Python Regexp To Match E-mail Against Domain Names

I'm looking for the 'perfect' regexp's to validate if an e-mail belongs to a domain name (including sub-domains), for example: www.domain.com : some1@domain.com sub.domain.com : so

Solution 1:

Taken from django:

email_re = re.compile(
    r"(^[-!#$%&'*+/=?^_`{}|~0-9A-Z]+(\.[-!#$%&'*+/=?^_`{}|~0-9A-Z]+)*"  # dot-atom
    r'|^"([\001-\010\013\014\016-\037!#-\[\]-\177]|\\[\001-011\013\014\016-\177])*"' # quoted-string
    r')@(?:[A-Z0-9](?:[A-Z0-9-]{0,61}[A-Z0-9])?\.)+[A-Z]{2,6}\.?$', re.IGNORECASE)  # domain

Solution 2:

You don't need a regex:

>>> def match_domain(domain, email):
...    return email.endswith(domain.lstrip('www.'))
...
>>> match_domain('www.domain.com', 'some1@domain.com')
True
>>> match_domain('www.domain.com', 'some1@www.domain.com')
True
>>> match_domain('sub.domain.com', 'some1@sub.domain.com')
True
>>> match_domain('sub.domain2.com', 'some1@sub.domain.com')
False
>>> match_domain('domain2.com', 'some1@domain.com')
False