dangerzone/container/dangerzone.py
2021-11-29 15:39:24 -08:00

541 lines
17 KiB
Python

#!/usr/bin/env python3
"""
Here are the steps, with progress bar percentages for each step:
document_to_pixels
- 0%-3%: Convert document into a PDF (skipped if the input file is a PDF)
- 3%-5%: Split PDF into individual pages, and count those pages
- 5%-50%: Convert each page into pixels (each page takes 45/n%, where n is the number of pages)
pixels_to_pdf:
- 50%-95%: Convert each page of pixels into a PDF (each page takes 45/n%, where n is the number of pages)
- 95%-100%: Compress the final PDF
"""
import sys
import subprocess
import glob
import os
import json
import shutil
import magic
from PIL import Image
class DangerzoneConverter:
def __init__(self):
pass
def document_to_pixels(self):
percentage = 0.0
conversions = {
# .pdf
"application/pdf": {"type": None},
# .docx
"application/vnd.openxmlformats-officedocument.wordprocessingml.document": {
"type": "libreoffice",
"libreoffice_output_filter": "writer_pdf_Export",
},
# .doc
"application/msword": {
"type": "libreoffice",
"libreoffice_output_filter": "writer_pdf_Export",
},
# .docm
"application/vnd.ms-word.document.macroEnabled.12": {
"type": "libreoffice",
"libreoffice_output_filter": "writer_pdf_Export",
},
# .xlsx
"application/vnd.openxmlformats-officedocument.spreadsheetml.sheet": {
"type": "libreoffice",
"libreoffice_output_filter": "calc_pdf_Export",
},
# .xls
"application/vnd.ms-excel": {
"type": "libreoffice",
"libreoffice_output_filter": "calc_pdf_Export",
},
# .pptx
"application/vnd.openxmlformats-officedocument.presentationml.presentation": {
"type": "libreoffice",
"libreoffice_output_filter": "impress_pdf_Export",
},
# .ppt
"application/vnd.ms-powerpoint": {
"type": "libreoffice",
"libreoffice_output_filter": "impress_pdf_Export",
},
# .odt
"application/vnd.oasis.opendocument.text": {
"type": "libreoffice",
"libreoffice_output_filter": "writer_pdf_Export",
},
# .odg
"application/vnd.oasis.opendocument.graphics": {
"type": "libreoffice",
"libreoffice_output_filter": "impress_pdf_Export",
},
# .odp
"application/vnd.oasis.opendocument.presentation": {
"type": "libreoffice",
"libreoffice_output_filter": "impress_pdf_Export",
},
# .ops
"application/vnd.oasis.opendocument.spreadsheet": {
"type": "libreoffice",
"libreoffice_output_filter": "calc_pdf_Export",
},
# .jpg
"image/jpeg": {"type": "convert"},
# .gif
"image/gif": {"type": "convert"},
# .png
"image/png": {"type": "convert"},
# .tif
"image/tiff": {"type": "convert"},
"image/x-tiff": {"type": "convert"},
}
# Detect MIME type
mime = magic.Magic(mime=True)
mime_type = mime.from_file("/tmp/input_file")
# Validate MIME type
if mime_type not in conversions:
self.output(True, "The document format is not supported", percentage)
return 1
# Convert input document to PDF
conversion = conversions[mime_type]
if conversion["type"] is None:
pdf_filename = "/tmp/input_file"
elif conversion["type"] == "libreoffice":
self.output(False, "Converting to PDF using LibreOffice", percentage)
args = [
"libreoffice",
"--headless",
"--convert-to",
f"pdf:{conversion['libreoffice_output_filter']}",
"--outdir",
"/tmp",
"/tmp/input_file",
]
try:
p = subprocess.run(
args,
stdout=subprocess.DEVNULL,
stderr=subprocess.DEVNULL,
timeout=60,
)
except subprocess.TimeoutExpired:
self.output(
True,
"Error converting document to PDF, LibreOffice timed out after 60 seconds",
percentage,
)
return 1
if p.returncode != 0:
self.output(
True,
f"Conversion to PDF with LibreOffice failed",
percentage,
)
return 1
pdf_filename = "/tmp/input_file.pdf"
elif conversion["type"] == "convert":
self.output(False, "Converting to PDF using GraphicsMagick", percentage)
args = [
"gm",
"convert",
"/tmp/input_file",
"/tmp/input_file.pdf",
]
try:
p = subprocess.run(
args,
stdout=subprocess.DEVNULL,
stderr=subprocess.DEVNULL,
timeout=60,
)
except subprocess.TimeoutExpired:
self.output(
True,
"Error converting document to PDF, GraphicsMagick timed out after 60 seconds",
percentage,
)
return 1
if p.returncode != 0:
self.output(
True,
"Conversion to PDF with GraphicsMagick failed",
percentage,
)
return 1
pdf_filename = "/tmp/input_file.pdf"
else:
self.output(
True,
"Invalid conversion type",
percentage,
)
return 1
percentage += 3
# Separate PDF into pages
self.output(
False,
"Separating document into pages",
percentage,
)
args = ["pdftk", pdf_filename, "burst", "output", "/tmp/page-%d.pdf"]
try:
p = subprocess.run(
args, stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL, timeout=60
)
except subprocess.TimeoutExpired:
self.output(
True,
"Error separating document into pages, pdfseparate timed out after 60 seconds",
percentage,
)
return 1
if p.returncode != 0:
self.output(
True,
"Separating document into pages failed",
percentage,
)
return 1
page_filenames = glob.glob("/tmp/page-*.pdf")
percentage += 2
# Convert to RGB pixel data
percentage_per_page = 45.0 / len(page_filenames)
for page in range(1, len(page_filenames) + 1):
pdf_filename = f"/tmp/page-{page}.pdf"
png_filename = f"/tmp/page-{page}.png"
rgb_filename = f"/tmp/page-{page}.rgb"
width_filename = f"/tmp/page-{page}.width"
height_filename = f"/tmp/page-{page}.height"
filename_base = f"/tmp/page-{page}"
self.output(
False,
f"Converting page {page}/{len(page_filenames)} to pixels",
percentage,
)
# Convert to png
try:
p = subprocess.run(
["pdftocairo", pdf_filename, "-png", "-singlefile", filename_base],
stdout=subprocess.DEVNULL,
stderr=subprocess.DEVNULL,
timeout=60,
)
except subprocess.TimeoutExpired:
self.output(
True,
"Error converting from PDF to PNG, pdftocairo timed out after 60 seconds",
percentage,
)
return 1
if p.returncode != 0:
self.output(
True,
"Conversion from PDF to PNG failed",
percentage,
)
return 1
# Save the width and height
im = Image.open(png_filename)
width, height = im.size
with open(width_filename, "w") as f:
f.write(str(width))
with open(height_filename, "w") as f:
f.write(str(height))
# Convert to RGB pixels
try:
p = subprocess.run(
[
"gm",
"convert",
png_filename,
"-depth",
"8",
f"rgb:{rgb_filename}",
],
timeout=60,
)
except subprocess.TimeoutExpired:
self.output(
True,
"Error converting from PNG to pixels, convert timed out after 60 seconds",
percentage,
)
return 1
if p.returncode != 0:
self.output(
True,
"Conversion from PNG to RGB failed",
percentage,
)
return 1
# Delete the png
os.remove(png_filename)
percentage += percentage_per_page
self.output(
False,
"Converted document to pixels",
percentage,
)
# Move converted files into /dangerzone
for filename in (
glob.glob("/tmp/page-*.rgb")
+ glob.glob("/tmp/page-*.width")
+ glob.glob("/tmp/page-*.height")
):
shutil.move(filename, "/dangerzone")
return 0
def pixels_to_pdf(self):
percentage = 50.0
num_pages = len(glob.glob("/dangerzone/page-*.rgb"))
# Convert RGB files to PDF files
percentage_per_page = 45.0 / num_pages
for page in range(1, num_pages + 1):
filename_base = f"/dangerzone/page-{page}"
rgb_filename = f"{filename_base}.rgb"
width_filename = f"{filename_base}.width"
height_filename = f"{filename_base}.height"
png_filename = f"/tmp/page-{page}.png"
ocr_filename = f"/tmp/page-{page}"
pdf_filename = f"/tmp/page-{page}.pdf"
with open(width_filename) as f:
width = f.read().strip()
with open(height_filename) as f:
height = f.read().strip()
if os.environ.get("OCR") == "1":
# OCR the document
self.output(
False,
f"Converting page {page}/{num_pages} from pixels to searchable PDF",
percentage,
)
args = [
"gm",
"convert",
"-size",
f"{width}x{height}",
"-depth",
"8",
f"rgb:{rgb_filename}",
f"png:{png_filename}",
]
try:
p = subprocess.run(
args,
stdout=subprocess.DEVNULL,
stderr=subprocess.DEVNULL,
timeout=60,
)
except subprocess.TimeoutExpired:
self.output(
True,
"Error converting pixels to PNG, convert timed out after 60 seconds",
percentage,
)
return 1
if p.returncode != 0:
self.output(
True,
f"Page {page}/{num_pages} conversion to PNG failed",
percentage,
)
return 1
args = [
"tesseract",
png_filename,
ocr_filename,
"-l",
os.environ.get("OCR_LANGUAGE"),
"--dpi",
"70",
"pdf",
]
try:
p = subprocess.run(
args,
stdout=subprocess.DEVNULL,
stderr=subprocess.DEVNULL,
timeout=60,
)
except subprocess.TimeoutExpired:
self.output(
True,
"Error converting PNG to searchable PDF, tesseract timed out after 60 seconds",
percentage,
)
return 1
if p.returncode != 0:
self.output(
True,
f"Page {page}/{num_pages} OCR failed",
percentage,
)
return 1
else:
# Don't OCR
self.output(
False,
f"Converting page {page}/{num_pages} from pixels to PDF",
percentage,
)
args = [
"gm",
"convert",
"-size",
f"{width}x{height}",
"-depth",
"8",
f"rgb:{rgb_filename}",
f"pdf:{pdf_filename}",
]
try:
p = subprocess.run(
args,
stdout=subprocess.DEVNULL,
stderr=subprocess.DEVNULL,
timeout=60,
)
except subprocess.TimeoutExpired:
self.output(
True,
"Error converting RGB to PDF, convert timed out after 60 seconds",
percentage,
)
return 1
if p.returncode != 0:
self.output(
True,
f"Page {page}/{num_pages} conversion to PDF failed",
percentage,
)
return 1
percentage += percentage_per_page
# Merge pages into a single PDF
self.output(
False,
f"Merging {num_pages} pages into a single PDF",
percentage,
)
args = ["pdfunite"]
for page in range(1, num_pages + 1):
args.append(f"/tmp/page-{page}.pdf")
args.append(f"/tmp/safe-output.pdf")
try:
p = subprocess.run(
args, stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL, timeout=60
)
except subprocess.TimeoutExpired:
self.output(
True,
"Error merging pages into a single PDF, pdfunite timed out after 60 seconds",
percentage,
)
return 1
if p.returncode != 0:
self.output(
True,
"Merging pages into a single PDF failed",
percentage,
)
return 1
percentage += 2
# Compress
self.output(
False,
f"Compressing PDF",
percentage,
)
compress_timeout = num_pages * 3
try:
p = subprocess.run(
["ps2pdf", "/tmp/safe-output.pdf", "/tmp/safe-output-compressed.pdf"],
stdout=subprocess.DEVNULL,
stderr=subprocess.DEVNULL,
timeout=compress_timeout,
)
except subprocess.TimeoutExpired:
self.output(
True,
f"Error compressing PDF, ps2pdf timed out after {compress_timeout} seconds",
percentage,
)
return 1
if p.returncode != 0:
self.output(
True,
f"Compressing PDF failed",
percentage,
)
return 1
percentage = 100.0
self.output(False, "Safe PDF created", percentage)
# Move converted files into /safezone
shutil.move("/tmp/safe-output.pdf", "/safezone")
shutil.move("/tmp/safe-output-compressed.pdf", "/safezone")
return 0
def output(self, error, text, percentage):
print(json.dumps({"error": error, "text": text, "percentage": int(percentage)}))
sys.stdout.flush()
def main():
if len(sys.argv) != 2:
print(f"Usage: {sys.argv[0]} [document-to-pixels]|[pixels-to-pdf]")
return -1
converter = DangerzoneConverter()
if sys.argv[1] == "document-to-pixels":
return converter.document_to_pixels()
if sys.argv[1] == "pixels-to-pdf":
return converter.pixels_to_pdf()
return -1
if __name__ == "__main__":
sys.exit(main())