online-judge/judge/lxml_tree.py
2019-09-28 20:53:49 -04:00

60 lines
1.6 KiB
Python

import logging
from django.utils.safestring import SafeData, mark_safe
from lxml import html
from lxml.etree import ParserError, XMLSyntaxError
logger = logging.getLogger('judge.html')
class HTMLTreeString(SafeData):
def __init__(self, str):
try:
self._tree = html.fromstring(str, parser=html.HTMLParser(recover=True))
except (XMLSyntaxError, ParserError) as e:
if str and (not isinstance(e, ParserError) or e.args[0] != 'Document is empty'):
logger.exception('Failed to parse HTML string')
self._tree = html.Element('div')
def __getattr__(self, attr):
try:
return getattr(self._tree, attr)
except AttributeError:
return getattr(str(self), attr)
def __setattr__(self, key, value):
if key[0] == '_':
super(HTMLTreeString, self).__setattr__(key, value)
setattr(self._tree, key, value)
def __repr__(self):
return '<HTMLTreeString %r>' % str(self)
def __str__(self):
return mark_safe(html.tostring(self._tree, encoding='unicode'))
def __radd__(self, other):
return other + str(self)
def __add__(self, other):
return str(self) + other
def __getitem__(self, item):
return str(self)[item]
def __getstate__(self):
return str(self)
def __setstate__(self, state):
self._tree = html.fromstring(state)
@property
def tree(self):
return self._tree
def fromstring(str):
if isinstance(str, HTMLTreeString):
return str
return HTMLTreeString(str)