slog example

slogexmaple.go

func logRun() {
	//ctx := context.Background()
	replace := func(groups []string, a slog.Attr) slog.Attr {
		switch {
		case a.Key == slog.MessageKey:
			return slog.Attr{Key: "message", Value: a.Value}
		case a.Key == slog.LevelKey:
			if l := a.Value.Any().(slog.Level); l == slog.LevelWarn {
				return slog.String("severity", "WARNING")
			}
			return slog.Attr{Key: "severity", Value: a.Value}
		}
		return a
	}
	logger := slog.New(slog.NewJSONHandler(os.Stdout, &slog.HandlerOptions{ReplaceAttr: replace}))
	logger2 := logger.With("foo", 1)
	logger.Info("w", slog.Group("request", "method", "GET", slog.Int("status", 200)))
	logger2.Info("w2")
	logger.Warn("w", slog.Group("request", "method", "GET", slog.Group("res", slog.Int("status", 200))))
	logger.Info("w3")
}