Files
rag-ingestor/app/ingest/metadata.py

48 lines
1.3 KiB
Python

import re
from dataclasses import dataclass
from pathlib import PurePosixPath
SEMESTER_RE = re.compile(r"^\d+\.Semester$")
@dataclass(frozen=True)
class PathMetadata:
semester: str
fach: str
typ: str | None
def parse_path(file_path: str, ingest_root: str) -> PathMetadata | None:
"""Parse a Nextcloud file path into structured metadata.
Returns None when the path is outside the ingest root or does not match
the expected `<root>/<N>.Semester/<Fach>/[<typ>/...]/<file>` pattern.
Caller must pass a file path. Directory paths (with or without trailing
slash) produce undefined results — `PurePosixPath` strips trailing slashes,
so a directory ending in `/foo/` is indistinguishable from a file `/foo`.
"""
norm_path = file_path.lstrip("/")
norm_root = ingest_root.strip("/")
if not norm_path.startswith(norm_root + "/"):
return None
relative = norm_path[len(norm_root) + 1:]
parts = PurePosixPath(relative).parts
# Layout: [semester, fach, *inner, filename] — minimum 3 parts
if len(parts) < 3:
return None
semester, fach = parts[0], parts[1]
if not SEMESTER_RE.fullmatch(semester):
return None
inner = parts[2:-1] # everything between fach and filename
typ = inner[0] if inner else None
return PathMetadata(semester=semester, fach=fach, typ=typ)