feat: optimize for discard (#31)

hamba · Mar 16, 2022 · d51f019 · d51f019
1 parent 9d8f564
commit d51f019
Show file tree

Hide file tree

Showing 2 changed files with 38 additions and 24 deletions.
diff --git a/bench_test.go b/bench_test.go
@@ -1,7 +1,6 @@
 package logger_test
 
 import (
-	"io"
 	"os"
 	"testing"
 
@@ -10,7 +9,7 @@ import (
 )
 
 func BenchmarkLogger_Logfmt(b *testing.B) {
-	log := logger.New(io.Discard, logger.LogfmtFormat(), logger.Debug)
+	log := logger.New(discard{}, logger.LogfmtFormat(), logger.Debug)
 
 	b.ReportAllocs()
 	b.ResetTimer()
@@ -22,7 +21,7 @@ func BenchmarkLogger_Logfmt(b *testing.B) {
 }
 
 func BenchmarkLogger_Json(b *testing.B) {
-	log := logger.New(io.Discard, logger.JSONFormat(), logger.Debug)
+	log := logger.New(discard{}, logger.JSONFormat(), logger.Debug)
 
 	b.ReportAllocs()
 	b.ResetTimer()
@@ -34,7 +33,7 @@ func BenchmarkLogger_Json(b *testing.B) {
 }
 
 func BenchmarkLogger_LogfmtWriter(b *testing.B) {
-	log := logger.New(io.Discard, logger.LogfmtFormat(), logger.Debug)
+	log := logger.New(discard{}, logger.LogfmtFormat(), logger.Debug)
 	w := log.Writer(logger.Info)
 
 	p := []byte("some message")
@@ -49,7 +48,7 @@ func BenchmarkLogger_LogfmtWriter(b *testing.B) {
 }
 
 func BenchmarkLogger_LogfmtWithTS(b *testing.B) {
-	log := logger.New(io.Discard, logger.LogfmtFormat(), logger.Debug)
+	log := logger.New(discard{}, logger.LogfmtFormat(), logger.Debug)
 
 	cancel := log.WithTimestamp()
 	defer cancel()
@@ -64,7 +63,7 @@ func BenchmarkLogger_LogfmtWithTS(b *testing.B) {
 }
 
 func BenchmarkLogger_JsonWithTS(b *testing.B) {
-	log := logger.New(io.Discard, logger.JSONFormat(), logger.Debug)
+	log := logger.New(discard{}, logger.JSONFormat(), logger.Debug)
 
 	cancel := log.WithTimestamp()
 	defer cancel()
@@ -79,7 +78,7 @@ func BenchmarkLogger_JsonWithTS(b *testing.B) {
 }
 
 func BenchmarkLogger_LogfmtCtx(b *testing.B) {
-	log := logger.New(io.Discard, logger.LogfmtFormat(), logger.Debug).With(ctx.Str("_n", "bench"), ctx.Int("_p", 1))
+	log := logger.New(discard{}, logger.LogfmtFormat(), logger.Debug).With(ctx.Str("_n", "bench"), ctx.Int("_p", 1))
 
 	b.ReportAllocs()
 	b.ResetTimer()
@@ -91,7 +90,7 @@ func BenchmarkLogger_LogfmtCtx(b *testing.B) {
 }
 
 func BenchmarkLogger_JsonCtx(b *testing.B) {
-	log := logger.New(io.Discard, logger.JSONFormat(), logger.Debug).With(ctx.Str("_n", "bench"), ctx.Int("_p", 1))
+	log := logger.New(discard{}, logger.JSONFormat(), logger.Debug).With(ctx.Str("_n", "bench"), ctx.Int("_p", 1))
 
 	b.ReportAllocs()
 	b.ResetTimer()
@@ -103,7 +102,7 @@ func BenchmarkLogger_JsonCtx(b *testing.B) {
 }
 
 func BenchmarkLevelLogger_Logfmt(b *testing.B) {
-	log := logger.New(io.Discard, logger.LogfmtFormat(), logger.Debug).With(ctx.Str("_n", "bench"), ctx.Int("_p", os.Getpid()))
+	log := logger.New(discard{}, logger.LogfmtFormat(), logger.Debug).With(ctx.Str("_n", "bench"), ctx.Int("_p", os.Getpid()))
 
 	b.ResetTimer()
 	b.RunParallel(func(pb *testing.PB) {
@@ -117,7 +116,7 @@ func BenchmarkLevelLogger_Logfmt(b *testing.B) {
 }
 
 func BenchmarkLevelLogger_Json(b *testing.B) {
-	log := logger.New(io.Discard, logger.LogfmtFormat(), logger.Debug).With(ctx.Str("_n", "bench"), ctx.Int("_p", os.Getpid()))
+	log := logger.New(discard{}, logger.LogfmtFormat(), logger.Debug).With(ctx.Str("_n", "bench"), ctx.Int("_p", os.Getpid()))
 
 	b.ResetTimer()
 	b.RunParallel(func(pb *testing.PB) {
@@ -129,3 +128,9 @@ func BenchmarkLevelLogger_Json(b *testing.B) {
 		}
 	})
 }
+
+type discard struct{}
+
+func (discard) Write(p []byte) (int, error) {
+	return len(p), nil
+}
diff --git a/logger.go b/logger.go
@@ -62,19 +62,23 @@ type Field func(*Event)
 
 // Logger is a logger.
 type Logger struct {
-	w      io.Writer
-	fmtr   Formatter
-	timeFn func() int64
-	ctx    []byte
-	lvl    Level
+	w         io.Writer
+	isDiscard bool
+	fmtr      Formatter
+	timeFn    func() int64
+	ctx       []byte
+	lvl       Level
 }
 
 // New creates a new Logger.
 func New(w io.Writer, fmtr Formatter, lvl Level) *Logger {
+	isDiscard := w == io.Discard
+
 	return &Logger{
-		w:    w,
-		fmtr: fmtr,
-		lvl:  lvl,
+		w:         w,
+		isDiscard: isDiscard,
+		fmtr:      fmtr,
+		lvl:       lvl,
 	}
 }
 
@@ -128,11 +132,12 @@ func (l *Logger) With(ctx ...Field) *Logger {
 	copy(b, e.buf.Bytes())
 
 	return &Logger{
-		w:      l.w,
-		fmtr:   l.fmtr,
-		timeFn: l.timeFn,
-		lvl:    l.lvl,
-		ctx:    b,
+		w:         l.w,
+		isDiscard: l.isDiscard,
+		fmtr:      l.fmtr,
+		timeFn:    l.timeFn,
+		lvl:       l.lvl,
+		ctx:       b,
 	}
 }
 
@@ -172,6 +177,10 @@ func (fn writerFunc) Write(p []byte) (n int, err error) {
 func (l *Logger) Writer(lvl Level) io.Writer {
 	return writerFunc(func(p []byte) (n int, err error) {
 		n = len(p)
+		if l.isDiscard {
+			return n, nil
+		}
+
 		if n > 0 && p[n-1] == '\n' {
 			p = p[:n-1]
 		}
@@ -182,7 +191,7 @@ func (l *Logger) Writer(lvl Level) io.Writer {
 }
 
 func (l *Logger) write(msg string, lvl Level, ctx []Field) {
-	if lvl > l.lvl {
+	if l.isDiscard || lvl > l.lvl {
 		return
 	}