This snippet parses a css file thru csstyle module, finds the external links, download them, save locally, fixes the css file to point to new paths and also prettifies the css

turn-css-file-links-into-locals.py

#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
# This snippet parses a css file thru csstyle module, finds the
# external links, download them, save locally, fixes the css
# file to point to new paths and also prettifies the css
#
# example of usage:
# find . -iname '*.css' | cut -d: -f1 | uniq | egrep -v '[.]html' | xargs turn-css-file-links-into-locals.py 2>&1 >> css-hacks.log
# 
# Copyright (C) <2011>  Gabriel Falcão <[email protected]>
#
# Permission is hereby granted, free of charge, to any person
# obtaining a copy of this software and associated documentation
# files (the "Software"), to deal in the Software without
# restriction, including without limitation the rights to use,
# copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the
# Software is furnished to do so, subject to the following
# conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
# OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
# HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
# WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
# OTHER DEALINGS IN THE SOFTWARE.

import os
import re
import sys
try:
    import hashlib
except ImportError:
    print "this script supports only python 2.6 or later"
    sys.exit(1)

import urllib2
try:
    import csstyle
except ImportError:
    print "missing the module csstyle, please install thru 'pip install csstyle'"
    sys.exit(1)

from urlparse import urlsplit
from os.path import abspath, join, exists, split, relpath, dirname

URL_REGEX = ur'url[(][\'"]?(?P<link>http[^)]+)[\'"]?[)]'
class CSSFixer(object):
    def __init__(self, *paths):
        self.paths = map(abspath, paths)
        self.regex = re.compile(URL_REGEX, re.U | re.I)

    def fix_one_file(self, path):
        print "parsing %s" % path
        try:
            p = csstyle.Parser(filenames=[abspath(path)])
        except ValueError:
            print "      failed to parse %s" % path
            return

        only_urls_from = lambda x: 'url' in x[1].lower()

        for selector, defs in p.items():
            for key, value in defs.items():
                matched = self.regex.search(value)
                if not matched:
                    continue

                url = matched.group('link')
                info = urlsplit(url)
                folder = join(abspath(dirname(path)), hashlib.md5(info.netloc).hexdigest())
                destination = join(folder, split(info.path)[-1])
                local_path = relpath(destination)
                defs[key] = self.regex.sub('url(%s)' % local_path, value)

                if exists(destination):
                    print "      ignoring %s since it's already on %s" % (url, local_path)
                    continue

                if not exists(folder):
                    os.makedirs(folder)

                try:
                    ld = urllib2.urlopen(url)
                except Exception, e:
                    if hasattr(e, 'code') and e.code not in (200, 304):
                        print "      got %d on %s and it was ignored" % (e.code, url)
                    else:
                        print e

                    continue

                bin = ld.read()
                ld.close()

                fd = open(destination, 'w')
                fd.write(bin)
                fd.close()
                print "    wrote on %s" % local_path


        open(path, 'w').write(unicode(p))
        print "%s was successfully fixed" % path

    def fix_them_all(self):
        map(self.fix_one_file, self.paths)

if __name__ == '__main__':
    if len(sys.argv) == 1:
        print 'usage: %s path/to/filename.css another/path.css ... /and/so/on.css' % sys.argv[0]
        sys.exit(1)

    transformer = CSSFixer(*sys.argv[1:])
    transformer.fix_them_all()