tests: adds logger benchmark. (#133)

* tests: adds logger benchmark.

* chore: adds early check for no logger.

.gitignore

@@ -9,3 +9,5 @@ __debug*
 .idea/
 
 build
+*.out
+coraza-caddy.test

logger.go

@@ -26,7 +26,24 @@ func newLogger(l *zap.Logger) debuglog.Logger {
 	}
 }
 
+func isZapNop(l *zap.Logger) bool {
+	// As per zap documentation when a logger is created with NewNop() it will have
+	// an invalid level
+	return l.Level() == zapcore.InvalidLevel
+}
+
 func (l *logger) WithOutput(w io.Writer) debuglog.Logger {
+	if w == io.Discard {
+		return &logger{
+			Logger: zap.NewNop(),
+			level:  l.level,
+		}
+	}
+
+	if isZapNop(l.Logger) {
+		return l
+	}
+
 	return &logger{
 		Logger: l.Logger.WithOptions(
 			zap.WrapCore(func(c zapcore.Core) zapcore.Core {
@@ -42,11 +59,17 @@ func (l *logger) WithOutput(w io.Writer) debuglog.Logger {
 }
 
 func (l *logger) WithLevel(level debuglog.Level) debuglog.Logger {
+	if level == debuglog.LevelNoLog {
+		return &logger{
+			Logger: zap.NewNop(),
+			level:  level,
+		}
+	}
 	return &logger{l.Logger, level}
 }
 
 func (l *logger) With(fields ...debuglog.ContextField) debuglog.Logger {
-	if len(fields) == 0 {
+	if len(fields) == 0 || isZapNop(l.Logger) {
 		return l
 	}
 

logger_test.go

@@ -0,0 +1,41 @@
+// Copyright 2024 The OWASP Coraza contributors
+// SPDX-License-Identifier: Apache-2.0
+
+package coraza
+
+import (
+	"os"
+	"testing"
+
+	"github.com/corazawaf/coraza/v3/debuglog"
+	"github.com/stretchr/testify/require"
+	"go.uber.org/zap"
+)
+
+func BenchmarkLogger(b *testing.B) {
+	f, err := os.CreateTemp(b.TempDir(), "test.log")
+	require.NoError(b, err)
+
+	cfg := zap.NewProductionConfig()
+	cfg.OutputPaths = []string{f.Name()}
+
+	l, err := cfg.Build()
+	require.NoError(b, err)
+
+	var (
+		l1, l2, l3  debuglog.Logger
+		debugLogger = newLogger(l)
+	)
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		l1 = debugLogger.With(debuglog.Str("key1", "value1"))
+		l1.Info().Msg("message1")
+
+		l2 = debugLogger.With(debuglog.Str("key2", "value2"), debuglog.Str("key3", "value3"))
+		l2.Info().Msg("message2&3")
+
+		l3 = debugLogger.With(debuglog.Str("key4", "value4"))
+		l3.Info().Msg("message4")
+	}
+}