prometheusremotewriteexporter: fix panic on histogram without buckets (…

…open-telemetry#12854)

exporter/prometheusremotewriteexporter/exporter_test.go

@@ -369,6 +369,8 @@ func Test_PushMetrics(t *testing.T) {
 
  histogramBatch := getMetricsFromMetricList(validMetrics1[validHistogram], validMetrics2[validHistogram])
 
+ emptyDataPointHistogramBatch := getMetricsFromMetricList(validMetrics1[validEmptyHistogram], validMetrics2[validEmptyHistogram])
+
  summaryBatch := getMetricsFromMetricList(validMetrics1[validSummary], validMetrics2[validSummary])
 
  // len(BucketCount) > len(ExplicitBounds)
@@ -470,6 +472,13 @@ func Test_PushMetrics(t *testing.T) {
  expectedTimeSeries: 12,
  httpResponseCode: http.StatusAccepted,
  },
+ {
+ name: "valid_empty_histogram_case",
+ metrics: &emptyDataPointHistogramBatch,
+ reqTestFunc: checkFunc,
+ expectedTimeSeries: 6,
+ httpResponseCode: http.StatusAccepted,
+ },
  {
  name: "summary_case",
  metrics: &summaryBatch,

exporter/prometheusremotewriteexporter/testutil_test.go

@@ -56,36 +56,39 @@ var (
  quantileValues = []float64{7, 8, 9}
  quantiles = getQuantiles(quantileBounds, quantileValues)
 
- validIntGauge = "valid_IntGauge"
- validDoubleGauge = "valid_DoubleGauge"
- validIntSum = "valid_IntSum"
- validSum = "valid_Sum"
- validHistogram = "valid_Histogram"
- validSummary = "valid_Summary"
- suffixedCounter = "valid_IntSum_total"
+ validIntGauge = "valid_IntGauge"
+ validDoubleGauge = "valid_DoubleGauge"
+ validIntSum = "valid_IntSum"
+ validSum = "valid_Sum"
+ validHistogram = "valid_Histogram"
+ validEmptyHistogram = "valid_empty_Histogram"
+ validSummary = "valid_Summary"
+ suffixedCounter = "valid_IntSum_total"
 
  validIntGaugeDirty = "*valid_IntGauge$"
 
  unmatchedBoundBucketHist = "unmatchedBoundBucketHist"
 
  // valid metrics as input should not return error
  validMetrics1 = map[string]pmetric.Metric{
- validIntGauge: getIntGaugeMetric(validIntGauge, lbs1, intVal1, time1),
- validDoubleGauge: getDoubleGaugeMetric(validDoubleGauge, lbs1, floatVal1, time1),
- validIntSum: getIntSumMetric(validIntSum, lbs1, intVal1, time1),
- suffixedCounter: getIntSumMetric(suffixedCounter, lbs1, intVal1, time1),
- validSum: getSumMetric(validSum, lbs1, floatVal1, time1),
- validHistogram: getHistogramMetric(validHistogram, lbs1, time1, floatVal1, uint64(intVal1), bounds, buckets),
- validSummary: getSummaryMetric(validSummary, lbs1, time1, floatVal1, uint64(intVal1), quantiles),
+ validIntGauge: getIntGaugeMetric(validIntGauge, lbs1, intVal1, time1),
+ validDoubleGauge: getDoubleGaugeMetric(validDoubleGauge, lbs1, floatVal1, time1),
+ validIntSum: getIntSumMetric(validIntSum, lbs1, intVal1, time1),
+ suffixedCounter: getIntSumMetric(suffixedCounter, lbs1, intVal1, time1),
+ validSum: getSumMetric(validSum, lbs1, floatVal1, time1),
+ validHistogram: getHistogramMetric(validHistogram, lbs1, time1, floatVal1, uint64(intVal1), bounds, buckets),
+ validEmptyHistogram: getHistogramMetricEmptyDataPoint(validEmptyHistogram, lbs1, time1),
+ validSummary: getSummaryMetric(validSummary, lbs1, time1, floatVal1, uint64(intVal1), quantiles),
  }
  validMetrics2 = map[string]pmetric.Metric{
- validIntGauge: getIntGaugeMetric(validIntGauge, lbs2, intVal2, time2),
- validDoubleGauge: getDoubleGaugeMetric(validDoubleGauge, lbs2, floatVal2, time2),
- validIntSum: getIntSumMetric(validIntSum, lbs2, intVal2, time2),
- validSum: getSumMetric(validSum, lbs2, floatVal2, time2),
- validHistogram: getHistogramMetric(validHistogram, lbs2, time2, floatVal2, uint64(intVal2), bounds, buckets),
- validSummary: getSummaryMetric(validSummary, lbs2, time2, floatVal2, uint64(intVal2), quantiles),
- validIntGaugeDirty: getIntGaugeMetric(validIntGaugeDirty, lbs1, intVal1, time1),
+ validIntGauge: getIntGaugeMetric(validIntGauge, lbs2, intVal2, time2),
+ validDoubleGauge: getDoubleGaugeMetric(validDoubleGauge, lbs2, floatVal2, time2),
+ validIntSum: getIntSumMetric(validIntSum, lbs2, intVal2, time2),
+ validSum: getSumMetric(validSum, lbs2, floatVal2, time2),
+ validHistogram: getHistogramMetric(validHistogram, lbs2, time2, floatVal2, uint64(intVal2), bounds, buckets),
+ validEmptyHistogram: getHistogramMetricEmptyDataPoint(validEmptyHistogram, lbs2, time2),
+ validSummary: getSummaryMetric(validSummary, lbs2, time2, floatVal2, uint64(intVal2), quantiles),
+ validIntGaugeDirty: getIntGaugeMetric(validIntGaugeDirty, lbs1, intVal1, time1),
  unmatchedBoundBucketHist: getHistogramMetric(unmatchedBoundBucketHist, pcommon.NewMap(), 0, 0, 0,
  pcommon.NewImmutableFloat64Slice([]float64{0.1, 0.2, 0.3}),
  pcommon.NewImmutableUInt64Slice([]uint64{1, 2})),
@@ -293,6 +296,17 @@ func getEmptyCumulativeHistogramMetric(name string) pmetric.Metric {
  return metric
 }
 
+func getHistogramMetricEmptyDataPoint(name string, attributes pcommon.Map, ts uint64) pmetric.Metric {
+ metric := pmetric.NewMetric()
+ metric.SetName(name)
+ metric.SetDataType(pmetric.MetricDataTypeHistogram)
+ metric.Histogram().SetAggregationTemporality(pmetric.MetricAggregationTemporalityCumulative)
+ dp := metric.Histogram().DataPoints().AppendEmpty()
+ attributes.CopyTo(dp.Attributes())
+ dp.SetTimestamp(pcommon.Timestamp(ts))
+ return metric
+}
+
 func getHistogramMetric(name string, attributes pcommon.Map, ts uint64, sum float64, count uint64, bounds pcommon.ImmutableFloat64Slice,
  buckets pcommon.ImmutableUInt64Slice) pmetric.Metric {
  metric := pmetric.NewMetric()

pkg/translator/prometheusremotewrite/helper.go

@@ -343,7 +343,9 @@ func addSingleHistogramDataPoint(pt pmetric.HistogramDataPoint, resource pcommon
  if pt.Flags().HasFlag(pmetric.MetricDataPointFlagNoRecordedValue) {
  infBucket.Value = math.Float64frombits(value.StaleNaN)
  } else {
- cumulativeCount += pt.BucketCounts().At(pt.BucketCounts().Len() - 1)
+ if pt.BucketCounts().Len() > 0 {
+ cumulativeCount += pt.BucketCounts().At(pt.BucketCounts().Len() - 1)
+ }
  infBucket.Value = float64(cumulativeCount)
  }
  infLabels := createAttributes(resource, pt.Attributes(), settings.ExternalLabels, nameStr, baseName+bucketStr, leStr, pInfStr)

unreleased/prw-no-hist-panic.yaml

@@ -0,0 +1,11 @@
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: bug_fix
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: exporter/prometheusremotewrite
+
+# A brief description of the change. Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: "Fix a panic when a histogram does not have any buckets"
+
+# One or more tracking issues related to the change
+issues: [12777]