Fix resource attribute mutation bug (#907)

This commit fixes a bug when "service.name" attribute is removed from resource structure during translation to jaeger proto format

Author: dmitryax

translator/trace/jaeger/traces_to_jaegerproto.go

@@ -117,42 +117,60 @@ func resourceToJaegerProtoProcess(resource pdata.Resource) *model.Process {
 	process := model.Process{}
 	if serviceName, ok := attrs.Get(conventions.AttributeServiceName); ok {
 		process.ServiceName = serviceName.StringVal()
-		attrs.Delete(conventions.AttributeServiceName)
 	}
-	process.Tags = attributesToJaegerProtoTags(attrs)
+	process.Tags = resourceAttributesToJaegerProtoTags(attrs)
 	return &process
 
 }
 
-func attributesToJaegerProtoTags(attrs pdata.AttributeMap) []model.KeyValue {
+func resourceAttributesToJaegerProtoTags(attrs pdata.AttributeMap) []model.KeyValue {
 	if attrs.Cap() == 0 {
 		return nil
 	}
 
 	tags := make([]model.KeyValue, 0, attrs.Cap())
 	attrs.ForEach(func(key string, attr pdata.AttributeValue) {
-		tag := model.KeyValue{Key: key}
-		switch attr.Type() {
-		case pdata.AttributeValueSTRING:
-			// Jaeger-to-Internal maps binary tags to string attributes and encodes them as
-			// base64 strings. Blindingly attempting to decode base64 seems too much.
-			tag.VType = model.ValueType_STRING
-			tag.VStr = attr.StringVal()
-		case pdata.AttributeValueINT:
-			tag.VType = model.ValueType_INT64
-			tag.VInt64 = attr.IntVal()
-		case pdata.AttributeValueBOOL:
-			tag.VType = model.ValueType_BOOL
-			tag.VBool = attr.BoolVal()
-		case pdata.AttributeValueDOUBLE:
-			tag.VType = model.ValueType_FLOAT64
-			tag.VFloat64 = attr.DoubleVal()
+		if key == conventions.AttributeServiceName {
+			return
 		}
-		tags = append(tags, tag)
+		tags = append(tags, attributeToJaegerProtoTag(key, attr))
 	})
 	return tags
 }
 
+func attributesToJaegerProtoTags(attrs pdata.AttributeMap) []model.KeyValue {
+	if attrs.Cap() == 0 {
+		return nil
+	}
+
+	tags := make([]model.KeyValue, 0, attrs.Cap())
+	attrs.ForEach(func(key string, attr pdata.AttributeValue) {
+		tags = append(tags, attributeToJaegerProtoTag(key, attr))
+	})
+	return tags
+}
+
+func attributeToJaegerProtoTag(key string, attr pdata.AttributeValue) model.KeyValue {
+	tag := model.KeyValue{Key: key}
+	switch attr.Type() {
+	case pdata.AttributeValueSTRING:
+		// Jaeger-to-Internal maps binary tags to string attributes and encodes them as
+		// base64 strings. Blindingly attempting to decode base64 seems too much.
+		tag.VType = model.ValueType_STRING
+		tag.VStr = attr.StringVal()
+	case pdata.AttributeValueINT:
+		tag.VType = model.ValueType_INT64
+		tag.VInt64 = attr.IntVal()
+	case pdata.AttributeValueBOOL:
+		tag.VType = model.ValueType_BOOL
+		tag.VBool = attr.BoolVal()
+	case pdata.AttributeValueDOUBLE:
+		tag.VType = model.ValueType_FLOAT64
+		tag.VFloat64 = attr.DoubleVal()
+	}
+	return tag
+}
+
 func spanToJaegerProto(span pdata.Span) (*model.Span, error) {
 	if span.IsNil() {
 		return nil, nil

translator/trace/jaeger/traces_to_jaegerproto_test.go

@@ -24,6 +24,7 @@ import (
 
 	"github.com/open-telemetry/opentelemetry-collector/consumer/pdata"
 	"github.com/open-telemetry/opentelemetry-collector/internal/data/testdata"
+	"github.com/open-telemetry/opentelemetry-collector/translator/conventions"
 	tracetranslator "github.com/open-telemetry/opentelemetry-collector/translator/trace"
 )
 
@@ -188,6 +189,7 @@ func TestAttributesToJaegerProtoTags(t *testing.T) {
 	attributes.InsertInt("int-val", 123)
 	attributes.InsertString("string-val", "abc")
 	attributes.InsertDouble("double-val", 1.23)
+	attributes.InsertString(conventions.AttributeServiceName, "service-name")
 
 	expected := []model.KeyValue{
 		{
@@ -210,9 +212,21 @@ func TestAttributesToJaegerProtoTags(t *testing.T) {
 			VType:    model.ValueType_FLOAT64,
 			VFloat64: 1.23,
 		},
+		{
+			Key:   conventions.AttributeServiceName,
+			VType: model.ValueType_STRING,
+			VStr:  "service-name",
+		},
 	}
 
 	require.EqualValues(t, expected, attributesToJaegerProtoTags(attributes))
+
+	got := attributesToJaegerProtoTags(attributes)
+	require.EqualValues(t, expected, got)
+
+	// The last item in expected ("service-name") must be skipped in resource tags translation
+	got = resourceAttributesToJaegerProtoTags(attributes)
+	require.EqualValues(t, expected[:4], got)
 }
 
 func TestInternalTracesToJaegerProto(t *testing.T) {