WeKnora deployment source with the reviewed wiki identity, summary and recovery fixes

docreader/parser/xlsx_repair.py

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+"""Repair common XLSX packaging issues before openpyxl/pandas read."""
+
+from __future__ import annotations
+
+import io
+import re
+import zipfile
+from typing import Callable, Dict, Iterable, Set
+
+SST_PART = "xl/sharedStrings.xml"
+_SST_OVERRIDE_RE = re.compile(
+    r'<Override[^>]*PartName="[^"]*sharedStrings\.xml"[^>]*/>',
+    re.IGNORECASE,
+)
+_SST_REL_RE = re.compile(
+    r'<Relationship[^>]*Type="[^"]*sharedStrings"[^>]*/>',
+    re.IGNORECASE,
+)
+
+
+def repair_xlsx_bytes(content: bytes) -> bytes | None:
+    """Return repaired XLSX bytes, or None if no repair was applied.
+
+    Handles workbooks that reference ``xl/sharedStrings.xml`` in package
+    metadata but omit the part (common with some exporters). When worksheets
+    only use inline strings, manifest references are stripped so openpyxl can
+    read the file.
+    """
+    if not zipfile.is_zipfile(io.BytesIO(content)):
+        return None
+
+    with zipfile.ZipFile(io.BytesIO(content), "r") as zin:
+        names = _normalized_names(zin.namelist())
+        sst_path = _find_shared_strings_path(names)
+        if sst_path:
+            if sst_path == SST_PART:
+                return None
+            return _rewrite_zip(
+                zin, lambda files: _rename_shared_strings_part(files, sst_path)
+            )
+        if not _package_references_shared_strings(zin, names):
+            return None
+        if _worksheets_use_shared_string_cells(zin, names):
+            return None
+        return _rewrite_zip(zin, _strip_shared_strings_manifest)
+
+
+def _normalized_names(namelist: Iterable[str]) -> Set[str]:
+    return {name.replace("\\", "/") for name in namelist}
+
+
+def _find_shared_strings_path(names: Set[str]) -> str | None:
+    for name in names:
+        if name.lower().endswith("sharedstrings.xml"):
+            return name
+    return None
+
+
+def _package_references_shared_strings(
+    zin: zipfile.ZipFile, names: Set[str]
+) -> bool:
+    content_types = "[Content_Types].xml"
+    if content_types in names:
+        ct = zin.read(content_types).decode("utf-8", errors="replace")
+        if "sharedstrings.xml" in ct.lower():
+            return True
+
+    rels_path = "xl/_rels/workbook.xml.rels"
+    if rels_path in names:
+        rels = zin.read(rels_path).decode("utf-8", errors="replace")
+        if "sharedstrings" in rels.lower():
+            return True
+    return False
+
+
+def _worksheets_use_shared_string_cells(
+    zin: zipfile.ZipFile, names: Set[str]
+) -> bool:
+    for name in names:
+        if not name.startswith("xl/worksheets/") or not name.endswith(".xml"):
+            continue
+        sheet = zin.read(name).decode("utf-8", errors="replace")
+        if re.search(r'\bt="s"', sheet):
+            return True
+    return False
+
+
+def _rename_shared_strings_part(
+    files: Dict[str, bytes], source_path: str
+) -> Dict[str, bytes]:
+    updated = dict(files)
+    updated[SST_PART] = updated.pop(source_path)
+    return updated
+
+
+def _strip_shared_strings_manifest(files: Dict[str, bytes]) -> Dict[str, bytes]:
+    updated = dict(files)
+    ct_path = "[Content_Types].xml"
+    if ct_path in updated:
+        ct = updated[ct_path].decode("utf-8")
+        ct = _SST_OVERRIDE_RE.sub("", ct)
+        updated[ct_path] = ct.encode("utf-8")
+
+    rels_path = "xl/_rels/workbook.xml.rels"
+    if rels_path in updated:
+        rels = updated[rels_path].decode("utf-8")
+        rels = _SST_REL_RE.sub("", rels)
+        updated[rels_path] = rels.encode("utf-8")
+    return updated
+
+
+def _rewrite_zip(
+    zin: zipfile.ZipFile,
+    transform: Callable[[Dict[str, bytes]], Dict[str, bytes]],
+) -> bytes:
+    files: Dict[str, bytes] = {}
+    for info in zin.infolist():
+        name = info.filename.replace("\\", "/")
+        files[name] = zin.read(info.filename)
+    files = transform(files)
+
+    out = io.BytesIO()
+    with zipfile.ZipFile(out, "w", zipfile.ZIP_DEFLATED) as zout:
+        for name, data in files.items():
+            zout.writestr(name, data)
+    return out.getvalue()