```

feat(logger): add maxCount configuration option for file appender

Add support for maxCount parameter in file appender configuration.
The maxCount option allows users to specify the maximum number of
backup files to keep when log rotation is enabled.

The new configuration option defaults to 1 if not specified in the
appender options and is passed to the FileAppender struct during
initialization.
```

Co-authored-by: Copilot <copilot@github.com>

file.go

@@ -4,31 +4,37 @@ import (
 	"os"
 	"path/filepath"
 	"regexp"
+	"sort"
 	"strconv"
+	"strings"
+	"sync"
 	"time"
 )
 
 // FileAppender implements the LoggerAppender interface for file output.
 // It supports log rotation based on file size and age.
 // Example:
-//  appender := &FileAppender{
-//    formatter: NewSimpleFormatter(),
-//    filePath: "app.log",
-//    EnableRolling: true,
-//    MaxSize: 1024 * 1024 * 10, // 10MB
-//  }
-//  appender.Append(event)
-//  appender.Close()
+//
+//	appender := &FileAppender{
+//	  formatter: NewSimpleFormatter(),
+//	  filePath: "app.log",
+//	  EnableRolling: true,
+//	  MaxSize: 1024 * 1024 * 10, // 10MB
+//	}
+//	appender.Append(event)
+//	appender.Close()
 type FileAppender struct {
 	formatter LogFormatter
 	filePath  string
 	lchan     chan LogEvent
 	file      *os.File
 	stopChan  chan struct{}
+	mu        sync.Mutex
 	// 新增滚动相关字段
 	EnableRolling   bool
 	MaxSize         int64 // 文件最大大小(字节)
 	MaxAge          int64 // 文件最大时间(秒)
+	MaxCount        int   // 最大文件数量
 	currentFileSize int64 // 当前文件大小
 	createdAt       int64 // 文件创建时间戳
 }
@@ -63,57 +69,98 @@ func (f *FileAppender) start() {
 	}
 
 	go func() {
-		defer f.file.Close()
 		for {
 			select {
 			case <-f.stopChan:
+				f.mu.Lock()
+				if f.file != nil {
+					f.file.Close()
+				}
+				f.mu.Unlock()
 				return
 			case logEvent := <-f.lchan:
+				f.mu.Lock()
 				// 检查日志滚动
 				if f.EnableRolling {
-					f.checkAndRoll(logEvent)
+					if f.checkAndRoll(logEvent) {
+						f.mu.Unlock()
+						continue
+					}
 				}
 				logMsg := f.formatter(logEvent)
-				f.file.WriteString(logMsg)
+				n, err := f.file.WriteString(logMsg)
+				if err == nil {
+					f.currentFileSize += int64(n)
+				}
+				f.mu.Unlock()
 			}
 		}
 	}()
 }
 
-// 新增日志滚动方法
-func (f *FileAppender) checkAndRoll(logEvent LogEvent) {
+// 新增日志滚动方法，返回是否进行了滚动
+func (f *FileAppender) checkAndRoll(logEvent LogEvent) bool {
 	// 按大小滚动
 	if f.MaxSize > 0 && f.currentFileSize >= f.MaxSize {
 		f.rollFile(logEvent)
-		return
+		return true
 	}
 
 	// 按时间滚动
 	if f.MaxAge > 0 && time.Now().Unix()-f.createdAt >= f.MaxAge {
 		f.rollFile(logEvent)
+		return true
 	}
+	return false
 }
 
 // 日志文件滚动
 func (f *FileAppender) rollFile(logEvent LogEvent) {
 	// 关闭当前文件
-	f.file.Close()
+	if f.file != nil {
+		f.file.Close()
+	}
 
 	// 重命名旧文件
 	timestamp := time.Now().Format("20060102150405")
 	newPath := f.filePath + "." + timestamp
-	os.Rename(f.filePath, newPath)
+	if err := os.Rename(f.filePath, newPath); err != nil {
+		// 重命名失败，直接创建新文件
+		f.file, _ = os.OpenFile(f.filePath, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0644)
+		return
+	}
 
 	// 创建新文件
-	f.file, _ = os.OpenFile(f.filePath, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0644)
+	var err error
+	f.file, err = os.OpenFile(f.filePath, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0644)
+	if err != nil {
+		return
+	}
 
 	// 重置状态
 	f.currentFileSize = 0
 	f.createdAt = time.Now().Unix()
 
 	// 重新写入当前日志
-	logMsg := format(logEvent)
-	f.file.WriteString(logMsg)
+	logMsg := f.formatter(logEvent)
+	if _, err := f.file.WriteString(logMsg); err == nil {
+		f.currentFileSize += int64(len(logMsg))
+	}
+
+	// 清理超过MaxCount的旧文件
+	if f.MaxCount > 0 {
+		logDir := filepath.Dir(newPath)
+		logFileBase := filepath.Base(f.filePath)
+		files, _ := filepath.Glob(logDir + "/" + logFileBase + ".*")
+		if len(files) > f.MaxCount {
+			sort.Slice(files, func(i, j int) bool {
+				return files[i] < files[j]
+			})
+			for i := 0; i < len(files)-f.MaxCount; i++ {
+				os.Remove(files[i])
+			}
+		}
+	}
 }
 
 func (f *FileAppender) Append(logEvent LogEvent) {
@@ -122,9 +169,7 @@ func (f *FileAppender) Append(logEvent LogEvent) {
 }
 
 func makeFileAppender(appenderConfig LogAppenderConfig) *LoggerAppender {
-	var logfile interface{}
-	var ok bool
-	logfile, ok = appenderConfig.Options["file"]
+	logfile, ok := appenderConfig.Options["file"]
 	if !ok {
 		logfile = "default.log"
 	}
@@ -167,16 +212,16 @@ func makeFileAppender(appenderConfig LogAppenderConfig) *LoggerAppender {
 		re := regexp.MustCompile(`^\d+[hd]?$`)
 		if re.MatchString(ageStr) {
 			// 提取数字部分和单位
-			numStr := ""
+			var numStr strings.Builder
 			unit := ""
 			for _, c := range ageStr {
 				if c >= '0' && c <= '9' {
-					numStr += string(c)
+					numStr.WriteRune(c)
 				} else {
 					unit = string(c)
 				}
 			}
-			num, _ := strconv.ParseInt(numStr, 10, 64)
+			num, _ := strconv.ParseInt(numStr.String(), 10, 64)
 			switch unit {
 			case "h":
 				maxAge = num * 3600 // 小时转秒
@@ -187,6 +232,10 @@ func makeFileAppender(appenderConfig LogAppenderConfig) *LoggerAppender {
 	} else if ageInt, ok := appenderConfig.Options["maxAge"].(int64); ok {
 		maxAge = ageInt
 	}
+	maxCount := int(1)
+	if count, ok := appenderConfig.Options["maxCount"].(int); ok {
+		maxCount = count
+	}
 
 	var ret LoggerAppender = &FileAppender{
 		formatter:     SelectFormatter(appenderConfig.Formatter),
@@ -194,6 +243,7 @@ func makeFileAppender(appenderConfig LogAppenderConfig) *LoggerAppender {
 		EnableRolling: rollingEnabled,
 		MaxSize:       maxSize,
 		MaxAge:        maxAge,
+		MaxCount:      maxCount,
 	}
 
 	ret.(*FileAppender).start()

format.go

@@ -23,16 +23,17 @@ const logTemplate = "[%s] %s : %s - %s\n"
 // Template: "[timestamp] level : category - data"
 func format(logEvent LogEvent) string {
 	data := logEvent.Ts.Format("2006-01-02 15:04:05")
-	msg := ""
-	firstMsg := logEvent.Data[0]
-	if isFormatString(firstMsg) {
-		msg = fmt.Sprintf(firstMsg.(string), logEvent.Data[1:]...)
-	} else {
-		msg = sprint(logEvent.Data)
+	var msg string
+	if len(logEvent.Data) > 0 {
+		firstMsg := logEvent.Data[0]
+		if isFormatString(firstMsg) {
+			msg = fmt.Sprintf(firstMsg.(string), logEvent.Data[1:]...)
+		} else {
+			msg = sprint(logEvent.Data)
+		}
 	}
 
-	ret := fmt.Sprintf(logTemplate, data, logEvent.Category, getLogLevelStr(logEvent.Level), msg)
-	return ret
+	return fmt.Sprintf(logTemplate, data, logEvent.Category, getLogLevelStr(logEvent.Level), msg)
 }
 
 func getLogLevelStr(level int) string {
@@ -44,34 +45,35 @@ func getLogLevelStr(level int) string {
 	return "Unknown"
 }
 
-func isFormatString(f interface{}) bool {
+func isFormatString(f any) bool {
 	s, ok := f.(string)
 	if !ok {
 		return false
 	}
-	// 尝试使用空接口来格式化字符串
-	m := fmt.Sprintf(s, []interface{}{}...)
-	return strings.Contains(m, "MISSING")
+	// 检查是否包含常见格式化动词
+	return strings.Contains(s, "%s") || strings.Contains(s, "%d") ||
+		strings.Contains(s, "%v") || strings.Contains(s, "%f") ||
+		strings.Contains(s, "%x") || strings.Contains(s, "%t") ||
+		strings.Contains(s, "%c") || strings.Contains(s, "%b") ||
+		strings.Contains(s, "%e") || strings.Contains(s, "%g")
 }
 
-func sprint(s []interface{}) string {
-	str := make([]any, len(s))
+func sprint(s []any) string {
+	var b strings.Builder
 	for i, v := range s {
 		if i > 0 {
-			str[i] = fmt.Sprintf(" %v", v)
-		} else {
-			str[i] = fmt.Sprintf("%v", v)
+			b.WriteString(" ")
 		}
+		fmt.Fprintf(&b, "%v", v)
 	}
-	return fmt.Sprint(str...)
+	return b.String()
 }
 
 func jsonFormatter(logEvent LogEvent) string {
-	_, err := json.Marshal(logEvent.Data)
+	d, err := json.Marshal(logEvent)
 	if err != nil {
-		logEvent.Data = []interface{}{fmt.Sprintf("%v", logEvent.Data)}
+		return fmt.Sprintf(`{"error":"%v"}`, logEvent.Data)
 	}
-	d, _ := json.Marshal(logEvent)
 	return string(d)
 }
 

main.go

@@ -4,6 +4,7 @@ package gologger
 
 import (
 	"strings"
+	"sync"
 	"time"
 )
 
@@ -27,6 +28,7 @@ var logLevelMap map[string]int = map[string]int{
 var loggerMap map[string]*Logger = map[string]*Logger{}
 var appenderFactoryMap map[string]func(LogAppenderConfig) *LoggerAppender = map[string]func(LogAppenderConfig) *LoggerAppender{}
 var appenders map[string]*LoggerAppender = map[string]*LoggerAppender{}
+var mu sync.RWMutex
 var loggerConfig LoggersConfig = LoggersConfig{
 	Appenders: map[string]LogAppenderConfig{
 		"console": {
@@ -124,19 +126,24 @@ func (l *Logger) Trace(msg ...interface{}) {
 	l.log(Trace, msg)
 }
 func GetLogger(name string) *Logger {
+	mu.RLock()
 	if logger, ok := loggerMap[name]; ok {
+		mu.RUnlock()
 		return logger
-	} else {
-		logConfig, ok := loggerConfig.Categories[name]
-		if ok {
-			return makeLogger(name, logConfig)
-		}
-		logConfig, ok = loggerConfig.Categories["default"]
-		l := makeLogger(name, logConfig)
-		l.category = name
-		loggerMap[name] = l
-		return l
 	}
+	mu.RUnlock()
+
+	logConfig, ok := loggerConfig.Categories[name]
+	if !ok {
+		logConfig = loggerConfig.Categories["default"]
+	}
+	l := makeLogger(name, logConfig)
+	l.category = name
+
+	mu.Lock()
+	loggerMap[name] = l
+	mu.Unlock()
+	return l
 }
 
 func makeLogger(name string, config LogConfig) *Logger {
@@ -158,14 +165,16 @@ func makeLogger(name string, config LogConfig) *Logger {
 
 func ReconfigLoggers(config LoggersConfig) {
 	validateConfig(config)
+
+	mu.Lock()
+	defer mu.Unlock()
+
 	loggerConfig = config
 	for name, appenderConfig := range loggerConfig.Appenders {
-		oldappender, ok := appenders[name]
-		if ok {
+		if oldappender, ok := appenders[name]; ok {
 			(*oldappender).Close()
 		}
-		appenderFactory, ok := appenderFactoryMap[appenderConfig.Type]
-		if ok {
+		if appenderFactory, ok := appenderFactoryMap[appenderConfig.Type]; ok {
 			appenders[name] = appenderFactory(appenderConfig)
 		} else {
 			appenders[name] = &consoleAppender
@@ -174,7 +183,7 @@ func ReconfigLoggers(config LoggersConfig) {
 	for name, logger := range loggerMap {
 		logConfig, ok := loggerConfig.Categories[name]
 		if !ok {
-			logConfig, _ = loggerConfig.Categories["default"]
+			logConfig = loggerConfig.Categories["default"]
 		}
 		logger.level = logLevelMap[strings.ToLower(logConfig.Level)]
 		if len(logConfig.Appenders) == 0 {