fix handling of null values in OpenTelemetry arrays

Author: vadimalekseev

app/vlinsert/opentelemetry/opentelemetry_test.go

@@ -356,6 +356,12 @@ func TestPushProtobufRequest(t *testing.T) {
 	timestampsExpected = []int64{1234}
 	resultsExpected = `{"_msg":"[\"Zm9vIGJhcg==\"]","severity":"Unspecified"}`
 	f(data, timestampsExpected, resultsExpected)
+
+	// decode null in ArrayValue
+	data = `[{"scopeLogs":[{"logRecords":[{"timeUnixNano":1234,"body":{"arrayValue":{"values":[null,{}]}}}]}]}]`
+	timestampsExpected = []int64{1234}
+	resultsExpected = `{"_msg":"[null,null]","severity":"Unspecified"}`
+	f(data, timestampsExpected, resultsExpected)
 }
 
 var mp easyproto.MarshalerPool
@@ -430,6 +436,9 @@ type anyValue struct {
 }
 
 func (av *anyValue) marshalProtobuf(mm *easyproto.MessageMarshaler) {
+	if av == nil {
+		return
+	}
 	switch {
 	case av.StringValue != nil:
 		mm.AppendString(1, *av.StringValue)

app/vlinsert/opentelemetry/pb_json.go

@@ -125,7 +125,7 @@ func decodeAnyValueToJSON(src []byte, a *fastjson.Arena, fb *fmtBuffer) (*fastjs
 			return a.NewString(v), nil
 		}
 	}
-	return nil, nil
+	return a.NewNull(), nil
 }
 
 func decodeKeyValueListToJSON(src []byte, a *fastjson.Arena, fb *fmtBuffer) (*fastjson.Value, error) {

docs/victorialogs/CHANGELOG.md

@@ -23,6 +23,8 @@ according to the follosing docs:
 
 * FEATURE: [OpenTelemetry data ingestion](https://docs.victoriametrics.com/victorialogs/data-ingestion/opentelemetry/): parse [`scope` inside ScopeLogs](https://github.com/open-telemetry/opentelemetry-proto/blob/a5f0eac5b802f7ae51dfe41e5116fe5548955e64/opentelemetry/proto/logs/v1/logs.proto#L72) and store it into [log fields](https://docs.victoriametrics.com/victorialogs/keyconcepts/#data-model) starting with `scope.` prefix. See [#826](https://github.com/VictoriaMetrics/VictoriaLogs/issues/826).
 
+* BUGFIX: [OpenTelemetry data ingestion](https://docs.victoriametrics.com/victorialogs/data-ingestion/opentelemetry/): properly handle `null` values inside arrays. Previously, such arrays could cause a panic during ingestion. See [#869](https://github.com/VictoriaMetrics/VictoriaLogs/issues/869#issuecomment-3627177567).
+
 ## [v1.40.0](https://github.com/VictoriaMetrics/VictoriaLogs/releases/tag/v1.40.0)
 
 Released at 2025-12-05