pdf2markdown / app.py
broadfield-dev's picture
Update app.py
8323e8f verified
import os
import io
import re # Still needed for some image filename manipulation if any, but not for text formatting
import logging
import subprocess
from datetime import datetime
import urllib.parse
import tempfile
import json # For streaming JSON messages
import time # For gevent.sleep
from flask import Flask, request, render_template, Response, stream_with_context
from werkzeug.utils import secure_filename
# Ensure gevent is imported and monkey patched if needed for other libraries
# from gevent import monkey
# monkey.patch_all() # Apply this early if you suspect issues with other libs
import requests # For requests.exceptions.HTTPError
from requests.exceptions import HTTPError as RequestsHTTPError # Specific import for clarity
# pdfplumber is no longer needed
import pdf2image
from pdf2image import convert_from_path, convert_from_bytes
# from pdf2image.exceptions import ... # If you need to catch specific pdf2image errors
import pytesseract
from PIL import Image
from huggingface_hub import HfApi, create_repo
# --- Flask App Initialization ---
app = Flask(__name__)
app.config['UPLOAD_FOLDER'] = tempfile.gettempdir()
app.config['MAX_CONTENT_LENGTH'] = 50 * 1024 * 1024 # 50 MB limit for uploads, adjust as needed
# --- Logging Configuration ---
logging.basicConfig(level=logging.INFO, format="%(asctime)s - %(levelname)s - %(message)s")
logger = logging.getLogger(__name__)
# --- Hugging Face Configuration ---
HF_TOKEN = os.getenv("HF_TOKEN")
HF_DATASET_REPO_NAME = os.getenv("HF_DATASET_REPO_NAME", "pdf-images-extracted")
hf_api = HfApi()
# --- Helper to yield messages for streaming ---
def yield_message(type, data):
"""Helper to format messages as JSON strings for streaming."""
return json.dumps({"type": type, **data}) + "\n"
# --- PDF Processing Helper Functions (Adapted for Streaming) ---
def check_poppler():
try:
result = subprocess.run(["pdftoppm", "-v"], capture_output=True, text=True, check=False)
version_info_log = result.stderr.strip() if result.stderr else result.stdout.strip()
if version_info_log:
logger.info(f"Poppler version check: {version_info_log.splitlines()[0] if version_info_log else 'No version output'}")
else:
logger.info("Poppler 'pdftoppm -v' ran. Assuming Poppler is present.")
return True
except FileNotFoundError:
logger.error("Poppler (pdftoppm command) not found. Ensure poppler-utils is installed and in PATH.")
return False
except Exception as e:
logger.error(f"An unexpected error occurred during Poppler check: {str(e)}")
return False
def ensure_hf_dataset():
if not HF_TOKEN:
msg = "HF_TOKEN is not set. Cannot ensure Hugging Face dataset. Image uploads will fail."
logger.warning(msg)
return "Error: " + msg
try:
repo_id_obj = create_repo(repo_id=HF_DATASET_REPO_NAME, token=HF_TOKEN, repo_type="dataset", exist_ok=True)
logger.info(f"Dataset repo ensured: {repo_id_obj.repo_id}")
return repo_id_obj.repo_id
except RequestsHTTPError as e:
if e.response is not None and e.response.status_code == 409:
logger.info(f"Dataset repo '{HF_DATASET_REPO_NAME}' already exists (HTTP 409).")
try:
user_info = hf_api.whoami(token=HF_TOKEN)
namespace = user_info.get('name') if user_info else None
if namespace:
return f"{namespace}/{HF_DATASET_REPO_NAME}"
else:
logger.warning(f"Could not determine namespace for existing repo '{HF_DATASET_REPO_NAME}'. Using generic ID.")
return HF_DATASET_REPO_NAME
except Exception as whoami_e:
logger.error(f"Could not determine namespace for existing repo via whoami due to: {whoami_e}. Using generic ID.")
return HF_DATASET_REPO_NAME
else:
status_code = e.response.status_code if e.response is not None else "Unknown"
logger.error(f"Hugging Face dataset HTTP error (Status: {status_code}): {str(e)}")
return f"Error: Failed to access or create dataset '{HF_DATASET_REPO_NAME}' due to HTTP error: {str(e)}"
except Exception as e:
logger.error(f"Hugging Face dataset general error: {str(e)}", exc_info=True)
return f"Error: Failed to access or create dataset '{HF_DATASET_REPO_NAME}': {str(e)}"
def upload_image_to_hf_stream(image_pil, filename_base, page_num_for_log=""):
repo_id_or_error = ensure_hf_dataset()
if isinstance(repo_id_or_error, str) and repo_id_or_error.startswith("Error"):
return repo_id_or_error
repo_id = repo_id_or_error
temp_image_path = None
try:
timestamp = datetime.now().strftime("%Y%m%d_%H%M%S_%f")
repo_filename = f"images/{filename_base}_{page_num_for_log}_{timestamp}.png"
os.makedirs(app.config['UPLOAD_FOLDER'], exist_ok=True)
with tempfile.NamedTemporaryFile(delete=False, suffix=".png", dir=app.config['UPLOAD_FOLDER']) as tmp_file:
temp_image_path = tmp_file.name
image_pil.save(temp_image_path, format="PNG")
logger.info(f"Attempting to upload {temp_image_path} to {repo_id}/{repo_filename}")
file_url = hf_api.upload_file(
path_or_fileobj=temp_image_path, path_in_repo=repo_filename,
repo_id=repo_id, repo_type="dataset", token=HF_TOKEN
)
logger.info(f"Successfully uploaded image: {file_url}")
return file_url
except Exception as e:
logger.error(f"Image upload error for {filename_base}{page_num_for_log}: {str(e)}", exc_info=True)
return f"Error uploading image {filename_base}{page_num_for_log}: {str(e)}"
finally:
if temp_image_path and os.path.exists(temp_image_path):
try: os.remove(temp_image_path)
except OSError as ose: logger.error(f"Error removing temp image file {temp_image_path}: {ose}")
# format_page_text_to_markdown_chunk function is removed as it's no longer used.
# --- Main PDF Processing Logic (Generator Function for Streaming) ---
def generate_pdf_conversion_stream(pdf_input_source_path_or_url):
try:
yield yield_message("markdown_replace", {"content": "# Extracted Images and OCR Text\n\n"})
time.sleep(0.01)
actual_pdf_input_for_images = None
is_input_bytes = False
source_is_url = isinstance(pdf_input_source_path_or_url, str) and \
pdf_input_source_path_or_url.startswith(('http://', 'https://'))
if source_is_url:
yield yield_message("status", {"message": f"Downloading PDF from URL..."})
time.sleep(0.01)
try:
response = requests.get(pdf_input_source_path_or_url, stream=False, timeout=60)
response.raise_for_status()
actual_pdf_input_for_images = response.content
is_input_bytes = True
yield yield_message("status", {"message": f"PDF downloaded from URL ({len(actual_pdf_input_for_images)/1024:.2f} KB)."})
time.sleep(0.01)
except RequestsHTTPError as e:
logger.error(f"URL fetch HTTP error: {str(e)} (Status: {e.response.status_code if e.response else 'N/A'})", exc_info=True)
yield yield_message("error", {"message": f"Error fetching PDF from URL (HTTP {e.response.status_code if e.response else 'N/A'}): {e.response.reason if e.response else str(e)}"})
return
except requests.RequestException as e:
logger.error(f"URL fetch network error: {str(e)}", exc_info=True)
yield yield_message("error", {"message": f"Network error fetching PDF from URL: {str(e)}"})
return
else:
actual_pdf_input_for_images = pdf_input_source_path_or_url
is_input_bytes = False
yield yield_message("status", {"message": f"Processing local PDF file..."})
time.sleep(0.01)
# ----- Direct Text Extraction (using pdfplumber) is REMOVED -----
# ----- Image Extraction and OCR -----
if not check_poppler():
yield yield_message("error", {"message": "Poppler (for image extraction) not found or not working."})
else:
yield yield_message("status", {"message": "Starting image extraction and OCR..."})
# The "## Extracted Images" title is now more specific
yield yield_message("markdown_chunk", {"content": "## Extracted Images & OCR Text from PDF Pages\n\n"})
if not HF_TOKEN:
yield yield_message("markdown_chunk", {"content": "**Note:** `HF_TOKEN` not set. Images will be described but not uploaded.\n\n"})
time.sleep(0.01)
extracted_pil_images_overall_count = 0
try:
if actual_pdf_input_for_images:
try: # Batched conversion attempt
pdf_info = None
if is_input_bytes:
pdf_info = pdf2image.pdfinfo_from_bytes(actual_pdf_input_for_images, userpw=None, poppler_path=None)
else:
pdf_info = pdf2image.pdfinfo_from_path(actual_pdf_input_for_images, userpw=None, poppler_path=None)
num_image_pages = pdf_info.get("Pages", 0)
yield yield_message("status", {"message": f"PDF has {num_image_pages} page(s) for image conversion and OCR."})
batch_size = 1
for page_idx_start in range(1, num_image_pages + 1, batch_size):
page_idx_end = min(page_idx_start + batch_size - 1, num_image_pages)
yield yield_message("status", {"message": f"Converting PDF page(s) {page_idx_start}-{page_idx_end} to image(s)..."})
time.sleep(0.01)
page_images_pil = []
if is_input_bytes:
page_images_pil = convert_from_bytes(actual_pdf_input_for_images, dpi=150, first_page=page_idx_start, last_page=page_idx_end)
else:
page_images_pil = convert_from_path(actual_pdf_input_for_images, dpi=150, first_page=page_idx_start, last_page=page_idx_end)
for img_idx_in_batch, img_pil in enumerate(page_images_pil):
extracted_pil_images_overall_count += 1
current_pdf_page_num = page_idx_start + img_idx_in_batch
page_num_for_log = f"pdfpage_{current_pdf_page_num}"
yield yield_message("status", {"message": f"Processing image {extracted_pil_images_overall_count} (from PDF page {current_pdf_page_num}) (OCR & Upload)..."})
time.sleep(0.01)
ocr_text = ""
try:
ocr_text = pytesseract.image_to_string(img_pil).strip()
if ocr_text: yield yield_message("status", {"message": f" OCR successful for image {extracted_pil_images_overall_count}."})
else: yield yield_message("status", {"message": f" OCR complete for image {extracted_pil_images_overall_count} (no text found)."})
except Exception as ocr_e:
logger.error(f"OCR error for image {extracted_pil_images_overall_count}: {str(ocr_e)}")
ocr_text = f"OCR failed: {str(ocr_e)}"
image_md_chunk = f"### Image from PDF Page {current_pdf_page_num}\n"
if HF_TOKEN:
image_url_or_error = upload_image_to_hf_stream(img_pil, "pdf_page_image", page_num_for_log)
if isinstance(image_url_or_error, str) and not image_url_or_error.startswith("Error"):
image_md_chunk += f"![Image from PDF Page {current_pdf_page_num}]({image_url_or_error})\n"
yield yield_message("status", {"message": f" Image {extracted_pil_images_overall_count} uploaded."})
else:
image_md_chunk += f"**Image {extracted_pil_images_overall_count} (Upload Error):** {str(image_url_or_error)}\n\n"
yield yield_message("error", {"message": f"Failed to upload image {extracted_pil_images_overall_count}: {str(image_url_or_error)}"})
else:
image_md_chunk += f"**Image {extracted_pil_images_overall_count} (not uploaded due to missing HF_TOKEN)**\n"
if ocr_text:
image_md_chunk += f"**OCR Text (from PDF Page {current_pdf_page_num}):**\n```\n{ocr_text}\n```\n\n"
else:
image_md_chunk += f"_(No text detected by OCR for image from PDF page {current_pdf_page_num})_\n\n"
yield yield_message("image_md", {"content": image_md_chunk})
time.sleep(0.01)
except Exception as e_img_info:
logger.error(f"Could not get PDF info for image batching or during batched conversion: {e_img_info}", exc_info=True)
yield yield_message("error", {"message": f"Error preparing for image extraction: {e_img_info}. Trying bulk conversion."})
# Fallback to bulk conversion
bulk_images_pil = []
if is_input_bytes:
bulk_images_pil = convert_from_bytes(actual_pdf_input_for_images, dpi=150)
else:
bulk_images_pil = convert_from_path(actual_pdf_input_for_images, dpi=150)
yield yield_message("status", {"message": f"Fallback: Converted {len(bulk_images_pil)} PDF pages to images in bulk."})
for i, img_pil in enumerate(bulk_images_pil):
extracted_pil_images_overall_count +=1
page_num_for_log = f"bulk_image_{i+1}"
yield yield_message("status", {"message": f"Processing image {extracted_pil_images_overall_count} (bulk page {i+1}) (OCR & Upload)..."})
ocr_text = ""
try: ocr_text = pytesseract.image_to_string(img_pil).strip()
except Exception as e: ocr_text = f"OCR Error: {e}"
image_md_chunk = f"### Image from PDF Page (Bulk {i+1})\n"
if HF_TOKEN:
image_url_or_error = upload_image_to_hf_stream(img_pil, "pdf_page_image_fallback", page_num_for_log)
if isinstance(image_url_or_error, str) and not image_url_or_error.startswith("Error"):
image_md_chunk += f"![Image {extracted_pil_images_overall_count} (Fallback)]({image_url_or_error})\n"
else:
image_md_chunk += f"**Upload Error:** {str(image_url_or_error)}\n"
else:
image_md_chunk += f"**Image {extracted_pil_images_overall_count} (Fallback - not uploaded)**\n"
if ocr_text: image_md_chunk += f"**OCR Text (Bulk Page {i+1}):**\n```\n{ocr_text}\n```\n\n"
else: image_md_chunk += f"_(No text detected by OCR for bulk image {i+1})_\n\n"
yield yield_message("image_md", {"content": image_md_chunk})
time.sleep(0.01)
else:
yield yield_message("status", {"message": "No valid PDF input source provided for image extraction."})
except Exception as e:
logger.error(f"Error during image extraction/OCR processing: {str(e)}", exc_info=True)
yield yield_message("error", {"message": f"Error during image extraction/OCR: {str(e)}"})
yield yield_message("final_status", {"message": "Image extraction and OCR processing complete."})
except Exception as e:
logger.error(f"Unhandled error in PDF conversion stream: {str(e)}", exc_info=True)
yield yield_message("error", {"message": f"Critical processing error: {str(e)}"})
# --- Flask Routes ---
@app.route('/', methods=['GET'])
def index():
return render_template('index.html')
@app.route('/process-stream', methods=['POST'])
def process_pdf_stream():
pdf_file = request.files.get('pdf_file')
pdf_url = request.form.get('pdf_url', '').strip()
outer_temp_pdf_path = None
def stream_processor():
nonlocal outer_temp_pdf_path
pdf_input_source_for_generator = None
try:
if pdf_file and pdf_file.filename:
if not pdf_file.filename.lower().endswith('.pdf'):
yield yield_message("error", {"message": "Uploaded file is not a PDF."})
return
filename = secure_filename(pdf_file.filename)
os.makedirs(app.config['UPLOAD_FOLDER'], exist_ok=True)
# Save to a temporary file that generate_pdf_conversion_stream can access by path
fd, temp_path = tempfile.mkstemp(suffix=".pdf", prefix="upload_", dir=app.config['UPLOAD_FOLDER'])
os.close(fd) # Close the file descriptor from mkstemp
pdf_file.save(temp_path) # Save the uploaded file's content to this path
outer_temp_pdf_path = temp_path # Store for cleanup
logger.info(f"Uploaded PDF saved to temporary path: {outer_temp_pdf_path}")
pdf_input_source_for_generator = outer_temp_pdf_path # Pass the path
yield yield_message("status", {"message": f"Processing uploaded PDF: {filename}"})
time.sleep(0.01)
elif pdf_url:
unquoted_url = urllib.parse.unquote(pdf_url)
if not (unquoted_url.startswith('http://') or unquoted_url.startswith('https://')):
yield yield_message("error", {"message": "Invalid URL scheme. Must be http or https."})
return
pdf_input_source_for_generator = unquoted_url # Pass the URL string
yield yield_message("status", {"message": f"Preparing to process PDF from URL: {unquoted_url}"})
time.sleep(0.01)
else:
yield yield_message("error", {"message": "No PDF file uploaded and no PDF URL provided."})
return
for message_part in generate_pdf_conversion_stream(pdf_input_source_for_generator):
yield message_part
except Exception as e:
logger.error(f"Error setting up stream or in initial validation: {str(e)}", exc_info=True)
yield yield_message("error", {"message": f"Setup error: {str(e)}"})
finally:
if outer_temp_pdf_path and os.path.exists(outer_temp_pdf_path):
try:
os.remove(outer_temp_pdf_path)
logger.info(f"Cleaned up temporary PDF: {outer_temp_pdf_path}")
except OSError as ose:
logger.error(f"Error removing temporary PDF {outer_temp_pdf_path}: {ose}")
return Response(stream_with_context(stream_processor()), mimetype='application/x-ndjson')
# --- Main Execution ---
if __name__ == '__main__':
if not check_poppler():
logger.warning("Poppler utilities might not be installed correctly. Image processing might fail.")
os.makedirs(app.config['UPLOAD_FOLDER'], exist_ok=True)
app.run(host='0.0.0.0', port=int(os.getenv("PORT", 7860)), debug=True, threaded=True)