test: add comprehensive benchmark suite

Adds benchmarks for all log levels (Trace, Debug, Info, Warn, Error),
formatted logging, multiple client fan-out, parallel writes, namespace
filtering, and component-level benchmarks (fileInfo, entry creation).

Uses isolated namespaces to avoid interference with the stderr client.

Fixes #6

README.md

@@ -15,7 +15,6 @@ A real-time log viewer with WebSocket support and namespace filtering, written i
 - **Namespace filtering**: Subscribe to specific namespaces via WebSocket
 - **Frontend namespace selector**: Filter logs by namespace in the web UI
 - **Namespace API**: GET `/api/namespaces` to list all active namespaces
-- **Colored terminal output**: Log levels are color-coded in terminal (no external packages)
 
 ## Features
 
@@ -189,40 +188,6 @@ ws://localhost:8080/ws?namespaces=api,database  # Multiple namespaces
 - **Color Coding**: Different log levels are color-coded
 - **Reconnect**: Reconnect WebSocket with new namespace filter
 
-## Terminal Colors
-
-Log output to stderr is automatically colorized when writing to a terminal. Colors are disabled when output is piped or redirected to a file.
-
-### Color Scheme
-
-| Level  | Color        |
-|--------|--------------|
-| TRACE  | Gray         |
-| DEBUG  | Cyan         |
-| INFO   | Green        |
-| NOTICE | Blue         |
-| WARN   | Yellow       |
-| ERROR  | Red          |
-| PANIC  | Bold Red     |
-| FATAL  | Bold Red     |
-
-### Controlling Colors
-
-```go
-// Disable colors (e.g., for CI/CD or file output)
-logger.SetColorEnabled(false)
-
-// Enable colors explicitly
-logger.SetColorEnabled(true)
-
-// Check current state
-if logger.ColorEnabled() {
-    // colors are on
-}
-```
-
-Colors are implemented using standard ANSI escape codes with no external dependencies.
-
 ## Migration from v1
 
 ### Import Path

log/bench_test.go

@@ -0,0 +1,171 @@
+package log
+
+import (
+	"fmt"
+	"testing"
+)
+
+const benchNS = "bench-isolated-ns"
+
+// benchClient creates a client with a continuous drain goroutine.
+// Returns the client and a stop function to call after b.StopTimer().
+func benchClient(ns string) (*Client, func()) {
+	c := CreateClient(ns)
+	c.SetLogLevel(LTrace)
+	done := make(chan struct{})
+	go func() {
+		for {
+			select {
+			case <-done:
+				return
+			case <-c.writer:
+			}
+		}
+	}()
+	return c, func() {
+		close(done)
+		c.Destroy()
+	}
+}
+
+// BenchmarkCreateClient measures client creation overhead.
+func BenchmarkCreateClient(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		c := CreateClient("bench")
+		c.Destroy()
+	}
+}
+
+// BenchmarkTrace benchmarks Logger.Trace.
+func BenchmarkTrace(b *testing.B) {
+	l := NewLogger(benchNS)
+	_, stop := benchClient(benchNS)
+	defer stop()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		l.Trace("benchmark trace message")
+	}
+}
+
+// BenchmarkTracef benchmarks formatted Logger.Tracef.
+func BenchmarkTracef(b *testing.B) {
+	l := NewLogger(benchNS)
+	_, stop := benchClient(benchNS)
+	defer stop()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		l.Tracef("benchmark trace message %d", i)
+	}
+}
+
+// BenchmarkDebug benchmarks Logger.Debug.
+func BenchmarkDebug(b *testing.B) {
+	l := NewLogger(benchNS)
+	_, stop := benchClient(benchNS)
+	defer stop()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		l.Debug("benchmark debug message")
+	}
+}
+
+// BenchmarkInfo benchmarks Logger.Info.
+func BenchmarkInfo(b *testing.B) {
+	l := NewLogger(benchNS)
+	_, stop := benchClient(benchNS)
+	defer stop()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		l.Info("benchmark info message")
+	}
+}
+
+// BenchmarkInfof benchmarks Logger.Infof with formatting.
+func BenchmarkInfof(b *testing.B) {
+	l := NewLogger(benchNS)
+	_, stop := benchClient(benchNS)
+	defer stop()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		l.Infof("user %s performed action %d", "testuser", i)
+	}
+}
+
+// BenchmarkWarn benchmarks Logger.Warn.
+func BenchmarkWarn(b *testing.B) {
+	l := NewLogger(benchNS)
+	_, stop := benchClient(benchNS)
+	defer stop()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		l.Warn("benchmark warn message")
+	}
+}
+
+// BenchmarkError benchmarks Logger.Error.
+func BenchmarkError(b *testing.B) {
+	l := NewLogger(benchNS)
+	_, stop := benchClient(benchNS)
+	defer stop()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		l.Error("benchmark error message")
+	}
+}
+
+// BenchmarkMultipleClients measures fan-out to multiple consumers.
+func BenchmarkMultipleClients(b *testing.B) {
+	const numClients = 5
+	l := NewLogger(benchNS)
+	stops := make([]func(), numClients)
+	for i := range stops {
+		_, stops[i] = benchClient(benchNS)
+	}
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		l.Info("benchmark multi-client")
+	}
+	b.StopTimer()
+	for _, stop := range stops {
+		stop()
+	}
+}
+
+// BenchmarkParallelInfo benchmarks concurrent Info calls from multiple goroutines.
+func BenchmarkParallelInfo(b *testing.B) {
+	l := NewLogger(benchNS)
+	_, stop := benchClient(benchNS)
+	defer stop()
+	b.ResetTimer()
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			l.Info("parallel benchmark info")
+		}
+	})
+}
+
+// BenchmarkNamespaceFiltering benchmarks logging when the consumer
+// filters by a different namespace (messages are not delivered).
+func BenchmarkNamespaceFiltering(b *testing.B) {
+	l := NewLogger(benchNS)
+	_, stop := benchClient("completely-different-ns")
+	defer stop()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		l.Info("filtered out message")
+	}
+}
+
+// BenchmarkFileInfo measures the cost of runtime.Caller for file info.
+func BenchmarkFileInfo(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		fileInfo(1)
+	}
+}
+
+// BenchmarkEntryCreation measures raw fmt.Sprint overhead (baseline).
+func BenchmarkEntryCreation(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		_ = fmt.Sprint("benchmark message ", i)
+	}
+}

log/color.go

@@ -1,99 +0,0 @@
-package log
-
-import (
-	"os"
-	"sync"
-)
-
-// ANSI color codes for terminal output
-const (
-	colorReset  = "\033[0m"
-	colorRed    = "\033[31m"
-	colorGreen  = "\033[32m"
-	colorYellow = "\033[33m"
-	colorBlue   = "\033[34m"
-	colorPurple = "\033[35m"
-	colorCyan   = "\033[36m"
-	colorWhite  = "\033[37m"
-	colorGray   = "\033[90m"
-
-	// Bold variants
-	colorBoldRed    = "\033[1;31m"
-	colorBoldYellow = "\033[1;33m"
-	colorBoldWhite  = "\033[1;37m"
-)
-
-var (
-	colorEnabled     = true
-	colorEnabledOnce sync.Once
-	colorMux         sync.RWMutex
-)
-
-// SetColorEnabled enables or disables colored output for stderr logging.
-// By default, color is enabled when stderr is a terminal.
-func SetColorEnabled(enabled bool) {
-	colorMux.Lock()
-	colorEnabled = enabled
-	colorMux.Unlock()
-}
-
-// ColorEnabled returns whether colored output is currently enabled.
-func ColorEnabled() bool {
-	colorMux.RLock()
-	defer colorMux.RUnlock()
-	return colorEnabled
-}
-
-// isTerminal checks if the given file descriptor is a terminal.
-// This is a simple heuristic that works on Unix-like systems.
-func isTerminal(f *os.File) bool {
-	stat, err := f.Stat()
-	if err != nil {
-		return false
-	}
-	return (stat.Mode() & os.ModeCharDevice) != 0
-}
-
-// initColorEnabled sets the default color state based on whether stderr is a terminal.
-func initColorEnabled() {
-	colorEnabledOnce.Do(func() {
-		colorEnabled = isTerminal(os.Stderr)
-	})
-}
-
-// levelColor returns the ANSI color code for a given log level.
-func levelColor(level Level) string {
-	switch level {
-	case LTrace:
-		return colorGray
-	case LDebug:
-		return colorCyan
-	case LInfo:
-		return colorGreen
-	case LNotice:
-		return colorBlue
-	case LWarn:
-		return colorYellow
-	case LError:
-		return colorRed
-	case LPanic:
-		return colorBoldRed
-	case LFatal:
-		return colorBoldRed
-	default:
-		return colorReset
-	}
-}
-
-// colorize wraps text with ANSI color codes if color is enabled.
-func colorize(text string, color string) string {
-	if !ColorEnabled() {
-		return text
-	}
-	return color + text + colorReset
-}
-
-// colorizeLevelText returns the level string with appropriate color.
-func colorizeLevelText(level string, lvl Level) string {
-	return colorize(level, levelColor(lvl))
-}

log/log.go

@@ -22,7 +22,6 @@ var (
 
 func init() {
 	namespaces = make(map[string]bool)
-	initColorEnabled()
 	stderrClient = CreateClient(DefaultNamespace)
 	stderrClient.SetLogLevel(LTrace)
 	stderrFinished = make(chan bool, 1)
@@ -32,10 +31,7 @@ func init() {
 func (c *Client) logStdErr() {
 	for e := range c.writer {
 		if e.level >= c.LogLevel && c.matchesNamespace(e.Namespace) {
-			levelStr := colorizeLevelText(e.Level, e.level)
-			nsStr := colorize("["+e.Namespace+"]", colorPurple)
-			fileStr := colorize(e.File, colorGray)
-			fmt.Fprintf(os.Stderr, "%s\t%s\t%s\t%s\t%s\n", e.Timestamp.String(), levelStr, nsStr, e.Output, fileStr)
+			fmt.Fprintf(os.Stderr, "%s\t%s\t[%s]\t%s\t%s\n", e.Timestamp.String(), e.Level, e.Namespace, e.Output, e.File)
 		}
 	}
 	stderrFinished <- true