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Prepare for multiple text formats

Browse source 
Pass content type down to text parser.

Add layer of indirection in front of text parser,
and rename to avoid future clashes.

Signed-off-by: Brian Brazil <brian.brazil@robustperception.io>
This commit is contained in:
Brian Brazil 2018-10-04 14:52:03 +01:00
parent 5824d6902d
commit ffe7efb411
10 changed files with 161 additions and 106 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

3
Makefile
View file

@ -17,8 +17,7 @@ STATICCHECK_IGNORE = \
github.com/prometheus/prometheus/discovery/kubernetes/kubernetes.go:SA1019 \
github.com/prometheus/prometheus/discovery/kubernetes/node.go:SA1019 \
github.com/prometheus/prometheus/documentation/examples/remote_storage/remote_storage_adapter/main.go:SA1019 \
github.com/prometheus/prometheus/pkg/textparse/lex.l.go:SA4006 \
github.com/prometheus/prometheus/pkg/textparse/lex.l.go:SA4006 \
github.com/prometheus/prometheus/pkg/textparse/promlex.l.go:SA4006 \
github.com/prometheus/prometheus/pkg/pool/pool.go:SA6002 \
github.com/prometheus/prometheus/promql/engine.go:SA6002 \
github.com/prometheus/prometheus/prompb/rpc.pb.gw.go:SA1019

76
pkg/textparse/interface.go Normal file
View file

@ -0,0 +1,76 @@
// Copyright 2017 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 textparse
import (
"github.com/prometheus/prometheus/pkg/labels"
)
// Parser parses samples from a byte slice of samples in the official
// Prometheus text exposition format.
type Parser interface {
// Series returns the bytes of the series, the timestamp if set, and the value
// of the current sample.
Series() ([]byte, *int64, float64)
// Help returns the metric name and help text in the current entry.
// Must only be called after Next returned a help entry.
// The returned byte slices become invalid after the next call to Next.
Help() ([]byte, []byte)
// Type returns the metric name and type in the current entry.
// Must only be called after Next returned a type entry.
// The returned byte slices become invalid after the next call to Next.
Type() ([]byte, MetricType)
// Comment returns the text of the current comment.
// Must only be called after Next returned a comment entry.
// The returned byte slice becomes invalid after the next call to Next.
Comment() []byte
// Metric writes the labels of the current sample into the passed labels.
// It returns the string from which the metric was parsed.
Metric(l *labels.Labels) string
// Next advances the parser to the next sample. It returns false if no
// more samples were read or an error occurred.
Next() (Entry, error)
}
// New returns a new parser of the byte slice.
func New(b []byte, contentType string) Parser {
return NewPromParser(b)
}
// Entry represents the type of a parsed entry.
type Entry int
const (
EntryInvalid Entry = -1
EntryType Entry = 0
EntryHelp Entry = 1
EntrySeries Entry = 2
EntryComment Entry = 3
)
// MetricType represents metric type values.
type MetricType string
const (
MetricTypeCounter = "counter"
MetricTypeGauge = "gauge"
MetricTypeHistogram = "histogram"
MetricTypeSummary = "summary"
MetricTypeUntyped = "untyped"
)

4
pkg/textparse/lex.l → pkg/textparse/promlex.l
View file

@ -32,7 +32,7 @@ const (
// Lex is called by the parser generated by "go tool yacc" to obtain each
// token. The method is opened before the matching rules block and closed at
// the end of the file.
func (l *lexer) Lex() token {
func (l *promlexer) Lex() token {
if l.i >= len(l.b) {
return tEOF
}
@ -87,7 +87,7 @@ C [^\n]
return tInvalid
}
func (l *lexer) consumeComment() token {
func (l *promlexer) consumeComment() token {
for c := l.cur(); ; c = l.next() {
switch c {
case 0:

6
pkg/textparse/lex.l.go → pkg/textparse/promlex.l.go
View file

@ -1,4 +1,4 @@
// CAUTION: Generated file - DO NOT EDIT.
// Code generated by golex. DO NOT EDIT.
// Copyright 2017 The Prometheus Authors
// Licensed under the Apache License, Version 2.0 (the "License");
@ -33,7 +33,7 @@ const (
// Lex is called by the parser generated by "go tool yacc" to obtain each
// token. The method is opened before the matching rules block and closed at
// the end of the file.
func (l *lexer) Lex() token {
func (l *promlexer) Lex() token {
if l.i >= len(l.b) {
return tEOF
}
@ -537,7 +537,7 @@ yyabort: // no lexem recognized
return tInvalid
}
func (l *lexer) consumeComment() token {
func (l *promlexer) consumeComment() token {
for c := l.cur(); ; c = l.next() {
switch c {
case 0:

67
pkg/textparse/parse.go → pkg/textparse/promparse.go
View file

@ -12,9 +12,8 @@
// limitations under the License.
//go:generate go get github.com/cznic/golex
//go:generate golex -o=lex.l.go lex.l
//go:generate golex -o=promlex.l.go promlex.l
// Package textparse contains an efficient parser for the Prometheus text format.
package textparse
import (
@ -32,7 +31,7 @@ import (
"github.com/prometheus/prometheus/pkg/value"
)
type lexer struct {
type promlexer struct {
b []byte
i int
start int
@ -106,16 +105,16 @@ func (t token) String() string {
}
// buf returns the buffer of the current token.
func (l *lexer) buf() []byte {
func (l *promlexer) buf() []byte {
return l.b[l.start:l.i]
}
func (l *lexer) cur() byte {
func (l *promlexer) cur() byte {
return l.b[l.i]
}
// next advances the lexer to the next character.
func (l *lexer) next() byte {
// next advances the promlexer to the next character.
func (l *promlexer) next() byte {
l.i++
if l.i >= len(l.b) {
l.err = io.EOF
@ -129,14 +128,14 @@ func (l *lexer) next() byte {
return l.b[l.i]
}
func (l *lexer) Error(es string) {
func (l *promlexer) Error(es string) {
l.err = errors.New(es)
}
// Parser parses samples from a byte slice of samples in the official
// PromParser parses samples from a byte slice of samples in the official
// Prometheus text exposition format.
type Parser struct {
l *lexer
type PromParser struct {
l *promlexer
series []byte
text []byte
mtype MetricType
@ -148,13 +147,13 @@ type Parser struct {
}
// New returns a new parser of the byte slice.
func New(b []byte) *Parser {
return &Parser{l: &lexer{b: append(b, '\n')}}
func NewPromParser(b []byte) Parser {
return &PromParser{l: &promlexer{b: append(b, '\n')}}
}
// Series returns the bytes of the series, the timestamp if set, and the value
// of the current sample.
func (p *Parser) Series() ([]byte, *int64, float64) {
func (p *PromParser) Series() ([]byte, *int64, float64) {
if p.hasTS {
return p.series, &p.ts, p.val
}
@ -164,7 +163,7 @@ func (p *Parser) Series() ([]byte, *int64, float64) {
// Help returns the metric name and help text in the current entry.
// Must only be called after Next returned a help entry.
// The returned byte slices become invalid after the next call to Next.
func (p *Parser) Help() ([]byte, []byte) {
func (p *PromParser) Help() ([]byte, []byte) {
m := p.l.b[p.offsets[0]:p.offsets[1]]
// Replacer causes allocations. Replace only when necessary.
@ -177,20 +176,20 @@ func (p *Parser) Help() ([]byte, []byte) {
// Type returns the metric name and type in the current entry.
// Must only be called after Next returned a type entry.
// The returned byte slices become invalid after the next call to Next.
func (p *Parser) Type() ([]byte, MetricType) {
func (p *PromParser) Type() ([]byte, MetricType) {
return p.l.b[p.offsets[0]:p.offsets[1]], p.mtype
}
// Comment returns the text of the current comment.
// Must only be called after Next returned a comment entry.
// The returned byte slice becomes invalid after the next call to Next.
func (p *Parser) Comment() []byte {
func (p *PromParser) Comment() []byte {
return p.text
}
// Metric writes the labels of the current sample into the passed labels.
// It returns the string from which the metric was parsed.
func (p *Parser) Metric(l *labels.Labels) string {
func (p *PromParser) Metric(l *labels.Labels) string {
// Allocate the full immutable string immediately, so we just
// have to create references on it below.
s := string(p.series)
@ -221,9 +220,9 @@ func (p *Parser) Metric(l *labels.Labels) string {
return s
}
// nextToken returns the next token from the lexer. It skips over tabs
// nextToken returns the next token from the promlexer. It skips over tabs
// and spaces.
func (p *Parser) nextToken() token {
func (p *PromParser) nextToken() token {
for {
if tok := p.l.Lex(); tok != tWhitespace {
return tok
@ -231,35 +230,13 @@ func (p *Parser) nextToken() token {
}
}
// Entry represents the type of a parsed entry.
type Entry int
const (
EntryInvalid Entry = -1
EntryType Entry = 0
EntryHelp Entry = 1
EntrySeries Entry = 2
EntryComment Entry = 3
)
// MetricType represents metric type values.
type MetricType string
const (
MetricTypeCounter = "counter"
MetricTypeGauge = "gauge"
MetricTypeHistogram = "histogram"
MetricTypeSummary = "summary"
MetricTypeUntyped = "untyped"
)
func parseError(exp string, got token) error {
return fmt.Errorf("%s, got %q", exp, got)
}
// Next advances the parser to the next sample. It returns false if no
// more samples were read or an error occurred.
func (p *Parser) Next() (Entry, error) {
func (p *PromParser) Next() (Entry, error) {
var err error
p.start = p.l.i
@ -371,7 +348,7 @@ func (p *Parser) Next() (Entry, error) {
return EntryInvalid, err
}
func (p *Parser) parseLVals() error {
func (p *PromParser) parseLVals() error {
t := p.nextToken()
for {
switch t {
@ -393,7 +370,7 @@ func (p *Parser) parseLVals() error {
return fmt.Errorf("invalid UTF-8 label value")
}
// The lexer ensures the value string is quoted. Strip first
// The promlexer ensures the value string is quoted. Strip first
// and last character.
p.offsets = append(p.offsets, p.l.start+1, p.l.i-1)

44
pkg/textparse/parse_test.go → pkg/textparse/promparse_test.go
View file

@ -27,7 +27,7 @@ import (
"github.com/stretchr/testify/require"
)
func TestParse(t *testing.T) {
func TestPromParse(t *testing.T) {
input := `# HELP go_gc_duration_seconds A summary of the GC invocation durations.
# TYPE go_gc_duration_seconds summary
go_gc_duration_seconds{quantile="0"} 4.9351e-05
@ -164,7 +164,7 @@ testmetric{label="\"bar\""} 1`
},
}
p := New([]byte(input))
p := NewPromParser([]byte(input))
i := 0
var res labels.Labels
@ -207,7 +207,7 @@ testmetric{label="\"bar\""} 1`
require.Equal(t, len(exp), i)
}
func TestParseErrors(t *testing.T) {
func TestPromParseErrors(t *testing.T) {
cases := []struct {
input string
err string
@ -247,7 +247,7 @@ func TestParseErrors(t *testing.T) {
}
for i, c := range cases {
p := New([]byte(c.input))
p := NewPromParser([]byte(c.input))
var err error
for err == nil {
_, err = p.Next()
@ -257,7 +257,7 @@ func TestParseErrors(t *testing.T) {
}
}
func TestNullByteHandling(t *testing.T) {
func TestPromNullByteHandling(t *testing.T) {
cases := []struct {
input string
err string
@ -297,7 +297,7 @@ func TestNullByteHandling(t *testing.T) {
}
for i, c := range cases {
p := New([]byte(c.input))
p := NewPromParser([]byte(c.input))
var err error
for err == nil {
_, err = p.Next()
@ -314,11 +314,11 @@ func TestNullByteHandling(t *testing.T) {
}
const (
testdataSampleCount = 410
promtestdataSampleCount = 410
)
func BenchmarkParse(b *testing.B) {
for _, fn := range []string{"testdata.txt", "testdata.nometa.txt"} {
func BenchmarkPromParse(b *testing.B) {
for _, fn := range []string{"promtestdata.txt", "promtestdata.nometa.txt"} {
f, err := os.Open(fn)
require.NoError(b, err)
defer f.Close()
@ -329,12 +329,12 @@ func BenchmarkParse(b *testing.B) {
b.Run("no-decode-metric/"+fn, func(b *testing.B) {
total := 0
b.SetBytes(int64(len(buf) * (b.N / testdataSampleCount)))
b.SetBytes(int64(len(buf) * (b.N / promtestdataSampleCount)))
b.ReportAllocs()
b.ResetTimer()
for i := 0; i < b.N; i += testdataSampleCount {
p := New(buf)
for i := 0; i < b.N; i += promtestdataSampleCount {
p := NewPromParser(buf)
Outer:
for i < b.N {
@ -357,12 +357,12 @@ func BenchmarkParse(b *testing.B) {
b.Run("decode-metric/"+fn, func(b *testing.B) {
total := 0
b.SetBytes(int64(len(buf) * (b.N / testdataSampleCount)))
b.SetBytes(int64(len(buf) * (b.N / promtestdataSampleCount)))
b.ReportAllocs()
b.ResetTimer()
for i := 0; i < b.N; i += testdataSampleCount {
p := New(buf)
for i := 0; i < b.N; i += promtestdataSampleCount {
p := NewPromParser(buf)
Outer:
for i < b.N {
@ -390,12 +390,12 @@ func BenchmarkParse(b *testing.B) {
total := 0
res := make(labels.Labels, 0, 5)
b.SetBytes(int64(len(buf) * (b.N / testdataSampleCount)))
b.SetBytes(int64(len(buf) * (b.N / promtestdataSampleCount)))
b.ReportAllocs()
b.ResetTimer()
for i := 0; i < b.N; i += testdataSampleCount {
p := New(buf)
for i := 0; i < b.N; i += promtestdataSampleCount {
p := NewPromParser(buf)
Outer:
for i < b.N {
@ -420,13 +420,13 @@ func BenchmarkParse(b *testing.B) {
_ = total
})
b.Run("expfmt-text/"+fn, func(b *testing.B) {
b.SetBytes(int64(len(buf) * (b.N / testdataSampleCount)))
b.SetBytes(int64(len(buf) * (b.N / promtestdataSampleCount)))
b.ReportAllocs()
b.ResetTimer()
total := 0
for i := 0; i < b.N; i += testdataSampleCount {
for i := 0; i < b.N; i += promtestdataSampleCount {
var (
decSamples = make(model.Vector, 0, 50)
)
@ -450,7 +450,7 @@ func BenchmarkParse(b *testing.B) {
}
}
func BenchmarkGzip(b *testing.B) {
for _, fn := range []string{"testdata.txt", "testdata.nometa.txt"} {
for _, fn := range []string{"promtestdata.txt", "promtestdata.nometa.txt"} {
b.Run(fn, func(b *testing.B) {
f, err := os.Open(fn)
require.NoError(b, err)
@ -466,7 +466,7 @@ func BenchmarkGzip(b *testing.B) {
gbuf, err := ioutil.ReadAll(&buf)
require.NoError(b, err)
k := b.N / testdataSampleCount
k := b.N / promtestdataSampleCount
b.ReportAllocs()
b.SetBytes(int64(k) * int64(n))

0
pkg/textparse/testdata.nometa.txt → pkg/textparse/promtestdata.nometa.txt
View file

0
pkg/textparse/testdata.txt → pkg/textparse/promtestdata.txt
View file

33
scrape/scrape.go
View file

@ -434,7 +434,7 @@ func appender(app storage.Appender, limit int) storage.Appender {
// A scraper retrieves samples and accepts a status report at the end.
type scraper interface {
scrape(ctx context.Context, w io.Writer) error
scrape(ctx context.Context, w io.Writer) (string, error)
report(start time.Time, dur time.Duration, err error)
offset(interval time.Duration) time.Duration
}
@ -455,11 +455,11 @@ const acceptHeader = `text/plain;version=0.0.4;q=1,*/*;q=0.1`
var userAgentHeader = fmt.Sprintf("Prometheus/%s", version.Version)
func (s *targetScraper) scrape(ctx context.Context, w io.Writer) error {
func (s *targetScraper) scrape(ctx context.Context, w io.Writer) (string, error) {
if s.req == nil {
req, err := http.NewRequest("GET", s.URL().String(), nil)
if err != nil {
return err
return "", err
}
req.Header.Add("Accept", acceptHeader)
req.Header.Add("Accept-Encoding", "gzip")
@ -471,35 +471,38 @@ func (s *targetScraper) scrape(ctx context.Context, w io.Writer) error {
resp, err := ctxhttp.Do(ctx, s.client, s.req)
if err != nil {
return err
return "", err
}
defer resp.Body.Close()
if resp.StatusCode != http.StatusOK {
return fmt.Errorf("server returned HTTP status %s", resp.Status)
return "", fmt.Errorf("server returned HTTP status %s", resp.Status)
}
if resp.Header.Get("Content-Encoding") != "gzip" {
_, err = io.Copy(w, resp.Body)
return err
return "", err
}
if s.gzipr == nil {
s.buf = bufio.NewReader(resp.Body)
s.gzipr, err = gzip.NewReader(s.buf)
if err != nil {
return err
return "", err
}
} else {
s.buf.Reset(resp.Body)
if err = s.gzipr.Reset(s.buf); err != nil {
return err
return "", err
}
}
_, err = io.Copy(w, s.gzipr)
s.gzipr.Close()
return err
if err != nil {
return "", err
}
return resp.Header.Get("Content-Type"), nil
}
// A loop can run and be stopped again. It must not be reused after it was stopped.
@ -789,7 +792,7 @@ mainLoop:
b := sl.buffers.Get(sl.lastScrapeSize).([]byte)
buf := bytes.NewBuffer(b)
scrapeErr := sl.scraper.scrape(scrapeCtx, buf)
contentType, scrapeErr := sl.scraper.scrape(scrapeCtx, buf)
cancel()
if scrapeErr == nil {
@ -809,12 +812,12 @@ mainLoop:
// A failed scrape is the same as an empty scrape,
// we still call sl.append to trigger stale markers.
total, added, appErr := sl.append(b, start)
total, added, appErr := sl.append(b, contentType, start)
if appErr != nil {
level.Warn(sl.l).Log("msg", "append failed", "err", appErr)
// The append failed, probably due to a parse error or sample limit.
// Call sl.append again with an empty scrape to trigger stale markers.
if _, _, err := sl.append([]byte{}, start); err != nil {
if _, _, err := sl.append([]byte{}, "", start); err != nil {
level.Warn(sl.l).Log("msg", "append failed", "err", err)
}
}
@ -885,7 +888,7 @@ func (sl *scrapeLoop) endOfRunStaleness(last time.Time, ticker *time.Ticker, int
// Call sl.append again with an empty scrape to trigger stale markers.
// If the target has since been recreated and scraped, the
// stale markers will be out of order and ignored.
if _, _, err := sl.append([]byte{}, staleTime); err != nil {
if _, _, err := sl.append([]byte{}, "", staleTime); err != nil {
level.Error(sl.l).Log("msg", "stale append failed", "err", err)
}
if err := sl.reportStale(staleTime); err != nil {
@ -921,10 +924,10 @@ func (s samples) Less(i, j int) bool {
return s[i].t < s[j].t
}
func (sl *scrapeLoop) append(b []byte, ts time.Time) (total, added int, err error) {
func (sl *scrapeLoop) append(b []byte, contentType string, ts time.Time) (total, added int, err error) {
var (
app = sl.appender()
p = textparse.New(b)
p = textparse.New(b, contentType)
defTime = timestamp.FromTime(ts)
numOutOfOrder = 0
numDuplicates = 0

34
scrape/scrape_test.go
View file

@ -621,7 +621,7 @@ func TestScrapeLoopMetadata(t *testing.T) {
# other comment
test_metric 1
# TYPE test_metric_no_help gauge
# HELP test_metric_no_type other help text`), time.Now())
# HELP test_metric_no_type other help text`), "", time.Now())
testutil.Ok(t, err)
testutil.Equals(t, 1, total)
@ -824,7 +824,7 @@ func TestScrapeLoopAppend(t *testing.T) {
now := time.Now()
_, _, err := sl.append([]byte(test.scrapeLabels), now)
_, _, err := sl.append([]byte(test.scrapeLabels), "", now)
if err != nil {
t.Fatalf("Unexpected append error: %s", err)
}
@ -870,7 +870,7 @@ func TestScrapeLoopAppendSampleLimit(t *testing.T) {
beforeMetricValue := beforeMetric.GetCounter().GetValue()
now := time.Now()
_, _, err = sl.append([]byte("metric_a 1\nmetric_b 1\nmetric_c 1\n"), now)
_, _, err = sl.append([]byte("metric_a 1\nmetric_b 1\nmetric_c 1\n"), "", now)
if err != errSampleLimit {
t.Fatalf("Did not see expected sample limit error: %s", err)
}
@ -922,11 +922,11 @@ func TestScrapeLoop_ChangingMetricString(t *testing.T) {
)
now := time.Now()
_, _, err = sl.append([]byte(`metric_a{a="1",b="1"} 1`), now)
_, _, err = sl.append([]byte(`metric_a{a="1",b="1"} 1`), "", now)
if err != nil {
t.Fatalf("Unexpected append error: %s", err)
}
_, _, err = sl.append([]byte(`metric_a{b="1",a="1"} 2`), now.Add(time.Minute))
_, _, err = sl.append([]byte(`metric_a{b="1",a="1"} 2`), "", now.Add(time.Minute))
if err != nil {
t.Fatalf("Unexpected append error: %s", err)
}
@ -961,11 +961,11 @@ func TestScrapeLoopAppendStaleness(t *testing.T) {
)
now := time.Now()
_, _, err := sl.append([]byte("metric_a 1\n"), now)
_, _, err := sl.append([]byte("metric_a 1\n"), "", now)
if err != nil {
t.Fatalf("Unexpected append error: %s", err)
}
_, _, err = sl.append([]byte(""), now.Add(time.Second))
_, _, err = sl.append([]byte(""), "", now.Add(time.Second))
if err != nil {
t.Fatalf("Unexpected append error: %s", err)
}
@ -1006,11 +1006,11 @@ func TestScrapeLoopAppendNoStalenessIfTimestamp(t *testing.T) {
)
now := time.Now()
_, _, err := sl.append([]byte("metric_a 1 1000\n"), now)
_, _, err := sl.append([]byte("metric_a 1 1000\n"), "", now)
if err != nil {
t.Fatalf("Unexpected append error: %s", err)
}
_, _, err = sl.append([]byte(""), now.Add(time.Second))
_, _, err = sl.append([]byte(""), "", now.Add(time.Second))
if err != nil {
t.Fatalf("Unexpected append error: %s", err)
}
@ -1120,7 +1120,7 @@ func TestScrapeLoopAppendGracefullyIfAmendOrOutOfOrderOrOutOfBounds(t *testing.T
)
now := time.Unix(1, 0)
_, _, err := sl.append([]byte("out_of_order 1\namend 1\nnormal 1\nout_of_bounds 1\n"), now)
_, _, err := sl.append([]byte("out_of_order 1\namend 1\nnormal 1\nout_of_bounds 1\n"), "", now)
if err != nil {
t.Fatalf("Unexpected append error: %s", err)
}
@ -1153,7 +1153,7 @@ func TestScrapeLoopOutOfBoundsTimeError(t *testing.T) {
)
now := time.Now().Add(20 * time.Minute)
total, added, err := sl.append([]byte("normal 1\n"), now)
total, added, err := sl.append([]byte("normal 1\n"), "", now)
if total != 1 {
t.Error("expected 1 metric")
return
@ -1209,7 +1209,7 @@ func TestTargetScraperScrapeOK(t *testing.T) {
}
var buf bytes.Buffer
if err := ts.scrape(context.Background(), &buf); err != nil {
if _, err := ts.scrape(context.Background(), &buf); err != nil {
t.Fatalf("Unexpected scrape error: %s", err)
}
require.Equal(t, "metric_a 1\nmetric_b 2\n", buf.String())
@ -1249,7 +1249,7 @@ func TestTargetScrapeScrapeCancel(t *testing.T) {
}()
go func() {
if err := ts.scrape(ctx, ioutil.Discard); err != context.Canceled {
if _, err := ts.scrape(ctx, ioutil.Discard); err != context.Canceled {
errc <- fmt.Errorf("Expected context cancelation error but got: %s", err)
}
close(errc)
@ -1291,7 +1291,7 @@ func TestTargetScrapeScrapeNotFound(t *testing.T) {
client: http.DefaultClient,
}
if err := ts.scrape(context.Background(), ioutil.Discard); !strings.Contains(err.Error(), "404") {
if _, err := ts.scrape(context.Background(), ioutil.Discard); !strings.Contains(err.Error(), "404") {
t.Fatalf("Expected \"404 NotFound\" error but got: %s", err)
}
}
@ -1319,9 +1319,9 @@ func (ts *testScraper) report(start time.Time, duration time.Duration, err error
ts.lastError = err
}
func (ts *testScraper) scrape(ctx context.Context, w io.Writer) error {
func (ts *testScraper) scrape(ctx context.Context, w io.Writer) (string, error) {
if ts.scrapeFunc != nil {
return ts.scrapeFunc(ctx, w)
return "", ts.scrapeFunc(ctx, w)
}
return ts.scrapeErr
return "", ts.scrapeErr
}