capture code stacktrace (#184)

* simple fix for #22

* add otel_stacktrace

* generate code for otel stacktrace

* copy otel stacktrace to internal model

* only relevant for spans not transactions

* add test

* go with a sub-object for span.code.stacktrace

* switch bach to a nested structure

* update generated code

* create nested object when reading pb

* fix rum tests

* fix otel tests

* fix intake v2 tests

* move to top-level field

* fix test and write to json doc

* add missing bits

* use untruncated value for code stacktrace

* remove code from span

---------

Co-authored-by: Silvia Mitter <silvia.mitter@elastic.co>

Makefile

@@ -14,9 +14,11 @@ protolint:
 gomodtidy:
 	go mod tidy -v
 
-generate:
+generate_code:
 	go generate ./...
 
+generate: generate_code update-licenses
+
 fieldalignment:
 	go run golang.org/x/tools/go/analysis/passes/fieldalignment/cmd/fieldalignment@v0.4.0 -test=false $(shell go list ./... | grep -v modeldecoder/generator | grep -v test | grep -v model/modelpb)
 

input/elasticapm/internal/modeldecoder/v2/metadata_test.go

@@ -55,6 +55,8 @@ func isUnmappedMetadataField(key string) bool {
 		"client.ip",
 		"client.port",
 		"cloud.origin",
+		"code",
+		"code.stacktrace",
 		"container.runtime",
 		"container.image_name",
 		"container.image_tag",

input/otlp/traces.go

@@ -76,6 +76,7 @@ const (
 	attributeUrlFull                    = "url.full"
 	attributeUserAgentOriginal          = "user_agent.original"
 	attributeDbElasticsearchClusterName = "db.elasticsearch.cluster.name"
+	attributeStackTrace                 = "code.stacktrace" // semconv 1.24 or later
 )
 
 // ConsumeTracesResult contains the number of rejected spans and error message for partial success response.
@@ -754,6 +755,13 @@ func TranslateSpan(spanKind ptrace.SpanKind, attributes pcommon.Map, event *mode
 				httpURL = stringval
 				isHTTP = true
 
+			case attributeStackTrace:
+				if event.Code == nil {
+					event.Code = modelpb.CodeFromVTPool()
+				}
+				// stacktrace is expected to be large thus un-truncated value is needed
+				event.Code.Stacktrace = v.Str()
+
 			// miscellaneous
 			case "span.kind": // filter out
 			case semconv.AttributePeerService:

input/otlp/traces_test.go

@@ -1604,6 +1604,15 @@ func TestGRPCTransactionFromNodejsSDK(t *testing.T) {
 	})
 }
 
+func TestSpanCodeStacktrace(t *testing.T) {
+	t.Run("code stacktrace", func(t *testing.T) {
+		event := transformSpanWithAttributes(t, map[string]interface{}{
+			"code.stacktrace": "stacktrace value",
+		})
+		assert.Equal(t, "stacktrace value", event.Code.Stacktrace)
+	})
+}
+
 func testJaegerLogs() []jaegermodel.Log {
 	return []jaegermodel.Log{{
 		// errors that can be converted to elastic errors

model/modeljson/apmevent.pb.json.go

@@ -248,5 +248,11 @@ func MarshalAPMEvent(e *modelpb.APMEvent, w *fastjson.Writer) error {
 		}
 	}
 
+	if e.Code != nil {
+		doc.Code = &modeljson.Code{
+			Stacktrace: e.Code.Stacktrace,
+		}
+	}
+
 	return doc.MarshalFastJSON(w)
 }

model/modeljson/apmevent.pb.json_test.go

@@ -487,5 +487,8 @@ func fullEvent(t testing.TB) *modelpb.APMEvent {
 			Duration: uint64(3 * time.Second),
 			Severity: 4,
 		},
+		Code: &modelpb.Code{
+			Stacktrace: "stacktrace",
+		},
 	}
 }

model/modeljson/internal/document.go

@@ -67,6 +67,7 @@ type Document struct {
 	Session     *Session     `json:"session,omitempty"`
 	Process     *Process     `json:"process,omitempty"`
 	Event       *Event       `json:"event,omitempty"`
+	Code        *Code        `json:"code,omitempty"`
 
 	Timestamp  Time        `json:"@timestamp"`
 	DataStream *DataStream `json:"data_stream,omitempty"`

model/modeljson/internal/span.go

@@ -35,6 +35,10 @@ type Span struct {
 	RepresentativeCount float64            `json:"representative_count,omitempty"`
 }
 
+type Code struct {
+	Stacktrace string `json:"stacktrace,omitempty"`
+}
+
 type SpanDestination struct {
 	Service SpanDestinationService `json:"service"`
 }

model/modeljson/span.pb.json.go

@@ -93,6 +93,7 @@ func SpanModelJSON(e *modelpb.Span, out *modeljson.Span) {
 			}
 		}
 	}
+
 	if n := len(e.Links); n > 0 {
 		out.Links = make([]modeljson.SpanLink, n)
 		for i, link := range e.Links {