extract_invalid_emails.py

#!/usr/bin/python
# extract_invalid_emails.py
#  Given a file as argument or STDIN, only print lines with invalid emails


### http://tfletcher.com/lib/rfc822.py >>>
#
# RFC822 Email Address Regex
# --------------------------
# 
# Originally written by Cal Henderson
# c.f. http://iamcal.com/publish/articles/php/parsing_email/
#
# Translated to Python by Tim Fletcher, with changes suggested by Dan Kubb.
#
# Licensed under a Creative Commons Attribution-ShareAlike 2.5 License
# http://creativecommons.org/licenses/by-sa/2.5/
# 
import os
import re
import sys

qtext = '[^\\x0d\\x22\\x5c\\x80-\\xff]'
dtext = '[^\\x0d\\x5b-\\x5d\\x80-\\xff]'
atom = '[^\\x00-\\x20\\x22\\x28\\x29\\x2c\\x2e\\x3a-\\x3c\\x3e\\x40\\x5b-\\x5d\\x7f-\\xff]+'
quoted_pair = '\\x5c[\\x00-\\x7f]'
domain_literal = "\\x5b(?:%s|%s)*\\x5d" % (dtext, quoted_pair)
quoted_string = "\\x22(?:%s|%s)*\\x22" % (qtext, quoted_pair)
domain_ref = atom
sub_domain = "(?:%s|%s)" % (domain_ref, domain_literal)
word = "(?:%s|%s)" % (atom, quoted_string)
domain = "%s(?:\\x2e%s)*" % (sub_domain, sub_domain)
local_part = "%s(?:\\x2e%s)*" % (word, word)
addr_spec = "%s\\x40%s" % (local_part, domain)


email_address = re.compile('\A%s\Z' % addr_spec)

### END <<<

if len(sys.argv) > 1 and os.path.exists(sys.argv[1]):
    fh = open(sys.argv[1])
else:
    fh = sys.stdin

if __name__ == '__main__':
   for line in fh:
       if not email_address.match(line.strip()):
            sys.stdout.write(line)