enable 128bit logging by default

contrib/log/slog/slog.go

@@ -10,13 +10,16 @@ import (
 	"context"
 	"io"
 	"log/slog"
+	"os"
 	"strconv"
 
 	"github.com/DataDog/dd-trace-go/v2/ddtrace/ext"
 	"github.com/DataDog/dd-trace-go/v2/ddtrace/tracer"
 	"github.com/DataDog/dd-trace-go/v2/instrumentation"
 )
 
+var cfg = newConfig()
+
 func init() {
 	_ = instrumentation.Load(instrumentation.PackageLogSlog)
 }
@@ -28,6 +31,16 @@ type group struct {
 	attrs []slog.Attr
 }
 
+type config struct {
+	log128bits bool
+}
+
+func newConfig() *config {
+	return &config{
+		log128bits: os.Getenv("DD_TRACE_128_BIT_TRACEID_LOGGING_ENABLED") != "false",
+	}
+}
+
 // NewJSONHandler is a convenience function that returns a *slog.JSONHandler logger enhanced with
 // tracing information.
 func NewJSONHandler(w io.Writer, opts *slog.HandlerOptions) slog.Handler {
@@ -59,7 +72,13 @@ func (h *handler) Handle(ctx context.Context, rec slog.Record) error {
 	// set them at the root level.
 	span, ok := tracer.SpanFromContext(ctx)
 	if ok && span.Context().TraceID() != tracer.TraceIDZero {
-		traceID := span.Context().TraceID()
+		var traceID string
+		if cfg.log128bits {
+			traceID = span.Context().TraceID()
+		} else {
+			traceID = strconv.FormatUint(span.Context().TraceIDLower(), 10)
+		}
+
 		spanID := strconv.FormatUint(span.Context().SpanID(), 10)
 
 		attrs := []slog.Attr{

contrib/log/slog/slog_test.go

@@ -11,6 +11,7 @@ import (
 	"encoding/json"
 	"io"
 	"log/slog"
+	"os"
 	"strconv"
 	"strings"
 	"testing"
@@ -24,7 +25,7 @@ import (
 	"github.com/DataDog/dd-trace-go/v2/instrumentation/testutils"
 )
 
-func assertLogEntry(t *testing.T, rawEntry, wantMsg, wantLevel string, span *tracer.Span, assertExtra func(t *testing.T, entry map[string]interface{})) {
+func assertLogEntry(t *testing.T, rawEntry, wantMsg, wantLevel string, traceID string, spanID string, assertExtra func(t *testing.T, entry map[string]interface{})) {
 	t.Helper()
 
 	t.Log(rawEntry)
@@ -38,8 +39,6 @@ func assertLogEntry(t *testing.T, rawEntry, wantMsg, wantLevel string, span *tra
 	assert.Equal(t, wantLevel, entry["level"])
 	assert.NotEmpty(t, entry["time"])
 
-	traceID := span.Context().TraceID()
-	spanID := strconv.FormatUint(span.Context().SpanID(), 10)
 	assert.Equal(t, traceID, entry[ext.LogKeyTraceID], "trace id not found")
 	assert.Equal(t, spanID, entry[ext.LogKeySpanID], "span id not found")
 
@@ -81,6 +80,16 @@ func testLogger(t *testing.T, createLogger func(b io.Writer) *slog.Logger, asser
 	span, ctx := tracer.StartSpanFromContext(context.Background(), "test")
 	defer span.Finish()
 
+	var traceID string
+	spanID := strconv.FormatUint(span.Context().SpanID(), 10)
+	if os.Getenv("DD_TRACE_128_BIT_TRACEID_LOGGING_ENABLED") == "false" {
+		// Re-initialize to account for race condition between setting env var in the test and reading it in the contrib
+		cfg = newConfig()
+		traceID = strconv.FormatUint(span.Context().TraceIDLower(), 10)
+	} else {
+		traceID = span.Context().TraceID()
+	}
+
 	// log a message using the context containing span information
 	logger.Log(ctx, slog.LevelInfo, "this is an info log with tracing information")
 	logger.Log(ctx, slog.LevelError, "this is an error log with tracing information")
@@ -91,8 +100,8 @@ func testLogger(t *testing.T, createLogger func(b io.Writer) *slog.Logger, asser
 	)
 	// assert log entries contain trace information
 	require.Len(t, logs, 2)
-	assertLogEntry(t, logs[0], "this is an info log with tracing information", "INFO", span, assertExtra)
-	assertLogEntry(t, logs[1], "this is an error log with tracing information", "ERROR", span, assertExtra)
+	assertLogEntry(t, logs[0], "this is an info log with tracing information", "INFO", traceID, spanID, assertExtra)
+	assertLogEntry(t, logs[1], "this is an error log with tracing information", "ERROR", traceID, spanID, assertExtra)
 }
 
 func testLoggerNoTrace(t *testing.T, createLogger func(b io.Writer) *slog.Logger) {
@@ -252,6 +261,20 @@ func TestRecordClone(t *testing.T) {
 	assert.True(t, foundSentinel)
 }
 
+func Test128BitLoggingDisabled(t *testing.T) {
+	os.Setenv("DD_TRACE_128_BIT_TRACEID_LOGGING_ENABLED", "false")
+	defer os.Unsetenv("DD_TRACE_128_BIT_TRACEID_LOGGING_ENABLED")
+	t.Run("testLogger", func(t *testing.T) {
+		testLogger(
+			t,
+			func(w io.Writer) *slog.Logger {
+				return slog.New(WrapHandler(slog.NewJSONHandler(w, nil)))
+			},
+			nil,
+		)
+	})
+}
+
 func BenchmarkHandler(b *testing.B) {
 	span, ctx := tracer.StartSpanFromContext(context.Background(), "test")
 	defer span.Finish()

contrib/sirupsen/logrus/logrus.go

@@ -7,6 +7,9 @@
 package logrus
 
 import (
+	"os"
+	"strconv"
+
 	"github.com/DataDog/dd-trace-go/v2/ddtrace/ext"
 	"github.com/DataDog/dd-trace-go/v2/ddtrace/tracer"
 	"github.com/DataDog/dd-trace-go/v2/instrumentation"
@@ -23,6 +26,18 @@ func init() {
 // DDContextLogHook ensures that any span in the log context is correlated to log output.
 type DDContextLogHook struct{}
 
+type config struct {
+	log128bits bool
+}
+
+var cfg = newConfig()
+
+func newConfig() *config {
+	return &config{
+		log128bits: os.Getenv("DD_TRACE_128_BIT_TRACEID_LOGGING_ENABLED") != "false",
+	}
+}
+
 // Levels implements logrus.Hook interface, this hook applies to all defined levels
 func (d *DDContextLogHook) Levels() []logrus.Level {
 	return []logrus.Level{logrus.PanicLevel, logrus.FatalLevel, logrus.ErrorLevel, logrus.WarnLevel, logrus.InfoLevel, logrus.DebugLevel, logrus.TraceLevel}
@@ -34,7 +49,11 @@ func (d *DDContextLogHook) Fire(e *logrus.Entry) error {
 	if !found {
 		return nil
 	}
-	e.Data[ext.LogKeyTraceID] = span.Context().TraceID()
-	e.Data[ext.LogKeySpanID] = span.Context().SpanID()
+	if cfg.log128bits && span.Context().TraceID() != tracer.TraceIDZero {
+		e.Data[ext.LogKeyTraceID] = span.Context().TraceID()
+	} else {
+		e.Data[ext.LogKeyTraceID] = strconv.FormatUint(span.Context().TraceIDLower(), 10)
+	}
+	e.Data[ext.LogKeySpanID] = strconv.FormatUint(span.Context().SpanID(), 10)
 	return nil
 }

contrib/sirupsen/logrus/logrus_test.go

@@ -7,6 +7,7 @@ package logrus
 
 import (
 	"context"
+	"strconv"
 	"testing"
 
 	"github.com/DataDog/dd-trace-go/v2/ddtrace/tracer"
@@ -24,8 +25,29 @@ func TestFire(t *testing.T) {
 	e := logrus.NewEntry(logrus.New())
 	e.Context = sctx
 	err := hook.Fire(e)
-
 	assert.NoError(t, err)
+
+	// By default, trace IDs are logged in 128bit format
 	assert.Equal(t, sp.Context().TraceID(), e.Data["dd.trace_id"])
-	assert.Equal(t, sp.Context().SpanID(), e.Data["dd.span_id"])
+	assert.Equal(t, strconv.FormatUint(sp.Context().SpanID(), 10), e.Data["dd.span_id"])
+}
+
+func TestFire128BitDisabled(t *testing.T) {
+	t.Setenv("DD_TRACE_128_BIT_TRACEID_LOGGING_ENABLED", "false")
+
+	// Re-initialize to account for race condition between setting env var in the test and reading it in the contrib
+	cfg = newConfig()
+
+	tracer.Start()
+	defer tracer.Stop()
+	sp, sctx := tracer.StartSpanFromContext(context.Background(), "testSpan", tracer.WithSpanID(1234))
+
+	hook := &DDContextLogHook{}
+	e := logrus.NewEntry(logrus.New())
+	e.Context = sctx
+	err := hook.Fire(e)
+	assert.NoError(t, err)
+
+	assert.Equal(t, strconv.FormatUint(sp.Context().TraceIDLower(), 10), e.Data["dd.trace_id"])
+	assert.Equal(t, strconv.FormatUint(sp.Context().SpanID(), 10), e.Data["dd.span_id"])
 }

ddtrace/tracer/log_test.go

@@ -187,9 +187,9 @@ func TestLogFormat(t *testing.T) {
 	defer stop()
 	tp.Reset()
 	tp.Ignore("appsec: ", telemetry.LogPrefix)
-	tracer.StartSpan("test", ServiceName("test-service"), ResourceName("/"), WithSpanID(12345))
+	span := tracer.StartSpan("test", ServiceName("test-service"), ResourceName("/"), WithSpanID(12345))
 	assert.Len(tp.Logs(), 1)
-	assert.Regexp(logPrefixRegexp+` DEBUG: Started Span: dd.trace_id="12345" dd.span_id="12345" dd.parent_id="0", Operation: test, Resource: /, Tags: map.*, map.*`, tp.Logs()[0])
+	assert.Regexp(logPrefixRegexp+` DEBUG: Started Span: dd.trace_id="`+span.Context().TraceID()+`" dd.span_id="12345" dd.parent_id="0", Operation: test, Resource: /, Tags: map.*, map.*`, tp.Logs()[0])
 }
 
 func TestLogPropagators(t *testing.T) {

ddtrace/tracer/span.go

@@ -791,7 +791,7 @@ func (s *Span) Format(f fmt.State, c rune) {
 			}
 		}
 		var traceID string
-		if sharedinternal.BoolEnv("DD_TRACE_128_BIT_TRACEID_LOGGING_ENABLED", false) && s.context.traceID.HasUpper() {
+		if sharedinternal.BoolEnv("DD_TRACE_128_BIT_TRACEID_LOGGING_ENABLED", true) && s.context.traceID.HasUpper() {
 			traceID = s.context.TraceID()
 		} else {
 			traceID = fmt.Sprintf("%d", s.traceID)