import sgmllib, string
class StrippingParser(sgmllib.SGMLParser):
# These are the HTML tags that we will leave intact
valid_tags = ('b', 'a', 'i', 'br', 'p')
from htmlentitydefs import entitydefs # replace entitydefs from sgmllib
def __init__(self):
sgmllib.SGMLParser.__init__(self)
self.result = ""
self.endTagList = []
def handle_data(self, data):
if data:
self.result = self.result + data
def handle_charref(self, name):
self.result = "%s&#%s;" % (self.result, name)
def handle_entityref(self, name):
if self.entitydefs.has_key(name):
x = ';'
else:
# this breaks unstandard entities that end with ';'
x = ''
self.result = "%s&%s%s" % (self.result, name, x)
def unknown_starttag(self, tag, attrs):
""" Delete all tags except for legal ones """
if tag in self.valid_tags:
self.result = self.result + '<' + tag
for k, v in attrs:
if string.lower(k[0:2]) != 'on' and string.lower(v[0:10]) != 'javascript':
self.result = '%s %s="%s"' % (self.result, k, v)
endTag = '</%s>' % tag
self.endTagList.insert(0,endTag)
self.result = self.result + '>'
def unknown_endtag(self, tag):
if tag in self.valid_tags:
self.result = "%s</%s>" % (self.result, tag)
remTag = '</%s>' % tag
self.endTagList.remove(remTag)
def cleanup(self):
""" Append missing closing tags """
for j in range(len(self.endTagList)):
self.result = self.result + self.endTagList[j]
def strip(s):
""" Strip illegal HTML tags from string s """
parser = StrippingParser()
parser.feed(s)
parser.close()
parser.cleanup()
return parser.result
