Add slogAdapter

Signed-off-by: SungJin1212 <[email protected]>

go.mod

@@ -81,6 +81,7 @@ require (
 	github.com/cespare/xxhash/v2 v2.3.0
 	github.com/google/go-cmp v0.6.0
 	github.com/sercand/kuberesolver/v5 v5.1.1
+	github.com/tjhop/slog-gokit v0.1.2
 	go.opentelemetry.io/collector/pdata v1.21.0
 	golang.org/x/exp v0.0.0-20240613232115-7f521ea00fb8
 	google.golang.org/protobuf v1.35.2

go.sum

@@ -1667,6 +1667,8 @@ github.com/thanos-io/promql-engine v0.0.0-20241203103240-2f49f80c7c68 h1:cChM/Fb
 github.com/thanos-io/promql-engine v0.0.0-20241203103240-2f49f80c7c68/go.mod h1:wx0JlRZtsB2S10JYUgeg5GqLfMxw31SzArP+28yyE00=
 github.com/thanos-io/thanos v0.37.1 h1:PuTMql3S/i5UWlBT0WbCDwwL6Kc6Jf7DLHt2rdj4ivY=
 github.com/thanos-io/thanos v0.37.1/go.mod h1:5Ni7Uc1Bc8UCGOYmZ/2f/LVvDkZKNDdqDJZqjDFG+rI=
+github.com/tjhop/slog-gokit v0.1.2 h1:pmQI4SvU9h4gA0vIQsdhJQSqQg4mOmsPykG2/PM3j1I=
+github.com/tjhop/slog-gokit v0.1.2/go.mod h1:8fhlcp8C8ELbg3GCyKv06tgt4B5sDq2P1r2DQAu1HuM=
 github.com/tv42/httpunix v0.0.0-20150427012821-b75d8614f926/go.mod h1:9ESjWnEqriFuLhtthL60Sar/7RFoluCcXsuvEwTV5KM=
 github.com/uber/jaeger-client-go v2.30.0+incompatible h1:D6wyKGCecFaSRUpo8lCVbaOOb6ThwMmTEbhRwtKR97o=
 github.com/uber/jaeger-client-go v2.30.0+incompatible/go.mod h1:WVhlPFC8FDjOFMMWRy2pZqQJSXxYSwNYOkTr/Z6d3Kk=

pkg/util/log/log.go

@@ -62,7 +62,8 @@ func InitLogger(cfg *server.Config) {
 
 // PrometheusLogger exposes Prometheus counters for each of go-kit's log levels.
 type PrometheusLogger struct {
-	logger log.Logger
+	logger   log.Logger
+	logLevel logging.Level
 }
 
 // NewPrometheusLogger creates a new instance of PrometheusLogger which exposes
@@ -92,7 +93,8 @@ func newPrometheusLoggerFrom(logger log.Logger, logLevel logging.Level, keyvals
 		logMessages.WithLabelValues(level.String())
 	}
 	return &PrometheusLogger{
-		logger: logger,
+		logger:   logger,
+		logLevel: logLevel,
 	}
 }
 

pkg/util/log/slog_adapter.go

@@ -0,0 +1,30 @@
+package log
+
+import (
+	"log/slog"
+
+	"github.com/go-kit/log"
+	sloggk "github.com/tjhop/slog-gokit"
+)
+
+// GoKitLogToSlog convert go-kit/log to slog
+// usage: logutil.GoKitLogToSlog(gokitLogger)
+func GoKitLogToSlog(logger log.Logger) *slog.Logger {
+	levelVar := slog.LevelVar{}
+	promLogger, ok := logger.(*PrometheusLogger)
+	if !ok {
+		levelVar.Set(slog.LevelDebug)
+	} else {
+		switch promLogger.logLevel.String() {
+		case "debug":
+			levelVar.Set(slog.LevelDebug)
+		case "info":
+			levelVar.Set(slog.LevelInfo)
+		case "warn":
+			levelVar.Set(slog.LevelWarn)
+		case "error":
+			levelVar.Set(slog.LevelError)
+		}
+	}
+	return slog.New(sloggk.NewGoKitHandler(logger, &levelVar))
+}

pkg/util/log/slog_adapter_test.go

@@ -0,0 +1,33 @@
+package log
+
+import (
+	"context"
+	"log/slog"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"github.com/weaveworks/common/server"
+)
+
+func Test_SlogAdapter_LogLevel(t *testing.T) {
+	ctx := context.Background()
+	logLevels := []string{"debug", "info", "warn", "error"}
+	slogLevels := []slog.Level{slog.LevelDebug, slog.LevelInfo, slog.LevelWarn, slog.LevelError}
+
+	for i, lv := range logLevels {
+		cfg := &server.Config{}
+		require.NoError(t, cfg.LogLevel.Set(lv))
+		InitLogger(cfg)
+
+		slog := GoKitLogToSlog(Logger)
+		for j, slogLv := range slogLevels {
+			if i <= j {
+				t.Logf("[go-kit log level: %v, slog level: %v] slog should be enabled", lv, slogLv)
+				require.True(t, slog.Enabled(ctx, slogLv))
+			} else {
+				t.Logf("[go-kit log level: %v, slog level: %v] slog should be disabled", lv, slogLv)
+				require.False(t, slog.Enabled(ctx, slogLv))
+			}
+		}
+	}
+}