res_levis_backend/internal/pkg/logger/logger.go

package logger

import (
	"io"
	"log"
	"log/slog"
	"os"
)

func CreateLogger(fname string) *slog.Logger {
	f, err := os.OpenFile(fname, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0666)
	if err != nil {
		log.Fatalf("Failed to open log file: %v\n", err)
	}
	// shell and log file multiwriter
	w := io.MultiWriter(os.Stderr, f)
	logger := slog.New(slog.NewJSONHandler(w, nil))
	return logger
}