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app/fritzbox.py

@@ -0,0 +1,33 @@
+import logging
+import time
+
+from fritzconnection import FritzConnection
+from fritzconnection.core.exceptions import FritzConnectionException
+
+log = logging.getLogger("fritzbox")
+
+
+class FritzBoxError(Exception):
+    pass
+
+
+def get_external_ip(host: str, port: int, user: str, password: str, retries: int = 3,
+                     backoff_seconds=(2, 5, 10)) -> str:
+    last_exc = None
+    for attempt in range(1, retries + 1):
+        try:
+            fc = FritzConnection(address=host, port=port, user=user, password=password)
+            result = fc.call_action("WANIPConn1", "GetExternalIPAddress")
+            ip = result.get("NewExternalIPAddress")
+            if not ip:
+                raise FritzBoxError("Leere Antwort von der FritzBox (kein NewExternalIPAddress)")
+            log.info("Externe IP von FritzBox erhalten: %s (Versuch %d/%d)", ip, attempt, retries)
+            return ip
+        except (FritzConnectionException, FritzBoxError, OSError) as exc:
+            last_exc = exc
+            log.warning("TR-064-Abfrage fehlgeschlagen (Versuch %d/%d): %s", attempt, retries, exc)
+            if attempt < retries:
+                sleep_time = backoff_seconds[min(attempt - 1, len(backoff_seconds) - 1)]
+                time.sleep(sleep_time)
+
+    raise FritzBoxError(f"Konnte externe IP nach {retries} Versuchen nicht ermitteln: {last_exc}")