fix(resm): reject unsafe PDF title candidates

CLAUDE.md

@@ -181,7 +181,10 @@ Title quality is tracked on `Paper` with the original value retained only when a
 is applied. `python manage.py audit_paper_titles` performs a dry-run audit by default;
 `--apply` writes only high-confidence XML corrections unless `--allow-medium` is explicitly
 provided for reviewed PDF candidates. The audit checks physical XML/PDF files even when
-legacy `has_fulltext_*` flags are stale.
+legacy `has_fulltext_*` flags are stale. PDF first-page layout guesses always remain low
+confidence and are never bulk-applied; PDF metadata also rejects filenames and generic titles.
+`rollback_pdf_title_corrections` restores PDF-derived corrections from `title_raw` and is a
+dry-run unless `--apply` is passed.
 
 Download behavior is stateful:
 

apps/resm/management/commands/rollback_pdf_title_corrections.py

@@ -0,0 +1,54 @@
+"""回滚误用 PDF 候选矫正的标题。"""
+from django.core.management.base import BaseCommand
+from django.utils import timezone
+
+from apps.resm.models import Paper
+from apps.resm.title_utils import assess_title
+
+
+class Command(BaseCommand):
+    help = "将 PDF 自动矫正标题恢复为 title_raw；默认 dry-run"
+
+    def add_arguments(self, parser):
+        parser.add_argument("--doi", action="append", default=[], help="只回滚指定 DOI，可重复")
+        parser.add_argument("--keep-doi", action="append", default=[], help="保留的 DOI，可重复")
+        parser.add_argument("--apply", action="store_true", help="实际回滚；默认只预览")
+
+    def handle(self, *args, **opts):
+        keep = [doi.strip().lower() for doi in opts["keep_doi"] if doi.strip()]
+        selected = [doi.strip().lower() for doi in opts["doi"] if doi.strip()]
+        qs = Paper.objects.filter(
+            title_quality_status=Paper.TITLE_CORRECTED,
+            title_source__in=("pdf_metadata", "pdf_first_page"),
+            title_raw__isnull=False,
+        ).exclude(title_raw="").order_by("id")
+        if selected:
+            qs = qs.filter(doi__in=selected)
+        if keep:
+            qs = qs.exclude(doi__in=keep)
+
+        count = 0
+        for paper in qs.iterator(chunk_size=500):
+            count += 1
+            self.stdout.write(
+                f"[rollback] {paper.doi} {paper.title!r} -> {paper.title_raw!r}"
+            )
+            if not opts["apply"]:
+                continue
+            restored = paper.title_raw
+            paper.title = restored
+            paper.title_raw = None
+            paper.title_source = None
+            paper.title_quality_status = (
+                Paper.TITLE_SUSPECT if assess_title(restored).suspect
+                else Paper.TITLE_UNCHECKED
+            )
+            paper.title_verified_at = None
+            paper.update_time = timezone.now()
+            paper.save(update_fields=[
+                "title", "title_raw", "title_source", "title_quality_status",
+                "title_verified_at", "update_time",
+            ])
+
+        mode = "apply" if opts["apply"] else "dry-run"
+        self.stdout.write(self.style.SUCCESS(f"完成({mode}) rollback={count}"))

apps/resm/test_title_utils.py

@@ -97,6 +97,30 @@ class PdfTitleExtractionTests(unittest.TestCase):
         self.assertEqual(candidate.confidence, "medium")
         self.assertEqual(candidate.evidence, "pdf_metadata+doi")
 
+    def test_rejects_layout_filename_and_keeps_first_page_low_confidence(self):
+        handle = tempfile.NamedTemporaryFile("wb", suffix=".pdf", delete=False)
+        self.addCleanup(lambda: os.path.exists(handle.name) and os.unlink(handle.name))
+        handle.write(b"%PDF-placeholder")
+        handle.close()
+
+        page = types.SimpleNamespace(
+            extract_text=lambda: (
+                "Correct Article Title\nMohamed Shamseldin\n"
+                "https://doi.org/10.1234/example.1\nAbstract"
+            )
+        )
+        reader = types.SimpleNamespace(
+            pages=[page], metadata=types.SimpleNamespace(title="article-layout.indd")
+        )
+        module = types.SimpleNamespace(PdfReader=lambda *args, **kwargs: reader)
+        with patch.dict("sys.modules", {"pypdf": module}):
+            candidate = extract_title_from_pdf(
+                handle.name, "10.1234/example.1", "Mohamed Shamseldin"
+            )
+        self.assertIsNotNone(candidate)
+        self.assertEqual(candidate.source, "pdf_first_page")
+        self.assertEqual(candidate.confidence, "low")
+
 
 if __name__ == "__main__":
     unittest.main()

apps/resm/title_utils.py

@@ -25,7 +25,9 @@ _WEB_MARKERS = (
 _DOCUMENT_MARKERS = ("author:", "authors:", "abstract:", "document type:")
 _GENERIC_PDF_TITLES = {
     "untitled", "microsoft word", "document", "article", "full text", "pdf",
+    "no job name",
 }
+_FILE_TITLE_RE = re.compile(r"(?:\.eps|\.indd|\.docx?|\.pdf|\.tex)$", re.I)
 
 
 @dataclass(frozen=True)
@@ -106,6 +108,21 @@ def is_usable_title(value: Optional[str]) -> bool:
     return True
 
 
+def _is_usable_pdf_metadata_title(value: Optional[str]) -> bool:
+    """PDF Title 属性经常是排版文件名，使用比普通标题更严格的门槛。"""
+    title = clean_title(value)
+    assessment = assess_title(title)
+    if not is_usable_title(title):
+        return False
+    if assessment.plain_length < 15 or assessment.word_count < 3:
+        return False
+    if title.casefold() in _GENERIC_PDF_TITLES or _FILE_TITLE_RE.search(title):
+        return False
+    if re.fullmatch(r"(?:issn\s*)?[\dXx-]{7,}", title):
+        return False
+    return True
+
+
 def is_better_title(current: Optional[str], candidate: Optional[str]) -> bool:
     old = assess_title(current)
     new = assess_title(candidate)
@@ -237,7 +254,7 @@ def extract_title_from_pdf(
 
     identity = _identity_evidence(page_text, expected_doi or "", first_author or "")
     meta_title = clean_title(getattr(metadata, "title", "") if metadata else "")
-    if meta_title and meta_title.casefold() not in _GENERIC_PDF_TITLES and is_usable_title(meta_title):
+    if _is_usable_pdf_metadata_title(meta_title):
         return FulltextTitleCandidate(
             title=meta_title,
             source="pdf_metadata",
@@ -250,7 +267,8 @@ def extract_title_from_pdf(
         return FulltextTitleCandidate(
             title=page_title,
             source="pdf_first_page",
-            confidence="medium" if identity else "low",
+            # 首页文本顺序受版式影响很大，只输出人工复核候选，绝不批量自动采用。
+            confidence="low",
             evidence=f"pdf_first_page+{identity}" if identity else "pdf_first_page_only",
         )
     return None