lib.py

import tokenize
import token
from io import StringIO


def fix_lazy_json (in_text):
  tokengen = tokenize.generate_tokens(StringIO(in_text).readline)

  result = []
  for tokid, tokval, _, _, _ in tokengen:
    # fix unquoted strings
    if (tokid == token.NAME):
      if tokval not in ['true', 'false', 'null', '-Infinity', 'Infinity', 'NaN']:
        tokid = token.STRING
        tokval = u'"%s"' % tokval

    # fix single-quoted strings
    elif (tokid == token.STRING):
      if tokval.startswith ("'"):
        tokval = u'"%s"' % tokval[1:-1].replace ('"', '\\"')

    # remove invalid commas
    elif (tokid == token.OP) and ((tokval == '}') or (tokval == ']')):
      if (len(result) > 0) and (result[-1][1] == ','):
        result.pop()

    # fix single-quoted strings
    elif (tokid == token.STRING):
      if tokval.startswith ("'"):
        tokval = u'"%s"' % tokval[1:-1].replace ('"', '\\"')

    result.append((tokid, tokval))

  return tokenize.untokenize(result)