Fix infinite hang on schema refresh by adding timeout parameter (#2895)

Co-authored-by: Anders Forsman <anders.forsman@csc.fi>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

.github/workflows/tox.yml

@@ -69,7 +69,7 @@ jobs:
       WSLENV: FORCE_COLOR:PYTEST_REQPASS:TOXENV:GITHUB_STEP_SUMMARY
       # Number of expected test passes, safety measure for accidental skip of
       # tests. Update value if you add/remove tests.
-      PYTEST_REQPASS: 745
+      PYTEST_REQPASS: 747
 
     steps:
       - name: Activate WSL1

src/ansiblelint/schemas/main.py

@@ -104,7 +104,7 @@ def refresh_schemas(min_age_seconds: int = 3600 * 24) -> int:
         if etag:
             request.add_header("If-None-Match", f'"{data.get("etag")}"')
         try:
-            with urllib.request.urlopen(request) as response:
+            with urllib.request.urlopen(request, timeout=10) as response:
                 if response.status == 200:
                     content = response.read().decode("utf-8").rstrip()
                     etag = response.headers["etag"].strip('"')

test/test_schemas.py

@@ -1,5 +1,9 @@
 """Test schemas modules."""
+import logging
+import urllib
 from time import sleep
+from typing import Any
+from unittest.mock import DEFAULT, MagicMock, patch
 
 import pytest
 
@@ -42,3 +46,32 @@ def test_schema(
     assert len(matches) == len(expected_tags)
     for i, match in enumerate(matches):
         assert match.tag == expected_tags[i]
+
+
+def urlopen_side_effect(*_args: Any, **kwargs: Any) -> DEFAULT:
+    """Actual test that timeout parameter is defined."""
+    assert "timeout" in kwargs
+    assert kwargs["timeout"] > 0
+    return DEFAULT
+
+
+@patch("urllib.request")
+def test_requests_uses_timeout(mock_request: MagicMock) -> None:
+    """Test that schema refresh uses timeout."""
+    mock_request.urlopen.side_effect = urlopen_side_effect
+    refresh_schemas(min_age_seconds=0)
+    mock_request.urlopen.assert_called()
+
+
+@patch("urllib.request")
+def test_request_timeouterror_handling(
+    mock_request: MagicMock, caplog: pytest.LogCaptureFixture
+) -> None:
+    """Test that schema refresh can handle time out errors."""
+    error_msg = "Simulating handshake operation time out."
+    mock_request.urlopen.side_effect = urllib.error.URLError(TimeoutError(error_msg))
+    with caplog.at_level(logging.DEBUG):
+        assert refresh_schemas(min_age_seconds=0) == 1
+    mock_request.urlopen.assert_called()
+    assert "Skipped schema refresh due to unexpected exception: " in caplog.text
+    assert error_msg in caplog.text