Add support for optionally missing +Inf bucket in protobuf.

Also, clean up style issues in metricfamilyprocessor.go.

extraction/metricfamilyprocessor.go

@@ -16,6 +16,7 @@ package extraction
 import (
 	"fmt"
 	"io"
+	"math"
 
 	dto "github.com/prometheus/client_model/go"
 
@@ -85,7 +86,10 @@ func extractCounter(out Ingester, o *ProcessOptions, f *dto.MetricFamily) error
 			continue
 		}
 
-		sample := new(model.Sample)
+		sample := &model.Sample{
+			Metric: model.Metric{},
+			Value:  model.SampleValue(m.Counter.GetValue()),
+		}
 		samples = append(samples, sample)
 
 		if m.TimestampMs != nil {
@@ -93,16 +97,12 @@ func extractCounter(out Ingester, o *ProcessOptions, f *dto.MetricFamily) error
 		} else {
 			sample.Timestamp = o.Timestamp
 		}
-		sample.Metric = model.Metric{}
-		metric := sample.Metric
 
+		metric := sample.Metric
 		for _, p := range m.Label {
 			metric[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
 		}
-
 		metric[model.MetricNameLabel] = model.LabelValue(f.GetName())
-
-		sample.Value = model.SampleValue(m.Counter.GetValue())
 	}
 
 	return out.Ingest(samples)
@@ -116,7 +116,10 @@ func extractGauge(out Ingester, o *ProcessOptions, f *dto.MetricFamily) error {
 			continue
 		}
 
-		sample := new(model.Sample)
+		sample := &model.Sample{
+			Metric: model.Metric{},
+			Value:  model.SampleValue(m.Gauge.GetValue()),
+		}
 		samples = append(samples, sample)
 
 		if m.TimestampMs != nil {
@@ -124,16 +127,12 @@ func extractGauge(out Ingester, o *ProcessOptions, f *dto.MetricFamily) error {
 		} else {
 			sample.Timestamp = o.Timestamp
 		}
-		sample.Metric = model.Metric{}
-		metric := sample.Metric
 
+		metric := sample.Metric
 		for _, p := range m.Label {
 			metric[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
 		}
-
 		metric[model.MetricNameLabel] = model.LabelValue(f.GetName())
-
-		sample.Value = model.SampleValue(m.Gauge.GetValue())
 	}
 
 	return out.Ingest(samples)
@@ -153,48 +152,50 @@ func extractSummary(out Ingester, o *ProcessOptions, f *dto.MetricFamily) error
 		}
 
 		for _, q := range m.Summary.Quantile {
-			sample := new(model.Sample)
+			sample := &model.Sample{
+				Metric:    model.Metric{},
+				Value:     model.SampleValue(q.GetValue()),
+				Timestamp: timestamp,
+			}
 			samples = append(samples, sample)
 
-			sample.Timestamp = timestamp
-			sample.Metric = model.Metric{}
 			metric := sample.Metric
-
 			for _, p := range m.Label {
 				metric[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
 			}
 			// BUG(matt): Update other names to "quantile".
 			metric[model.LabelName("quantile")] = model.LabelValue(fmt.Sprint(q.GetQuantile()))
-
 			metric[model.MetricNameLabel] = model.LabelValue(f.GetName())
-
-			sample.Value = model.SampleValue(q.GetValue())
 		}
 
 		if m.Summary.SampleSum != nil {
-			sum := new(model.Sample)
+			sum := &model.Sample{
-			sum.Timestamp = timestamp
+				Metric:    model.Metric{},
-			metric := model.Metric{}
+				Value:     model.SampleValue(m.Summary.GetSampleSum()),
+				Timestamp: timestamp,
+			}
+			samples = append(samples, sum)
+
+			metric := sum.Metric
 			for _, p := range m.Label {
 				metric[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
 			}
 			metric[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_sum")
-			sum.Metric = metric
-			sum.Value = model.SampleValue(m.Summary.GetSampleSum())
-			samples = append(samples, sum)
 		}
 
 		if m.Summary.SampleCount != nil {
-			count := new(model.Sample)
+			count := &model.Sample{
-			count.Timestamp = timestamp
+				Metric:    model.Metric{},
-			metric := model.Metric{}
+				Value:     model.SampleValue(m.Summary.GetSampleCount()),
+				Timestamp: timestamp,
+			}
+			samples = append(samples, count)
+
+			metric := count.Metric
 			for _, p := range m.Label {
 				metric[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
 			}
 			metric[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_count")
-			count.Metric = metric
-			count.Value = model.SampleValue(m.Summary.GetSampleCount())
-			samples = append(samples, count)
 		}
 	}
 
@@ -209,7 +210,10 @@ func extractUntyped(out Ingester, o *ProcessOptions, f *dto.MetricFamily) error
 			continue
 		}
 
-		sample := new(model.Sample)
+		sample := &model.Sample{
+			Metric: model.Metric{},
+			Value:  model.SampleValue(m.Untyped.GetValue()),
+		}
 		samples = append(samples, sample)
 
 		if m.TimestampMs != nil {
@@ -217,16 +221,12 @@ func extractUntyped(out Ingester, o *ProcessOptions, f *dto.MetricFamily) error
 		} else {
 			sample.Timestamp = o.Timestamp
 		}
-		sample.Metric = model.Metric{}
-		metric := sample.Metric
 
+		metric := sample.Metric
 		for _, p := range m.Label {
 			metric[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
 		}
-
 		metric[model.MetricNameLabel] = model.LabelValue(f.GetName())
-
-		sample.Value = model.SampleValue(m.Untyped.GetValue())
 	}
 
 	return out.Ingest(samples)
@@ -245,49 +245,72 @@ func extractHistogram(out Ingester, o *ProcessOptions, f *dto.MetricFamily) erro
 			timestamp = model.TimestampFromUnixNano(*m.TimestampMs * 1000000)
 		}
 
+		infSeen := false
+
 		for _, q := range m.Histogram.Bucket {
-			sample := new(model.Sample)
+			sample := &model.Sample{
+				Metric:    model.Metric{},
+				Value:     model.SampleValue(q.GetCumulativeCount()),
+				Timestamp: timestamp,
+			}
 			samples = append(samples, sample)
 
-			sample.Timestamp = timestamp
-			sample.Metric = model.Metric{}
 			metric := sample.Metric
-
 			for _, p := range m.Label {
 				metric[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
 			}
 			metric[model.LabelName("le")] = model.LabelValue(fmt.Sprint(q.GetUpperBound()))
-
 			metric[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_bucket")
 
-			sample.Value = model.SampleValue(q.GetCumulativeCount())
+			if math.IsInf(q.GetUpperBound(), +1) {
+				infSeen = true
+			}
 		}
-		// TODO: If +Inf bucket is missing, add it.
 
 		if m.Histogram.SampleSum != nil {
-			sum := new(model.Sample)
+			sum := &model.Sample{
-			sum.Timestamp = timestamp
+				Metric:    model.Metric{},
-			metric := model.Metric{}
+				Value:     model.SampleValue(m.Histogram.GetSampleSum()),
+				Timestamp: timestamp,
+			}
+			samples = append(samples, sum)
+
+			metric := sum.Metric
 			for _, p := range m.Label {
 				metric[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
 			}
 			metric[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_sum")
-			sum.Metric = metric
-			sum.Value = model.SampleValue(m.Histogram.GetSampleSum())
-			samples = append(samples, sum)
 		}
 
 		if m.Histogram.SampleCount != nil {
-			count := new(model.Sample)
+			count := &model.Sample{
-			count.Timestamp = timestamp
+				Metric:    model.Metric{},
-			metric := model.Metric{}
+				Value:     model.SampleValue(m.Histogram.GetSampleCount()),
+				Timestamp: timestamp,
+			}
+			samples = append(samples, count)
+
+			metric := count.Metric
 			for _, p := range m.Label {
 				metric[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
 			}
 			metric[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_count")
-			count.Metric = metric
+
-			count.Value = model.SampleValue(m.Histogram.GetSampleCount())
+			if !infSeen {
-			samples = append(samples, count)
+				infBucket := &model.Sample{
+					Metric:    model.Metric{},
+					Value:     count.Value,
+					Timestamp: timestamp,
+				}
+				samples = append(samples, infBucket)
+
+				metric := infBucket.Metric
+				for _, p := range m.Label {
+					metric[model.LabelName(p.GetName())] = model.LabelValue(p.GetValue())
+				}
+				metric[model.LabelName("le")] = model.LabelValue("+Inf")
+				metric[model.MetricNameLabel] = model.LabelValue(f.GetName() + "_bucket")
+			}
 		}
 	}
 

text/create.go

@@ -24,6 +24,7 @@ import (
 	"bytes"
 	"fmt"
 	"io"
+	"math"
 	"strings"
 
 	dto "github.com/prometheus/client_model/go"
@@ -145,6 +146,7 @@ func MetricFamilyToText(out io.Writer, in *dto.MetricFamily) (int, error) {
 					"expected summary in metric %s", metric,
 				)
 			}
+			infSeen := false
 			for _, q := range metric.Histogram.Bucket {
 				n, err = writeSample(
 					name+"_bucket", metric,
@@ -156,7 +158,21 @@ func MetricFamilyToText(out io.Writer, in *dto.MetricFamily) (int, error) {
 				if err != nil {
 					return written, err
 				}
-                        // TODO: Add +inf bucket if it's missing.
+				if math.IsInf(q.GetUpperBound(), +1) {
+					infSeen = true
+				}
+			}
+			if !infSeen {
+				n, err = writeSample(
+					name+"_bucket", metric,
+					"le", "+Inf",
+					float64(metric.Histogram.GetSampleCount()),
+					out,
+				)
+				if err != nil {
+					return written, err
+				}
+				written += n
 			}
 			n, err = writeSample(
 				name+"_sum", metric, "", "",

text/create_test.go

@@ -267,6 +267,50 @@ request_duration_microseconds_bucket{le="172.8"} 1524
 request_duration_microseconds_bucket{le="+Inf"} 2693
 request_duration_microseconds_sum 1.7560473e+06
 request_duration_microseconds_count 2693
+`,
+		},
+		// 5: Histogram with missing +Inf bucket.
+		{
+			in: &dto.MetricFamily{
+				Name: proto.String("request_duration_microseconds"),
+				Help: proto.String("The response latency."),
+				Type: dto.MetricType_HISTOGRAM.Enum(),
+				Metric: []*dto.Metric{
+					&dto.Metric{
+						Histogram: &dto.Histogram{
+							SampleCount: proto.Uint64(2693),
+							SampleSum:   proto.Float64(1756047.3),
+							Bucket: []*dto.Bucket{
+								&dto.Bucket{
+									UpperBound:      proto.Float64(100),
+									CumulativeCount: proto.Uint64(123),
+								},
+								&dto.Bucket{
+									UpperBound:      proto.Float64(120),
+									CumulativeCount: proto.Uint64(412),
+								},
+								&dto.Bucket{
+									UpperBound:      proto.Float64(144),
+									CumulativeCount: proto.Uint64(592),
+								},
+								&dto.Bucket{
+									UpperBound:      proto.Float64(172.8),
+									CumulativeCount: proto.Uint64(1524),
+								},
+							},
+						},
+					},
+				},
+			},
+			out: `# HELP request_duration_microseconds The response latency.
+# TYPE request_duration_microseconds histogram
+request_duration_microseconds_bucket{le="100"} 123
+request_duration_microseconds_bucket{le="120"} 412
+request_duration_microseconds_bucket{le="144"} 592
+request_duration_microseconds_bucket{le="172.8"} 1524
+request_duration_microseconds_bucket{le="+Inf"} 2693
+request_duration_microseconds_sum 1.7560473e+06
+request_duration_microseconds_count 2693
 `,
 		},
 	}