[exporter/prometheusremotewrite] respect integer exemplar values (#36688

)

Co-authored-by: Evan Bradley <[email protected]>

.chloggen/exporter_prometheusremotewriteexporter_exemplar-int.yaml

@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# 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 exemplar handling when the exemplar is an integer value.
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [36657]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext: Send metrics with exemplars as integer values now are correctly handled.
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: [user]

pkg/translator/prometheusremotewrite/helper.go

@@ -301,9 +301,18 @@ func getPromExemplars[T exemplarType](pt T) []prompb.Exemplar {
 		exemplar := pt.Exemplars().At(i)
 		exemplarRunes := 0
 
-		promExemplar := prompb.Exemplar{
-			Value:     exemplar.DoubleValue(),
-			Timestamp: timestamp.FromTime(exemplar.Timestamp().AsTime()),
+		var promExemplar prompb.Exemplar
+		switch exemplar.ValueType() {
+		case pmetric.ExemplarValueTypeInt:
+			promExemplar = prompb.Exemplar{
+				Value:     float64(exemplar.IntValue()),
+				Timestamp: timestamp.FromTime(exemplar.Timestamp().AsTime()),
+			}
+		case pmetric.ExemplarValueTypeDouble:
+			promExemplar = prompb.Exemplar{
+				Value:     exemplar.DoubleValue(),
+				Timestamp: timestamp.FromTime(exemplar.Timestamp().AsTime()),
+			}
 		}
 		if traceID := exemplar.TraceID(); !traceID.IsEmpty() {
 			val := hex.EncodeToString(traceID[:])

pkg/translator/prometheusremotewrite/helper_test.go

@@ -479,6 +479,17 @@ func Test_getPromExemplars(t *testing.T) {
 				},
 			},
 		},
+		{
+			"with_exemplars_int_value",
+			getHistogramDataPointWithExemplars(t, tnow, intVal2, traceIDValue1, spanIDValue1, label11, value11),
+			[]prompb.Exemplar{
+				{
+					Value:     float64(intVal2),
+					Timestamp: timestamp.FromTime(tnow),
+					Labels:    []prompb.Label{getLabel(prometheustranslator.ExemplarTraceIDKey, traceIDValue1), getLabel(prometheustranslator.ExemplarSpanIDKey, spanIDValue1), getLabel(label11, value11)},
+				},
+			},
+		},
 		{
 			"too_many_runes_drops_labels",
 			getHistogramDataPointWithExemplars(t, tnow, floatVal1, "", "", keyWith129Runes, ""),

pkg/translator/prometheusremotewrite/testutils_test.go

@@ -184,11 +184,16 @@ func getTimeSeriesWithSamplesAndExemplars(labels []prompb.Label, samples []promp
 	}
 }
 
-func getHistogramDataPointWithExemplars(t *testing.T, time time.Time, value float64, traceID string, spanID string, attributeKey string, attributeValue string) pmetric.HistogramDataPoint {
+func getHistogramDataPointWithExemplars[V int64 | float64](t *testing.T, time time.Time, value V, traceID string, spanID string, attributeKey string, attributeValue string) pmetric.HistogramDataPoint {
 	h := pmetric.NewHistogramDataPoint()
 
 	e := h.Exemplars().AppendEmpty()
-	e.SetDoubleValue(value)
+	switch v := (any)(value).(type) {
+	case int64:
+		e.SetIntValue(v)
+	case float64:
+		e.SetDoubleValue(v)
+	}
 	e.SetTimestamp(pcommon.NewTimestampFromTime(time))
 	if attributeKey != "" || attributeValue != "" {
 		e.FilteredAttributes().PutStr(attributeKey, attributeValue)