How can I get the recipients of an email using Python?

Question

Say I have an email as sample.eml and I would like to get a list of all the recipients on that email. Let's say it looks like this:

From: wayne@example.com
To: Person Man <person.man@example.com>, Fredrick Douglas <music.man@example.org>
Cc: Guido <bdfl@example.com>, FLUFL <barry@example.com>
Bcc: spanish.inquisition@example.com, The Dude <big.lebowski@example.net>
Subject: Testing email

This isn't a very fancy email, but I'm just trying to prove a point here, OK?

I can stick this in a Python script and parse the email:

from email.parser import BytesParser
from itertools import chain

msg = b'''
From: wayne@example.com
To: Person Man <person.man@example.com>, Fredrick Douglas <music.man@example.org>
Cc: Guido <bdfl@example.com>, FLUFL <barry@example.com>
Bcc: spanish.inquisition@example.com, The Dude <big.lebowski@example.net>
Subject: Testing email

This isn't a very fancy email, but I'm just trying to prove a point here, OK?
'''.strip()
email = BytesParser().parsebytes(msg)

for recipient in chain(email.get_all('to'), email.get_all('cc'), email.get_all('bcc')):
    print('Recipient is:', repr(recipient))

I would expect to see something like:

Recipient is: 'Person Man <person.man@example.com>'
Recipient is: 'Fredrick Douglas <music.man@example.org>'
Recipient is: 'Guido <bdfl@example.com>'
Recipient is: 'FLUFL <barry@example.com>'
Recipient is: 'spanish.inquisition@example.com'
Recipient is: 'The Dude <big.lebowski@example.net>'

Instead, I get this:

Recipient is: 'Person Man <person.man@example.com>, Fredrick Douglas <music.man@example.org>'
Recipient is: 'Guido <bdfl@example.com>, FLUFL <barry@example.com>'
Recipient is: 'spanish.inquisition@example.com, The Dude <big.lebowski@example.net>'

Is there a better way to do this?

Answer 1

The best way I've found so far involves email.utils.

for recipient in getaddresses(
    chain(email.get_all('to', []), email.get_all('cc', []), email.get_all('bcc', []))
):
    print('The recipient is: ', recipient)

From the docs on getaddresses:

This method returns a list of 2-tuples of the form returned by parseaddr(). fieldvalues is a sequence of header field values as might be returned by Message.get_all.

get_all will return None if the header is absent, unless you pass in a default, so get_all('to', []) is a good idea.

This message has the added advantage of properly parsing some very terrible, but entirely valid, email addresses:

msg = b"""
From: wayne@example.com
To: Person Man <person.man@example.com>, Fredrick Douglas <music.man@example.org>
Cc: Guido <bdfl@example.com>, FLUFL <barry@example.com> ,"Abc\@def"@example.com ,"Fred Bloggs"@example.com ,"Joe\\Blow"@example.com ,"Abc@def"@example.com ,customer/department=shipping@example.com ,\$A12345@example.com ,!def!xyz%abc@example.com ,_somename@example.com, much."more\ unusual"@example.com, very.unusual."@".unusual.com@example.com, very."(),:;<>[]".VERY."very@\\"very".unusual@strange.example.com
Subject: Testing email

This isn't a very fancy email, but I'm just trying to prove a point here, OK?
""".strip()

Just splitting on , wouldn't correctly handle:

very."(),:;<>[]".VERY."very@\\"very".unusual@strange.example.com

Which is an entirely valid email address.