Switch to common/expfmt for extraction

retrieval/target.go

@@ -18,6 +18,7 @@ import (
 	"crypto/x509"
 	"errors"
 	"fmt"
+	"io"
 	"io/ioutil"
 	"math/rand"
 	"net/http"
@@ -26,11 +27,10 @@ import (
 	"sync"
 	"time"
 
-	"github.com/prometheus/client_golang/extraction"
 	"github.com/prometheus/client_golang/prometheus"
-	"github.com/prometheus/log"
-
+	"github.com/prometheus/common/expfmt"
 	"github.com/prometheus/common/model"
+	"github.com/prometheus/log"
 
 	"github.com/prometheus/prometheus/config"
 	"github.com/prometheus/prometheus/storage"
@@ -301,30 +301,6 @@ func (t *Target) String() string {
 	return t.url.Host
 }
 
-// Ingest implements an extraction.Ingester.
-func (t *Target) Ingest(s model.Samples) error {
-	t.RLock()
-	deadline := t.deadline
-	t.RUnlock()
-	// Since the regular case is that ingestedSamples is ready to receive,
-	// first try without setting a timeout so that we don't need to allocate
-	// a timer most of the time.
-	select {
-	case t.ingestedSamples <- s:
-		return nil
-	default:
-		select {
-		case t.ingestedSamples <- s:
-			return nil
-		case <-time.After(deadline / 10):
-			return errIngestChannelFull
-		}
-	}
-}
-
-// Ensure that Target implements extraction.Ingester at compile time.
-var _ extraction.Ingester = (*Target)(nil)
-
 // RunScraper implements Target.
 func (t *Target) RunScraper(sampleAppender storage.SampleAppender) {
 	defer close(t.scraperStopped)
@@ -416,7 +392,7 @@ func (t *Target) scrape(sampleAppender storage.SampleAppender) (err error) {
 
 	defer func() {
 		t.status.setLastError(err)
-		recordScrapeHealth(sampleAppender, model.TimeFromTime(start), baseLabels, t.status.Health(), time.Since(start))
+		recordScrapeHealth(sampleAppender, start, baseLabels, t.status.Health(), time.Since(start))
 	}()
 
 	req, err := http.NewRequest("GET", t.URL().String(), nil)
@@ -429,27 +405,30 @@ func (t *Target) scrape(sampleAppender storage.SampleAppender) (err error) {
 	if err != nil {
 		return err
 	}
-	defer resp.Body.Close()
 	if resp.StatusCode != http.StatusOK {
 		return fmt.Errorf("server returned HTTP status %s", resp.Status)
 	}
 
-	processor, err := extraction.ProcessorForRequestHeader(resp.Header)
+	dec, err := expfmt.NewDecoder(resp.Body, resp.Header)
 	if err != nil {
 		return err
 	}
+	defer resp.Body.Close()
 
-	t.ingestedSamples = make(chan model.Samples, ingestedSamplesCap)
-
-	processOptions := &extraction.ProcessOptions{
-		Timestamp: model.TimeFromTime(start),
+	sdec := expfmt.SampleDecoder{
+		Dec: dec,
+		Opts: &expfmt.DecodeOptions{
+			Timestamp: model.TimeFromUnixNano(start.UnixNano()),
+		},
+	}
+
+	var samples model.Vector
+
+	for {
+		if err = sdec.Decode(&samples); err != nil {
+			break
 		}
-	go func() {
-		err = processor.ProcessSingle(resp.Body, t, processOptions)
-		close(t.ingestedSamples)
-	}()
 
-	for samples := range t.ingestedSamples {
 		for _, s := range samples {
 			if honorLabels {
 				// Merge the metric with the baseLabels for labels not already set in the
@@ -485,6 +464,10 @@ func (t *Target) scrape(sampleAppender storage.SampleAppender) (err error) {
 			sampleAppender.Append(s)
 		}
 	}
+
+	if err == io.EOF {
+		return nil
+	}
 	return err
 }
 
@@ -540,7 +523,7 @@ func (t *Target) MetaLabels() model.LabelSet {
 
 func recordScrapeHealth(
 	sampleAppender storage.SampleAppender,
-	timestamp model.Time,
+	timestamp time.Time,
 	baseLabels model.LabelSet,
 	health TargetHealth,
 	scrapeDuration time.Duration,
@@ -561,14 +544,16 @@ func recordScrapeHealth(
 		healthValue = model.SampleValue(1)
 	}
 
+	ts := model.TimeFromUnixNano(timestamp.UnixNano())
+
 	healthSample := &model.Sample{
 		Metric:    healthMetric,
-		Timestamp: timestamp,
+		Timestamp: ts,
 		Value:     healthValue,
 	}
 	durationSample := &model.Sample{
 		Metric:    durationMetric,
-		Timestamp: timestamp,
+		Timestamp: ts,
 		Value:     model.SampleValue(float64(scrapeDuration) / float64(time.Second)),
 	}