fix: renforcer corrélation A/B et sorties stdout/fichier

Co-authored-by: aider (openrouter/openai/gpt-5.3-codex) <aider@aider.chat>

internal/observability/logger.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"log"
 	"os"
+	"sort"
 	"strings"
 	"sync"
 )
@@ -52,10 +53,10 @@ func (l LogLevel) String() string {
 
 // Logger provides structured logging.
 type Logger struct {
-	mu      sync.Mutex
-	logger  *log.Logger
-	prefix  string
-	fields  map[string]any
+	mu       sync.RWMutex
+	logger   *log.Logger
+	prefix   string
+	fields   map[string]any
 	minLevel LogLevel
 }
 
@@ -88,30 +89,32 @@ func (l *Logger) SetLevel(level string) {
 
 // ShouldLog returns true if the given level should be logged.
 func (l *Logger) ShouldLog(level LogLevel) bool {
-	l.mu.Lock()
-	defer l.mu.Unlock()
+	l.mu.RLock()
+	defer l.mu.RUnlock()
 	return level >= l.minLevel
 }
 
 // WithFields returns a new logger with additional fields.
 func (l *Logger) WithFields(fields map[string]any) *Logger {
-	l.mu.Lock()
+	l.mu.RLock()
 	minLevel := l.minLevel
-	l.mu.Unlock()
-	
-	newLogger := &Logger{
+	prefix := l.prefix
+	existing := make(map[string]any, len(l.fields))
+	for k, v := range l.fields {
+		existing[k] = v
+	}
+	l.mu.RUnlock()
+
+	for k, v := range fields {
+		existing[k] = v
+	}
+
+	return &Logger{
 		logger:   l.logger,
-		prefix:   l.prefix,
-		fields:   make(map[string]any),
+		prefix:   prefix,
+		fields:   existing,
 		minLevel: minLevel,
 	}
-	for k, v := range l.fields {
-		newLogger.fields[k] = v
-	}
-	for k, v := range fields {
-		newLogger.fields[k] = v
-	}
-	return newLogger
 }
 
 // Info logs an info message.
@@ -119,8 +122,6 @@ func (l *Logger) Info(msg string) {
 	if !l.ShouldLog(INFO) {
 		return
 	}
-	l.mu.Lock()
-	defer l.mu.Unlock()
 	l.log("INFO", msg)
 }
 
@@ -129,8 +130,6 @@ func (l *Logger) Warn(msg string) {
 	if !l.ShouldLog(WARN) {
 		return
 	}
-	l.mu.Lock()
-	defer l.mu.Unlock()
 	l.log("WARN", msg)
 }
 
@@ -139,8 +138,6 @@ func (l *Logger) Error(msg string, err error) {
 	if !l.ShouldLog(ERROR) {
 		return
 	}
-	l.mu.Lock()
-	defer l.mu.Unlock()
 	if err != nil {
 		l.log("ERROR", msg+" "+err.Error())
 	} else {
@@ -153,8 +150,6 @@ func (l *Logger) Debug(msg string) {
 	if !l.ShouldLog(DEBUG) {
 		return
 	}
-	l.mu.Lock()
-	defer l.mu.Unlock()
 	l.log("DEBUG", msg)
 }
 
@@ -163,8 +158,6 @@ func (l *Logger) Debugf(msg string, args ...any) {
 	if !l.ShouldLog(DEBUG) {
 		return
 	}
-	l.mu.Lock()
-	defer l.mu.Unlock()
 	l.log("DEBUG", fmt.Sprintf(msg, args...))
 }
 
@@ -173,8 +166,6 @@ func (l *Logger) Warnf(msg string, args ...any) {
 	if !l.ShouldLog(WARN) {
 		return
 	}
-	l.mu.Lock()
-	defer l.mu.Unlock()
 	l.log("WARN", fmt.Sprintf(msg, args...))
 }
 
@@ -183,27 +174,42 @@ func (l *Logger) Infof(msg string, args ...any) {
 	if !l.ShouldLog(INFO) {
 		return
 	}
-	l.mu.Lock()
-	defer l.mu.Unlock()
 	l.log("INFO", fmt.Sprintf(msg, args...))
 }
 
 func (l *Logger) log(level, msg string) {
+	l.mu.RLock()
 	prefix := l.prefix
+	fields := make(map[string]any, len(l.fields))
+	for k, v := range l.fields {
+		fields[k] = v
+	}
+	l.mu.RUnlock()
+
+	var b strings.Builder
 	if prefix != "" {
-		prefix = "[" + prefix + "] "
+		b.WriteString("[")
+		b.WriteString(prefix)
+		b.WriteString("] ")
+	}
+	b.WriteString(level)
+	b.WriteString(" ")
+	b.WriteString(msg)
+
+	if len(fields) > 0 {
+		keys := make([]string, 0, len(fields))
+		for k := range fields {
+			keys = append(keys, k)
+		}
+		sort.Strings(keys)
+
+		for _, k := range keys {
+			b.WriteString(" ")
+			b.WriteString(k)
+			b.WriteString("=")
+			b.WriteString(fmt.Sprintf("%v", fields[k]))
+		}
 	}
 
-	l.logger.SetPrefix(prefix + level + " ")
-	
-	var args []any
-	for k, v := range l.fields {
-		args = append(args, k, v)
-	}
-	
-	if len(args) > 0 {
-		l.logger.Printf(msg+" %+v", args...)
-	} else {
-		l.logger.Print(msg)
-	}
+	l.logger.Print(b.String())
 }