refactor: refactoring of code

Add graceful shutdown server

internal/tls.go

@@ -0,0 +1,36 @@
+/*
+ * Copyright 2024 Jonas Kaninda
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+package pkg
+
+import (
+	"crypto/tls"
+	"fmt"
+)
+
+func (gatewayServer GatewayServer) initTLS() (*tls.Config, bool, error) {
+	cert, key := gatewayServer.gateway.SSLCertFile, gatewayServer.gateway.SSLKeyFile
+	if cert == "" || key == "" {
+		return nil, false, nil
+	}
+
+	tlsConfig, err := loadTLS(cert, key)
+	if err != nil {
+		return nil, false, fmt.Errorf("failed to load TLS config: %w", err)
+	}
+	return tlsConfig, true, nil
+}