Files
2026-08-26 14:13:11 +08:00

67 lines
2.3 KiB
Python

from __future__ import annotations
import hashlib
from pathlib import Path
IMAGE_SUFFIXES = {".png", ".jpg", ".jpeg", ".webp", ".svg"}
DOCUMENT_SUFFIXES = {".txt", ".md", ".csv", ".json", ".pdf", ".dxf", ".step", ".stp"}
MAX_IMAGE_BYTES = 10 * 1024 * 1024
MAX_DOCUMENT_BYTES = 2 * 1024 * 1024
MAX_EXTRACTED_CHARS = 30_000
def classify_upload(filename: str, mime: str, size: int) -> str:
suffix = Path(filename).suffix.lower()
if suffix in IMAGE_SUFFIXES or mime.startswith("image/"):
if size > MAX_IMAGE_BYTES:
raise ValueError("Image upload exceeds the 10 MB limit")
return "image"
if suffix in DOCUMENT_SUFFIXES:
if size > MAX_DOCUMENT_BYTES:
raise ValueError("Document upload exceeds the 2 MB limit")
return "document"
raise ValueError("Only PNG, JPG, WEBP, SVG, TXT, MD, CSV, JSON, PDF, DXF, and STEP/STP uploads are supported")
def extract_document_text(data: bytes) -> str:
# PDF extraction is optional so the API can still accept a reference when
# the local PDF dependency is unavailable; the binary remains available as
# the primary attachment artifact.
if data.startswith(b"%PDF"):
try:
from pypdf import PdfReader
import io
return "\n".join(page.extract_text() or "" for page in PdfReader(io.BytesIO(data)).pages)[:MAX_EXTRACTED_CHARS]
except Exception:
return "[PDF reference uploaded; text extraction unavailable]"
try:
text = data.decode("utf-8")
except UnicodeDecodeError as error:
return "[Binary CAD reference uploaded; structured geometry inspection is deferred to the CAD reference analyzer]"
return text[:MAX_EXTRACTED_CHARS]
def attachment_record(
conversation_id: str,
filename: str,
mime: str,
relative_path: str,
data: bytes,
kind: str,
extracted_path: str = "",
metadata: dict[str, object] | None = None,
) -> dict[str, object]:
return {
"id": Path(relative_path).stem,
"conversation_id": conversation_id,
"name": filename,
"kind": kind,
"path": relative_path,
"mime": mime or "application/octet-stream",
"size": len(data),
"sha256": hashlib.sha256(data).hexdigest(),
"extracted_path": extracted_path,
**(metadata or {}),
}