Move appender construction from Target to scrapePool

retrieval/scrape.go

@@ -23,6 +23,7 @@ import (
 	"github.com/prometheus/common/model"
 	"golang.org/x/net/context"
 
+	"github.com/prometheus/prometheus/config"
 	"github.com/prometheus/prometheus/storage"
 	"github.com/prometheus/prometheus/storage/local"
 )
@@ -69,6 +70,7 @@ func init() {
 // scrapePool manages scrapes for sets of targets.
 type scrapePool struct {
 	appender storage.SampleAppender
+	config   *config.ScrapeConfig
 
 	ctx     context.Context
 	mtx     sync.RWMutex
@@ -77,9 +79,10 @@ type scrapePool struct {
 	targets map[model.Fingerprint]loop
 }
 
-func newScrapePool(app storage.SampleAppender) *scrapePool {
+func newScrapePool(cfg *config.ScrapeConfig, app storage.SampleAppender) *scrapePool {
 	return &scrapePool{
 		appender: app,
+		config:   cfg,
 		tgroups:  map[string]map[model.Fingerprint]*Target{},
 	}
 }
@@ -104,6 +107,40 @@ func (sp *scrapePool) stop() {
 	wg.Wait()
 }
 
+// sampleAppender returns an appender for ingested samples from the target.
+func (sp *scrapePool) sampleAppender(target *Target) storage.SampleAppender {
+	app := sp.appender
+	// The relabelAppender has to be inside the label-modifying appenders
+	// so the relabeling rules are applied to the correct label set.
+	if mrc := sp.config.MetricRelabelConfigs; len(mrc) > 0 {
+		app = relabelAppender{
+			SampleAppender: app,
+			relabelings:    mrc,
+		}
+	}
+
+	if sp.config.HonorLabels {
+		app = honorLabelsAppender{
+			SampleAppender: app,
+			labels:         target.Labels(),
+		}
+	} else {
+		app = ruleLabelsAppender{
+			SampleAppender: app,
+			labels:         target.Labels(),
+		}
+	}
+	return app
+}
+
+// reportAppender returns an appender for reporting samples for the target.
+func (sp *scrapePool) reportAppender(target *Target) storage.SampleAppender {
+	return ruleLabelsAppender{
+		SampleAppender: sp.appender,
+		labels:         target.Labels(),
+	}
+}
+
 func (sp *scrapePool) sync(tgroups map[string]map[model.Fingerprint]*Target) {
 	sp.mtx.Lock()
 
@@ -127,7 +164,7 @@ func (sp *scrapePool) sync(tgroups map[string]map[model.Fingerprint]*Target) {
 			} else {
 				newTargets[fp] = tnew
 
-				tnew.scrapeLoop = newScrapeLoop(sp.ctx, tnew, tnew.wrapAppender(sp.appender), tnew.wrapReportingAppender(sp.appender))
+				tnew.scrapeLoop = newScrapeLoop(sp.ctx, tnew, sp.sampleAppender(tnew), sp.reportAppender(tnew))
 				go tnew.scrapeLoop.run(tnew.interval(), tnew.timeout(), nil)
 			}
 		}

retrieval/scrape_test.go

@@ -20,9 +20,86 @@ import (
 	"github.com/prometheus/common/model"
 	"golang.org/x/net/context"
 
-	// "github.com/prometheus/prometheus/storage"
+	"github.com/prometheus/prometheus/config"
 )
 
+func TestScrapePoolReportAppender(t *testing.T) {
+	cfg := &config.ScrapeConfig{
+		MetricRelabelConfigs: []*config.RelabelConfig{
+			{}, {}, {},
+		},
+	}
+	target := newTestTarget("example.com:80", 10*time.Millisecond, nil)
+	app := &nopAppender{}
+
+	sp := newScrapePool(cfg, app)
+
+	cfg.HonorLabels = false
+	wrapped := sp.reportAppender(target)
+
+	rl, ok := wrapped.(ruleLabelsAppender)
+	if !ok {
+		t.Fatalf("Expected ruleLabelsAppender but got %T", wrapped)
+	}
+	if rl.SampleAppender != app {
+		t.Fatalf("Expected base appender but got %T", rl.SampleAppender)
+	}
+
+	cfg.HonorLabels = true
+	wrapped = sp.reportAppender(target)
+
+	hl, ok := wrapped.(ruleLabelsAppender)
+	if !ok {
+		t.Fatalf("Expected ruleLabelsAppender but got %T", wrapped)
+	}
+	if hl.SampleAppender != app {
+		t.Fatalf("Expected base appender but got %T", hl.SampleAppender)
+	}
+}
+
+func TestScrapePoolSampleAppender(t *testing.T) {
+	cfg := &config.ScrapeConfig{
+		MetricRelabelConfigs: []*config.RelabelConfig{
+			{}, {}, {},
+		},
+	}
+
+	target := newTestTarget("example.com:80", 10*time.Millisecond, nil)
+	app := &nopAppender{}
+
+	sp := newScrapePool(cfg, app)
+
+	cfg.HonorLabels = false
+	wrapped := sp.sampleAppender(target)
+
+	rl, ok := wrapped.(ruleLabelsAppender)
+	if !ok {
+		t.Fatalf("Expected ruleLabelsAppender but got %T", wrapped)
+	}
+	re, ok := rl.SampleAppender.(relabelAppender)
+	if !ok {
+		t.Fatalf("Expected relabelAppender but got %T", rl.SampleAppender)
+	}
+	if re.SampleAppender != app {
+		t.Fatalf("Expected base appender but got %T", re.SampleAppender)
+	}
+
+	cfg.HonorLabels = true
+	wrapped = sp.sampleAppender(target)
+
+	hl, ok := wrapped.(honorLabelsAppender)
+	if !ok {
+		t.Fatalf("Expected honorLabelsAppender but got %T", wrapped)
+	}
+	re, ok = hl.SampleAppender.(relabelAppender)
+	if !ok {
+		t.Fatalf("Expected relabelAppender but got %T", hl.SampleAppender)
+	}
+	if re.SampleAppender != app {
+		t.Fatalf("Expected base appender but got %T", re.SampleAppender)
+	}
+}
+
 func TestScrapeLoopRun(t *testing.T) {
 	var (
 		signal = make(chan struct{})

retrieval/target.go

@@ -121,13 +121,12 @@ type Target struct {
 	// The status object for the target. It is only set once on initialization.
 	status *TargetStatus
 
-	scrapeLoop *scrapeLoop
+	scrapeLoop   *scrapeLoop
+	scrapeConfig *config.ScrapeConfig
 
 	// Mutex protects the members below.
 	sync.RWMutex
 
-	scrapeConfig *config.ScrapeConfig
-
 	// Labels before any processing.
 	metaLabels model.LabelSet
 	// Any labels that are added to this target and its metrics.
@@ -265,42 +264,6 @@ func (t *Target) path() string {
 	return string(t.labels[model.MetricsPathLabel])
 }
 
-// wrapAppender wraps a SampleAppender for samples ingested from the target.
-// RLock must be acquired by the caller.
-func (t *Target) wrapAppender(app storage.SampleAppender) storage.SampleAppender {
-	// The relabelAppender has to be inside the label-modifying appenders
-	// so the relabeling rules are applied to the correct label set.
-	if mrc := t.scrapeConfig.MetricRelabelConfigs; len(mrc) > 0 {
-		app = relabelAppender{
-			SampleAppender: app,
-			relabelings:    mrc,
-		}
-	}
-
-	if t.scrapeConfig.HonorLabels {
-		app = honorLabelsAppender{
-			SampleAppender: app,
-			labels:         t.unlockedLabels(),
-		}
-	} else {
-		app = ruleLabelsAppender{
-			SampleAppender: app,
-			labels:         t.unlockedLabels(),
-		}
-	}
-	return app
-}
-
-// wrapReportingAppender wraps an appender for target status report samples.
-// It ignores any relabeling rules set for the target.
-// RLock must not be acquired by the caller.
-func (t *Target) wrapReportingAppender(app storage.SampleAppender) storage.SampleAppender {
-	return ruleLabelsAppender{
-		SampleAppender: app,
-		labels:         t.Labels(),
-	}
-}
-
 // URL returns a copy of the target's URL.
 func (t *Target) URL() *url.URL {
 	t.RLock()

retrieval/target_test.go

@@ -92,82 +92,6 @@ func TestTargetOffset(t *testing.T) {
 	}
 }
 
-func TestTargetWrapReportingAppender(t *testing.T) {
-	cfg := &config.ScrapeConfig{
-		MetricRelabelConfigs: []*config.RelabelConfig{
-			{}, {}, {},
-		},
-	}
-
-	target := newTestTarget("example.com:80", 10*time.Millisecond, nil)
-	target.scrapeConfig = cfg
-	app := &nopAppender{}
-
-	cfg.HonorLabels = false
-	wrapped := target.wrapReportingAppender(app)
-
-	rl, ok := wrapped.(ruleLabelsAppender)
-	if !ok {
-		t.Fatalf("Expected ruleLabelsAppender but got %T", wrapped)
-	}
-	if rl.SampleAppender != app {
-		t.Fatalf("Expected base appender but got %T", rl.SampleAppender)
-	}
-
-	cfg.HonorLabels = true
-	wrapped = target.wrapReportingAppender(app)
-
-	hl, ok := wrapped.(ruleLabelsAppender)
-	if !ok {
-		t.Fatalf("Expected ruleLabelsAppender but got %T", wrapped)
-	}
-	if hl.SampleAppender != app {
-		t.Fatalf("Expected base appender but got %T", hl.SampleAppender)
-	}
-}
-
-func TestTargetWrapAppender(t *testing.T) {
-	cfg := &config.ScrapeConfig{
-		MetricRelabelConfigs: []*config.RelabelConfig{
-			{}, {}, {},
-		},
-	}
-
-	target := newTestTarget("example.com:80", 10*time.Millisecond, nil)
-	target.scrapeConfig = cfg
-	app := &nopAppender{}
-
-	cfg.HonorLabels = false
-	wrapped := target.wrapAppender(app)
-
-	rl, ok := wrapped.(ruleLabelsAppender)
-	if !ok {
-		t.Fatalf("Expected ruleLabelsAppender but got %T", wrapped)
-	}
-	re, ok := rl.SampleAppender.(relabelAppender)
-	if !ok {
-		t.Fatalf("Expected relabelAppender but got %T", rl.SampleAppender)
-	}
-	if re.SampleAppender != app {
-		t.Fatalf("Expected base appender but got %T", re.SampleAppender)
-	}
-
-	cfg.HonorLabels = true
-	wrapped = target.wrapAppender(app)
-
-	hl, ok := wrapped.(honorLabelsAppender)
-	if !ok {
-		t.Fatalf("Expected honorLabelsAppender but got %T", wrapped)
-	}
-	re, ok = hl.SampleAppender.(relabelAppender)
-	if !ok {
-		t.Fatalf("Expected relabelAppender but got %T", hl.SampleAppender)
-	}
-	if re.SampleAppender != app {
-		t.Fatalf("Expected base appender but got %T", re.SampleAppender)
-	}
-}
-
 func TestTargetScrape404(t *testing.T) {
 	server := httptest.NewServer(
 		http.HandlerFunc(

retrieval/targetmanager.go

@@ -184,7 +184,7 @@ type targetSet struct {
 func newTargetSet(cfg *config.ScrapeConfig, app storage.SampleAppender) *targetSet {
 	ts := &targetSet{
 		tgroups:    map[string]map[model.Fingerprint]*Target{},
-		scrapePool: newScrapePool(app),
+		scrapePool: newScrapePool(cfg, app),
 		syncCh:     make(chan struct{}, 1),
 		config:     cfg,
 	}