sw.py

#!/usr/bin/env python

import os
import re, sys

if __name__ == '__main__':

  contents = ''

  cwd = os.path.dirname(os.path.abspath(sys.argv[0]))
  print(cwd)
  dist_dir = os.path.join(cwd, 'client/dist')
  print (dist_dir)
  sw_js = 'sw.js'
  with open(os.path.join(dist_dir, sw_js), 'r') as swjs:
    contents = swjs.read()
    js_re = r'\..*\.bundle\.js'
    results = re.findall(js_re, contents)

    for r in [x for x in results if x.strip() != '']:
      root = r.split('.bundle.js')[0]
      root = root[2:].strip()
      suffix = '.js'
      if root == 'styles':
        suffix = '.css'
      match = [a for a in os.listdir(dist_dir) if a.startswith(root) and a.endswith(suffix)][0]
      find = r
      replace = './' + match
      print(find, '=>', replace)
      contents = contents.replace(find, replace)

  with (open(os.path.join(dist_dir, sw_js), 'w')) as swjs:
    swjs.write(contents)