feat: introduce logger to config

main.go

@@ -2,6 +2,9 @@ package main
 
 import (
 	"fmt"
+	"log/slog"
+	"os"
+	"strings"
 
 	"realdnydns/pkg/config"
 	"realdnydns/pkg/dnsProvider"
@@ -15,12 +18,24 @@ import (
 )
 
 func main() {
+	logger := slog.New(slog.NewJSONHandler(os.Stdout, &slog.HandlerOptions{
+		Level: slog.LevelInfo,
+	}))
+
 	configClient := config.Config{}
 	err := configClient.Load("config.yaml")
 	if err != nil {
+		logger.Error("Failed to load config file",
+			slog.String("error", err.Error()))
 		panic(err)
 	}
 
+	if configClient.LogLevel != "" {
+		logger = slog.New(slog.NewJSONHandler(os.Stdout, &slog.HandlerOptions{
+			Level: slog.Level(config.LogLevelMap[strings.ToLower(configClient.LogLevel)]),
+		}))
+	}
+
 	var externalIpProvider externalIpProvider.ExternalIpProvider
 	switch configClient.ExternalIPProvider.Type {
 	case "plain":