braveulysses

def sanitize(untrusted_html, additional_tags=None):
    """Strips potentially harmful tags and attributes from HTML, but preserves 
    all tags in a whitelist.
    
    Passing the list additional_tags will add the specified tags to the whitelist.
    
    The sanitizer does NOT encode reserved characters into XML entities.  It is up 
    to the template code, if any, to take care of that.
    
    Based on the work of:

braveulysses

def strip(untrusted_html):
    """Strips out all tags from untrusted_html, leaving only text.

    Converts XML entities to Unicode characters.  This is desirable because it 
    reduces the likelihood that a filter further down the text processing chain 
    will double-encode the XML entities."""
    soup = BeautifulStoneSoup(untrusted_html, convertEntities=BeautifulStoneSoup.ALL_ENTITIES)
    safe_html = ''.join(soup.findAll(text=True))
    return safe_html