Fix PermissionError when loading .netrc (#7237)

CHANGES/7237.bugfix

@@ -0,0 +1 @@
+Fixed ``PermissionError`` when .netrc is unreadable due to permissions.

CONTRIBUTORS.txt

@@ -163,6 +163,7 @@ Jake Davis
 Jakob Ackermann
 Jakub Wilk
 Jan Buchar
+Jan Gosmann
 Jarno Elonen
 Jashandeep Sohi
 Jean-Baptiste Estival

aiohttp/helpers.py

@@ -3,6 +3,7 @@
 import asyncio
 import base64
 import binascii
+import contextlib
 import dataclasses
 import datetime
 import enum
@@ -213,8 +214,11 @@
  except netrc.NetrcParseError as e:
  client_logger.warning("Could not parse .netrc file: %s", e)
  except OSError as e:
+ netrc_exists = False
+ with contextlib.suppress(OSError):
+ netrc_exists = netrc_path.is_file()
  # we couldn't read the file (doesn't exist, permissions, etc.)
- if netrc_env or netrc_path.is_file():
+ if netrc_env or netrc_exists:
  # only warn if the environment wanted us to load it,
  # or it appears like the default file does actually exist
  client_logger.warning("Could not read .netrc file: %s", e)

tests/test_helpers.py

@@ -6,6 +6,7 @@
 import platform
 import weakref
 from math import ceil, modf
+from pathlib import Path
 from unittest import mock
 from urllib.request import getproxies_environment
 
@@ -993,6 +994,26 @@ def test_netrc_from_env(expected_username: str):
  assert netrc_obj.authenticators("example.com")[0] == expected_username
 
 
+@pytest.fixture
+def protected_dir(tmp_path: Path):
+ protected_dir = tmp_path / "protected"
+ protected_dir.mkdir()
+ try:
+ protected_dir.chmod(0o600)
+ yield protected_dir
+ finally:
+ protected_dir.rmdir()
+
+
+def test_netrc_from_home_does_not_raise_if_access_denied(
+ protected_dir: Path, monkeypatch: pytest.MonkeyPatch
+):
+ monkeypatch.setattr(Path, "home", lambda: protected_dir)
+ monkeypatch.delenv("NETRC", raising=False)
+
+ helpers.netrc_from_env()
+
+
 @pytest.mark.parametrize(
  ["netrc_contents", "expected_auth"],
  [