#!/usr/bin/env python3
import os
import requests
import logging
import mimetypes
import json
from celery import shared_task
from app.config import settings
from app.tasks.process_document import process_document
logger = logging.getLogger(__name__)
@shared_task
def convert_to_pdf(file_path):
"""
Converts a file to PDF using Gotenberg's API.
Determines the appropriate Gotenberg endpoint based on the file's MIME type.
On success, saves the PDF locally and enqueues it for processing.
"""
gotenberg_url = getattr(settings, "gotenberg_url", None)
if not gotenberg_url:
logger.error("Gotenberg URL is not configured in settings.")
return
# Try to guess the MIME type based on file content and extension
mime_type, encoding = mimetypes.guess_type(file_path)
file_ext = os.path.splitext(file_path)[1].lower()
logger.info(f"Guessed MIME type for '{file_path}' is: {mime_type}, extension: {file_ext}")
# Determine which Gotenberg endpoint to use
endpoint = None
form_data = {}
files = {}
# Dictionary mapping file extensions to their handlers
OFFICE_EXTENSIONS = {
'.doc', '.docx', '.docm', '.dot', '.dotx', '.dotm', # Word
'.xls', '.xlsx', '.xlsm', '.xlsb', '.xlt', '.xltx', '.xlw', # Excel
'.ppt', '.pptx', '.pptm', '.pps', '.ppsx', '.pot', '.potx', # PowerPoint
'.odt', '.ods', '.odp', '.odg', '.odf', # OpenOffice/LibreOffice
'.rtf', '.txt', '.csv', # Text formats
'.pdf', # PDF (already in PDF format but can be processed)
}
IMAGE_EXTENSIONS = {
'.jpg', '.jpeg', '.png', '.gif', '.bmp', '.tiff', '.tif', '.webp', '.svg'
}
HTML_EXTENSIONS = {
'.html', '.htm'
}
# Use LibreOffice endpoint for office documents and images
if (mime_type and 'office' in mime_type) or \
(mime_type and 'opendocument' in mime_type) or \
(mime_type and mime_type.startswith('image/')) or \
file_ext in OFFICE_EXTENSIONS or \
file_ext in IMAGE_EXTENSIONS:
endpoint = f"{gotenberg_url}/forms/libreoffice/convert"
files = {'files': (os.path.basename(file_path), open(file_path, 'rb'))}
# Add some quality settings for better PDF output
form_data = {
'landscape': 'false',
'exportBookmarks': 'true',
'exportNotes': 'false',
'losslessImageCompression': 'true', # Use lossless compression for images
'pdfa': 'PDF/A-2b', # Produce PDF/A-2b compatible output
}
# Use Chromium endpoint for HTML documents
elif (mime_type and mime_type == 'text/html') or file_ext in HTML_EXTENSIONS:
endpoint = f"{gotenberg_url}/forms/chromium/convert/html"
# Gotenberg requires the form field to be exactly 'index.html'
# The content filename doesn't matter, just the form field key
files = {'index.html': ('index.html', open(file_path, 'rb'))}
# Add options for better HTML to PDF conversion
form_data = {
'paperWidth': '8.27', # A4 width in inches
'paperHeight': '11.7', # A4 height in inches
'marginTop': '0.4',
'marginBottom': '0.4',
'marginLeft': '0.4',
'marginRight': '0.4',
'printBackground': 'true',
'preferCssPageSize': 'false',
'waitDelay': '2s', # Wait for JavaScript to execute
}
# Use Markdown route for markdown files
elif (mime_type and mime_type in ['text/markdown', 'text/x-markdown']) or file_ext in ['.md', '.markdown']:
# For Markdown, we need both the markdown file and an HTML wrapper
endpoint = f"{gotenberg_url}/forms/chromium/convert/markdown"
# Create a simple HTML wrapper for the markdown
# IMPORTANT: The filename in the template must match the key used in the files dictionary
markdown_filename = os.path.basename(file_path)
html_wrapper = f"""
Converted Markdown
{{{{ toHTML "{markdown_filename}" }}}}
"""
# Create a temporary HTML wrapper file
wrapper_path = os.path.join(os.path.dirname(file_path), "md_wrapper.html")
with open(wrapper_path, 'w') as f:
f.write(html_wrapper)
try:
files = {
'index.html': ('index.html', open(wrapper_path, 'rb')),
markdown_filename: (markdown_filename, open(file_path, 'rb'))
}
form_data = {
'paperWidth': '8.27', # A4 width in inches
'paperHeight': '11.7', # A4 height in inches
'marginTop': '0.4',
'marginBottom': '0.4',
'marginLeft': '0.4',
'marginRight': '0.4',
}
finally:
# Clean up the temporary wrapper file after preparing the request
if os.path.exists(wrapper_path):
os.remove(wrapper_path)
# Fallback to LibreOffice for everything else
else:
endpoint = f"{gotenberg_url}/forms/libreoffice/convert"
files = {'files': (os.path.basename(file_path), open(file_path, 'rb'))}
logger.warning(f"Using fallback conversion for unknown type: {mime_type} / {file_ext}")
if not endpoint:
logger.error(f"Could not determine Gotenberg endpoint for file type: {mime_type}")
return None
try:
logger.info(f"Converting {file_path} using endpoint: {endpoint}")
# Send the conversion request to Gotenberg
response = requests.post(endpoint, files=files, data=form_data)
if response.status_code == 200:
# Save the converted PDF
converted_file_path = os.path.splitext(file_path)[0] + ".pdf"
with open(converted_file_path, "wb") as out_file:
out_file.write(response.content)
logger.info(f"Converted file saved as PDF: {converted_file_path}")
# Enqueue the PDF for further processing
process_document.delay(converted_file_path)
return converted_file_path
else:
logger.error(
f"Conversion failed for {file_path}. "
f"Status code: {response.status_code}, "
f"Response: {response.text[:500]}..."
)
return None
except Exception as e:
logger.exception(f"Error converting {file_path} to PDF: {e}")
return None