log: allow setting log level dynamically

slogging/log.go

@@ -11,17 +11,30 @@ type Logger struct {
 	*slog.Logger
 }
 
+const (
+	LevelInfo int = iota
+	LevelDebug
+	LevelWarn
+	LevelError
+)
+
 var logger *Logger
 
+var opts slog.HandlerOptions
+
 func GetLogger() *Logger {
 	return logger
 }
 
 func Init(jsonHandler bool) *Logger {
+	opts = slog.HandlerOptions{
+		Level: slog.LevelInfo,
+	}
+
 	if jsonHandler {
-		logger = &Logger{slog.New(slog.NewJSONHandler(os.Stderr))}
+		logger = &Logger{slog.New(opts.NewJSONHandler(os.Stderr))}
 	} else {
-		logger = &Logger{slog.New(slog.NewTextHandler(os.Stderr))}
+		logger = &Logger{slog.New(opts.NewTextHandler(os.Stderr))}
 	}
 
 	logger.Info("slog logger initialised")
@@ -29,6 +42,32 @@ func Init(jsonHandler bool) *Logger {
 	return logger
 }
 
+// SetLevel allows setting log level and returns the pointer to the re-created
+// logger.
+func SetLevel(level int) *Logger {
+	switch level {
+	case LevelInfo:
+		opts.Level = slog.LevelInfo
+
+	case LevelDebug:
+		opts.Level = slog.LevelDebug
+
+	case LevelWarn:
+		opts.Level = slog.LevelWarn
+
+	case LevelError:
+		opts.Level = slog.LevelError
+	}
+
+	if _, ok := logger.Handler().(*slog.JSONHandler); ok {
+		logger = &Logger{slog.New(opts.NewJSONHandler(os.Stderr))}
+	} else {
+		logger = &Logger{slog.New(opts.NewTextHandler(os.Stderr))}
+	}
+
+	return logger
+}
+
 func (l *Logger) Debugf(msg string, args ...any) {
 	l.Debug(fmt.Sprintf(msg, args...))
 }