css_split.py

# -*- coding: utf-8 -*-

import re
import os.path
import glob
import argparse
parser = argparse.ArgumentParser(description='split css')
parser.add_argument('css', help='css file')
parser.add_argument('index', help='index file')

args = parser.parse_args()

css_file = glob.glob(args.css)[0]
base, ext = os.path.splitext(css_file)

with open(css_file) as f:
    rules = re.findall(r'[^\{]+\{[^\}]*\}', f.read(), re.MULTILINE)

print 'Number of rules: ', len(rules)

def chunker(seq, size):
    return (seq[pos:pos + size] for pos in range(0, len(seq), size))

i = 0
for sub_rules in chunker(rules, 4096):
    with open(base + '-' + str(i) + ".css", 'w') as f:
        f.write('\n'.join(sub_rules))
        i += 1


with open(args.index) as f:
    rewrite = f.read()
with open(args.index, 'w') as f:
    for l in rewrite.split('\n'):
        if '<link' in l:
            a, b = l.split('.css')
            for j in range(i):
                f.write(a + '-' + str(j) + '.css' + b + '\n')
        else:
            f.write(l + '\n')