Go使用自带的slog+lumberjack实现日志的封装

v2版本 go get github.com/natefinch/lumberjack

package mainimport ("context""io""log/slog""os""path/filepath""sync""github.com/natefinch/lumberjack"
)// 【以下 LeveledHandler 结构体和方法与 v3 版本完全一致，省略（直接复制上面的）】
// （注：为节省篇幅，这里省略重复代码，实际使用时需完整复制）
type LeveledHandler struct {handlers    map[slog.Level]slog.HandlerrootHandler slog.Handlermu          sync.RWMutex
}func NewLeveledHandler(rootHandler slog.Handler) *LeveledHandler {return &LeveledHandler{handlers:    make(map[slog.Level]slog.Handler),rootHandler: rootHandler,}
}func (lh *LeveledHandler) RegisterHandler(level slog.Level, h slog.Handler) {lh.mu.Lock()defer lh.mu.Unlock()lh.handlers[level] = h
}func (lh *LeveledHandler) Enabled(ctx context.Context, level slog.Level) bool {lh.mu.RLock()defer lh.mu.RUnlock()if h, ok := lh.handlers[level]; ok {return h.Enabled(ctx, level)}return lh.rootHandler.Enabled(ctx, level)
}func (lh *LeveledHandler) Handle(ctx context.Context, r slog.Record) error {lh.mu.RLock()defer lh.mu.RUnlock()if h, ok := lh.handlers[r.Level]; ok {return h.Handle(ctx, r)}return lh.rootHandler.Handle(ctx, r)
}func (lh *LeveledHandler) WithAttrs(attrs []slog.Attr) slog.Handler {lh.mu.RLock()defer lh.mu.RUnlock()newHandlers := make(map[slog.Level]slog.Handler, len(lh.handlers))for level, h := range lh.handlers {newHandlers[level] = h.WithAttrs(attrs)}return &LeveledHandler{handlers:    newHandlers,rootHandler: lh.rootHandler.WithAttrs(attrs),}
}func (lh *LeveledHandler) WithGroup(name string) slog.Handler {lh.mu.RLock()defer lh.mu.RUnlock()newHandlers := make(map[slog.Level]slog.Handler, len(lh.handlers))for level, h := range lh.handlers {newHandlers[level] = h.WithGroup(name)}return &LeveledHandler{handlers:    newHandlers,rootHandler: lh.rootHandler.WithGroup(name),}
}// NewRotateWriter 创建带轮转功能的 Writer（v2 版本）
func NewRotateWriter(logPath string, maxSize, maxBackups, maxAge int, compress bool) io.Writer {if err := os.MkdirAll(filepath.Dir(logPath), 0755); err != nil {slog.Error("创建日志目录失败", slog.String("path", logPath), slog.Any("err", err))return os.Stderr}// v2 版本：同样是 &lumberjack.Logger{}，但 Compress 字段是 v3 新增的，v2 需删除return &lumberjack.Logger{Filename:   logPath,MaxSize:    maxSize,MaxBackups: maxBackups,MaxAge:     maxAge,LocalTime:  true,Compress:   false, //压缩}
}// InitSlog 和 main 函数与 v3 版本完全一致，直接复制即可
func InitSlog() {debugWriter := NewRotateWriter("./logs/debug.log", 1, 10, 7, true)infoWriter := NewRotateWriter("./logs/info.log", 1, 10, 7, true)warnWriter := NewRotateWriter("./logs/warn.log", 1, 10, 7, true)errorWriter := NewRotateWriter("./logs/error.log", 1, 10, 7, true)debugHandler := slog.NewJSONHandler(debugWriter, &slog.HandlerOptions{Level: slog.LevelDebug})infoHandler := slog.NewJSONHandler(infoWriter, &slog.HandlerOptions{Level: slog.LevelInfo})warnHandler := slog.NewJSONHandler(warnWriter, &slog.HandlerOptions{Level: slog.LevelWarn})errorHandler := slog.NewJSONHandler(errorWriter, &slog.HandlerOptions{Level: slog.LevelError})consoleHandler := slog.NewTextHandler(os.Stdout, &slog.HandlerOptions{Level: slog.LevelDebug})leveledHandler := NewLeveledHandler(consoleHandler)leveledHandler.RegisterHandler(slog.LevelDebug, debugHandler)leveledHandler.RegisterHandler(slog.LevelInfo, infoHandler)leveledHandler.RegisterHandler(slog.LevelWarn, warnHandler)leveledHandler.RegisterHandler(slog.LevelError, errorHandler)slog.SetDefault(slog.New(leveledHandler))
}func main() {InitSlog()for i := 0; i < 1000; i++ {slog.Debug("Debug 日志", slog.String("test", "debug"))slog.Info("Info 日志", slog.String("test", "info"))slog.Warn("Warn 日志", slog.String("test", "warn"))slog.Error("Error 日志", slog.String("test", "error"), slog.Any("err", os.ErrNotExist))}ctx := context.WithValue(context.Background(), "trace_id", "123456")slog.InfoContext(ctx, "带上下文的 Info 日志")slog.Info("Info 日志", slog.String("trace_id", ctx.Value("trace_id").(string)))
}