metrics: make resettingtimer not expose internal values

metrics/exp/exp.go

@@ -177,7 +177,7 @@ func (exp *exp) publishTimer(name string, metric metrics.Timer) {
 func (exp *exp) publishResettingTimer(name string, metric metrics.ResettingTimer) {
 	t := metric.Snapshot()
 	ps := t.Percentiles([]float64{50, 75, 95, 99})
-	exp.getInt(name + ".count").Set(int64(len(t.Values())))
+	exp.getInt(name + ".count").Set(int64(t.Count()))
 	exp.getFloat(name + ".mean").Set(t.Mean())
 	exp.getInt(name + ".50-percentile").Set(ps[0])
 	exp.getInt(name + ".75-percentile").Set(ps[1])

metrics/influxdb/influxdb.go

@@ -99,17 +99,16 @@ func readMeter(namespace, name string, i interface{}) (string, map[string]interf
 		return measurement, fields
 	case metrics.ResettingTimer:
 		t := metric.Snapshot()
-		if len(t.Values()) == 0 {
+		if t.Count() == 0 {
 			break
 		}
 		ps := t.Percentiles([]float64{50, 95, 99})
-		val := t.Values()
 		measurement := fmt.Sprintf("%s%s.span", namespace, name)
 		fields := map[string]interface{}{
-			"count": len(val),
-			"max":   val[len(val)-1],
+			"count": t.Count(),
+			"max":   t.Max(),
 			"mean":  t.Mean(),
-			"min":   val[0],
+			"min":   t.Min(),
 			"p50":   ps[0],
 			"p95":   ps[1],
 			"p99":   ps[2],

metrics/prometheus/collector.go

@@ -122,12 +122,11 @@ func (c *collector) addTimer(name string, m metrics.TimerSnapshot) {
 }
 
 func (c *collector) addResettingTimer(name string, m metrics.ResettingTimerSnapshot) {
-	if len(m.Values()) <= 0 {
+	if m.Count() <= 0 {
 		return
 	}
 	ps := m.Percentiles([]float64{50, 95, 99})
-	val := m.Values()
-	c.writeSummaryCounter(name, len(val))
+	c.writeSummaryCounter(name, m.Count())
 	c.buff.WriteString(fmt.Sprintf(typeSummaryTpl, mutateKey(name)))
 	c.writeSummaryPercentile(name, "0.50", ps[0])
 	c.writeSummaryPercentile(name, "0.95", ps[1])

metrics/resetting_timer.go

@@ -12,8 +12,10 @@ import (
 const InitialResettingTimerSliceCap = 10
 
 type ResettingTimerSnapshot interface {
-	Values() []int64
+	Count() int
 	Mean() float64
+	Max() int64
+	Min() int64
 	Percentiles([]float64) []int64
 }
 
@@ -63,7 +65,10 @@ func (NilResettingTimer) Time(f func())                      { f() }
 func (NilResettingTimer) Update(time.Duration)               {}
 func (NilResettingTimer) Percentiles([]float64) []int64      { return nil }
 func (NilResettingTimer) Mean() float64                      { return 0.0 }
+func (NilResettingTimer) Max() int64                         { return 0 }
+func (NilResettingTimer) Min() int64                         { return 0 }
 func (NilResettingTimer) UpdateSince(time.Time)              {}
+func (NilResettingTimer) Count() int                         { return 0 }
 
 // StandardResettingTimer is the standard implementation of a ResettingTimer.
 // and Meter.
@@ -72,11 +77,6 @@ type StandardResettingTimer struct {
 	mutex  sync.Mutex
 }
 
-//// Values returns a slice with all measurements.
-//func (t *StandardResettingTimer) Values() []int64 {
-//	return t.values
-//}
-
 // Snapshot resets the timer and returns a read-only copy of its contents.
 func (t *StandardResettingTimer) Snapshot() ResettingTimerSnapshot {
 	t.mutex.Lock()
@@ -114,13 +114,15 @@ func (t *StandardResettingTimer) UpdateSince(ts time.Time) {
 type resettingTimerSnapshot struct {
 	values              []int64
 	mean                float64
+	max                 int64
+	min                 int64
 	thresholdBoundaries []int64
 	calculated          bool
 }
 
-// Values returns all values from snapshot.
-func (t *resettingTimerSnapshot) Values() []int64 {
-	return t.values
+// Count return the length of the values from snapshot.
+func (t *resettingTimerSnapshot) Count() int {
+	return len(t.values)
 }
 
 // Percentiles returns the boundaries for the input percentiles.
@@ -134,12 +136,32 @@ func (t *resettingTimerSnapshot) Percentiles(percentiles []float64) []int64 {
 // note: this method is not thread safe
 func (t *resettingTimerSnapshot) Mean() float64 {
 	if !t.calculated {
-		t.calc([]float64{})
+		t.calc(nil)
 	}
 
 	return t.mean
 }
 
+// Max returns the max of the snapshotted values
+// note: this method is not thread safe
+func (t *resettingTimerSnapshot) Max() int64 {
+	if !t.calculated {
+		t.calc(nil)
+	}
+
+	return t.max
+}
+
+// Min returns the min of the snapshotted values
+// note: this method is not thread safe
+func (t *resettingTimerSnapshot) Min() int64 {
+	if !t.calculated {
+		t.calc(nil)
+	}
+
+	return t.min
+}
+
 func (t *resettingTimerSnapshot) calc(percentiles []float64) {
 	slices.Sort(t.values)
 	count := len(t.values)
@@ -149,18 +171,18 @@ func (t *resettingTimerSnapshot) calc(percentiles []float64) {
 		t.calculated = true
 		return
 	}
-	min := t.values[0]
-	max := t.values[count-1]
+	t.min = t.values[0]
+	t.max = t.values[count-1]
 
 	cumulativeValues := make([]int64, count)
-	cumulativeValues[0] = min
+	cumulativeValues[0] = t.min
 	for i := 1; i < count; i++ {
 		cumulativeValues[i] = t.values[i] + cumulativeValues[i-1]
 	}
 
 	t.thresholdBoundaries = make([]int64, len(percentiles))
 
-	thresholdBoundary := max
+	thresholdBoundary := t.max
 
 	for i, pct := range percentiles {
 		if count > 1 {

metrics/resetting_timer_test.go

@@ -75,16 +75,12 @@ func TestResettingTimer(t *testing.T) {
 
 		ps := snap.Percentiles([]float64{50, 95, 99})
 
-		val := snap.Values()
+		if tt.wantMin != snap.Min() {
+			t.Fatalf("%d: min: got %d, want %d", ind, snap.Min(), tt.wantMin)
+		}
 
-		if len(val) > 0 {
-			if tt.wantMin != val[0] {
-				t.Fatalf("%d: min: got %d, want %d", ind, val[0], tt.wantMin)
-			}
-
-			if tt.wantMax != val[len(val)-1] {
-				t.Fatalf("%d: max: got %d, want %d", ind, val[len(val)-1], tt.wantMax)
-			}
+		if tt.wantMax != snap.Max() {
+			t.Fatalf("%d: max: got %d, want %d", ind, snap.Max(), tt.wantMax)
 		}
 
 		if tt.wantMean != snap.Mean() {
@@ -177,16 +173,12 @@ func TestResettingTimerWithFivePercentiles(t *testing.T) {
 
 		ps := snap.Percentiles([]float64{5, 20, 50, 95, 99})
 
-		val := snap.Values()
+		if tt.wantMin != snap.Min() {
+			t.Fatalf("%d: min: got %d, want %d", ind, snap.Min(), tt.wantMin)
+		}
 
-		if len(val) > 0 {
-			if tt.wantMin != val[0] {
-				t.Fatalf("%d: min: got %d, want %d", ind, val[0], tt.wantMin)
-			}
-
-			if tt.wantMax != val[len(val)-1] {
-				t.Fatalf("%d: max: got %d, want %d", ind, val[len(val)-1], tt.wantMax)
-			}
+		if tt.wantMax != snap.Max() {
+			t.Fatalf("%d: max: got %d, want %d", ind, snap.Max(), tt.wantMax)
 		}
 
 		if tt.wantMean != snap.Mean() {