Add gogo/protobuf to OpenTelemetry OTLP data model

cmd/query/app/apiv3/gateway_test.go

@@ -100,6 +100,10 @@ func makeTestTrace() (*model.Trace, model.TraceID) {
 				TraceID:       traceID,
 				SpanID:        model.NewSpanID(180),
 				OperationName: "foobar",
+				Tags: []model.KeyValue{
+					model.String("span.kind", "server"),
+					model.Bool("error", true),
+				},
 			},
 		},
 	}, traceID
@@ -160,9 +164,9 @@ func (gw *testGateway) runGatewayGetTrace(t *testing.T) {
 	parseResponse(t, body, &response)
 
 	assert.Len(t, response.Result.ResourceSpans, 1)
-	assert.Equal(t,
+	assert.EqualValues(t,
 		bytesOfTraceID(t, traceID.High, traceID.Low),
-		response.Result.ResourceSpans[0].ScopeSpans[0].Spans[0].TraceId)
+		response.Result.ResourceSpans[0].ScopeSpans[0].Spans[0].TraceID)
 }
 
 func (gw *testGateway) runGatewayFindTraces(t *testing.T) {
@@ -179,9 +183,9 @@ func (gw *testGateway) runGatewayFindTraces(t *testing.T) {
 	parseResponse(t, body, &response)
 
 	assert.Len(t, response.Result.ResourceSpans, 1)
-	assert.Equal(t,
+	assert.EqualValues(t,
 		bytesOfTraceID(t, traceID.High, traceID.Low),
-		response.Result.ResourceSpans[0].ScopeSpans[0].Spans[0].TraceId)
+		response.Result.ResourceSpans[0].ScopeSpans[0].Spans[0].TraceID)
 }
 
 func bytesOfTraceID(t *testing.T, high, low uint64) []byte {

cmd/query/app/apiv3/http_gateway.go

@@ -124,17 +124,6 @@ func (h *HTTPGateway) returnSpansTestable(
 	if h.tryHandleError(w, err, http.StatusInternalServerError) {
 		return
 	}
-	for _, rs := range resourceSpans {
-		for _, ss := range rs.ScopeSpans {
-			for _, s := range ss.Spans {
-				if len(s.ParentSpanId) == 0 {
-					// If ParentSpanId is empty array then gogo/jsonpb renders it as empty string.
-					// To match the output with grpc-gateway we set it to nil and it won't be included.
-					s.ParentSpanId = nil
-				}
-			}
-		}
-	}
 	response := &api_v3.GRPCGatewayWrapper{
 		Result: &api_v3.SpansResponseChunk{
 			ResourceSpans: resourceSpans,

cmd/query/app/apiv3/snapshots/FindTraces.json

@@ -9,10 +9,14 @@
             "spans": [
               {
                 "endTimeUnixNano": "11651379494838206464",
+                "kind": "SPAN_KIND_SERVER",
                 "name": "foobar",
+                "parentSpanId": "",
                 "spanId": "AAAAAAAAALQ=",
                 "startTimeUnixNano": "11651379494838206464",
-                "status": {},
+                "status": {
+                  "code": "STATUS_CODE_ERROR"
+                },
                 "traceId": "AAAAAAAAAJYAAAAAAAAAoA=="
               }
             ]

cmd/query/app/apiv3/snapshots/GetTrace.json

@@ -9,10 +9,14 @@
             "spans": [
               {
                 "endTimeUnixNano": "11651379494838206464",
+                "kind": "SPAN_KIND_SERVER",
                 "name": "foobar",
+                "parentSpanId": "",
                 "spanId": "AAAAAAAAALQ=",
                 "startTimeUnixNano": "11651379494838206464",
-                "status": {},
+                "status": {
+                  "code": "STATUS_CODE_ERROR"
+                },
                 "traceId": "AAAAAAAAAJYAAAAAAAAAoA=="
               }
             ]

model/v2/customtype.go

@@ -0,0 +1,12 @@
+// Copyright (c) 2024 The Jaeger Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package model
+
+// gogoCustom is an interface that Gogo expects custom types to implement.
+// https://github.com/gogo/protobuf/blob/master/proto/custom_gogo.go#L33
+type gogoCustom interface {
+	Marshal() ([]byte, error)
+	Unmarshal(data []byte) error
+	Size() int
+}

model/v2/empty_test.go

@@ -0,0 +1,14 @@
+// Copyright (c) 2023 The Jaeger Authors.
+// SPDX-License-Identifier: Apache-2.0
+
+package model
+
+import (
+	"testing"
+
+	"go.uber.org/goleak"
+)
+
+func TestMain(m *testing.M) {
+	goleak.VerifyTestMain(m)
+}

model/v2/jsonid.go

@@ -0,0 +1,45 @@
+// Copyright (c) 2023 The Jaeger Authors.
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package model
+
+import (
+	"encoding/base64"
+	"fmt"
+)
+
+// marshalJSON converts trace id into a base64 string enclosed in quotes.
+// Called by Protobuf JSON deserialization.
+func marshalJSON(id []byte) ([]byte, error) {
+	// Plus 2 quote chars at the start and end.
+	hexLen := base64.StdEncoding.EncodedLen(len(id)) + 2
+
+	b := make([]byte, hexLen)
+	base64.StdEncoding.Encode(b[1:hexLen-1], id)
+	b[0], b[hexLen-1] = '"', '"'
+
+	return b, nil
+}
+
+// unmarshalJSON inflates trace id from base64 string, possibly enclosed in quotes.
+// Called by Protobuf JSON deserialization.
+func unmarshalJSON(dst []byte, src []byte) error {
+	if l := len(src); l >= 2 && src[0] == '"' && src[l-1] == '"' {
+		src = src[1 : l-1]
+	}
+	nLen := len(src)
+	if nLen == 0 {
+		return nil
+	}
+
+	if l := base64.StdEncoding.DecodedLen(nLen); len(dst) != l {
+		return fmt.Errorf("invalid length for ID '%s', dst=%d, src=%d", string(src), len(dst), l)
+	}
+
+	_, err := base64.StdEncoding.Decode(dst, src)
+	if err != nil {
+		return fmt.Errorf("cannot unmarshal ID from string '%s': %w", string(src), err)
+	}
+	return nil
+}

model/v2/spanid.go

@@ -0,0 +1,94 @@
+// Copyright (c) 2023 The Jaeger Authors.
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package model
+
+import (
+	"errors"
+
+	"github.com/gogo/protobuf/proto"
+)
+
+const spanIDSize = 8
+
+var (
+	errMarshalSpanID   = errors.New("marshal: invalid buffer length for SpanID")
+	errUnmarshalSpanID = errors.New("unmarshal: invalid SpanID length")
+)
+
+// SpanID is a custom data type that is used for all span_id fields in OTLP
+// Protobuf messages.
+type SpanID [spanIDSize]byte
+
+var (
+	_ proto.Sizer = (*SpanID)(nil)
+	_ gogoCustom  = (*SpanID)(nil)
+)
+
+// Size returns the size of the data to serialize.
+func (sid SpanID) Size() int {
+	if sid.IsEmpty() {
+		return 0
+	}
+	return spanIDSize
+}
+
+// IsEmpty returns true if id contains at least one non-zero byte.
+func (sid SpanID) IsEmpty() bool {
+	return sid == [spanIDSize]byte{}
+}
+
+// MarshalTo converts trace ID into a binary representation. Called by Protobuf serialization.
+func (sid SpanID) MarshalTo(data []byte) (n int, err error) {
+	if sid.IsEmpty() {
+		return 0, nil
+	}
+
+	if len(data) < spanIDSize {
+		return 0, errMarshalSpanID
+	}
+
+	return copy(data, sid[:]), nil
+}
+
+// Marshal implements gogoCustom.
+func (sid *SpanID) Marshal() ([]byte, error) {
+	return sid[:], nil
+}
+
+// Unmarshal inflates this trace ID from binary representation. Called by Protobuf serialization.
+func (sid *SpanID) Unmarshal(data []byte) error {
+	if len(data) == 0 {
+		*sid = [spanIDSize]byte{}
+		return nil
+	}
+
+	if len(data) != spanIDSize {
+		return errUnmarshalSpanID
+	}
+
+	copy(sid[:], data)
+	return nil
+}
+
+// MarshalJSON converts SpanID into a hex string enclosed in quotes.
+func (sid SpanID) MarshalJSON() ([]byte, error) {
+	if sid.IsEmpty() {
+		return []byte(`""`), nil
+	}
+	return marshalJSON(sid[:])
+}
+
+// UnmarshalJSON decodes SpanID from hex string, possibly enclosed in quotes.
+// Called by Protobuf JSON deserialization.
+func (sid *SpanID) UnmarshalJSON(data []byte) error {
+	// in base64 encoding an 8-byte array is padded to 9 bytes
+	buf := [spanIDSize + 1]byte{}
+	if err := unmarshalJSON(buf[:], data); err != nil {
+		return err
+	}
+	*sid = [spanIDSize]byte{}
+	copy(sid[:], buf[:spanIDSize])
+	return nil
+}

model/v2/traceid.go

@@ -0,0 +1,94 @@
+// Copyright (c) 2023 The Jaeger Authors.
+// Copyright The OpenTelemetry Authors
+// SPDX-License-Identifier: Apache-2.0
+
+package model
+
+import (
+	"errors"
+
+	"github.com/gogo/protobuf/proto"
+)
+
+const traceIDSize = 16
+
+var (
+	errMarshalTraceID   = errors.New("marshal: invalid buffer length for TraceID")
+	errUnmarshalTraceID = errors.New("unmarshal: invalid TraceID length")
+)
+
+// TraceID is a custom data type that is used for all trace_id fields in OTLP
+// Protobuf messages.
+type TraceID [traceIDSize]byte
+
+var (
+	_ proto.Sizer = (*TraceID)(nil)
+	_ gogoCustom  = (*TraceID)(nil)
+)
+
+// Size returns the size of the data to serialize.
+func (tid TraceID) Size() int {
+	if tid.IsEmpty() {
+		return 0
+	}
+	return traceIDSize
+}
+
+// IsEmpty returns true if id contains at leas one non-zero byte.
+func (tid TraceID) IsEmpty() bool {
+	return tid == [traceIDSize]byte{}
+}
+
+// Marshal implements gogoCustom.
+func (tid *TraceID) Marshal() ([]byte, error) {
+	return tid[:], nil
+}
+
+// MarshalTo converts trace ID into a binary representation. Called by Protobuf serialization.
+func (tid TraceID) MarshalTo(data []byte) (n int, err error) {
+	if tid.IsEmpty() {
+		return 0, nil
+	}
+
+	if len(data) < traceIDSize {
+		return 0, errMarshalTraceID
+	}
+
+	return copy(data, tid[:]), nil
+}
+
+// Unmarshal inflates this trace ID from binary representation. Called by Protobuf serialization.
+func (tid *TraceID) Unmarshal(data []byte) error {
+	if len(data) == 0 {
+		*tid = [traceIDSize]byte{}
+		return nil
+	}
+
+	if len(data) != traceIDSize {
+		return errUnmarshalTraceID
+	}
+
+	copy(tid[:], data)
+	return nil
+}
+
+// MarshalJSON converts trace id into a hex string enclosed in quotes.
+func (tid TraceID) MarshalJSON() ([]byte, error) {
+	if tid.IsEmpty() {
+		return []byte(`""`), nil
+	}
+	return marshalJSON(tid[:])
+}
+
+// UnmarshalJSON inflates trace id from hex string, possibly enclosed in quotes.
+// Called by Protobuf JSON deserialization.
+func (tid *TraceID) UnmarshalJSON(data []byte) error {
+	// in base64 encoding a 16-byte array is padded to 18 bytes
+	buf := [traceIDSize + 2]byte{}
+	if err := unmarshalJSON(buf[:], data); err != nil {
+		return err
+	}
+	*tid = [traceIDSize]byte{}
+	copy(tid[:], buf[:traceIDSize])
+	return nil
+}