feat: add slog/logr logging bridges and update shared utilities

- Add slog/logr bridge in pkg/log/zap.go for Cilium v1.19
- Update pkg/utils/flow_utils.go with structpb extensions
- Migrate metrics package to slog-compatible interface
- Remove unused ITracer mock
- Update pkg/config, pkg/common/endpoint.go, and Hubble decoder

Signed-off-by: Quang Nguyen <nguyenquang@microsoft.com>

Author: nddq

pkg/common/endpoint.go

@@ -164,7 +164,7 @@ func (ep *RetinaEndpoint) PrimaryIP() (string, error) {
 		}
 	}
 
-	return "", errors.Wrapf(ErrNoPrimaryIPFoundEndpoint, ep.Key())
+	return "", errors.Wrapf(ErrNoPrimaryIPFoundEndpoint, "endpoint: %s", ep.Key())
 }
 
 func (ep *RetinaEndpoint) PrimaryNetIP() (net.IP, error) {
@@ -178,7 +178,7 @@ func (ep *RetinaEndpoint) PrimaryNetIP() (net.IP, error) {
 		}
 	}
 
-	return nil, errors.Wrapf(ErrNoPrimaryIPFoundEndpoint, ep.Key())
+	return nil, errors.Wrapf(ErrNoPrimaryIPFoundEndpoint, "endpoint: %s", ep.Key())
 }
 
 func (o *OwnerReference) DeepCopy() *OwnerReference {

pkg/hubble/common/decoder_linux.go

@@ -10,8 +10,6 @@ import (
 	"github.com/cilium/cilium/pkg/labels"
 )
 
-//go:generate go run github.com/golang/mock/mockgen@v1.6.0 -source decoder.go -destination=mocks/mock_types.go -package=mocks
-
 type EpDecoder interface {
 	Decode(ip netip.Addr) *flow.Endpoint
 	IsEndpointOnLocalHost(ip string) bool

pkg/log/zap.go

@@ -3,17 +3,21 @@
 package log
 
 import (
+	"log/slog"
 	"net/http"
 	"os"
 	"runtime"
 	"time"
 
 	"github.com/Azure/azure-container-networking/zapai"
 	"github.com/go-chi/chi/middleware"
+	"github.com/go-logr/logr"
+	"github.com/go-logr/zapr"
 	logfmt "github.com/jsternberg/zap-logfmt"
 	"github.com/microsoft/ApplicationInsights-Go/appinsights"
 	"github.com/pkg/errors"
 	"go.uber.org/zap"
+	"go.uber.org/zap/exp/zapslog"
 	"go.uber.org/zap/zapcore"
 	"gopkg.in/natefinch/lumberjack.v2"
 )
@@ -46,6 +50,11 @@ func GetDefaultLogOpts() *LogOpts {
 }
 
 func Logger() *ZapLogger {
+	if global == nil {
+		// Auto-initialize with default options if not already set
+		// This provides a fallback for code that accesses Logger() before SetupZapLogger()
+		_, _ = SetupZapLogger(GetDefaultLogOpts())
+	}
 	return global
 }
 
@@ -202,3 +211,35 @@ func (lOpts *LogOpts) validate() {
 		}
 	}
 }
+
+// SlogHandler returns an slog.Handler backed by the global zap core.
+// All slog messages will flow through zap's pipeline (stdout + Application Insights).
+func SlogHandler() slog.Handler {
+	if global == nil {
+		return slog.NewTextHandler(os.Stdout, nil)
+	}
+	return zapslog.NewHandler(global.Core(), zapslog.WithCaller(true))
+}
+
+// SetDefaultSlog sets Go's global slog default to use the zap-backed handler.
+// After calling this, slog.Default() returns a logger that routes through zap.
+func SetDefaultSlog() {
+	slog.SetDefault(slog.New(SlogHandler()))
+}
+
+// SlogLogger returns a new *slog.Logger backed by the global zap core.
+func SlogLogger() *slog.Logger {
+	return slog.New(SlogHandler())
+}
+
+// LogrLogger returns a logr.Logger backed by the global zap logger.
+// This is useful for integrating with controller-runtime and other libraries
+// that use logr.Logger, ensuring consistent log format across the application.
+func LogrLogger() logr.Logger {
+	if global == nil {
+		// Fallback to a basic zap logger if global is not initialized
+		zapLogger, _ := zap.NewProduction()
+		return zapr.NewLogger(zapLogger)
+	}
+	return zapr.NewLogger(global.Logger)
+}

pkg/log/zap_test.go

@@ -3,12 +3,14 @@
 package log
 
 import (
+	"log/slog"
 	"os"
 	"path/filepath"
 	"strings"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 	"go.uber.org/zap"
 )
 
@@ -51,3 +53,67 @@ func TestLogFileRotation(t *testing.T) {
 	assert.NoError(t, err, "Test log file walk through failed with err")
 	assert.Equal(t, expectedReplicas, curReplicas, "Test log file replicas are not as expected on 2nd try")
 }
+
+func TestSlogHandler(t *testing.T) {
+	// Reset the global logger for this test
+	global = nil
+
+	_, err := SetupZapLogger(GetDefaultLogOpts())
+	require.NoError(t, err)
+
+	handler := SlogHandler()
+	require.NotNil(t, handler)
+
+	logger := slog.New(handler)
+	// Should not panic
+	logger.Info("test message from slog", "key", "value")
+
+	// SetDefaultSlog should make slog.Default() return zap-backed logger
+	SetDefaultSlog()
+	slog.Default().Info("default slog test", "source", "TestSlogHandler")
+
+	// SlogLogger should return a new logger
+	slogLogger := SlogLogger()
+	require.NotNil(t, slogLogger)
+	slogLogger.Info("from SlogLogger", "test", true)
+}
+
+func TestSlogHandlerFallback(t *testing.T) {
+	// Reset global to test fallback behavior
+	global = nil
+
+	// Without zap setup, SlogHandler should return a fallback text handler
+	handler := SlogHandler()
+	require.NotNil(t, handler)
+
+	// Should not panic even without zap being setup
+	logger := slog.New(handler)
+	logger.Info("fallback test message", "key", "value")
+}
+
+func TestLogrLogger(t *testing.T) {
+	// Reset the global logger for this test
+	global = nil
+
+	_, err := SetupZapLogger(GetDefaultLogOpts())
+	require.NoError(t, err)
+
+	logrLogger := LogrLogger()
+	require.NotNil(t, logrLogger)
+
+	// Should not panic and should log using the same format as Retina's zap logger
+	logrLogger.Info("test message from logr", "key", "value")
+	logrLogger.V(1).Info("debug message from logr", "level", 1)
+}
+
+func TestLogrLoggerFallback(t *testing.T) {
+	// Reset global to test fallback behavior
+	global = nil
+
+	// Without zap setup, LogrLogger should return a fallback logger
+	logrLogger := LogrLogger()
+	require.NotNil(t, logrLogger)
+
+	// Should not panic even without zap being setup
+	logrLogger.Info("fallback logr test message", "key", "value")
+}

pkg/metrics/metrics.go

@@ -3,16 +3,17 @@
 package metrics
 
 import (
+	"log/slog"
+
 	"github.com/microsoft/retina/pkg/exporter"
-	"github.com/microsoft/retina/pkg/log"
 	"github.com/microsoft/retina/pkg/utils"
 	"github.com/prometheus/client_golang/prometheus"
 	dto "github.com/prometheus/client_model/go"
 )
 
 // Initiates and creates the common metrics
-func InitializeMetrics() {
-	metricsLogger = log.Logger().Named("metrics")
+func InitializeMetrics(logger *slog.Logger) {
+	metricsLogger = logger.With("module", "metrics")
 
 	if isInitialized {
 		metricsLogger.Warn("Metrics already initialized. Exiting.")

pkg/metrics/metrics_test.go

@@ -4,6 +4,7 @@
 package metrics
 
 import (
+	"log/slog"
 	"testing"
 
 	"github.com/microsoft/retina/pkg/log"
@@ -12,7 +13,7 @@ import (
 func TestInitialization_FirstInit(t *testing.T) {
 	log.SetupZapLogger(log.GetDefaultLogOpts())
 
-	InitializeMetrics()
+	InitializeMetrics(slog.Default())
 
 	//  All metrics should be initialized.
 	objs := []interface{}{DropPacketsGauge, DropBytesGauge, ForwardBytesGauge, ForwardPacketsGauge, NodeConnectivityStatusGauge, NodeConnectivityLatencyGauge, PluginManagerFailedToReconcileCounter}
@@ -31,7 +32,7 @@ func TestInitialization_MultipleInit(t *testing.T) {
 	}()
 	log.SetupZapLogger(log.GetDefaultLogOpts())
 
-	InitializeMetrics()
+	InitializeMetrics(slog.Default())
 	// Should not panic when reinitializing.
-	InitializeMetrics()
+	InitializeMetrics(slog.Default())
 }

pkg/metrics/types.go

@@ -3,9 +3,9 @@
 package metrics
 
 import (
-	"github.com/microsoft/retina/pkg/log"
+	"log/slog"
+
 	"github.com/prometheus/client_golang/prometheus"
-	"go.uber.org/zap"
 )
 
 const (
@@ -87,7 +87,7 @@ var (
 	// Interface Stats
 	InterfaceStatsGauge GaugeVec
 
-	metricsLogger *log.ZapLogger
+	metricsLogger *slog.Logger
 
 	// Control Plane Metrics
 	PluginManagerFailedToReconcileCounter CounterVec
@@ -119,7 +119,9 @@ func ToPrometheusType(metric interface{}) prometheus.Collector {
 	case CounterVec:
 		return m.(*prometheus.CounterVec)
 	default:
-		metricsLogger.Error("error converting unknown metric type", zap.Any("metric", m))
+		if metricsLogger != nil {
+			metricsLogger.Error("error converting unknown metric type", slog.Any("metric", m))
+		}
 		return nil
 	}
 }

pkg/plugin/common/common_linux.go

@@ -22,18 +22,7 @@ import (
 	"golang.org/x/sys/unix"
 )
 
-//go:generate go run go.uber.org/mock/mockgen@v0.4.0 -destination=mocks/mock_types.go -package=mocks . ITracer
-
-// Interface for IG tracers.
-// Ref: https://pkg.go.dev/github.com/inspektor-gadget/inspektor-gadget@v0.18.1/pkg/gadgets/trace/dns/tracer#Tracer
-type ITracer interface {
-	SetEventHandler(interface{})
-	Attach(pid uint32) error
-	Detach(pid uint32) error
-	Close()
-}
-
-// Interface for IG event handlers. Maps to cilum Flow.
+// ProtocolToFlow converts a protocol string to the corresponding Unix protocol number.
 func ProtocolToFlow(protocol string) int {
 	switch protocol {
 	case "tcp":