apply request timeout also while waiting for a connection from pool

src/nominatim_api/timeout.py

@@ -0,0 +1,24 @@
+# SPDX-License-Identifier: GPL-3.0-or-later
+#
+# This file is part of Nominatim. (https://nominatim.org)
+#
+# Copyright (C) 2025 by the Nominatim developer community.
+# For a full list of authors see the git log.
+"""
+Helpers for handling of timeouts for request.
+"""
+from typing import Union, Optional
+import asyncio
+
+
+class Timeout:
+    """ A class that provides helper functions to ensure a given timeout
+        is respected. Can only be used from coroutines.
+    """
+    def __init__(self, timeout: Optional[Union[int, float]]) -> None:
+        self.abs = None if timeout is None else asyncio.get_running_loop().time() + timeout
+
+    def is_elapsed(self) -> bool:
+        """ Check if the timeout has already passed.
+        """
+        return (self.abs is not None) and (asyncio.get_running_loop().time() >= self.abs)