Translate time in parity with old code

receiver/prometheusreceiver/internal/otlp_metricfamily.go

@@ -18,6 +18,7 @@ import (
 	"fmt"
 	"sort"
 	"strings"
+	"time"
 
 	"github.com/prometheus/prometheus/pkg/labels"
 	"github.com/prometheus/prometheus/pkg/textparse"
@@ -174,14 +175,19 @@ func (mg *metricGroupPdata) toDistributionPoint(orderedLabelKeys []string, dest
 	point.SetSum(mg.sum)
 	point.SetBucketCounts(bucketCounts)
 	// The timestamp MUST be in retrieved from milliseconds and converted to nanoseconds.
-	tsNanos := pdata.Timestamp(mg.ts * 1e6)
+	tsNanos := timestampFromMs(mg.ts)
 	point.SetStartTimestamp(tsNanos)
 	point.SetTimestamp(tsNanos)
 	populateLabelValuesPdata(orderedLabelKeys, mg.ls, point.LabelsMap())
 
 	return true
 }
 
+func timestampFromMs(timeAtMs int64) pdata.Timestamp {
+	secs, ns := timeAtMs/1e3, (timeAtMs%1e3)*1e6
+	return pdata.TimestampFromTime(time.Unix(secs, ns))
+}
+
 func (mg *metricGroupPdata) toSummaryPoint(orderedLabelKeys []string, dest *pdata.SummaryDataPointSlice) bool {
 	// expecting count to be provided, however, in the following two cases, they can be missed.
 	// 1. data is corrupted
@@ -205,7 +211,7 @@ func (mg *metricGroupPdata) toSummaryPoint(orderedLabelKeys []string, dest *pdat
 	// observations and the corresponding sum is a sum of all observed values, thus the sum and count used
 	// at the global level of the metricspb.SummaryValue
 	// The timestamp MUST be in retrieved from milliseconds and converted to nanoseconds.
-	tsNanos := pdata.Timestamp(mg.ts * 1e6)
+	tsNanos := timestampFromMs(mg.ts)
 	point.SetStartTimestamp(tsNanos)
 	point.SetTimestamp(tsNanos)
 	point.SetSum(mg.sum)
@@ -217,10 +223,10 @@ func (mg *metricGroupPdata) toSummaryPoint(orderedLabelKeys []string, dest *pdat
 
 func (mg *metricGroupPdata) toNumberDataPoint(orderedLabelKeys []string, dest *pdata.NumberDataPointSlice) bool {
 	var startTsNanos pdata.Timestamp
-	tsNanos := pdata.Timestamp(mg.ts * 1e6)
+	tsNanos := timestampFromMs(mg.ts)
 	// gauge/undefined types have no start time.
 	if mg.family.isCumulativeTypePdata() {
-		startTsNanos = pdata.Timestamp(mg.intervalStartTimeMs * 1e6)
+		startTsNanos = timestampFromMs(mg.intervalStartTimeMs)
 	}
 
 	point := dest.AppendEmpty()

receiver/prometheusreceiver/internal/otlp_transaction.go

@@ -19,6 +19,7 @@ import (
 	"errors"
 	"math"
 	"sync/atomic"
+	"time"
 
 	"go.uber.org/zap"
 
@@ -159,6 +160,7 @@ func (t *transactionPdata) Commit() error {
 	for _, sEntry := range staleLabels {
 		t.metricBuilder.AddDataPoint(sEntry.labels, sEntry.seenAtMs, stalenessSpecialValue)
 	}
+
 	t.startTimeMs = -1
 
 	ctx := t.obsrecv.StartMetricsOp(t.ctx)
@@ -195,28 +197,43 @@ func (t *transactionPdata) Rollback() error {
 	return nil
 }
 
+func timestampFromFloat64(ts float64) pdata.Timestamp {
+	secs := int64(ts)
+	nanos := int64((ts - float64(secs)) * 1e9)
+	return pdata.TimestampFromTime(time.Unix(secs, nanos))
+}
+
 func adjustStartTimestampPdata(startTime float64, metricsL *pdata.MetricSlice) {
+	startTimeTs := timestampFromFloat64(startTime)
 	for i := 0; i < metricsL.Len(); i++ {
 		metric := metricsL.At(i)
 		switch metric.DataType() {
-		case pdata.MetricDataTypeGauge, pdata.MetricDataTypeHistogram:
+		case pdata.MetricDataTypeGauge:
 			continue
 
 		case pdata.MetricDataTypeSum:
 			dataPoints := metric.Sum().DataPoints()
 			for i := 0; i < dataPoints.Len(); i++ {
 				dataPoint := dataPoints.At(i)
-				dataPoint.SetStartTimestamp(pdata.Timestamp(startTime))
+				dataPoint.SetStartTimestamp(startTimeTs)
 			}
 
 		case pdata.MetricDataTypeSummary:
 			dataPoints := metric.Summary().DataPoints()
 			for i := 0; i < dataPoints.Len(); i++ {
 				dataPoint := dataPoints.At(i)
-				dataPoint.SetStartTimestamp(pdata.Timestamp(startTime))
+				dataPoint.SetStartTimestamp(startTimeTs)
+			}
+
+		case pdata.MetricDataTypeHistogram:
+		dataPoints := metric.Histogram().DataPoints()
+			for i := 0; i < dataPoints.Len(); i++ {
+				dataPoint := dataPoints.At(i)
+				dataPoint.SetStartTimestamp(startTimeTs)
 			}
 
 		default:
+			panic("Unknown type:: " + metric.DataType().String())
 		}
 	}
 }