fix: isolate malformed metadata source failures (#120)

Author: njzjz-bot

tests/test_source_error_isolation.py

@@ -0,0 +1,67 @@
+"""Tests for isolating expected metadata-source failures."""
+
+from __future__ import annotations
+
+import asyncio
+
+import pytest
+
+import wenxian.from_identifier as identifier_module
+from wenxian.reference import Reference
+
+
+def test_sync_doi_keeps_good_result_when_one_source_has_bad_payload(monkeypatch):
+    """Test one malformed source does not discard usable DOI metadata."""
+    monkeypatch.setattr(
+        identifier_module.Pubmed,
+        "from_doi",
+        lambda self, doi: Reference(title="Usable", journal="Journal"),
+    )
+    monkeypatch.setattr(
+        identifier_module.Crossref,
+        "from_doi",
+        lambda self, doi: (_ for _ in ()).throw(KeyError("message")),
+    )
+    monkeypatch.setattr(identifier_module.Arxiv, "from_doi", lambda self, doi: None)
+    monkeypatch.setattr(identifier_module.Chemrxiv, "from_doi", lambda self, doi: None)
+    monkeypatch.setattr(
+        identifier_module.Semanticscholar, "from_doi", lambda self, doi: None
+    )
+
+    assert identifier_module.from_doi("10.1234/example") == Reference(
+        title="Usable", journal="Journal"
+    )
+
+
+def test_async_doi_keeps_good_result_when_one_source_has_bad_payload(monkeypatch):
+    """Test async aggregation also isolates malformed source payloads."""
+
+    async def good(self, doi):
+        return Reference(title="Usable", journal="Journal")
+
+    async def bad(self, doi):
+        raise TypeError("malformed payload")
+
+    async def missing(self, doi):
+        return None
+
+    monkeypatch.setattr(identifier_module.Pubmed, "async_from_doi", good)
+    monkeypatch.setattr(identifier_module.Crossref, "async_from_doi", bad)
+    monkeypatch.setattr(identifier_module.Arxiv, "async_from_doi", missing)
+    monkeypatch.setattr(identifier_module.Chemrxiv, "async_from_doi", missing)
+    monkeypatch.setattr(identifier_module.Semanticscholar, "async_from_doi", missing)
+
+    assert asyncio.run(
+        identifier_module.async_from_doi("10.1234/example")
+    ) == Reference(title="Usable", journal="Journal")
+
+
+def test_native_programming_error_still_escapes(monkeypatch):
+    """Test unexpected programming errors are not swallowed on native Python."""
+    monkeypatch.setattr(identifier_module.sys, "platform", "linux")
+
+    def broken(identifier):
+        raise RuntimeError("bug")
+
+    with pytest.raises(RuntimeError, match="bug"):
+        identifier_module._fetch_safely("test", broken, "id")

wenxian/from_identifier.py

@@ -7,6 +7,7 @@
 from concurrent.futures import ThreadPoolExecutor
 from difflib import SequenceMatcher
 from typing import TYPE_CHECKING, TypeVar
+from xml.etree.ElementTree import ParseError
 
 from requests.exceptions import RequestException
 
@@ -25,6 +26,7 @@
     from collections.abc import Awaitable, Callable, Iterable
 
 T = TypeVar("T")
+_SOURCE_DATA_ERRORS = (KeyError, IndexError, TypeError, ValueError, ParseError)
 
 
 def _title_similarity(title1: str, title2: str) -> float:
@@ -40,7 +42,7 @@ def _fetch_safely(
     """Fetch from one source without aborting a fallback chain."""
     try:
         return fetcher(identifier)
-    except (OSError, RequestException) as exc:
+    except (OSError, RequestException, *_SOURCE_DATA_ERRORS) as exc:
         logger.warning("%s lookup failed for %s: %s", source, identifier, exc)
         return None
     except Exception as exc:
@@ -58,7 +60,7 @@ async def _async_fetch_safely(
     """Fetch from one source asynchronously without aborting other sources."""
     try:
         return await fetcher(identifier)
-    except (OSError, RequestException) as exc:
+    except (OSError, RequestException, *_SOURCE_DATA_ERRORS) as exc:
         logger.warning("%s lookup failed for %s: %s", source, identifier, exc)
         return None
     except Exception as exc: