Files
nextcloud-mcp-server/nextcloud_mcp_server/document_processors/pymupdf.py
T
Chris Coutinho 31fade9730 perf: Optimize PDF processing with parallel extraction and single-render highlights
Phase 1 - PDF Highlighting Optimization:
- Render each page ONCE instead of once per chunk (N chunks = 1 render, not N)
- Use PIL to draw bounding boxes on copied base images (fast) instead of
  re-rendering page via pymupdf (slow)
- Add _find_chunk_bbox() to extract bbox without modifying page

Phase 2 - Parallel Page Extraction:
- Use anyio task group with run_sync() for parallel page extraction
- Each page extracted in separate thread via anyio.to_thread.run_sync()
- Event loop stays responsive during extraction
- Remove obsolete _process_sync() method

Expected improvement: 30-50% reduction in total PDF processing time.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>
2025-11-22 03:11:56 +01:00

289 lines
9.6 KiB
Python

"""Document processor using PyMuPDF (fitz) library."""
import logging
import pathlib
import tempfile
from collections.abc import Awaitable, Callable
from typing import Any, Optional
import pymupdf
import pymupdf.layout
from .base import DocumentProcessor, ProcessingResult, ProcessorError
# Activate layout analysis for better text extraction
pymupdf.layout.activate()
import pymupdf4llm # noqa
logger = logging.getLogger(__name__)
class PyMuPDFProcessor(DocumentProcessor):
"""Document processor using PyMuPDF library for PDF processing.
PyMuPDF (fitz) is a fast, local PDF processing library that extracts text,
metadata, and images without requiring external API calls.
Features:
- Fast text extraction with layout preservation
- PDF metadata extraction (title, author, creation date, page count)
- Image extraction for future multimodal support
- Page number tracking for precise citations
"""
SUPPORTED_TYPES = {
"application/pdf",
}
def __init__(
self,
extract_images: bool = True,
image_dir: Optional[str | pathlib.Path] = None,
):
"""Initialize PyMuPDF processor.
Args:
extract_images: Whether to extract embedded images from PDFs
image_dir: Directory to store extracted images (defaults to temp directory)
"""
self.extract_images = extract_images
if image_dir is None:
self.image_dir = pathlib.Path(tempfile.gettempdir()) / "pdf-images"
else:
self.image_dir = pathlib.Path(image_dir)
# Create image directory if it doesn't exist
if self.extract_images:
self.image_dir.mkdir(exist_ok=True, parents=True)
logger.info(
f"Initialized PyMuPDFProcessor with image extraction to {self.image_dir}"
)
else:
logger.info("Initialized PyMuPDFProcessor without image extraction")
@property
def name(self) -> str:
return "pymupdf"
@property
def supported_mime_types(self) -> set[str]:
return self.SUPPORTED_TYPES
async def process(
self,
content: bytes,
content_type: str,
filename: Optional[str] = None,
options: Optional[dict[str, Any]] = None,
progress_callback: Optional[
Callable[[float, Optional[float], Optional[str]], Awaitable[None]]
] = None,
) -> ProcessingResult:
"""Process a PDF document and extract text, metadata, and images.
Args:
content: PDF document bytes
content_type: MIME type (should be application/pdf)
filename: Optional filename for better error messages
options: Processing options (currently unused)
progress_callback: Optional callback for progress updates
Returns:
ProcessingResult with extracted text and metadata
Raises:
ProcessorError: If PDF processing fails
"""
import anyio
try:
if progress_callback:
await progress_callback(0, 100, "Opening PDF document")
# Open document and extract metadata in thread
doc = await anyio.to_thread.run_sync( # type: ignore[attr-defined]
lambda: pymupdf.open("pdf", content)
)
metadata = self._extract_metadata(doc, filename)
metadata["file_size"] = len(content)
page_count = doc.page_count
if progress_callback:
await progress_callback(10, 100, f"Extracting {page_count} pages")
# Prepare image directory if needed
pdf_image_dir = None
if self.extract_images:
pdf_id = filename.replace("/", "_") if filename else "unknown"
pdf_image_dir = self.image_dir / pdf_id
pdf_image_dir.mkdir(exist_ok=True, parents=True)
# OPTIMIZATION: Extract pages in parallel using anyio task group
page_texts = await self._extract_pages_parallel(
doc, page_count, pdf_image_dir
)
if progress_callback:
await progress_callback(90, 100, "Building result")
# Calculate page boundaries (sequential, fast)
page_boundaries = []
current_offset = 0
for page_num, page_md in enumerate(page_texts):
page_boundaries.append(
{
"page": page_num + 1,
"start_offset": current_offset,
"end_offset": current_offset + len(page_md),
}
)
current_offset += len(page_md)
# Collect image paths
image_paths = []
if pdf_image_dir and pdf_image_dir.exists():
image_paths = [str(p) for p in pdf_image_dir.glob("*")]
# Build final text and metadata
md_text = "".join(page_texts)
metadata["has_images"] = len(image_paths) > 0
if image_paths:
metadata["image_count"] = len(image_paths)
metadata["image_paths"] = image_paths
metadata["page_boundaries"] = page_boundaries
# Close document
doc.close()
if progress_callback:
await progress_callback(100, 100, "Processing complete")
logger.info(
f"Successfully processed PDF {filename or '<bytes>'}: "
f"{metadata['page_count']} pages, {len(md_text)} chars, "
f"{metadata.get('image_count', 0)} images"
)
return ProcessingResult(
text=md_text,
metadata=metadata,
processor=self.name,
success=True,
)
except Exception as e:
error_msg = f"Failed to process PDF {filename or '<bytes>'}: {e}"
logger.error(error_msg, exc_info=True)
raise ProcessorError(error_msg) from e
async def _extract_pages_parallel(
self,
doc: pymupdf.Document,
page_count: int,
pdf_image_dir: pathlib.Path | None,
) -> list[str]:
"""Extract text from all pages in parallel using anyio.
Args:
doc: Opened PyMuPDF document
page_count: Number of pages to extract
pdf_image_dir: Directory for extracted images (or None)
Returns:
List of page texts in order
"""
import anyio
results: list[str | None] = [None] * page_count
async def extract_one(page_num: int) -> None:
"""Extract single page in thread pool."""
def do_extract() -> str:
return pymupdf4llm.to_markdown(
doc,
pages=[page_num],
write_images=self.extract_images,
image_path=pdf_image_dir if self.extract_images else None,
page_chunks=False,
)
results[page_num] = await anyio.to_thread.run_sync(do_extract) # type: ignore[attr-defined]
# Run all page extractions in parallel
async with anyio.create_task_group() as tg:
for page_num in range(page_count):
tg.start_soon(extract_one, page_num)
# Verify all pages extracted
final_results: list[str] = []
for i, text in enumerate(results):
if text is None:
raise ProcessorError(f"Page {i} extraction failed")
final_results.append(text)
return final_results
def _extract_metadata(
self, doc: pymupdf.Document, filename: Optional[str]
) -> dict[str, Any]:
"""Extract metadata from PDF document.
Args:
doc: Opened PyMuPDF document
filename: Optional filename
Returns:
Dictionary with PDF metadata
"""
metadata: dict[str, Any] = {}
# Basic document info
metadata["page_count"] = doc.page_count
metadata["format"] = "PDF 1." + str(
doc.pdf_version() if hasattr(doc, "pdf_version") else "?" # type: ignore[call-non-callable]
)
if filename:
metadata["filename"] = filename
# Extract PDF metadata dictionary
pdf_metadata = doc.metadata
if pdf_metadata:
# Standard PDF metadata fields
if pdf_metadata.get("title"):
metadata["title"] = pdf_metadata["title"]
if pdf_metadata.get("author"):
metadata["author"] = pdf_metadata["author"]
if pdf_metadata.get("subject"):
metadata["subject"] = pdf_metadata["subject"]
if pdf_metadata.get("keywords"):
metadata["keywords"] = pdf_metadata["keywords"]
if pdf_metadata.get("creator"):
metadata["creator"] = pdf_metadata["creator"]
if pdf_metadata.get("producer"):
metadata["producer"] = pdf_metadata["producer"]
if pdf_metadata.get("creationDate"):
metadata["creation_date"] = pdf_metadata["creationDate"]
if pdf_metadata.get("modDate"):
metadata["modification_date"] = pdf_metadata["modDate"]
return metadata
async def health_check(self) -> bool:
"""Check if PyMuPDF is available and working.
Returns:
True if processor is ready to use
"""
try:
# Try to create a simple PDF in memory
test_doc = pymupdf.open()
test_doc.close()
return True
except Exception as e:
logger.error(f"PyMuPDF health check failed: {e}")
return False