add config ssl file check

pkg/config/config.go

@@ -76,5 +76,17 @@ func LoadConfig(p ...string) (err error) {
 		return err
 	}
 
+	if exists := utils.CheckExists(conf.Database.SSLCa, false); !exists {
+		return errors.New("ssl ca file not exists")
+	}
+
+	if exists := utils.CheckExists(conf.Database.SSLCrt, false); !exists {
+		return errors.New("ssl crt file not exists")
+	}
+
+	if exists := utils.CheckExists(conf.Database.SSLKey, false); !exists {
+		return errors.New("ssl key file not exists")
+	}
+
 	return
 }