Files
jobtrackingapp/tools/summarizer/parser_child.py
T

411 lines
17 KiB
Python

"""Resource-bounded CV document decoder invoked only as a child process."""
from __future__ import annotations
import argparse
import io
import json
import os
from pathlib import Path
import re
import sys
import zipfile
from pathlib import PurePosixPath
MAX_EXTRACT_CHARS = 200_000
MAX_PDF_PAGES = 40
MAX_DOCX_ENTRIES = 256
MAX_DOCX_UNCOMPRESSED_BYTES = 32 * 1024 * 1024
MAX_DOCX_ENTRY_BYTES = 8 * 1024 * 1024
MAX_DOCX_COMPRESSION_RATIO = 100
MAX_IMAGE_DIMENSION = 12_000
MAX_IMAGE_PIXELS = 40_000_000
MAX_PDF_PAGE_PIXELS = 12_000_000
MAX_PDF_OCR_PIXELS = 120_000_000
OCR_LANGUAGES = "eng"
IMAGE_EXTENSIONS = {".png", ".jpg", ".jpeg", ".webp"}
class ParserError(Exception):
def __init__(self, code: str):
super().__init__(code)
self.code = code
def _apply_resource_limits(cpu_seconds: int, memory_bytes: int) -> None:
if os.name != "posix":
return
import resource
resource.setrlimit(resource.RLIMIT_CPU, (cpu_seconds, cpu_seconds + 1))
resource.setrlimit(resource.RLIMIT_AS, (memory_bytes, memory_bytes))
resource.setrlimit(resource.RLIMIT_FSIZE, (1024 * 1024, 1024 * 1024))
resource.setrlimit(resource.RLIMIT_NOFILE, (64, 64))
resource.setrlimit(resource.RLIMIT_CORE, (0, 0))
def normalize_text(value: str) -> str:
value = value.replace("\x00", " ").replace("\r\n", "\n").replace("\r", "\n")
lines: list[str] = []
blank = False
for raw_line in value.split("\n"):
line = re.sub(r"[\t\f\v]+", " ", raw_line).strip()
if not line:
if lines and not blank:
lines.append("")
blank = True
continue
lines.append(line)
blank = False
return "\n".join(lines).strip()
def _check_extracted_size(text: str, limit: int = MAX_EXTRACT_CHARS) -> str:
if len(text) > limit:
raise ParserError("extracted_text_limit")
return text
def _check_image_size(image, *, pixel_limit: int = MAX_IMAGE_PIXELS) -> None:
width, height = image.size
if width <= 0 or height <= 0 or width > MAX_IMAGE_DIMENSION or height > MAX_IMAGE_DIMENSION:
raise ParserError("image_dimensions")
if width * height > pixel_limit:
raise ParserError("image_pixel_limit")
if getattr(image, "n_frames", 1) != 1:
raise ParserError("image_frames")
def validate_docx_container(
data: bytes,
*,
entry_limit: int = MAX_DOCX_ENTRIES,
total_limit: int = MAX_DOCX_UNCOMPRESSED_BYTES,
entry_size_limit: int = MAX_DOCX_ENTRY_BYTES,
ratio_limit: int = MAX_DOCX_COMPRESSION_RATIO,
) -> None:
try:
with zipfile.ZipFile(io.BytesIO(data)) as archive:
entries = archive.infolist()
names = {entry.filename for entry in entries}
if "[Content_Types].xml" not in names or "word/document.xml" not in names:
raise ParserError("docx_signature")
if len(entries) > entry_limit:
raise ParserError("docx_entry_limit")
total_size = 0
for entry in entries:
total_size += entry.file_size
if entry.file_size > entry_size_limit:
raise ParserError("docx_entry_size")
if entry.file_size > 0 and entry.compress_size == 0:
raise ParserError("docx_ratio")
if entry.compress_size > 0 and entry.file_size / entry.compress_size > ratio_limit:
raise ParserError("docx_ratio")
if total_size > total_limit:
raise ParserError("docx_expanded_size")
except ParserError:
raise
except (zipfile.BadZipFile, OSError) as exc:
raise ParserError("docx_signature") from exc
def extract_plain_text(data: bytes) -> str:
try:
decoded = data.decode("utf-8-sig")
except UnicodeDecodeError as exc:
raise ParserError("text_encoding") from exc
return _check_extracted_size(normalize_text(decoded))
def extract_docx_text(data: bytes) -> str:
validate_docx_container(data)
from docx import Document
document = Document(io.BytesIO(data))
parts: list[str] = []
blocks = document.iter_inner_content() if hasattr(document, "iter_inner_content") else document.paragraphs
for block in blocks:
if hasattr(block, "rows"):
for row in block.rows:
cells = [cell.text.strip() for cell in row.cells if cell.text and cell.text.strip()]
if cells:
parts.append(" | ".join(cells))
elif getattr(block, "text", "").strip():
text = block.text.strip()
style = (getattr(getattr(block, "style", None), "name", "") or "").lower()
if "role" in style and parts:
parts.append("")
parts.append(f"- {text}" if "bullet" in style else text)
return _check_extracted_size(normalize_text("\n".join(parts)))
def _ocr_image(image) -> str:
import pytesseract
if image.mode not in ("RGB", "L"):
image = image.convert("RGB")
return normalize_text(pytesseract.image_to_string(image, lang=OCR_LANGUAGES))
def extract_image_text(data: bytes, *, pixel_limit: int = MAX_IMAGE_PIXELS) -> str:
from PIL import Image
with Image.open(io.BytesIO(data)) as image:
_check_image_size(image, pixel_limit=pixel_limit)
return _check_extracted_size(_ocr_image(image))
def extract_pdf_text(data: bytes, *, page_limit: int = MAX_PDF_PAGES) -> tuple[str, bool, int]:
from pypdf import PdfReader
page_count = 0
extracted_pages: list[str] = []
try:
reader = PdfReader(io.BytesIO(data))
page_count = len(reader.pages)
if page_count > page_limit:
raise ParserError("pdf_page_limit")
for page in reader.pages:
try:
extracted_pages.append(page.extract_text(extraction_mode="layout") or "")
except TypeError:
extracted_pages.append(page.extract_text() or "")
except ParserError:
raise
except Exception:
extracted_pages = []
text = _check_extracted_size(normalize_text("\n".join(extracted_pages)))
if len(text) >= 80:
return text, False, page_count
import fitz
from PIL import Image
document = fitz.open(stream=data, filetype="pdf")
try:
page_count = document.page_count
if page_count > page_limit:
raise ParserError("pdf_page_limit")
ocr_pages: list[str] = []
total_pixels = 0
for page in document:
pixmap = page.get_pixmap(matrix=fitz.Matrix(2, 2), alpha=False)
page_pixels = pixmap.width * pixmap.height
total_pixels += page_pixels
if page_pixels > MAX_PDF_PAGE_PIXELS or total_pixels > MAX_PDF_OCR_PIXELS:
raise ParserError("pdf_ocr_limit")
with Image.open(io.BytesIO(pixmap.tobytes("png"))) as image:
_check_image_size(image, pixel_limit=MAX_PDF_PAGE_PIXELS)
ocr_pages.append(_ocr_image(image))
_check_extracted_size("\n".join(ocr_pages))
return _check_extracted_size(normalize_text("\n".join(ocr_pages))), True, page_count
finally:
document.close()
def extract(extension: str, data: bytes) -> dict[str, object]:
if extension in {".txt", ".md"}:
text = extract_plain_text(data)
return {"text": text, "ocr_used": False, "page_count": None}
if extension == ".docx":
text = extract_docx_text(data)
return {"text": text, "ocr_used": False, "page_count": None}
if extension == ".pdf":
text, ocr_used, page_count = extract_pdf_text(data)
return {"text": text, "ocr_used": ocr_used, "page_count": page_count}
if extension in IMAGE_EXTENSIONS:
text = extract_image_text(data)
return {"text": text, "ocr_used": True, "page_count": 1}
raise ParserError("unsupported_type")
def _validate_import_docx(data: bytes) -> None:
validate_docx_container(data)
from defusedxml import ElementTree
try:
with zipfile.ZipFile(io.BytesIO(data)) as archive:
names: set[str] = set()
for entry in archive.infolist():
name = entry.filename
path = PurePosixPath(name)
if name in names or path.is_absolute() or ".." in path.parts or "\\" in name or ":" in name or entry.flag_bits & 1:
raise ParserError("docx_unsafe_archive")
names.add(name)
if name.lower().endswith((".bin", ".emf", ".wmf")) or name.startswith("word/embeddings/"):
raise ParserError("external_content")
if name.endswith((".xml", ".rels")):
root = ElementTree.fromstring(archive.read(entry))
for node in root.iter():
if node.tag.rsplit("}", 1)[-1] in {"altChunk", "OLEObject", "object"}:
raise ParserError("external_content")
if node.attrib.get("TargetMode", "").lower() == "external":
# Hyperlinks are inert source data; converters cannot follow them in the sandbox.
from urllib.parse import urlsplit
if node.attrib.get("Type", "").endswith("/hyperlink") and urlsplit(node.attrib.get("Target", "")).scheme.lower() in {"http", "https", "mailto"}:
continue
raise ParserError("external_content")
target = node.attrib.get("Target", "")
if ":" in target or "\\" in target or target.startswith("/"):
raise ParserError("external_content")
except ParserError:
raise
except Exception as exc:
raise ParserError("docx_signature") from exc
def _validate_import_pdf(data: bytes) -> int:
if not data.startswith(b"%PDF-"):
raise ParserError("pdf_signature")
from pypdf import PdfReader
from pypdf.generic import ArrayObject, DictionaryObject, IndirectObject
try:
reader = PdfReader(io.BytesIO(data), strict=True)
if reader.is_encrypted:
raise ParserError("pdf_encrypted")
count = len(reader.pages)
if count > MAX_PDF_PAGES:
raise ParserError("pdf_page_limit")
forbidden = {"/OpenAction", "/AA", "/JS", "/JavaScript", "/Launch", "/GoToR", "/SubmitForm", "/ImportData", "/EmbeddedFiles", "/Filespec", "/RichMedia", "/XFA"}
pending = [(reader.trailer, 0)]
seen: set[int] = set()
while pending:
value, depth = pending.pop()
if isinstance(value, IndirectObject):
value = value.get_object()
if not isinstance(value, (DictionaryObject, ArrayObject)) or id(value) in seen:
continue
seen.add(id(value))
if depth > 40 or len(seen) > 10_000:
raise ParserError("pdf_object_limit")
if isinstance(value, DictionaryObject):
from urllib.parse import urlsplit
if "/URI" in value and urlsplit(str(value["/URI"])).scheme.lower() not in {"http", "https", "mailto"}:
raise ParserError("external_content")
if forbidden.intersection(value) or str(value.get("/S", "")) in forbidden or str(value.get("/Type", "")) in forbidden:
raise ParserError("external_content")
pending.extend((item, depth + 1) for item in value.values())
else:
pending.extend((item, depth + 1) for item in value)
return count
except ParserError:
raise
except Exception as exc:
raise ParserError("pdf_invalid") from exc
def extract_document(extension: str, data: bytes) -> dict[str, object]:
"""Model-free Docling conversion of validated bytes, never URLs or local paths."""
if not data or len(data) > 5 * 1024 * 1024:
raise ParserError("file_size_limit")
if extension == ".docx":
_validate_import_docx(data)
page_count = None
warnings = ["docx_page_numbers_unavailable", "ocr_disabled"]
elif extension == ".pdf":
page_count = _validate_import_pdf(data)
warnings = ["pdf_native_order_no_layout_or_tables", "ocr_disabled"]
else:
raise ParserError("unsupported_type")
from docling.datamodel.base_models import DocumentStream, InputFormat, ConversionStatus
from docling.datamodel.backend_options import MsWordBackendOptions, ThreadedDoclingParseBackendOptions
from docling.datamodel.pipeline_options import ConvertPipelineOptions, NativePdfPipelineOptions
from docling.document_converter import DocumentConverter, WordFormatOption, NativePdfFormatOption
from docling_core.types.doc import TextItem, TableItem
common = dict(enable_remote_services=False, allow_external_plugins=False, do_picture_classification=False, do_picture_description=False, document_timeout=20)
if extension == ".pdf":
source_format = InputFormat.PDF
option = NativePdfFormatOption(
pipeline_options=NativePdfPipelineOptions(**common, generate_page_images=False, generate_picture_images=False, parser_threads=1),
backend_options=ThreadedDoclingParseBackendOptions(parser_threads=1, max_concurrent_results=1, render_pages=False, include_bitmap_images=False),
)
else:
source_format = InputFormat.DOCX
option = WordFormatOption(
pipeline_options=ConvertPipelineOptions(**common),
backend_options=MsWordBackendOptions(render_chart_images=False, max_total_bytes=MAX_DOCX_UNCOMPRESSED_BYTES, max_file_bytes=MAX_DOCX_ENTRY_BYTES, max_member_count=MAX_DOCX_ENTRIES),
)
converter = DocumentConverter(allowed_formats=[source_format], format_options={source_format: option})
conversion = converter.convert(DocumentStream(name="document" + extension, stream=io.BytesIO(data)), max_num_pages=MAX_PDF_PAGES, max_file_size=5 * 1024 * 1024)
if conversion.status != ConversionStatus.SUCCESS:
raise ParserError("parser_failed")
blocks: list[dict[str, object]] = []
characters = 0
for item, _ in conversion.document.iterate_items():
if isinstance(item, TableItem):
text = normalize_text(item.export_to_markdown(doc=conversion.document))
kind = "table"
elif isinstance(item, TextItem):
text = normalize_text(item.text)
kind = {"section_header": "section_header", "title": "title", "list_item": "list_item"}.get(item.label.value, "paragraph")
else:
continue
if not text:
continue
characters += len(text) + (1 if blocks else 0)
if characters > MAX_EXTRACT_CHARS:
raise ParserError("extracted_text_limit")
if len(blocks) >= 5000:
raise ParserError("block_limit")
page = item.prov[0].page_no if extension == ".pdf" and item.prov else None
blocks.append({"id": f"b{len(blocks) + 1:04d}", "text": text, "kind": kind, "page": page})
if not blocks:
raise ParserError("no_text")
return {"text": "\n".join(block["text"] for block in blocks), "ocr_used": False, "page_count": page_count, "blocks": blocks, "warnings": warnings, "method": "docling-native-pdf-v1" if extension == ".pdf" else "docling-docx-v1"}
def _deny_import_side_effects(event: str, args: tuple) -> None:
# Model-free conversion has no reason to open a socket or invoke an external tool.
if event in {"socket.connect", "socket.connect_ex", "socket.getaddrinfo", "subprocess.Popen", "os.system"}:
raise ParserError("external_content")
def _write_result(path: Path, result: dict[str, object]) -> None:
path.write_text(json.dumps(result, ensure_ascii=False, separators=(",", ":")), encoding="utf-8")
def main() -> int:
parser = argparse.ArgumentParser(add_help=False)
parser.add_argument("--input", required=True)
parser.add_argument("--output", required=True)
parser.add_argument("--extension", required=True)
parser.add_argument("--cpu-seconds", type=int, default=20)
parser.add_argument("--memory-bytes", type=int, default=512 * 1024 * 1024)
parser.add_argument("--mode", choices=("legacy", "document"), default="legacy")
args = parser.parse_args()
output_path = Path(args.output)
try:
_apply_resource_limits(args.cpu_seconds, args.memory_bytes)
data = Path(args.input).read_bytes()
if args.mode == "document":
os.environ.update({"HF_HUB_OFFLINE": "1", "HF_HUB_DISABLE_TELEMETRY": "1", "TRANSFORMERS_OFFLINE": "1"})
# Cache trusted platform metadata before the document sandbox denies Linux uname.
import platform
platform.platform()
sys.addaudithook(_deny_import_side_effects)
result = extract_document(args.extension.lower(), data)
else:
result = extract(args.extension.lower(), data)
if not result.get("text"):
raise ParserError("no_text")
_write_result(output_path, {"ok": True, **result})
return 0
except ParserError as exc:
_write_result(output_path, {"ok": False, "code": exc.code})
return 2
except ImportError:
_write_result(output_path, {"ok": False, "code": "docling_unavailable" if args.mode == "document" else "parser_failed"})
return 3
except BaseException:
_write_result(output_path, {"ok": False, "code": "parser_failed"})
return 3
if __name__ == "__main__":
sys.exit(main())