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'''
Parent class of all parser
'''
import hachoir_core
import hachoir_editor
import os
import mat
NOMETA = ('.bmp', '.rdf', '.txt', '.xml', '.rels')
#bmp : image
#rdf : text
#txt : plain text
#xml : formated text
#rels : openxml foramted text
class GenericParser(object):
'''
Parent class of all parsers
'''
def __init__(self, filename, parser, mime, backup, add2archive):
self.filename = ''
self.parser = parser
self.mime = mime
self.backup = backup
self.editor = hachoir_editor.createEditor(parser)
self.realname = filename
try:
self.filename = hachoir_core.cmd_line.unicodeFilename(filename)
except TypeError: # get rid of "decoding Unicode is not supported"
self.filename = filename
basename, ext = os.path.splitext(filename)
self.output = basename + '.cleaned' + ext
self.basename = os.path.basename(filename) # only filename
def is_clean(self):
'''
Check if the file is clean from harmful metadatas
'''
for field in self.editor:
if self._should_remove(field):
return False
return True
def remove_all(self):
'''
Remove all the files that are compromizing
'''
for field in self.editor:
if self._should_remove(field):
self._remove(field.name)
hachoir_core.field.writeIntoFile(self.editor, self.output)
self.do_backup()
def remove_all_ugly(self):
'''
If the remove_all() is not efficient enough,
this method is implemented :
It is efficient, but destructive.
In a perfect world, with nice fileformat,
this method would not exist.
'''
self.remove_all()
def _remove(self, field):
'''
Delete the given field
'''
del self.editor[field]
def get_meta(self):
'''
Return a dict with all the meta of the file
'''
metadata = {}
for field in self.editor:
if self._should_remove(field):
try:
metadata[field.name] = field.value
except:
metadata[field.name] = 'harmful content'
return metadata
def _should_remove(self, key):
'''
return True if the field is compromizing
abstract method
'''
raise NotImplementedError
def do_backup(self):
'''
Do a backup of the file if asked,
and change his creation/access date
'''
if self.backup is True:
os.utime(self.output, (0, 0))
else:
mat.secure_remove(self.filename)
os.rename(self.output, self.filename)
os.utime(self.filename, (0, 0))
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