time.After(5 * time.Second):
require.FailNow(t, "Scrape wasn't stopped.")
}
require.LessOrEqual(t, len(sl.cache.series), 2000, "More than 2000 series cached.")
}
func TestScrapeLoopAppend(t *testing.T) {
tests := []struct {
title string
honorLabels bool
scrapeLabels string
discoveryLabels []string
expLset labels.Labels
expValue float64
}{
{
// When "honor_labels" is not set
// label name collision is handler by adding a prefix.
title: "Label name collision",
honorLabels: false,
scrapeLabels: `metric{n="1"} 0`,
discoveryLabels: []string{"n", "2"},
expLset: labels.FromStrings("__name__", "metric", "exported_n", "1", "n", "2"),
expValue: 0,
}, {
// When "honor_labels" is not set
// exported label from discovery don't get overwritten
title: "Label name collision",
honorLabels: false,
scrapeLabels: `metric 0`,
discoveryLabels: []string{"n", "2", "exported_n", "2"},
expLset: labels.FromStrings("__name__", "metric", "n", "2", "exported_n", "2"),
expValue: 0,
}, {
// Labels with no value need to be removed as these should not be ingested.
title: "Delete Empty labels",
honorLabels: false,
scrapeLabels: `metric{n=""} 0`,
discoveryLabels: nil,
expLset: labels.FromStrings("__name__", "metric"),
expValue: 0,
}, {
// Honor Labels should ignore labels with the same name.
title: "Honor Labels",
honorLabels: true,
scrapeLabels: `metric{n1="1", n2="2"} 0`,
discoveryLabels: []string{"n1", "0"},
expLset: labels.FromStrings("__name__", "metric", "n1", "1", "n2", "2"),
expValue: 0,
}, {
title: "Stale - NaN",
honorLabels: false,
scrapeLabels: `metric NaN`,
discoveryLabels: nil,
expLset: labels.FromStrings("__name__", "metric"),
expValue: math.Float64frombits(value.NormalNaN),
},
}
for _, test := range tests {
app := &collectResultAppender{}
discoveryLabels := &Target{
labels: labels.FromStrings(test.discoveryLabels...),
}
sl := newBasicScrapeLoop(t, context.Background(), nil, func(ctx context.Context) storage.Appender { return app }, 0)
sl.sampleMutator = func(l labels.Labels) labels.Labels {
return mutateSampleLabels(l, discoveryLabels, test.honorLabels, nil)
}
sl.reportSampleMutator = func(l labels.Labels) labels.Labels {
return mutateReportSampleLabels(l, discoveryLabels)
}
now := time.Now()
slApp := sl.appender(context.Background())
_, _, _, err := sl.append(slApp, []byte(test.scrapeLabels), "", now)
require.NoError(t, err)
require.NoError(t, slApp.Commit())
expected := []floatSample{
{
metric: test.expLset,
t: timestamp.FromTime(now),
f: test.expValue,
},
}
t.Logf("Test:%s", test.title)
requireEqual(t, expected, app.resultFloats)
}
}
func requireEqual(t *testing.T, expected, actual interface{}, msgAndArgs ...interface{}) {
testutil.RequireEqualWithOptions(t, expected, actual,
[]cmp.Option{cmp.Comparer(equalFloatSamples), cmp.AllowUnexported(histogramSample{})},
msgAndArgs...)
}
func TestScrapeLoopAppendForConflictingPrefixedLabels(t *testing.T) {
testcases := map[string]struct {
targetLabels []string
exposedLabels string
expected []string
}{
"One target label collides with existing label": {
targetLabels: []string{"foo", "2"},
exposedLabels: `metric{foo="1"} 0`,
expected: []string{"__name__", "metric", "exported_foo", "1", "foo", "2"},
},
"One target label collides with existing label, plus target label already with prefix 'exported'": {
targetLabels: []string{"foo", "2", "exported_foo", "3"},
exposedLabels: `metric{foo="1"} 0`,
expected: []string{"__name__", "metric", "exported_exported_foo", "1", "exported_foo", "3", "foo", "2"},
},
"One target label collides with existing label, plus existing label already with prefix 'exported": {
targetLabels: []string{"foo", "3"},
exposedLabels: `metric{foo="1", exported_foo="2"} 0`,
expected: []string{"__name__", "metric", "exported_exported_foo", "1", "exported_foo", "2", "foo", "3"},
},
"One target label collides with existing label, both already with prefix 'exported'": {
targetLabels: []string{"exported_foo", "2"},
exposedLabels: `metric{exported_foo="1"} 0`,
expected: []string{"__name__", "metric", "exported_exported_foo", "1", "exported_foo", "2"},
},
"Two target labels collide with existing labels, both with and without prefix 'exported'": {
targetLabels: []string{"foo", "3", "exported_foo", "4"},
exposedLabels: `metric{foo="1", exported_foo="2"} 0`,
expected: []string{
"__name__", "metric", "exported_exported_foo", "1", "exported_exported_exported_foo",
"2", "exported_foo", "4", "foo", "3",
},
},
"Extreme example": {
targetLabels: []string{"foo", "0", "exported_exported_foo", "1", "exported_exported_exported_foo", "2"},
exposedLabels: `metric{foo="3", exported_foo="4", exported_exported_exported_foo="5"} 0`,
expected: []string{
"__name__", "metric",
"exported_exported_exported_exported_exported_foo", "5",
"exported_exported_exported_exported_foo", "3",
"exported_exported_exported_foo", "2",
"exported_exported_foo", "1",
"exported_foo", "4",
"foo", "0",
},
},
}
for name, tc := range testcases {
t.Run(name, func(t *testing.T) {
app := &collectResultAppender{}
sl := newBasicScrapeLoop(t, context.Background(), nil, func(ctx context.Context) storage.Appender { return app }, 0)
sl.sampleMutator = func(l labels.Labels) labels.Labels {
return mutateSampleLabels(l, &Target{labels: labels.FromStrings(tc.targetLabels...)}, false, nil)
}
slApp := sl.appender(context.Background())
_, _, _, err := sl.append(slApp, []byte(tc.exposedLabels), "", time.Date(2000, 1, 1, 1, 0, 0, 0, time.UTC))
require.NoError(t, err)
require.NoError(t, slApp.Commit())
requireEqual(t, []floatSample{
{
metric: labels.FromStrings(tc.expected...),
t: timestamp.FromTime(time.Date(2000, 1, 1, 1, 0, 0, 0, time.UTC)),
f: 0,
},
}, app.resultFloats)
})
}
}
func TestScrapeLoopAppendCacheEntryButErrNotFound(t *testing.T) {
// collectResultAppender's AddFast always returns ErrNotFound if we don't give it a next.
app := &collectResultAppender{}
sl := newBasicScrapeLoop(t, context.Background(), nil, func(ctx context.Context) storage.Appender { return app }, 0)
fakeRef := storage.SeriesRef(1)
expValue := float64(1)
metric := []byte(`metric{n="1"} 1`)
p, warning := textparse.New(metric, "", false, labels.NewSymbolTable())
require.NoError(t, warning)
var lset labels.Labels
p.Next()
p.Metric(&lset)
hash := lset.Hash()
// Create a fake entry in the cache
sl.cache.addRef(metric, fakeRef, lset, hash)
now := time.Now()
slApp := sl.appender(context.Background())
_, _, _, err := sl.append(slApp, metric, "", now)
require.NoError(t, err)
require.NoError(t, slApp.Commit())
expected := []floatSample{
{
metric: lset,
t: timestamp.FromTime(now),
f: expValue,
},
}
require.Equal(t, expected, app.resultFloats)
}
func TestScrapeLoopAppendSampleLimit(t *testing.T) {
resApp := &collectResultAppender{}
app := &limitAppender{Appender: resApp, limit: 1}
sl := newBasicScrapeLoop(t, context.Background(), nil, func(ctx context.Context) storage.Appender { return app }, 0)
sl.sampleMutator = func(l labels.Labels) labels.Labels {
if l.Has("deleteme") {
return labels.EmptyLabels()
}
return l
}
sl.sampleLimit = app.limit
// Get the value of the Counter before performing the append.
beforeMetric := dto.Metric{}
err := sl.metrics.targetScrapeSampleLimit.Write(&beforeMetric)
require.NoError(t, err)
beforeMetricValue := beforeMetric.GetCounter().GetValue()
now := time.Now()
slApp := sl.appender(context.Background())
total, added, seriesAdded, err := sl.append(app, []byte("metric_a 1\nmetric_b 1\nmetric_c 1\n"), "", now)
require.ErrorIs(t, err, errSampleLimit)
require.NoError(t, slApp.Rollback())
require.Equal(t, 3, total)
require.Equal(t, 3, added)
require.Equal(t, 1, seriesAdded)
// Check that the Counter has been incremented a single time for the scrape,
// not multiple times for each sample.
metric := dto.Metric{}
err = sl.metrics.targetScrapeSampleLimit.Write(&metric)
require.NoError(t, err)
value := metric.GetCounter().GetValue()
change := value - beforeMetricValue
require.Equal(t, 1.0, change, "Unexpected change of sample limit metric: %f", change)
// And verify that we got the samples that fit under the limit.
want := []floatSample{
{
metric: labels.FromStrings(model.MetricNameLabel, "metric_a"),
t: timestamp.FromTime(now),
f: 1,
},
}
requireEqual(t, want, resApp.rolledbackFloats, "Appended samples not as expected:\n%s", appender)
now = time.Now()
slApp = sl.appender(context.Background())
total, added, seriesAdded, err = sl.append(slApp, []byte("metric_a 1\nmetric_b 1\nmetric_c{deleteme=\"yes\"} 1\nmetric_d 1\nmetric_e 1\nmetric_f 1\nmetric_g 1\nmetric_h{deleteme=\"yes\"} 1\nmetric_i{deleteme=\"yes\"} 1\n"), "", now)
require.ErrorIs(t, err, errSampleLimit)
require.NoError(t, slApp.Rollback())
require.Equal(t, 9, total)
require.Equal(t, 6, added)
require.Equal(t, 0, seriesAdded)
}
func TestScrapeLoop_HistogramBucketLimit(t *testing.T) {
resApp := &collectResultAppender{}
app := &bucketLimitAppender{Appender: resApp, limit: 2}
sl := newBasicScrapeLoop(t, context.Background(), nil, func(ctx context.Context) storage.Appender { return app }, 0)
sl.enableNativeHistogramIngestion = true
sl.sampleMutator = func(l labels.Labels) labels.Labels {
if l.Has("deleteme") {
return labels.EmptyLabels()
}
return l
}
sl.sampleLimit = app.limit
metric := dto.Metric{}
err := sl.metrics.targetScrapeNativeHistogramBucketLimit.Write(&metric)
require.NoError(t, err)
beforeMetricValue := metric.GetCounter().GetValue()
nativeHistogram := prometheus.NewHistogramVec(
prometheus.HistogramOpts{
Namespace: "testing",
Name: "example_native_histogram",
Help: "This is used for testing",
ConstLabels: map[string]string{"some": "value"},
NativeHistogramBucketFactor: 1.1, // 10% increase from bucket to bucket
NativeHistogramMaxBucketNumber: 100, // intentionally higher than the limit we'll use in the scraper
},
[]string{"size"},
)
registry := prometheus.NewRegistry()
registry.Register(nativeHistogram)
nativeHistogram.WithLabelValues("S").Observe(1.0)
nativeHistogram.WithLabelValues("M").Observe(1.0)
nativeHistogram.WithLabelValues("L").Observe(1.0)
nativeHistogram.WithLabelValues("M").Observe(10.0)
nativeHistogram.WithLabelValues("L").Observe(10.0) // in different bucket since > 1*1.1
gathered, err := registry.Gather()
require.NoError(t, err)
require.NotEmpty(t, gathered)
histogramMetricFamily := gathered[0]
msg, err := MetricFamilyToProtobuf(histogramMetricFamily)
require.NoError(t, err)
now := time.Now()
total, added, seriesAdded, err := sl.append(app, msg, "application/vnd.google.protobuf", now)
require.NoError(t, err)
require.Equal(t, 3, total)
require.Equal(t, 3, added)
require.Equal(t, 3, seriesAdded)
err = sl.metrics.targetScrapeNativeHistogramBucketLimit.Write(&metric)
require.NoError(t, err)
metricValue := metric.GetCounter().GetValue()
require.Equal(t, beforeMetricValue, metricValue)
beforeMetricValue = metricValue
nativeHistogram.WithLabelValues("L").Observe(100.0) // in different bucket since > 10*1.1
gathered, err = registry.Gather()
require.NoError(t, err)
require.NotEmpty(t, gathered)
histogramMetricFamily = gathered[0]
msg, err = MetricFamilyToProtobuf(histogramMetricFamily)
require.NoError(t, err)
now = time.Now()
total, added, seriesAdded, err = sl.append(app, msg, "application/vnd.google.protobuf", now)
require.NoError(t, err)
require.Equal(t, 3, total)
require.Equal(t, 3, added)
require.Equal(t, 3, seriesAdded)
err = sl.metrics.targetScrapeNativeHistogramBucketLimit.Write(&metric)
require.NoError(t, err)
metricValue = metric.GetCounter().GetValue()
require.Equal(t, beforeMetricValue, metricValue)
beforeMetricValue = metricValue
nativeHistogram.WithLabelValues("L").Observe(100000.0) // in different bucket since > 10*1.1
gathered, err = registry.Gather()
require.NoError(t, err)
require.NotEmpty(t, gathered)
histogramMetricFamily = gathered[0]
msg, err = MetricFamilyToProtobuf(histogramMetricFamily)
require.NoError(t, err)
now = time.Now()
total, added, seriesAdded, err = sl.append(app, msg, "application/vnd.google.protobuf", now)
if !errors.Is(err, errBucketLimit) {
t.Fatalf("Did not see expected histogram bucket limit error: %s", err)
}
require.NoError(t, app.Rollback())
require.Equal(t, 3, total)
require.Equal(t, 3, added)
require.Equal(t, 0, seriesAdded)
err = sl.metrics.targetScrapeNativeHistogramBucketLimit.Write(&metric)
require.NoError(t, err)
metricValue = metric.GetCounter().GetValue()
require.Equal(t, beforeMetricValue+1, metricValue)
}
func TestScrapeLoop_ChangingMetricString(t *testing.T) {
// This is a regression test for the scrape loop cache not properly maintaining
// IDs when the string representation of a metric changes across a scrape. Thus
// we use a real storage appender here.
s := teststorage.New(t)
defer s.Close()
capp := &collectResultAppender{}
sl := newBasicScrapeLoop(t, context.Background(), nil, func(ctx context.Context) storage.Appender { return capp }, 0)
now := time.Now()
slApp := sl.appender(context.Background())
_, _, _, err := sl.append(slApp, []byte(`metric_a{a="1",b="1"} 1`), "", now)
require.NoError(t, err)
require.NoError(t, slApp.Commit())
slApp = sl.appender(context.Background())
_, _, _, err = sl.append(slApp, []byte(`metric_a{b="1",a="1"} 2`), "", now.Add(time.Minute))
require.NoError(t, err)
require.NoError(t, slApp.Commit())
want := []floatSample{
{
metric: labels.FromStrings("__name__", "metric_a", "a", "1", "b", "1"),
t: timestamp.FromTime(now),
f: 1,
},
{
metric: labels.FromStrings("__name__", "metric_a", "a", "1", "b", "1"),
t: timestamp.FromTime(now.Add(time.Minute)),
f: 2,
},
}
require.Equal(t, want, capp.resultFloats, "Appended samples not as expected:\n%s", appender)
}
func TestScrapeLoopAppendStaleness(t *testing.T) {
app := &collectResultAppender{}
sl := newBasicScrapeLoop(t, context.Background(), nil, func(ctx context.Context) storage.Appender { return app }, 0)
now := time.Now()
slApp := sl.appender(context.Background())
_, _, _, err := sl.append(slApp, []byte("metric_a 1\n"), "", now)
require.NoError(t, err)
require.NoError(t, slApp.Commit())
slApp = sl.appender(context.Background())
_, _, _, err = sl.append(slApp, []byte(""), "", now.Add(time.Second))
require.NoError(t, err)
require.NoError(t, slApp.Commit())
want := []floatSample{
{
metric: labels.FromStrings(model.MetricNameLabel, "metric_a"),
t: timestamp.FromTime(now),
f: 1,
},
{
metric: labels.FromStrings(model.MetricNameLabel, "metric_a"),
t: timestamp.FromTime(now.Add(time.Second)),
f: math.Float64frombits(value.StaleNaN),
},
}
requireEqual(t, want, app.resultFloats, "Appended samples not as expected:\n%s", appender)
}
func TestScrapeLoopAppendNoStalenessIfTimestamp(t *testing.T) {
app := &collectResultAppender{}
sl := newBasicScrapeLoop(t, context.Background(), nil, func(ctx context.Context) storage.Appender { return app }, 0)
now := time.Now()
slApp := sl.appender(context.Background())
_, _, _, err := sl.append(slApp, []byte("metric_a 1 1000\n"), "", now)
require.NoError(t, err)
require.NoError(t, slApp.Commit())
slApp = sl.appender(context.Background())
_, _, _, err = sl.append(slApp, []byte(""), "", now.Add(time.Second))
require.NoError(t, err)
require.NoError(t, slApp.Commit())
want := []floatSample{
{
metric: labels.FromStrings(model.MetricNameLabel, "metric_a"),
t: 1000,
f: 1,
},
}
require.Equal(t, want, app.resultFloats, "Appended samples not as expected:\n%s", appender)
}
func TestScrapeLoopAppendStalenessIfTrackTimestampStaleness(t *testing.T) {
app := &collectResultAppender{}
sl := newBasicScrapeLoop(t, context.Background(), nil, func(ctx context.Context) storage.Appender { return app }, 0)
sl.trackTimestampsStaleness = true
now := time.Now()
slApp := sl.appender(context.Background())
_, _, _, err := sl.append(slApp, []byte("metric_a 1 1000\n"), "", now)
require.NoError(t, err)
require.NoError(t, slApp.Commit())
slApp = sl.appender(context.Background())
_, _, _, err = sl.append(slApp, []byte(""), "", now.Add(time.Second))
require.NoError(t, err)
require.NoError(t, slApp.Commit())
want := []floatSample{
{
metric: labels.FromStrings(model.MetricNameLabel, "metric_a"),
t: 1000,
f: 1,
},
{
metric: labels.FromStrings(model.MetricNameLabel, "metric_a"),
t: timestamp.FromTime(now.Add(time.Second)),
f: math.Float64frombits(value.StaleNaN),
},
}
requireEqual(t, want, app.resultFloats, "Appended samples not as expected:\n%s", appender)
}
func TestScrapeLoopAppendExemplar(t *testing.T) {
tests := []struct {
title string
scrapeClassicHistograms bool
enableNativeHistogramsIngestion bool
scrapeText string
contentType string
discoveryLabels []string
floats []floatSample
histograms []histogramSample
exemplars []exemplar.Exemplar
}{
{
title: "Metric without exemplars",
scrapeText: "metric_total{n=\"1\"} 0\n# EOF",
contentType: "application/openmetrics-text",
discoveryLabels: []string{"n", "2"},
floats: []floatSample{{
metric: labels.FromStrings("__name__", "metric_total", "exported_n", "1", "n", "2"),
f: 0,
}},
},
{
title: "Metric with exemplars",
scrapeText: "metric_total{n=\"1\"} 0 # {a=\"abc\"} 1.0\n# EOF",
contentType: "application/openmetrics-text",
discoveryLabels: []string{"n", "2"},
floats: []floatSample{{
metric: labels.FromStrings("__name__", "metric_total", "exported_n", "1", "n", "2"),
f: 0,
}},
exemplars: []exemplar.Exemplar{
{Labels: labels.FromStrings("a", "abc"), Value: 1},
},
},
{
title: "Metric with exemplars and TS",
scrapeText: "metric_total{n=\"1\"} 0 # {a=\"abc\"} 1.0 10000\n# EOF",
contentType: "application/openmetrics-text",
discoveryLabels: []string{"n", "2"},
floats: []floatSample{{
metric: labels.FromStrings("__name__", "metric_total", "exported_n", "1", "n", "2"),
f: 0,
}},
exemplars: []exemplar.Exemplar{
{Labels: labels.FromStrings("a", "abc"), Value: 1, Ts: 10000000, HasTs: true},
},
},
{
title: "Two metrics and exemplars",
scrapeText: `metric_total{n="1"} 1 # {t="1"} 1.0 10000
metric_total{n="2"} 2 # {t="2"} 2.0 20000
# EOF`,
contentType: "application/openmetrics-text",
floats: []floatSample{{
metric: labels.FromStrings("__name__", "metric_total", "n", "1"),
f: 1,
}, {
metric: labels.FromStrings("__name__", "metric_total", "n", "2"),
f: 2,
}},
exemplars: []exemplar.Exemplar{
{Labels: labels.FromStrings("t", "1"), Value: 1, Ts: 10000000, HasTs: true},
{Labels: labels.FromStrings("t", "2"), Value: 2, Ts: 20000000, HasTs: true},
},
},
{
title: "Native histogram with three exemplars",
enableNativeHistogramsIngestion: true,
scrapeText: `name: "test_histogram"
help: "Test histogram with many buckets removed to keep it manageable in size."
type: HISTOGRAM
metric: <
histogram: <
sample_count: 175
sample_sum: 0.0008280461746287094
bucket: <
cumulative_count: 2
upper_bound: -0.0004899999999999998
>
bucket: <
cumulative_count: 4
upper_bound: -0.0003899999999999998
exemplar: <
label: <
name: "dummyID"
value: "59727"
>
value: -0.00039
timestamp: <
seconds: 1625851155
nanos: 146848499
>
>
>
bucket: <
cumulative_count: 16
upper_bound: -0.0002899999999999998
exemplar: <
label: <
name: "dummyID"
value: "5617"
>
value: -0.00029
>
>
bucket: <
cumulative_count: 32
upper_bound: -0.0001899999999999998
exemplar: <
label: <
name: "dummyID"
value: "58215"
>
value: -0.00019
timestamp: <
seconds: 1625851055
nanos: 146848599
>
>
>
schema: 3
zero_threshold: 2.938735877055719e-39
zero_count: 2
negative_span: <
offset: -162
length: 1
>
negative_span: <
offset: 23
length: 4
>
negative_delta: 1
negative_delta: 3
negative_delta: -2
negative_delta: -1
negative_delta: 1
positive_span: <
offset: -161
length: 1
>
positive_span: <
offset: 8
length: 3
>
positive_delta: 1
positive_delta: 2
positive_delta: -1
positive_delta: -1
>
timestamp_ms: 1234568
>
`,
contentType: "application/vnd.google.protobuf",
histograms: []histogramSample{{
t: 1234568,
h: &histogram.Histogram{
Count: 175,
ZeroCount: 2,
Sum: 0.0008280461746287094,
ZeroThreshold: 2.938735877055719e-39,
Schema: 3,
PositiveSpans: []histogram.Span{
{Offset: -161, Length: 1},
{Offset: 8, Length: 3},
},
NegativeSpans: []histogram.Span{
{Offset: -162, Length: 1},
{Offset: 23, Length: 4},
},
PositiveBuckets: []int64{1, 2, -1, -1},
NegativeBuckets: []int64{1, 3, -2, -1, 1},
},
}},
exemplars: []exemplar.Exemplar{
// Native histogram exemplars are arranged by timestamp, and those with missing timestamps are dropped.
{Labels: labels.FromStrings("dummyID", "58215"), Value: -0.00019, Ts: 1625851055146, HasTs: true},
{Labels: labels.FromStrings("dummyID", "59727"), Value: -0.00039, Ts: 1625851155146, HasTs: true},
},
},
{
title: "Native histogram with three exemplars scraped as classic histogram",
enableNativeHistogramsIngestion: true,
scrapeText: `name: "test_histogram"
help: "Test histogram with many buckets removed to keep it manageable in size."
type: HISTOGRAM
metric: <
histogram: <
sample_count: 175
sample_sum: 0.0008280461746287094
bucket: <
cumulative_count: 2
upper_bound: -0.0004899999999999998
>
bucket: <
cumulative_count: 4
upper_bound: -0.0003899999999999998
exemplar: <
label: <
name: "dummyID"
value: "59727"
>
value: -0.00039
timestamp: <
seconds: 1625851155
nanos: 146848499
>
>
>
bucket: <
cumulative_count: 16
upper_bound: -0.0002899999999999998
exemplar: <
label: <
name: "dummyID"
value: "5617"
>
value: -0.00029
>
>
bucket: <
cumulative_count: 32
upper_bound: -0.0001899999999999998
exemplar: <
label: <
name: "dummyID"
value: "58215"
>
value: -0.00019
timestamp: <
seconds: 1625851055
nanos: 146848599
>
>
>
schema: 3
zero_threshold: 2.938735877055719e-39
zero_count: 2
negative_span: <
offset: -162
length: 1
>
negative_span: <
offset: 23
length: 4
>
negative_delta: 1
negative_delta: 3
negative_delta: -2
negative_delta: -1
negative_delta: 1
positive_span: <
offset: -161
length: 1
>
positive_span: <
offset: 8
length: 3
>
positive_delta: 1
positive_delta: 2
positive_delta: -1
positive_delta: -1
>
timestamp_ms: 1234568
>
`,
scrapeClassicHistograms: true,
contentType: "application/vnd.google.protobuf",
floats: []floatSample{
{metric: labels.FromStrings("__name__", "test_histogram_count"), t: 1234568, f: 175},
{metric: labels.FromStrings("__name__", "test_histogram_sum"), t: 1234568, f: 0.0008280461746287094},
{metric: labels.FromStrings("__name__", "test_histogram_bucket", "le", "-0.0004899999999999998"), t: 1234568, f: 2},
{metric: labels.FromStrings("__name__", "test_histogram_bucket", "le", "-0.0003899999999999998"), t: 1234568, f: 4},
{metric: labels.FromStrings("__name__", "test_histogram_bucket", "le", "-0.0002899999999999998"), t: 1234568, f: 16},
{metric: labels.FromStrings("__name__", "test_histogram_bucket", "le", "-0.0001899999999999998"), t: 1234568, f: 32},
{metric: labels.FromStrings("__name__", "test_histogram_bucket", "le", "+Inf"), t: 1234568, f: 175},
},
histograms: []histogramSample{{
t: 1234568,
h: &histogram.Histogram{
Count: 175,
ZeroCount: 2,
Sum: 0.0008280461746287094,
ZeroThreshold: 2.938735877055719e-39,
Schema: 3,
PositiveSpans: []histogram.Span{
{Offset: -161, Length: 1},
{Offset: 8, Length: 3},
},
NegativeSpans: []histogram.Span{
{Offset: -162, Length: 1},
{Offset: 23, Length: 4},
},
PositiveBuckets: []int64{1, 2, -1, -1},
NegativeBuckets: []int64{1, 3, -2, -1, 1},
},
}},
exemplars: []exemplar.Exemplar{
// Native histogram one is arranged by timestamp.
// Exemplars with missing timestamps are dropped for native histograms.
{Labels: labels.FromStrings("dummyID", "58215"), Value: -0.00019, Ts: 1625851055146, HasTs: true},
{Labels: labels.FromStrings("dummyID", "59727"), Value: -0.00039, Ts: 1625851155146, HasTs: true},
// Classic histogram one is in order of appearance.
// Exemplars with missing timestamps are supported for classic histograms.
{Labels: labels.FromStrings("dummyID", "59727"), Value: -0.00039, Ts: 1625851155146, HasTs: true},
{Labels: labels.FromStrings("dummyID", "5617"), Value: -0.00029, Ts: 1234568, HasTs: false},
{Labels: labels.FromStrings("dummyID", "58215"), Value: -0.00019, Ts: 1625851055146, HasTs: true},
},
},
}
for _, test := range tests {
t.Run(test.title, func(t *testing.T) {
app := &collectResultAppender{}
discoveryLabels := &Target{
labels: labels.FromStrings(test.discoveryLabels...),
}
sl := newBasicScrapeLoop(t, context.Background(), nil, func(ctx context.Context) storage.Appender { return app }, 0)
sl.enableNativeHistogramIngestion = test.enableNativeHistogramsIngestion
sl.sampleMutator = func(l labels.Labels) labels.Labels {
return mutateSampleLabels(l, discoveryLabels, false, nil)
}
sl.reportSampleMutator = func(l labels.Labels) labels.Labels {
return mutateReportSampleLabels(l, discoveryLabels)
}
sl.scrapeClassicHistograms = test.scrapeClassicHistograms
now := time.Now()
for i := range test.floats {
if test.floats[i].t != 0 {
continue
}
test.floats[i].t = timestamp.FromTime(now)
}
// We need to set the timestamp for expected exemplars that does not have a timestamp.
for i := range test.exemplars {
if test.exemplars[i].Ts == 0 {
test.exemplars[i].Ts = timestamp.FromTime(now)
}
}
buf := &bytes.Buffer{}
if test.contentType == "application/vnd.google.protobuf" {
// In case of protobuf, we have to create the binary representation.
pb := &dto.MetricFamily{}
// From text to proto message.
require.NoError(t, proto.UnmarshalText(test.scrapeText, pb))
// From proto message to binary protobuf.
protoBuf, err := proto.Marshal(pb)
require.NoError(t, err)
// Write first length, then binary protobuf.
varintBuf := binary.AppendUvarint(nil, uint64(len(protoBuf)))
buf.Write(varintBuf)
buf.Write(protoBuf)
} else {
buf.WriteString(test.scrapeText)
}
_, _, _, err := sl.append(app, buf.Bytes(), test.contentType, now)
require.NoError(t, err)
require.NoError(t, app.Commit())
requireEqual(t, test.floats, app.resultFloats)
requireEqual(t, test.histograms, app.resultHistograms)
requireEqual(t, test.exemplars, app.resultExemplars)
})
}
}
func TestScrapeLoopAppendExemplarSeries(t *testing.T) {
scrapeText := []string{`metric_total{n="1"} 1 # {t="1"} 1.0 10000
# EOF`, `metric_total{n="1"} 2 # {t="2"} 2.0 20000
# EOF`}
samples := []floatSample{{
metric: labels.FromStrings("__name__", "metric_total", "n", "1"),
f: 1,
}, {
metric: labels.FromStrings("__name__", "metric_total", "n", "1"),
f: 2,
}}
exemplars := []exemplar.Exemplar{
{Labels: labels.FromStrings("t", "1"), Value: 1, Ts: 10000000, HasTs: true},
{Labels: labels.FromStrings("t", "2"), Value: 2, Ts: 20000000, HasTs: true},
}
discoveryLabels := &Target{
labels: labels.FromStrings(),
}
app := &collectResultAppender{}
sl := newBasicScrapeLoop(t, context.Background(), nil, func(ctx context.Context) storage.Appender { return app }, 0)
sl.sampleMutator = func(l labels.Labels) labels.Labels {
return mutateSampleLabels(l, discoveryLabels, false, nil)
}
sl.reportSampleMutator = func(l labels.Labels) labels.Labels {
return mutateReportSampleLabels(l, discoveryLabels)
}
now := time.Now()
for i := range samples {
ts := now.Add(time.Second * time.Duration(i))
samples[i].t = timestamp.FromTime(ts)
}
// We need to set the timestamp for expected exemplars that does not have a timestamp.
for i := range exemplars {
if exemplars[i].Ts == 0 {
ts := now.Add(time.Second * time.Duration(i))
exemplars[i].Ts = timestamp.FromTime(ts)
}
}
for i, st := range scrapeText {
_, _, _, err := sl.append(app, []byte(st), "application/openmetrics-text", timestamp.Time(samples[i].t))
require.NoError(t, err)
require.NoError(t, app.Commit())
}
requireEqual(t, samples, app.resultFloats)
requireEqual(t, exemplars, app.resultExemplars)
}
func TestScrapeLoopRunReportsTargetDownOnScrapeError(t *testing.T) {
var (
scraper = &testScraper{}
appender = &collectResultAppender{}
app = func(ctx context.Context) storage.Appender { return appender }
)
ctx, cancel := context.WithCancel(context.Background())
sl := newBasicScrapeLoop(t, ctx, scraper, app, 10*time.Millisecond)
scraper.scrapeFunc = func(ctx context.Context, w io.Writer) error {
cancel()
return errors.New("scrape failed")
}
sl.run(nil)
require.Equal(t, 0.0, appender.resultFloats[0].f, "bad 'up' value")
}
func TestScrapeLoopRunReportsTargetDownOnInvalidUTF8(t *testing.T) {
var (
scraper = &testScraper{}
appender = &collectResultAppender{}
app = func(ctx context.Context) storage.Appender { return appender }
)
ctx, cancel := context.WithCancel(context.Background())
sl := newBasicScrapeLoop(t, ctx, scraper, app, 10*time.Millisecond)
scraper.scrapeFunc = func(ctx context.Context, w io.Writer) error {
cancel()
w.Write([]byte("a{l=\"\xff\"} 1\n"))
return nil
}
sl.run(nil)
require.Equal(t, 0.0, appender.resultFloats[0].f, "bad 'up' value")
}
type errorAppender struct {
collectResultAppender
}
func (app *errorAppender) Append(ref storage.SeriesRef, lset labels.Labels, t int64, v float64) (storage.SeriesRef, error) {
switch lset.Get(model.MetricNameLabel) {
case "out_of_order":
return 0, storage.ErrOutOfOrderSample
case "amend":
return 0, storage.ErrDuplicateSampleForTimestamp
case "out_of_bounds":
return 0, storage.ErrOutOfBounds
default:
return app.collectResultAppender.Append(ref, lset, t, v)
}
}
func TestScrapeLoopAppendGracefullyIfAmendOrOutOfOrderOrOutOfBounds(t *testing.T) {
app := &errorAppender{}
sl := newBasicScrapeLoop(t, context.Background(), nil, func(ctx context.Context) storage.Appender { return app }, 0)
now := time.Unix(1, 0)
slApp := sl.appender(context.Background())
total, added, seriesAdded, err := sl.append(slApp, []byte("out_of_order 1\namend 1\nnormal 1\nout_of_bounds 1\n"), "", now)
require.NoError(t, err)
require.NoError(t, slApp.Commit())
want := []floatSample{
{
metric: labels.FromStrings(model.MetricNameLabel, "normal"),
t: timestamp.FromTime(now),
f: 1,
},
}
requireEqual(t, want, app.resultFloats, "Appended samples not as expected:\n%s", appender)
require.Equal(t, 4, total)
require.Equal(t, 4, added)
require.Equal(t, 1, seriesAdded)
}
func TestScrapeLoopOutOfBoundsTimeError(t *testing.T) {
app := &collectResultAppender{}
sl := newBasicScrapeLoop(t, context.Background(), nil,
func(ctx context.Context) storage.Appender {
return &timeLimitAppender{
Appender: app,
maxTime: timestamp.FromTime(time.Now().Add(10 * time.Minute)),
}
},
0,
)
now := time.Now().Add(20 * time.Minute)
slApp := sl.appender(context.Background())
total, added, seriesAdded, err := sl.append(slApp, []byte("normal 1\n"), "", now)
require.NoError(t, err)
require.NoError(t, slApp.Commit())
require.Equal(t, 1, total)
require.Equal(t, 1, added)
require.Equal(t, 0, seriesAdded)
}
func TestTargetScraperScrapeOK(t *testing.T) {
const (
configTimeout = 1500 * time.Millisecond
expectedTimeout = "1.5"
)
var protobufParsing bool
var allowUTF8 bool
server := httptest.NewServer(
http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
accept := r.Header.Get("Accept")
if allowUTF8 {
require.Truef(t, strings.Contains(accept, "escaping=allow-utf-8"), "Expected Accept header to allow utf8, got %q", accept)
}
if protobufParsing {
require.True(t, strings.HasPrefix(accept, "application/vnd.google.protobuf;"),
"Expected Accept header to prefer application/vnd.google.protobuf.")
}
timeout := r.Header.Get("X-Prometheus-Scrape-Timeout-Seconds")
require.Equal(t, expectedTimeout, timeout, "Expected scrape timeout header.")
if allowUTF8 {
w.Header().Set("Content-Type", `text/plain; version=1.0.0; escaping=allow-utf-8`)
} else {
w.Header().Set("Content-Type", `text/plain; version=0.0.4`)
}
w.Write([]byte("metric_a 1\nmetric_b 2\n"))
}),
)
defer server.Close()
serverURL, err := url.Parse(server.URL)
if err != nil {
panic(err)
}
runTest := func(acceptHeader string) {
ts := &targetScraper{
Target: &Target{
labels: labels.FromStrings(
model.SchemeLabel, serverURL.Scheme,
model.AddressLabel, serverURL.Host,
),
},
client: http.DefaultClient,
timeout: configTimeout,
acceptHeader: acceptHeader,
}
var buf bytes.Buffer
resp, err := ts.scrape(context.Background())
require.NoError(t, err)
contentType, err := ts.readResponse(context.Background(), resp, &buf)
require.NoError(t, err)
if allowUTF8 {
require.Equal(t, "text/plain; version=1.0.0; escaping=allow-utf-8", contentType)
} else {
require.Equal(t, "text/plain; version=0.0.4", contentType)
}
require.Equal(t, "metric_a 1\nmetric_b 2\n", buf.String())
}
runTest(acceptHeader(config.DefaultScrapeProtocols, model.LegacyValidation))
protobufParsing = true
runTest(acceptHeader(config.DefaultProtoFirstScrapeProtocols, model.LegacyValidation))
protobufParsing = false
allowUTF8 = true
runTest(acceptHeader(config.DefaultScrapeProtocols, model.UTF8Validation))
protobufParsing = true
runTest(acceptHeader(config.DefaultProtoFirstScrapeProtocols, model.UTF8Validation))
}
func TestTargetScrapeScrapeCancel(t *testing.T) {
block := make(chan struct{})
server := httptest.NewServer(
http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
<-block
}),
)
defer server.Close()
serverURL, err := url.Parse(server.URL)
if err != nil {
panic(err)
}
ts := &targetScraper{
Target: &Target{
labels: labels.FromStrings(
model.SchemeLabel, serverURL.Scheme,
model.AddressLabel, serverURL.Host,
),
},
client: http.DefaultClient,
acceptHeader: acceptHeader(config.DefaultGlobalConfig.ScrapeProtocols, model.LegacyValidation),
}
ctx, cancel := context.WithCancel(context.Background())
errc := make(chan error, 1)
go func() {
time.Sleep(1 * time.Second)
cancel()
}()
go func() {
_, err := ts.scrape(ctx)
switch {
case err == nil:
errc <- errors.New("Expected error but got nil")
case !errors.Is(ctx.Err(), context.Canceled):
errc <- fmt.Errorf("Expected context cancellation error but got: %w", ctx.Err())
default:
close(errc)
}
}()
select {
case <-time.After(5 * time.Second):
require.FailNow(t, "Scrape function did not return unexpectedly.")
case err := <-errc:
require.NoError(t, err)
}
// If this is closed in a defer above the function the test server
// doesn't terminate and the test doesn't complete.
close(block)
}
func TestTargetScrapeScrapeNotFound(t *testing.T) {
server := httptest.NewServer(
http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
w.WriteHeader(http.StatusNotFound)
}),
)
defer server.Close()
serverURL, err := url.Parse(server.URL)
if err != nil {
panic(err)
}
ts := &targetScraper{
Target: &Target{
labels: labels.FromStrings(
model.SchemeLabel, serverURL.Scheme,
model.AddressLabel, serverURL.Host,
),
},
client: http.DefaultClient,
acceptHeader: acceptHeader(config.DefaultGlobalConfig.ScrapeProtocols, model.LegacyValidation),
}
resp, err := ts.scrape(context.Background())
require.NoError(t, err)
_, err = ts.readResponse(context.Background(), resp, io.Discard)
require.Contains(t, err.Error(), "404", "Expected \"404 NotFound\" error but got: %s", err)
}
func TestTargetScraperBodySizeLimit(t *testing.T) {
const (
bodySizeLimit = 15
responseBody = "metric_a 1\nmetric_b 2\n"
)
var gzipResponse bool
server := httptest.NewServer(
http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", `text/plain; version=0.0.4`)
if gzipResponse {
w.Header().Set("Content-Encoding", "gzip")
gw := gzip.NewWriter(w)
defer gw.Close()
gw.Write([]byte(responseBody))
return
}
w.Write([]byte(responseBody))
}),
)
defer server.Close()
serverURL, err := url.Parse(server.URL)
if err != nil {
panic(err)
}
ts := &targetScraper{
Target: &Target{
labels: labels.FromStrings(
model.SchemeLabel, serverURL.Scheme,
model.AddressLabel, serverURL.Host,
),
},
client: http.DefaultClient,
bodySizeLimit: bodySizeLimit,
acceptHeader: acceptHeader(config.DefaultGlobalConfig.ScrapeProtocols, model.LegacyValidation),
metrics: newTestScrapeMetrics(t),
}
var buf bytes.Buffer
// Target response uncompressed body, scrape with body size limit.
resp, err := ts.scrape(context.Background())
require.NoError(t, err)
_, err = ts.readResponse(context.Background(), resp, &buf)
require.ErrorIs(t, err, errBodySizeLimit)
require.Equal(t, bodySizeLimit, buf.Len())
// Target response gzip compressed body, scrape with body size limit.
gzipResponse = true
buf.Reset()
resp, err = ts.scrape(context.Background())
require.NoError(t, err)
_, err = ts.readResponse(context.Background(), resp, &buf)
require.ErrorIs(t, err, errBodySizeLimit)
require.Equal(t, bodySizeLimit, buf.Len())
// Target response uncompressed body, scrape without body size limit.
gzipResponse = false
buf.Reset()
ts.bodySizeLimit = 0
resp, err = ts.scrape(context.Background())
require.NoError(t, err)
_, err = ts.readResponse(context.Background(), resp, &buf)
require.NoError(t, err)
require.Len(t, responseBody, buf.Len())
// Target response gzip compressed body, scrape without body size limit.
gzipResponse = true
buf.Reset()
resp, err = ts.scrape(context.Background())
require.NoError(t, err)
_, err = ts.readResponse(context.Background(), resp, &buf)
require.NoError(t, err)
require.Len(t, responseBody, buf.Len())
}
// testScraper implements the scraper interface and allows setting values
// returned by its methods. It also allows setting a custom scrape function.
type testScraper struct {
offsetDur time.Duration
lastStart time.Time
lastDuration time.Duration
lastError error
scrapeErr error
scrapeFunc func(context.Context, io.Writer) error
}
func (ts *testScraper) offset(time.Duration, uint64) time.Duration {
return ts.offsetDur
}
func (ts *testScraper) Report(start time.Time, duration time.Duration, err error) {
ts.lastStart = start
ts.lastDuration = duration
ts.lastError = err
}
func (ts *testScraper) scrape(ctx context.Context) (*http.Response, error) {
return nil, ts.scrapeErr
}
func (ts *testScraper) readResponse(ctx context.Context, resp *http.Response, w io.Writer) (string, error) {
if ts.scrapeFunc != nil {
return "", ts.scrapeFunc(ctx, w)
}
return "", ts.scrapeErr
}
func TestScrapeLoop_RespectTimestamps(t *testing.T) {
s := teststorage.New(t)
defer s.Close()
app := s.Appender(context.Background())
capp := &collectResultAppender{next: app}
sl := newBasicScrapeLoop(t, context.Background(), nil, func(ctx context.Context) storage.Appender { return capp }, 0)
now := time.Now()
slApp := sl.appender(context.Background())
_, _, _, err := sl.append(slApp, []byte(`metric_a{a="1",b="1"} 1 0`), "", now)
require.NoError(t, err)
require.NoError(t, slApp.Commit())
want := []floatSample{
{
metric: labels.FromStrings("__name__", "metric_a", "a", "1", "b", "1"),
t: 0,
f: 1,
},
}
require.Equal(t, want, capp.resultFloats, "Appended samples not as expected:\n%s", appender)
}
func TestScrapeLoop_DiscardTimestamps(t *testing.T) {
s := teststorage.New(t)
defer s.Close()
app := s.Appender(context.Background())
capp := &collectResultAppender{next: app}
sl := newBasicScrapeLoop(t, context.Background(), nil, func(ctx context.Context) storage.Appender { return capp }, 0)
sl.honorTimestamps = false
now := time.Now()
slApp := sl.appender(context.Background())
_, _, _, err := sl.append(slApp, []byte(`metric_a{a="1",b="1"} 1 0`), "", now)
require.NoError(t, err)
require.NoError(t, slApp.Commit())
want := []floatSample{
{
metric: labels.FromStrings("__name__", "metric_a", "a", "1", "b", "1"),
t: timestamp.FromTime(now),
f: 1,
},
}
require.Equal(t, want, capp.resultFloats, "Appended samples not as expected:\n%s", appender)
}
func TestScrapeLoopDiscardDuplicateLabels(t *testing.T) {
s := teststorage.New(t)
defer s.Close()
ctx, cancel := context.WithCancel(context.Background())
sl := newBasicScrapeLoop(t, ctx, &testScraper{}, s.Appender, 0)
defer cancel()
// We add a good and a bad metric to check that both are discarded.
slApp := sl.appender(ctx)
_, _, _, err := sl.append(slApp, []byte("test_metric{le=\"500\"} 1\ntest_metric{le=\"600\",le=\"700\"} 1\n"), "", time.Time{})
require.Error(t, err)
require.NoError(t, slApp.Rollback())
// We need to cycle staleness cache maps after a manual rollback. Otherwise they will have old entries in them,
// which would cause ErrDuplicateSampleForTimestamp errors on the next append.
sl.cache.iterDone(true)
q, err := s.Querier(time.Time{}.UnixNano(), 0)
require.NoError(t, err)
series := q.Select(ctx, false, nil, labels.MustNewMatcher(labels.MatchRegexp, "__name__", ".*"))
require.False(t, series.Next(), "series found in tsdb")
require.NoError(t, series.Err())
// We add a good metric to check that it is recorded.
slApp = sl.appender(ctx)
_, _, _, err = sl.append(slApp, []byte("test_metric{le=\"500\"} 1\n"), "", time.Time{})
require.NoError(t, err)
require.NoError(t, slApp.Commit())
q, err = s.Querier(time.Time{}.UnixNano(), 0)
require.NoError(t, err)
series = q.Select(ctx, false, nil, labels.MustNewMatcher(labels.MatchEqual, "le", "500"))
require.True(t, series.Next(), "series not found in tsdb")
require.NoError(t, series.Err())
require.False(t, series.Next(), "more than one series found in tsdb")
}
func TestScrapeLoopDiscardUnnamedMetrics(t *testing.T) {
s := teststorage.New(t)
defer s.Close()
app := s.Appender(context.Background())
ctx, cancel := context.WithCancel(context.Background())
sl := newBasicScrapeLoop(t, context.Background(), &testScraper{}, func(ctx context.Context) storage.Appender { return app }, 0)
sl.sampleMutator = func(l labels.Labels) labels.Labels {
if l.Has("drop") {
return labels.FromStrings("no", "name") // This label set will trigger an error.
}
return l
}
defer cancel()
slApp := sl.appender(context.Background())
_, _, _, err := sl.append(slApp, []byte("nok 1\nnok2{drop=\"drop\"} 1\n"), "", time.Time{})
require.Error(t, err)
require.NoError(t, slApp.Rollback())
require.Equal(t, errNameLabelMandatory, err)
q, err := s.Querier(time.Time{}.UnixNano(), 0)
require.NoError(t, err)
series := q.Select(ctx, false, nil, labels.MustNewMatcher(labels.MatchRegexp, "__name__", ".*"))
require.False(t, series.Next(), "series found in tsdb")
require.NoError(t, series.Err())
}
func TestReusableConfig(t *testing.T) {
variants := []*config.ScrapeConfig{
{
JobName: "prometheus",
ScrapeTimeout: model.Duration(15 * time.Second),
},
{
JobName: "httpd",
ScrapeTimeout: model.Duration(15 * time.Second),
},
{
JobName: "prometheus",
ScrapeTimeout: model.Duration(5 * time.Second),
},
{
JobName: "prometheus",
MetricsPath: "/metrics",
},
{
JobName: "prometheus",
MetricsPath: "/metrics2",
},
{
JobName: "prometheus",
ScrapeTimeout: model.Duration(5 * time.Second),
MetricsPath: "/metrics2",
},
{
JobName: "prometheus",
ScrapeInterval: model.Duration(5 * time.Second),
MetricsPath: "/metrics2",
},
{
JobName: "prometheus",
ScrapeInterval: model.Duration(5 * time.Second),
SampleLimit: 1000,
MetricsPath: "/metrics2",
},
}
match := [][]int{
{0, 2},
{4, 5},
{4, 6},
{4, 7},
{5, 6},
{5, 7},
{6, 7},
}
noMatch := [][]int{
{1, 2},
{0, 4},
{3, 4},
}
for i, m := range match {
require.True(t, reusableCache(variants[m[0]], variants[m[1]]), "match test %d", i)
require.True(t, reusableCache(variants[m[1]], variants[m[0]]), "match test %d", i)
require.True(t, reusableCache(variants[m[1]], variants[m[1]]), "match test %d", i)
require.True(t, reusableCache(variants[m[0]], variants[m[0]]), "match test %d", i)
}
for i, m := range noMatch {
require.False(t, reusableCache(variants[m[0]], variants[m[1]]), "not match test %d", i)
require.False(t, reusableCache(variants[m[1]], variants[m[0]]), "not match test %d", i)
}
}
func TestReuseScrapeCache(t *testing.T) {
var (
app = &nopAppendable{}
cfg = &config.ScrapeConfig{
JobName: "Prometheus",
ScrapeTimeout: model.Duration(5 * time.Second),
ScrapeInterval: model.Duration(5 * time.Second),
MetricsPath: "/metrics",
}
sp, _ = newScrapePool(cfg, app, 0, nil, nil, &Options{}, newTestScrapeMetrics(t))
t1 = &Target{
discoveredLabels: labels.FromStrings("labelNew", "nameNew", "labelNew1", "nameNew1", "labelNew2", "nameNew2"),
}
proxyURL, _ = url.Parse("http://localhost:2128")
)
defer sp.stop()
sp.sync([]*Target{t1})
steps := []struct {
keep bool
newConfig *config.ScrapeConfig
}{
{
keep: true,
newConfig: &config.ScrapeConfig{
JobName: "Prometheus",
ScrapeInterval: model.Duration(5 * time.Second),
ScrapeTimeout: model.Duration(5 * time.Second),
MetricsPath: "/metrics",
},
},
{
keep: false,
newConfig: &config.ScrapeConfig{
JobName: "Prometheus",
ScrapeInterval: model.Duration(5 * time.Second),
ScrapeTimeout: model.Duration(15 * time.Second),
MetricsPath: "/metrics2",
},
},
{
keep: true,
newConfig: &config.ScrapeConfig{
JobName: "Prometheus",
SampleLimit: 400,
ScrapeInterval: model.Duration(5 * time.Second),
ScrapeTimeout: model.Duration(15 * time.Second),
MetricsPath: "/metrics2",
},
},
{
keep: false,
newConfig: &config.ScrapeConfig{
JobName: "Prometheus",
HonorTimestamps: true,
SampleLimit: 400,
ScrapeInterval: model.Duration(5 * time.Second),
ScrapeTimeout: model.Duration(15 * time.Second),
MetricsPath: "/metrics2",
},
},
{
keep: true,
newConfig: &config.ScrapeConfig{
JobName: "Prometheus",
HonorTimestamps: true,
SampleLimit: 400,
HTTPClientConfig: config_util.HTTPClientConfig{
ProxyConfig: config_util.ProxyConfig{ProxyURL: config_util.URL{URL: proxyURL}},
},
ScrapeInterval: model.Duration(5 * time.Second),
ScrapeTimeout: model.Duration(15 * time.Second),
MetricsPath: "/metrics2",
},
},
{
keep: false,
newConfig: &config.ScrapeConfig{
JobName: "Prometheus",
HonorTimestamps: true,
HonorLabels: true,
SampleLimit: 400,
ScrapeInterval: model.Duration(5 * time.Second),
ScrapeTimeout: model.Duration(15 * time.Second),
MetricsPath: "/metrics2",
},
},
{
keep: false,
newConfig: &config.ScrapeConfig{
JobName: "Prometheus",
ScrapeInterval: model.Duration(5 * time.Second),
ScrapeTimeout: model.Duration(15 * time.Second),
MetricsPath: "/metrics",
LabelLimit: 1,
},
},
{
keep: false,
newConfig: &config.ScrapeConfig{
JobName: "Prometheus",
ScrapeInterval: model.Duration(5 * time.Second),
ScrapeTimeout: model.Duration(15 * time.Second),
MetricsPath: "/metrics",
LabelLimit: 15,
},
},
{
keep: false,
newConfig: &config.ScrapeConfig{
JobName: "Prometheus",
ScrapeInterval: model.Duration(5 * time.Second),
ScrapeTimeout: model.Duration(15 * time.Second),
MetricsPath: "/metrics",
LabelLimit: 15,
LabelNameLengthLimit: 5,
},
},
{
keep: false,
newConfig: &config.ScrapeConfig{
JobName: "Prometheus",
ScrapeInterval: model.Duration(5 * time.Second),
ScrapeTimeout: model.Duration(15 * time.Second),
MetricsPath: "/metrics",
LabelLimit: 15,
LabelNameLengthLimit: 5,
LabelValueLengthLimit: 7,
},
},
}
cacheAddr := func(sp *scrapePool) map[uint64]string {
r := make(map[uint64]string)
for fp, l := range sp.loops {
r[fp] = fmt.Sprintf("%p", l.getCache())
}
return r
}
for i, s := range steps {
initCacheAddr := cacheAddr(sp)
sp.reload(s.newConfig)
for fp, newCacheAddr := range cacheAddr(sp) {
if s.keep {
require.Equal(t, initCacheAddr[fp], newCacheAddr, "step %d: old cache and new cache are not the same", i)
} else {
require.NotEqual(t, initCacheAddr[fp], newCacheAddr, "step %d: old cache and new cache are the same", i)
}
}
initCacheAddr = cacheAddr(sp)
sp.reload(s.newConfig)
for fp, newCacheAddr := range cacheAddr(sp) {
require.Equal(t, initCacheAddr[fp], newCacheAddr, "step %d: reloading the exact config invalidates the cache", i)
}
}
}
func TestScrapeAddFast(t *testing.T) {
s := teststorage.New(t)
defer s.Close()
ctx, cancel := context.WithCancel(context.Background())
sl := newBasicScrapeLoop(t, ctx, &testScraper{}, s.Appender, 0)
defer cancel()
slApp := sl.appender(ctx)
_, _, _, err := sl.append(slApp, []byte("up 1\n"), "", time.Time{})
require.NoError(t, err)
require.NoError(t, slApp.Commit())
// Poison the cache. There is just one entry, and one series in the
// storage. Changing the ref will create a 'not found' error.
for _, v := range sl.getCache().series {
v.ref++
}
slApp = sl.appender(ctx)
_, _, _, err = sl.append(slApp, []byte("up 1\n"), "", time.Time{}.Add(time.Second))
require.NoError(t, err)
require.NoError(t, slApp.Commit())
}
func TestReuseCacheRace(t *testing.T) {
var (
app = &nopAppendable{}
cfg = &config.ScrapeConfig{
JobName: "Prometheus",
ScrapeTimeout: model.Duration(5 * time.Second),
ScrapeInterval: model.Duration(5 * time.Second),
MetricsPath: "/metrics",
}
buffers = pool.New(1e3, 100e6, 3, func(sz int) interface{} { return make([]byte, 0, sz) })
sp, _ = newScrapePool(cfg, app, 0, nil, buffers, &Options{}, newTestScrapeMetrics(t))
t1 = &Target{
discoveredLabels: labels.FromStrings("labelNew", "nameNew"),
}
)
defer sp.stop()
sp.sync([]*Target{t1})
start := time.Now()
for i := uint(1); i > 0; i++ {
if time.Since(start) > 5*time.Second {
break
}
sp.reload(&config.ScrapeConfig{
JobName: "Prometheus",
ScrapeTimeout: model.Duration(1 * time.Millisecond),
ScrapeInterval: model.Duration(1 * time.Millisecond),
MetricsPath: "/metrics",
SampleLimit: i,
})
}
}
func TestCheckAddError(t *testing.T) {
var appErrs appendErrors
sl := scrapeLoop{l: log.NewNopLogger(), metrics: newTestScrapeMetrics(t)}
sl.checkAddError(nil, storage.ErrOutOfOrderSample, nil, nil, &appErrs)
require.Equal(t, 1, appErrs.numOutOfOrder)
}
func TestScrapeReportSingleAppender(t *testing.T) {
s := teststorage.New(t)
defer s.Close()
var (
signal = make(chan struct{}, 1)
scraper = &testScraper{}
)
ctx, cancel := context.WithCancel(context.Background())
sl := newBasicScrapeLoop(t, ctx, scraper, s.Appender, 10*time.Millisecond)
numScrapes := 0
scraper.scrapeFunc = func(ctx context.Context, w io.Writer) error {
numScrapes++
if numScrapes%4 == 0 {
return fmt.Errorf("scrape failed")
}
w.Write([]byte("metric_a 44\nmetric_b 44\nmetric_c 44\nmetric_d 44\n"))
return nil
}
go func() {
sl.run(nil)
signal <- struct{}{}
}()
start := time.Now()
for time.Since(start) < 3*time.Second {
q, err := s.Querier(time.Time{}.UnixNano(), time.Now().UnixNano())
require.NoError(t, err)
series := q.Select(ctx, false, nil, labels.MustNewMatcher(labels.MatchRegexp, "__name__", ".+"))
c := 0
for series.Next() {
i := series.At().Iterator(nil)
for i.Next() != chunkenc.ValNone {
c++
}
}
require.Equal(t, 0, c%9, "Appended samples not as expected: %d", c)
q.Close()
}
cancel()
select {
case <-signal:
case <-time.After(5 * time.Second):
require.FailNow(t, "Scrape wasn't stopped.")
}
}
func TestScrapeReportLimit(t *testing.T) {
s := teststorage.New(t)
defer s.Close()
cfg := &config.ScrapeConfig{
JobName: "test",
SampleLimit: 5,
Scheme: "http",
ScrapeInterval: model.Duration(100 * time.Millisecond),
ScrapeTimeout: model.Duration(100 * time.Millisecond),
}
var (
scrapes int
scrapedTwice = make(chan bool)
)
ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
fmt.Fprint(w, "metric_a 44\nmetric_b 44\nmetric_c 44\nmetric_d 44\n")
scrapes++
if scrapes == 2 {
close(scrapedTwice)
}
}))
defer ts.Close()
sp, err := newScrapePool(cfg, s, 0, nil, nil, &Options{}, newTestScrapeMetrics(t))
require.NoError(t, err)
defer sp.stop()
testURL, err := url.Parse(ts.URL)
require.NoError(t, err)
sp.Sync([]*targetgroup.Group{
{
Targets: []model.LabelSet{{model.AddressLabel: model.LabelValue(testURL.Host)}},
},
})
select {
case <-time.After(5 * time.Second):
t.Fatalf("target was not scraped twice")
case <-scrapedTwice:
// If the target has been scraped twice, report samples from the first
// scrape have been inserted in the database.
}
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
q, err := s.Querier(time.Time{}.UnixNano(), time.Now().UnixNano())
require.NoError(t, err)
defer q.Close()
series := q.Select(ctx, false, nil, labels.MustNewMatcher(labels.MatchRegexp, "__name__", "up"))
var found bool
for series.Next() {
i := series.At().Iterator(nil)
for i.Next() == chunkenc.ValFloat {
_, v := i.At()
require.Equal(t, 1.0, v)
found = true
}
}
require.True(t, found)
}
func TestScrapeLoopLabelLimit(t *testing.T) {
tests := []struct {
title string
scrapeLabels string
discoveryLabels []string
labelLimits labelLimits
expectErr bool
}{
{
title: "Valid number of labels",
scrapeLabels: `metric{l1="1", l2="2"} 0`,
discoveryLabels: nil,
labelLimits: labelLimits{labelLimit: 5},
expectErr: false,
}, {
title: "Too many labels",
scrapeLabels: `metric{l1="1", l2="2", l3="3", l4="4", l5="5", l6="6"} 0`,
discoveryLabels: nil,
labelLimits: labelLimits{labelLimit: 5},
expectErr: true,
}, {
title: "Too many labels including discovery labels",
scrapeLabels: `metric{l1="1", l2="2", l3="3", l4="4"} 0`,
discoveryLabels: []string{"l5", "5", "l6", "6"},
labelLimits: labelLimits{labelLimit: 5},
expectErr: true,
}, {
title: "Valid labels name length",
scrapeLabels: `metric{l1="1", l2="2"} 0`,
discoveryLabels: nil,
labelLimits: labelLimits{labelNameLengthLimit: 10},
expectErr: false,
}, {
title: "Label name too long",
scrapeLabels: `metric{label_name_too_long="0"} 0`,
discoveryLabels: nil,
labelLimits: labelLimits{labelNameLengthLimit: 10},
expectErr: true,
}, {
title: "Discovery label name too long",
scrapeLabels: `metric{l1="1", l2="2"} 0`,
discoveryLabels: []string{"label_name_too_long", "0"},
labelLimits: labelLimits{labelNameLengthLimit: 10},
expectErr: true,
}, {
title: "Valid labels value length",
scrapeLabels: `metric{l1="1", l2="2"} 0`,
discoveryLabels: nil,
labelLimits: labelLimits{labelValueLengthLimit: 10},
expectErr: false,
}, {
title: "Label value too long",
scrapeLabels: `metric{l1="label_value_too_long"} 0`,
discoveryLabels: nil,
labelLimits: labelLimits{labelValueLengthLimit: 10},
expectErr: true,
}, {
title: "Discovery label value too long",
scrapeLabels: `metric{l1="1", l2="2"} 0`,
discoveryLabels: []string{"l1", "label_value_too_long"},
labelLimits: labelLimits{labelValueLengthLimit: 10},
expectErr: true,
},
}
for _, test := range tests {
app := &collectResultAppender{}
discoveryLabels := &Target{
labels: labels.FromStrings(test.discoveryLabels...),
}
sl := newBasicScrapeLoop(t, context.Background(), nil, func(ctx context.Context) storage.Appender { return app }, 0)
sl.sampleMutator = func(l labels.Labels) labels.Labels {
return mutateSampleLabels(l, discoveryLabels, false, nil)
}
sl.reportSampleMutator = func(l labels.Labels) labels.Labels {
return mutateReportSampleLabels(l, discoveryLabels)
}
sl.labelLimits = &test.labelLimits
slApp := sl.appender(context.Background())
_, _, _, err := sl.append(slApp, []byte(test.scrapeLabels), "", time.Now())
t.Logf("Test:%s", test.title)
if test.expectErr {
require.Error(t, err)
} else {
require.NoError(t, err)
require.NoError(t, slApp.Commit())
}
}
}
func TestTargetScrapeIntervalAndTimeoutRelabel(t *testing.T) {
interval, _ := model.ParseDuration("2s")
timeout, _ := model.ParseDuration("500ms")
config := &config.ScrapeConfig{
ScrapeInterval: interval,
ScrapeTimeout: timeout,
RelabelConfigs: []*relabel.Config{
{
SourceLabels: model.LabelNames{model.ScrapeIntervalLabel},
Regex: relabel.MustNewRegexp("2s"),
Replacement: "3s",
TargetLabel: model.ScrapeIntervalLabel,
Action: relabel.Replace,
},
{
SourceLabels: model.LabelNames{model.ScrapeTimeoutLabel},
Regex: relabel.MustNewRegexp("500ms"),
Replacement: "750ms",
TargetLabel: model.ScrapeTimeoutLabel,
Action: relabel.Replace,
},
},
}
sp, _ := newScrapePool(config, &nopAppendable{}, 0, nil, nil, &Options{}, newTestScrapeMetrics(t))
tgts := []*targetgroup.Group{
{
Targets: []model.LabelSet{{model.AddressLabel: "127.0.0.1:9090"}},
},
}
sp.Sync(tgts)
defer sp.stop()
require.Equal(t, "3s", sp.ActiveTargets()[0].labels.Get(model.ScrapeIntervalLabel))
require.Equal(t, "750ms", sp.ActiveTargets()[0].labels.Get(model.ScrapeTimeoutLabel))
}
// Testing whether we can remove trailing .0 from histogram 'le' and summary 'quantile' labels.
func TestLeQuantileReLabel(t *testing.T) {
simpleStorage := teststorage.New(t)
defer simpleStorage.Close()
config := &config.ScrapeConfig{
JobName: "test",
MetricRelabelConfigs: []*relabel.Config{
{
SourceLabels: model.LabelNames{"le", "__name__"},
Regex: relabel.MustNewRegexp("(\\d+)\\.0+;.*_bucket"),
Replacement: relabel.DefaultRelabelConfig.Replacement,
Separator: relabel.DefaultRelabelConfig.Separator,
TargetLabel: "le",
Action: relabel.Replace,
},
{
SourceLabels: model.LabelNames{"quantile"},
Regex: relabel.MustNewRegexp("(\\d+)\\.0+"),
Replacement: relabel.DefaultRelabelConfig.Replacement,
Separator: relabel.DefaultRelabelConfig.Separator,
TargetLabel: "quantile",
Action: relabel.Replace,
},
},
SampleLimit: 100,
Scheme: "http",
ScrapeInterval: model.Duration(100 * time.Millisecond),
ScrapeTimeout: model.Duration(100 * time.Millisecond),
}
metricsText := `
# HELP test_histogram This is a histogram with default buckets
# TYPE test_histogram histogram
test_histogram_bucket{address="0.0.0.0",port="5001",le="0.005"} 0
test_histogram_bucket{address="0.0.0.0",port="5001",le="0.01"} 0
test_histogram_bucket{address="0.0.0.0",port="5001",le="0.025"} 0
test_histogram_bucket{address="0.0.0.0",port="5001",le="0.05"} 0
test_histogram_bucket{address="0.0.0.0",port="5001",le="0.1"} 0
test_histogram_bucket{address="0.0.0.0",port="5001",le="0.25"} 0
test_histogram_bucket{address="0.0.0.0",port="5001",le="0.5"} 0
test_histogram_bucket{address="0.0.0.0",port="5001",le="1.0"} 0
test_histogram_bucket{address="0.0.0.0",port="5001",le="2.5"} 0
test_histogram_bucket{address="0.0.0.0",port="5001",le="5.0"} 0
test_histogram_bucket{address="0.0.0.0",port="5001",le="10.0"} 0
test_histogram_bucket{address="0.0.0.0",port="5001",le="+Inf"} 0
test_histogram_sum{address="0.0.0.0",port="5001"} 0
test_histogram_count{address="0.0.0.0",port="5001"} 0
# HELP test_summary Number of inflight requests sampled at a regular interval. Quantile buckets keep track of inflight requests over the last 60s.
# TYPE test_summary summary
test_summary{quantile="0.5"} 0
test_summary{quantile="0.9"} 0
test_summary{quantile="0.95"} 0
test_summary{quantile="0.99"} 0
test_summary{quantile="1.0"} 1
test_summary_sum 1
test_summary_count 199
`
// The expected "le" values do not have the trailing ".0".
expectedLeValues := []string{"0.005", "0.01", "0.025", "0.05", "0.1", "0.25", "0.5", "1", "2.5", "5", "10", "+Inf"}
// The expected "quantile" values do not have the trailing ".0".
expectedQuantileValues := []string{"0.5", "0.9", "0.95", "0.99", "1"}
scrapeCount := 0
scraped := make(chan bool)
ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
fmt.Fprint(w, metricsText)
scrapeCount++
if scrapeCount > 2 {
close(scraped)
}
}))
defer ts.Close()
sp, err := newScrapePool(config, simpleStorage, 0, nil, nil, &Options{}, newTestScrapeMetrics(t))
require.NoError(t, err)
defer sp.stop()
testURL, err := url.Parse(ts.URL)
require.NoError(t, err)
sp.Sync([]*targetgroup.Group{
{
Targets: []model.LabelSet{{model.AddressLabel: model.LabelValue(testURL.Host)}},
},
})
require.Len(t, sp.ActiveTargets(), 1)
select {
case <-time.After(5 * time.Second):
t.Fatalf("target was not scraped")
case <-scraped:
}
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
q, err := simpleStorage.Querier(time.Time{}.UnixNano(), time.Now().UnixNano())
require.NoError(t, err)
defer q.Close()
checkValues := func(labelName string, expectedValues []string, series storage.SeriesSet) {
foundLeValues := map[string]bool{}
for series.Next() {
s := series.At()
v := s.Labels().Get(labelName)
require.NotContains(t, foundLeValues, v, "duplicate label value found")
foundLeValues[v] = true
}
require.Equal(t, len(expectedValues), len(foundLeValues), "number of label values not as expected")
for _, v := range expectedValues {
require.Contains(t, foundLeValues, v, "label value not found")
}
}
series := q.Select(ctx, false, nil, labels.MustNewMatcher(labels.MatchRegexp, "__name__", "test_histogram_bucket"))
checkValues("le", expectedLeValues, series)
series = q.Select(ctx, false, nil, labels.MustNewMatcher(labels.MatchRegexp, "__name__", "test_summary"))
checkValues("quantile", expectedQuantileValues, series)
}
func TestScrapeLoopRunCreatesStaleMarkersOnFailedScrapeForTimestampedMetrics(t *testing.T) {
appender := &collectResultAppender{}
var (
signal = make(chan struct{}, 1)
scraper = &testScraper{}
app = func(ctx context.Context) storage.Appender { return appender }
)
ctx, cancel := context.WithCancel(context.Background())
sl := newBasicScrapeLoop(t, ctx, scraper, app, 10*time.Millisecond)
sl.trackTimestampsStaleness = true
// Succeed once, several failures, then stop.
numScrapes := 0
scraper.scrapeFunc = func(ctx context.Context, w io.Writer) error {
numScrapes++
switch numScrapes {
case 1:
w.Write([]byte(fmt.Sprintf("metric_a 42 %d\n", time.Now().UnixNano()/int64(time.Millisecond))))
return nil
case 5:
cancel()
}
return errors.New("scrape failed")
}
go func() {
sl.run(nil)
signal <- struct{}{}
}()
select {
case <-signal:
case <-time.After(5 * time.Second):
t.Fatalf("Scrape wasn't stopped.")
}
// 1 successfully scraped sample, 1 stale marker after first fail, 5 report samples for
// each scrape successful or not.
require.Len(t, appender.resultFloats, 27, "Appended samples not as expected:\n%s", appender)
require.Equal(t, 42.0, appender.resultFloats[0].f, "Appended first sample not as expected")
require.True(t, value.IsStaleNaN(appender.resultFloats[6].f),
"Appended second sample not as expected. Wanted: stale NaN Got: %x", math.Float64bits(appender.resultFloats[6].f))
}
func TestScrapeLoopCompression(t *testing.T) {
simpleStorage := teststorage.New(t)
defer simpleStorage.Close()
metricsText := makeTestMetrics(10)
for _, tc := range []struct {
enableCompression bool
acceptEncoding string
}{
{
enableCompression: true,
acceptEncoding: "gzip",
},
{
enableCompression: false,
acceptEncoding: "identity",
},
} {
t.Run(fmt.Sprintf("compression=%v,acceptEncoding=%s", tc.enableCompression, tc.acceptEncoding), func(t *testing.T) {
scraped := make(chan bool)
ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
require.Equal(t, tc.acceptEncoding, r.Header.Get("Accept-Encoding"), "invalid value of the Accept-Encoding header")
fmt.Fprint(w, metricsText)
close(scraped)
}))
defer ts.Close()
config := &config.ScrapeConfig{
JobName: "test",
SampleLimit: 100,
Scheme: "http",
ScrapeInterval: model.Duration(100 * time.Millisecond),
ScrapeTimeout: model.Duration(100 * time.Millisecond),
EnableCompression: tc.enableCompression,
}
sp, err := newScrapePool(config, simpleStorage, 0, nil, nil, &Options{}, newTestScrapeMetrics(t))
require.NoError(t, err)
defer sp.stop()
testURL, err := url.Parse(ts.URL)
require.NoError(t, err)
sp.Sync([]*targetgroup.Group{
{
Targets: []model.LabelSet{{model.AddressLabel: model.LabelValue(testURL.Host)}},
},
})
require.Len(t, sp.ActiveTargets(), 1)
select {
case <-time.After(5 * time.Second):
t.Fatalf("target was not scraped")
case <-scraped:
}
})
}
}
func TestPickSchema(t *testing.T) {
tcs := []struct {
factor float64
schema int32
}{
{
factor: 65536,
schema: -4,
},
{
factor: 256,
schema: -3,
},
{
factor: 16,
schema: -2,
},
{
factor: 4,
schema: -1,
},
{
factor: 2,
schema: 0,
},
{
factor: 1.4,
schema: 1,
},
{
factor: 1.1,
schema: 2,
},
{
factor: 1.09,
schema: 3,
},
{
factor: 1.04,
schema: 4,
},
{
factor: 1.02,
schema: 5,
},
{
factor: 1.01,
schema: 6,
},
{
factor: 1.005,
schema: 7,
},
{
factor: 1.002,
schema: 8,
},
// The default value of native_histogram_min_bucket_factor
{
factor: 0,
schema: 8,
},
}
for _, tc := range tcs {
schema := pickSchema(tc.factor)
require.Equal(t, tc.schema, schema)
}
}
func BenchmarkTargetScraperGzip(b *testing.B) {
scenarios := []struct {
metricsCount int
body []byte
}{
{metricsCount: 1},
{metricsCount: 100},
{metricsCount: 1000},
{metricsCount: 10000},
{metricsCount: 100000},
}
for i := 0; i < len(scenarios); i++ {
var buf bytes.Buffer
var name string
gw := gzip.NewWriter(&buf)
for j := 0; j < scenarios[i].metricsCount; j++ {
name = fmt.Sprintf("go_memstats_alloc_bytes_total_%d", j)
fmt.Fprintf(gw, "# HELP %s Total number of bytes allocated, even if freed.\n", name)
fmt.Fprintf(gw, "# TYPE %s counter\n", name)
fmt.Fprintf(gw, "%s %d\n", name, i*j)
}
gw.Close()
scenarios[i].body = buf.Bytes()
}
handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", `text/plain; version=0.0.4`)
w.Header().Set("Content-Encoding", "gzip")
for _, scenario := range scenarios {
if strconv.Itoa(scenario.metricsCount) == r.URL.Query()["count"][0] {
w.Write(scenario.body)
return
}
}
w.WriteHeader(http.StatusBadRequest)
})
server := httptest.NewServer(handler)
defer server.Close()
serverURL, err := url.Parse(server.URL)
if err != nil {
panic(err)
}
client, err := config_util.NewClientFromConfig(config_util.DefaultHTTPClientConfig, "test_job")
if err != nil {
panic(err)
}
for _, scenario := range scenarios {
b.Run(fmt.Sprintf("metrics=%d", scenario.metricsCount), func(b *testing.B) {
ts := &targetScraper{
Target: &Target{
labels: labels.FromStrings(
model.SchemeLabel, serverURL.Scheme,
model.AddressLabel, serverURL.Host,
),
params: url.Values{"count": []string{strconv.Itoa(scenario.metricsCount)}},
},
client: client,
timeout: time.Second,
}
b.ResetTimer()
for i := 0; i < b.N; i++ {
_, err = ts.scrape(context.Background())
require.NoError(b, err)
}
})
}
}
// When a scrape contains multiple instances for the same time series we should increment
// prometheus_target_scrapes_sample_duplicate_timestamp_total metric.
func TestScrapeLoopSeriesAddedDuplicates(t *testing.T) {
ctx, sl := simpleTestScrapeLoop(t)
slApp := sl.appender(ctx)
total, added, seriesAdded, err := sl.append(slApp, []byte("test_metric 1\ntest_metric 2\ntest_metric 3\n"), "", time.Time{})
require.NoError(t, err)
require.NoError(t, slApp.Commit())
require.Equal(t, 3, total)
require.Equal(t, 3, added)
require.Equal(t, 1, seriesAdded)
require.Equal(t, 2.0, prom_testutil.ToFloat64(sl.metrics.targetScrapeSampleDuplicate))
slApp = sl.appender(ctx)
total, added, seriesAdded, err = sl.append(slApp, []byte("test_metric 1\ntest_metric 1\ntest_metric 1\n"), "", time.Time{})
require.NoError(t, err)
require.NoError(t, slApp.Commit())
require.Equal(t, 3, total)
require.Equal(t, 3, added)
require.Equal(t, 0, seriesAdded)
require.Equal(t, 4.0, prom_testutil.ToFloat64(sl.metrics.targetScrapeSampleDuplicate))
// When different timestamps are supplied, multiple samples are accepted.
slApp = sl.appender(ctx)
total, added, seriesAdded, err = sl.append(slApp, []byte("test_metric 1 1001\ntest_metric 1 1002\ntest_metric 1 1003\n"), "", time.Time{})
require.NoError(t, err)
require.NoError(t, slApp.Commit())
require.Equal(t, 3, total)
require.Equal(t, 3, added)
require.Equal(t, 0, seriesAdded)
// Metric is not higher than last time.
require.Equal(t, 4.0, prom_testutil.ToFloat64(sl.metrics.targetScrapeSampleDuplicate))
}
// This tests running a full scrape loop and checking that the scrape option
// `native_histogram_min_bucket_factor` is used correctly.
func TestNativeHistogramMaxSchemaSet(t *testing.T) {
testcases := map[string]struct {
minBucketFactor string
expectedSchema int32
}{
"min factor not specified": {
minBucketFactor: "",
expectedSchema: 3, // Factor 1.09.
},
"min factor 1": {
minBucketFactor: "native_histogram_min_bucket_factor: 1",
expectedSchema: 3, // Factor 1.09.
},
"min factor 2": {
minBucketFactor: "native_histogram_min_bucket_factor: 2",
expectedSchema: 0, // Factor 2.00.
},
}
for name, tc := range testcases {
t.Run(name, func(t *testing.T) {
testNativeHistogramMaxSchemaSet(t, tc.minBucketFactor, tc.expectedSchema)
})
}
}
func testNativeHistogramMaxSchemaSet(t *testing.T, minBucketFactor string, expectedSchema int32) {
// Create a ProtoBuf message to serve as a Prometheus metric.
nativeHistogram := prometheus.NewHistogram(
prometheus.HistogramOpts{
Namespace: "testing",
Name: "example_native_histogram",
Help: "This is used for testing",
NativeHistogramBucketFactor: 1.1,
NativeHistogramMaxBucketNumber: 100,
},
)
registry := prometheus.NewRegistry()
registry.Register(nativeHistogram)
nativeHistogram.Observe(1.0)
nativeHistogram.Observe(1.0)
nativeHistogram.Observe(1.0)
nativeHistogram.Observe(10.0) // in different bucket since > 1*1.1.
nativeHistogram.Observe(10.0)
gathered, err := registry.Gather()
require.NoError(t, err)
require.NotEmpty(t, gathered)
histogramMetricFamily := gathered[0]
buffer := protoMarshalDelimited(t, histogramMetricFamily)
// Create a HTTP server to serve /metrics via ProtoBuf
metricsServer := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", `application/vnd.google.protobuf; proto=io.prometheus.client.MetricFamily; encoding=delimited`)
w.Write(buffer)
}))
defer metricsServer.Close()
// Create a scrape loop with the HTTP server as the target.
configStr := fmt.Sprintf(`
global:
scrape_interval: 1s
scrape_timeout: 1s
scrape_configs:
- job_name: test
%s
static_configs:
- targets: [%s]
`, minBucketFactor, strings.ReplaceAll(metricsServer.URL, "http://", ""))
s := teststorage.New(t)
defer s.Close()
s.DB.EnableNativeHistograms()
reg := prometheus.NewRegistry()
mng, err := NewManager(&Options{EnableNativeHistogramsIngestion: true}, nil, nil, s, reg)
require.NoError(t, err)
cfg, err := config.Load(configStr, false, log.NewNopLogger())
require.NoError(t, err)
mng.ApplyConfig(cfg)
tsets := make(chan map[string][]*targetgroup.Group)
go func() {
err = mng.Run(tsets)
require.NoError(t, err)
}()
defer mng.Stop()
// Get the static targets and apply them to the scrape manager.
require.Len(t, cfg.ScrapeConfigs, 1)
scrapeCfg := cfg.ScrapeConfigs[0]
require.Len(t, scrapeCfg.ServiceDiscoveryConfigs, 1)
staticDiscovery, ok := scrapeCfg.ServiceDiscoveryConfigs[0].(discovery.StaticConfig)
require.True(t, ok)
require.Len(t, staticDiscovery, 1)
tsets <- map[string][]*targetgroup.Group{"test": staticDiscovery}
// Wait for the scrape loop to scrape the target.
require.Eventually(t, func() bool {
q, err := s.Querier(0, math.MaxInt64)
require.NoError(t, err)
seriesS := q.Select(context.Background(), false, nil, labels.MustNewMatcher(labels.MatchEqual, "__name__", "testing_example_native_histogram"))
countSeries := 0
for seriesS.Next() {
countSeries++
}
return countSeries > 0
}, 15*time.Second, 100*time.Millisecond)
// Check that native histogram schema is as expected.
q, err := s.Querier(0, math.MaxInt64)
require.NoError(t, err)
seriesS := q.Select(context.Background(), false, nil, labels.MustNewMatcher(labels.MatchEqual, "__name__", "testing_example_native_histogram"))
histogramSamples := []*histogram.Histogram{}
for seriesS.Next() {
series := seriesS.At()
it := series.Iterator(nil)
for vt := it.Next(); vt != chunkenc.ValNone; vt = it.Next() {
if vt != chunkenc.ValHistogram {
// don't care about other samples
continue
}
_, h := it.AtHistogram(nil)
histogramSamples = append(histogramSamples, h)
}
}
require.NoError(t, seriesS.Err())
require.NotEmpty(t, histogramSamples)
for _, h := range histogramSamples {
require.Equal(t, expectedSchema, h.Schema)
}
}