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pkg/crow/crow.go

@@ -21,10 +21,10 @@ import (
 
 // Config for the Crow metrics checker.
 type Config struct {
-	PrometheusAddr  string // Base URL of Prometheus server
-	GenerateSamples int    // Number of samples to generate
-	UserID          string // User ID to use when querying.
-	ExtraSelectors  string // Extra selectors for queries, i.e., cluster="prod"
+	PrometheusAddr string // Base URL of Prometheus server
+	NumSamples     int    // Number of samples to generate
+	UserID         string // User ID to use when querying.
+	ExtraSelectors string // Extra selectors for queries, i.e., cluster="prod"
 
 	// Querying Params
 
@@ -42,13 +42,13 @@ type Config struct {
 // RegisterFlags registers flags for the config to the given FlagSet.
 func (c *Config) RegisterFlags(f *flag.FlagSet) {
 	f.StringVar(&c.PrometheusAddr, "prometheus-addr", DefaultConfig.PrometheusAddr, "Root URL of the Prometheus API to query against")
-	f.IntVar(&c.GenerateSamples, "generate-samples", DefaultConfig.GenerateSamples, "Number of samples to generate when being scraped")
+	f.IntVar(&c.NumSamples, "generate-samples", DefaultConfig.NumSamples, "Number of samples to generate when being scraped")
 	f.StringVar(&c.UserID, "user-id", DefaultConfig.UserID, "UserID to attach to query. Useful for querying multi-tenated Cortex.")
 	f.StringVar(&c.ExtraSelectors, "extra-selectors", DefaultConfig.ExtraSelectors, "Extra selectors to include in queries, useful for identifying different instances of this job.")
 
-	f.DurationVar(&c.QueryDuration, "query-timeout", DefaultConfig.QueryTimeout, "timeout for querying")
+	f.DurationVar(&c.QueryTimeout, "query-timeout", DefaultConfig.QueryTimeout, "timeout for querying")
 	f.DurationVar(&c.QueryDuration, "query-duration", DefaultConfig.QueryDuration, "time before and after sample to search")
-	f.DurationVar(&c.QueryDuration, "query-step", DefaultConfig.QueryStep, "step between samples when searching")
+	f.DurationVar(&c.QueryStep, "query-step", DefaultConfig.QueryStep, "step between samples when searching")
 
 	f.IntVar(&c.MaxValidations, "max-validations", DefaultConfig.MaxValidations, "Maximum number of times to try validating a sample")
 	f.DurationVar(&c.MaxTimestampDelta, "max-timestamp-delta", DefaultConfig.MaxTimestampDelta, "maximum difference from the stored timestamp from the validating sample to allow")
@@ -57,8 +57,8 @@ func (c *Config) RegisterFlags(f *flag.FlagSet) {
 
 // DefaultConfig holds defaults for Crow settings.
 var DefaultConfig = Config{
-	MaxValidations:  5,
-	GenerateSamples: 10,
+	MaxValidations: 5,
+	NumSamples:     10,
 
 	QueryTimeout:  150 * time.Millisecond,
 	QueryDuration: 2 * time.Second,
@@ -291,7 +291,7 @@ func (c *Crow) validateInMatrix(b *sample, m model.Matrix) error {
 // schedule a validation job.
 func (c *Crow) TestMetrics() prometheus.Collector {
 	return &sampleGenerator{
-		numSamples: c.cfg.GenerateSamples,
+		numSamples: c.cfg.NumSamples,
 		sendCh:     c.sampleCh,
 
 		r: rand.New(rand.NewSource(time.Now().Unix())),

pkg/crow/crow_e2e_test.go

@@ -73,7 +73,7 @@ prometheus:
 
 	crowCfg := DefaultConfig
 	crowCfg.PrometheusAddr = "http://" + promAddr
-	crowCfg.GenerateSamples = 1
+	crowCfg.NumSamples = 1
 	crowCfg.ExtraSelectors = `cluster="test"`
 	crowCfg.UserID = "user"
 

pkg/crow/samples.go

@@ -54,6 +54,8 @@ func (sg *sampleGenerator) Collect(ch chan<- prometheus.Metric) {
 		)
 	)
 
+	usedLabels := map[string]struct{}{}
+
 	samples := make([]*sample, sg.numSamples)
 	for s := 0; s < sg.numSamples; s++ {
 		samples[s] = &sample{
@@ -62,10 +64,19 @@ func (sg *sampleGenerator) Collect(ch chan<- prometheus.Metric) {
 			Value:      float64(sg.r.Int63n(1_000_000)),
 		}
 
+	GenLabel:
+		labelSuffix := make([]byte, 2)
+		_, _ = sg.r.Read(labelSuffix)
+		label := fmt.Sprintf("sample_%x", labelSuffix)
+		if _, exist := usedLabels[label]; exist {
+			goto GenLabel
+		}
+		usedLabels[label] = struct{}{}
+
 		ch <- prometheus.MustNewConstMetric(
 			desc,
 			prometheus.GaugeValue,
-			samples[s].Value, fmt.Sprintf("sample_%d", s),
+			samples[s].Value, label,
 		)
 	}
 

pkg/crow/samples_test.go

@@ -86,16 +86,16 @@ func Test_sampleGenerator(t *testing.T) {
 
 	expect := `# HELP crow_validation_sample Sample to validate
 # TYPE crow_validation_sample gauge
-crow_validation_sample{sample_num="sample_0"} 165505
-crow_validation_sample{sample_num="sample_1"} 393152
-crow_validation_sample{sample_num="sample_2"} 995827
-crow_validation_sample{sample_num="sample_3"} 197794
-crow_validation_sample{sample_num="sample_4"} 376202
-crow_validation_sample{sample_num="sample_5"} 126063
-crow_validation_sample{sample_num="sample_6"} 980153
-crow_validation_sample{sample_num="sample_7"} 422456
-crow_validation_sample{sample_num="sample_8"} 894929
-crow_validation_sample{sample_num="sample_9"} 637646
+crow_validation_sample{sample_num="sample_1204"} 197794
+crow_validation_sample{sample_num="sample_48a7"} 980153
+crow_validation_sample{sample_num="sample_5baf"} 376202
+crow_validation_sample{sample_num="sample_9ee0"} 422456
+crow_validation_sample{sample_num="sample_b10d"} 894929
+crow_validation_sample{sample_num="sample_b44c"} 976708
+crow_validation_sample{sample_num="sample_c041"} 165505
+crow_validation_sample{sample_num="sample_d3ff"} 995827
+crow_validation_sample{sample_num="sample_e85f"} 259259
+crow_validation_sample{sample_num="sample_f8f9"} 637646
 `
 	require.Equal(t, expect, sb.String())
 }