Logging: expose log level through log wrappers

pkg/util/log/slogadapter_test.go

@@ -8,6 +8,7 @@ import (
 	"log/slog"
 	"testing"
 
+	"github.com/go-kit/log"
 	"github.com/go-kit/log/level"
 	dslog "github.com/grafana/dskit/log"
 	"github.com/stretchr/testify/assert"
@@ -90,3 +91,29 @@ func TestSlogFromGoKit(t *testing.T) {
 		}
 	})
 }
+
+func BenchmarkSlogFromGoKit(b *testing.B) {
+	// Set up a logger with a stack of wrappers, similar to what tsdb gets.
+	var lvl dslog.Level
+	lvl.Set("info")
+	var logger log.Logger
+	logger = noopLogger{}
+	logger = newFilter(logger, lvl)
+	logger = WithUserID("userID", logger)
+
+	sl := SlogFromGoKit(logger)
+	b.Run("log", func(b *testing.B) {
+		for i := 0; i < b.N; i++ {
+			sl.Info("msg", "foo", "bar", "more", "data")
+		}
+	})
+	b.Run("debuglog", func(b *testing.B) {
+		for i := 0; i < b.N; i++ {
+			sl.Debug("msg", "foo", "bar", "more", "data")
+		}
+	})
+}
+
+type noopLogger struct{}
+
+func (noopLogger) Log(...interface{}) error { return nil }

pkg/util/log/wrappers.go

@@ -13,24 +13,42 @@ import (
 	"github.com/grafana/dskit/tracing"
 )
 
+// levelWrapper implements leveledLogger and log.Logger.
+type levelWrapper struct {
+	lvl        logLevel
+	log.Logger // Calls to Log() will fall through to here.
+}
+
+func wrap(original, logger log.Logger) log.Logger {
+	lvl := debugLevel // default if unknown
+	if x, ok := original.(leveledLogger); ok {
+		lvl = x.level()
+	}
+	return levelWrapper{lvl: lvl, Logger: logger}
+}
+
+func (w levelWrapper) level() logLevel {
+	return w.lvl
+}
+
 // WithUserID returns a Logger that has information about the current user in
 // its details.
 func WithUserID(userID string, l log.Logger) log.Logger {
 	// See note in WithContext.
-	return log.With(l, "user", userID)
+	return wrap(l, log.With(l, "user", userID))
 }
 
 // WithUserIDs returns a Logger that has information about the current user or
 // users (separated by "|") in its details.
 func WithUserIDs(userIDs []string, l log.Logger) log.Logger {
-	return log.With(l, "user", tenant.JoinTenantIDs(userIDs))
+	return wrap(l, log.With(l, "user", tenant.JoinTenantIDs(userIDs)))
 }
 
 // WithTraceID returns a Logger that has information about the traceID in
 // its details.
 func WithTraceID(traceID string, l log.Logger) log.Logger {
 	// See note in WithContext.
-	return log.With(l, "traceID", traceID)
+	return wrap(l, log.With(l, "traceID", traceID))
 }
 
 // WithContext returns a Logger that has information about the current user or users
@@ -60,5 +78,5 @@ func WithContext(ctx context.Context, l log.Logger) log.Logger {
 // WithSourceIPs returns a Logger that has information about the source IPs in
 // its details.
 func WithSourceIPs(sourceIPs string, l log.Logger) log.Logger {
-	return log.With(l, "sourceIPs", sourceIPs)
+	return wrap(l, log.With(l, "sourceIPs", sourceIPs))
 }