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""" Care about office's formats
"""
import logging
import os
import shutil
import tempfile
import xml.dom.minidom as minidom
import zipfile
try:
import cairo
import gi
gi.require_version('Poppler', '0.18')
from gi.repository import Poppler
except ImportError:
logging.info('office.py loaded without PDF support')
from libmat import parser
#from libmat import archive
class PdfStripper(parser.GenericParser):
""" Represent a PDF file
"""
def __init__(self, filename, mime, backup, is_writable, **kwargs):
super(PdfStripper, self).__init__(filename, mime, backup, is_writable, **kwargs)
self.uri = 'file://' + os.path.abspath(self.filename)
self.password = None
try:
self.pdf_quality = kwargs['low_pdf_quality']
except KeyError:
self.pdf_quality = False
self.meta_list = frozenset(['title', 'author', 'subject',
'keywords', 'creator', 'producer', 'metadata'])
def is_clean(self):
""" Check if the file is clean from harmful metadatas
"""
document = Poppler.Document.new_from_file(self.uri, self.password)
return not any(document.get_property(key) for key in self.meta_list)
def remove_all(self):
""" Opening the PDF with poppler, then doing a render
on a cairo pdfsurface for each pages.
http://cairographics.org/documentation/pycairo/2/
The use of an intermediate tempfile is necessary because
python-cairo segfaults on unicode.
See http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=699457
"""
document = Poppler.Document.new_from_file(self.uri, self.password)
try:
output = tempfile.mkstemp()[1]
# Size doesn't matter (pun intended),
# since the surface will be resized before
# being rendered
surface = cairo.PDFSurface(output, 10, 10)
context = cairo.Context(surface) # context draws on the surface
logging.debug('PDF rendering of %s', self.filename)
for pagenum in range(document.get_n_pages()):
page = document.get_page(pagenum)
page_width, page_height = page.get_size()
surface.set_size(page_width, page_height)
context.save()
if self.pdf_quality: # this may reduce the produced PDF size
page.render(context)
else:
page.render_for_printing(context)
context.restore()
context.show_page() # draw context on surface
surface.finish()
shutil.move(output, self.output)
except:
logging.error('Something went wrong when cleaning %s.', self.filename)
return False
try:
# For now, cairo cannot write meta, so we must use pdfrw
# See the realted thread: http://lists.cairographics.org/archives/cairo/2007-September/011466.html
import pdfrw
logging.debug('Removing %s\'s superficial metadata', self.filename)
trailer = pdfrw.PdfReader(self.output)
trailer.Info.Producer = None
trailer.Info.Creator = None
writer = pdfrw.PdfWriter()
writer.trailer = trailer
writer.write(self.output)
self.do_backup()
except:
logging.error('Unable to remove all metadata from %s, please install pdfrw', self.output)
return False
return True
def get_meta(self):
""" Return a dict with all the meta of the file
"""
document = Poppler.Document.new_from_file(self.uri, self.password)
metadata = {}
for key in self.meta_list:
if document.get_property(key):
metadata[key] = document.get_property(key)
return metadata
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