Use custom data type and custom JSON serialization for traceid (#1840)

Contributes to #1177

1. The TraceID type uses custom data type so that JSON serialization
is in hex format instead of base64 (which is the default Protobuf JSON
format). Hex format is required by OTLP spec:
https://github.com/open-telemetry/opentelemetry-specification/blob/master/specification/protocol/otlp.md#request
SpanID must be also modified similarly. Will be done in a future PR
to avoid creating a huge PR.

2. Moved pdata.TraceID to its own file. Note that there is pdata.TraceID which
is different from otlp TraceID custom data type. Due to the way packages are
structured we need both to keep OTLP generated data types decoupled from pdata
data types.

The majority of the changes in this commit are simply type changes from
[]byte to TraceID.

Makefile

@@ -277,6 +277,9 @@ genproto_sub:
 	sed -f proto_patch.sed $(OPENTELEMETRY_PROTO_SRC_DIR)/opentelemetry/proto/logs/v1/logs.proto \
 	   > $(PROTO_INTERMEDIATE_DIR)/opentelemetry/proto/logs/v1/logs.proto
 
+	sed -f proto_patch.sed $(OPENTELEMETRY_PROTO_SRC_DIR)/opentelemetry/proto/metrics/v1/metrics.proto \
+	   > $(PROTO_INTERMEDIATE_DIR)/opentelemetry/proto/metrics/v1/metrics.proto
+
 	@echo Generate Go code from .proto files in intermediate directory.
 	$(foreach file,$(OPENTELEMETRY_PROTO_FILES),$(call exec-command,cd $(PROTO_INTERMEDIATE_DIR) && protoc --gogofaster_out=plugins=grpc:./ -I./ -I$(GO_PKG_DIR) $(file)))
 

cmd/pdatagen/internal/log_structs.go

@@ -17,6 +17,7 @@ package internal
 var logFile = &File{
 	Name: "log",
 	imports: []string{
+		`otlpcommon "go.opentelemetry.io/collector/internal/data/opentelemetry-proto-gen/common/v1"`,
 		`otlplogs "go.opentelemetry.io/collector/internal/data/opentelemetry-proto-gen/logs/v1"`,
 	},
 	testImports: []string{

cmd/pdatagen/internal/trace_structs.go

@@ -17,6 +17,7 @@ package internal
 var traceFile = &File{
 	Name: "trace",
 	imports: []string{
+		`otlpcommon "go.opentelemetry.io/collector/internal/data/opentelemetry-proto-gen/common/v1"`,
 		`otlptrace "go.opentelemetry.io/collector/internal/data/opentelemetry-proto-gen/trace/v1"`,
 	},
 	testImports: []string{
@@ -204,7 +205,7 @@ var traceIDField = &primitiveTypedField{
 	fieldName:       "TraceID",
 	originFieldName: "TraceId",
 	returnType:      "TraceID",
-	rawType:         "[]byte",
+	rawType:         "otlpcommon.TraceID",
 	defaultVal:      "NewTraceID(nil)",
 	testVal:         "NewTraceID([]byte{1, 2, 3, 4, 5, 6, 7, 8, 8, 7, 6, 5, 4, 3, 2, 1})",
 }

consumer/pdata/metric_test.go

@@ -156,7 +156,7 @@ func TestResourceMetricsWireCompatibility(t *testing.T) {
 
 	// Now compare that the original and final ProtoBuf messages are the same.
 	// This proves that goproto and gogoproto marshaling/unmarshaling are wire compatible.
-	assert.True(t, gogoproto.Equal(*pdataRM.orig, &gogoprotoRM))
+	assert.True(t, assert.EqualValues(t, *pdataRM.orig, &gogoprotoRM))
 }
 
 func TestMetricCount(t *testing.T) {

consumer/pdata/trace.go

@@ -105,17 +105,6 @@ func (td Traces) ResourceSpans() ResourceSpansSlice {
 	return newResourceSpansSlice(td.orig)
 }
 
-type TraceID []byte
-
-// NewTraceID returns a new TraceID.
-func NewTraceID(bytes []byte) TraceID { return bytes }
-
-func (t TraceID) Bytes() []byte {
-	return t
-}
-
-func (t TraceID) String() string { return hex.EncodeToString(t) }
-
 type SpanID []byte
 
 // NewSpanID returns a new SpanID.

consumer/pdata/trace_test.go

@@ -140,7 +140,7 @@ func TestResourceSpansWireCompatibility(t *testing.T) {
 
 	// Now compare that the original and final ProtoBuf messages are the same.
 	// This proves that goproto and gogoproto marshaling/unmarshaling are wire compatible.
-	assert.True(t, gogoproto.Equal(*pdataRS.orig, &gogoprotoRS2))
+	assert.EqualValues(t, *pdataRS.orig, &gogoprotoRS2)
 }
 
 func TestTraces_ToOtlpProtoBytes(t *testing.T) {

consumer/pdata/traceid.go

@@ -0,0 +1,34 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//       http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package pdata
+
+import (
+	otlpcommon "go.opentelemetry.io/collector/internal/data/opentelemetry-proto-gen/common/v1"
+)
+
+// TraceID is an alias of OTLP TraceID data type.
+type TraceID otlpcommon.TraceID
+
+func NewTraceID(bytes []byte) TraceID {
+	return TraceID(otlpcommon.NewTraceID(bytes))
+}
+
+func (t TraceID) Bytes() []byte {
+	return otlpcommon.TraceID(t).Bytes()
+}
+
+func (t TraceID) HexString() string {
+	return otlpcommon.TraceID(t).HexString()
+}

exporter/jaegerexporter/exporter_test.go

@@ -32,6 +32,7 @@ import (
 	"go.opentelemetry.io/collector/config/configgrpc"
 	"go.opentelemetry.io/collector/config/configtls"
 	"go.opentelemetry.io/collector/consumer/pdata"
+	otlpcommon "go.opentelemetry.io/collector/internal/data/opentelemetry-proto-gen/common/v1"
 	tracev1 "go.opentelemetry.io/collector/internal/data/opentelemetry-proto-gen/trace/v1"
 	"go.opentelemetry.io/collector/internal/data/testdata"
 )
@@ -226,7 +227,7 @@ func TestMutualTLS(t *testing.T) {
 	require.NoError(t, err)
 	defer exporter.Shutdown(context.Background())
 
-	traceID := []byte("0123456789abcdef")
+	traceID := otlpcommon.NewTraceID([]byte{0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15})
 	spanID := []byte("01234567")
 	traces := pdata.TracesFromOtlp([]*tracev1.ResourceSpans{
 		{InstrumentationLibrarySpans: []*tracev1.InstrumentationLibrarySpans{{Spans: []*tracev1.Span{{TraceId: traceID, SpanId: spanID}}}}},
@@ -235,7 +236,7 @@ func TestMutualTLS(t *testing.T) {
 	require.NoError(t, err)
 	requestes := spanHandler.getRequests()
 	assert.Equal(t, 1, len(requestes))
-	jTraceID, err := model.TraceIDFromBytes(traceID)
+	jTraceID, err := model.TraceIDFromBytes(traceID.Bytes())
 	require.NoError(t, err)
 	assert.Equal(t, jTraceID, requestes[0].GetBatch().Spans[0].TraceID)
 }

exporter/loggingexporter/logging_exporter.go

@@ -254,7 +254,7 @@ func (b *logDataBuffer) logLinks(description string, sl pdata.SpanLinkSlice) {
 			continue
 		}
 		b.logEntry("SpanLink #%d", i)
-		b.logEntry("     -> Trace ID: %s", l.TraceID().String())
+		b.logEntry("     -> Trace ID: %s", l.TraceID().HexString())
 		b.logEntry("     -> ID: %s", l.SpanID().String())
 		b.logEntry("     -> TraceState: %s", l.TraceState())
 		b.logEntry("     -> DroppedAttributesCount: %d", l.DroppedAttributesCount())
@@ -332,7 +332,7 @@ func (s *loggingExporter) pushTraceData(
 					continue
 				}
 
-				buf.logAttr("Trace ID", span.TraceID().String())
+				buf.logAttr("Trace ID", span.TraceID().HexString())
 				buf.logAttr("Parent ID", span.ParentSpanID().String())
 				buf.logAttr("ID", span.SpanID().String())
 				buf.logAttr("Name", span.Name())