manage_html.py

import re

from django.utils.safestring import mark_safe


def strip(s, all_tags=None):
    try:
        from BeautifulSoup import BeautifulSoup, Comment
        soup = BeautifulSoup(s)
    except ImportError:
        soup = None

    valid_tags = ('strong b a i'.split() if not all_tags else '')
    valid_attrs = ('href src'.split() if not all_tags else '')

    if soup:
        for Comment in soup.findAll(
            text=lambda text: isinstance(text, Comment)):
            comment.extract()
        for tag in soup.findAll(True):
            if tag.name not in valid_tags:
                tag.hidden = True
            tag.attrs = [(attr, val) for attr, val in tag.attrs
                        if attr in valid_attrs]
        ret = soup.renderContents().decode('utf8').replace('javascript:', '')
    else:
        ret = "Could not load BeautifulSoup"

    return ret

def convert_links(s):
    #NOTE: TEXT MUST ALREDY BE ESCAPED...
    ##Find links that aren't already active (hyperlinked) and turn into hyperlink
    URL_regex = re.compile(r'(|^)http([\w\d\.\:\/]+?)(\s|$|\:|,)', re.IGNORECASE)
    s = URL_regex.sub(r'\1<a href="http\2">http\2</a>\3', s)

    URL_regex = re.compile(r'(\s|^)@([\w\d_]+)', re.IGNORECASE)
    s = URL_regex.sub(r'\1<a href="http://twitter.com/\2/">@\2</a>', s)
    return mark_safe(s)