Problem with unicode literals and EMAIL_PORT

[Michal Čihař]

When your settings.py looks like:

from __future__ import unicode_literals
EMAIL_HOST= 'localhost'
EMAIL_PORT = '587'

You end up with error when sending mail:

File "/opt/weblate/.local/lib/python2.7/site-packages/django/core/mail/backends/smtp.py" in open
  58.             self.connection = connection_class(self.host, self.port, **connection_params)

File "/usr/lib/python2.7/smtplib.py" in __init__
  256.             (code, msg) = self.connect(host, port)

File "/usr/lib/python2.7/smtplib.py" in connect
  316.         self.sock = self._get_socket(host, port, self.timeout)

File "/usr/lib/python2.7/smtplib.py" in _get_socket
  291.         return socket.create_connection((host, port), timeout)

File "/usr/lib/python2.7/socket.py" in create_connection
  553.     for res in getaddrinfo(host, port, 0, SOCK_STREAM):

Exception Type: error at /accounts/register/
Exception Value: getaddrinfo() argument 2 must be integer or string

This is caused by fact that that getaddrinfo happily accepts int or string, but not unicode literals as port (it doesn't have problem with unicode literals as hostname though):

>>> from __future__ import unicode_literals
>>> import socket
>>> socket.getaddrinfo('localhost', '567', 0, socket.SOCK_STREAM)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
socket.error: getaddrinfo() argument 2 must be integer or string

I think Django should prevent this configuration error, or at least properly tell where the problem is.

Originally reported at ​https://github.com/WeblateOrg/weblate/issues/1330

[Tim Graham]

Python 2 specific issues are now obsolete as Django 1.11 will be the last version to support it and master now targets Django 2.0.