From 93b20ba4dc14d2c6ab7a15b481125aafadb55bb5 Mon Sep 17 00:00:00 2001
From: Daniel Langbein <daniel@systemli.org>
Date: Wed, 28 Jun 2023 16:15:46 +0200
Subject: [PATCH] feat: argparse

---
 src/netcup_dns/main.py | 24 ++++++++++++++++--------
 1 file changed, 16 insertions(+), 8 deletions(-)

diff --git a/src/netcup_dns/main.py b/src/netcup_dns/main.py
index 75c39a7..a8b7d31 100644
--- a/src/netcup_dns/main.py
+++ b/src/netcup_dns/main.py
@@ -1,8 +1,8 @@
 #!/usr/bin/env python3
 # -*- coding: utf-8 -*-
+import argparse
 import ipaddress
 import json
-import sys
 from functools import lru_cache
 from pathlib import Path
 from typing import Type
@@ -17,13 +17,8 @@ def main():
     """
     The main effort is done by https://github.com/nbuchwitz/nc_dnsapi
     """
-    if len(sys.argv) > 1:
-        cfg_dir = Path(sys.argv[1])
-    else:
-        cfg_dir = Path('/etc/netcup-dns')
-
-    if not cfg_dir.exists():
-        raise Exception(f'The config directory is missing: {cfg_dir}')
+    args = parse_args()
+    cfg_dir: Path = args.cfg_dir
 
     cfg_files = [file for file in cfg_dir.iterdir() if file.name.endswith('.json') and file.is_file()]
     for cfg_file in cfg_files:
@@ -59,6 +54,19 @@ def main():
                     print(f'The {hostname}.{domain} {type_} record points already to {destination}')
 
 
+def parse_args():
+    parser = argparse.ArgumentParser(description='Update DNS A/AAAA records with your current external IP address'
+                                                 ' using the netcup DNS API.')
+    parser.add_argument('--config-directory',
+                        help='Path to directory where `.json` config files reside.',
+                        dest='cfg_dir',
+                        default=Path('/etc/netcup-dns'),
+                        type=Path)
+    args = parser.parse_args()
+
+    if not args.cfg_dir.exists():
+        raise Exception(f'The given config directory does not exist: {args.cfg_dir}')
+
 def update_record_destination(api: Client, domain: str, hostname: str, type_: str, destination: str) -> bool:
     """
     Updates the `destination` of the DNS record identified by `domain`, `hostname` and `type`.