ssl.SSLEOFError while sending emails through Django - django

Question

Settings
EMAIL_BACKEND = 'django.core.mail.backends.smtp.EmailBackend'
EMAIL_USE_TLS = True
EMAIL_HOST = 'smtp.gmail.com'
DEFAULT_FROM_EMAIL = EMAIL_HOST_USER = 'no_reply#domain.com'
SERVER_EMAIL = 'no_reply#domain.com'
DEFAULT_DO_NOT_REPLY = 'User <no_reply#domain.com>'
EMAIL_HOST_PASSWORD = 'xxxxxxxxx'
EMAIL_PORT = 587
DEFAULT_FROM_EMAIL = EMAIL_HOST_USER
Class
class EmailThread(threading.Thread):
def __init__(self, subject, context, recipient, template):
self.subject = subject
self.recipient = recipient
self.message = get_template(template).render(context)
threading.Thread.__init__(self)
def run(self):
msg = EmailMessage(
subject=self.subject,
from_email=settings.DEFAULT_DO_NOT_REPLY,
to=self.recipient,
body=self.message
)
msg.content_subtype = "html"
try:
msg.send(fail_silently=False)
log.info("E-mail triggered. Subject: '%s', to: %s" % (self.subject, self.recipient))
except Exception as e:
log.exception(e)
Usage
def notify_admin_blocked_account(user):
"""
Sends sends an email when the account is blocked
:return:
"""
email = EmailThread(
subject='{}, your account has been blocked'.format(user),
context={
'user': user,
'login_attempts': settings.MAX_STAFF_PWD_ATTEMPTS,
},
recipient=[user.email,],
template='mail/notify_admin_blocked_account.html'
)
email.start()
Error
[ERROR][2017-08-01 10:40:26,835][mail] EOF occurred in violation of protocol (_ssl.c:645)
Traceback (most recent call last):
File "./bin/mail.py", line 27, in run
msg.send(fail_silently=False)
File "/home/web/sites/envs/project/lib/python3.5/site-packages/django/core/mail/message.py", line 348, in send
return self.get_connection(fail_silently).send_messages([self])
File "/home/web/sites/envs/project/lib/python3.5/site-packages/django/core/mail/backends/smtp.py", line 104, in send_messages
new_conn_created = self.open()
File "/home/web/sites/envs/project/lib/python3.5/site-packages/django/core/mail/backends/smtp.py", line 69, in open
self.connection.starttls(keyfile=self.ssl_keyfile, certfile=self.ssl_certfile)
File "/usr/lib/python3.5/smtplib.py", line 766, in starttls
server_hostname=self._host)
File "/usr/lib/python3.5/ssl.py", line 377, in wrap_socket
_context=self)
File "/usr/lib/python3.5/ssl.py", line 752, in __init__
self.do_handshake()
File "/usr/lib/python3.5/ssl.py", line 988, in do_handshake
self._sslobj.do_handshake()
File "/usr/lib/python3.5/ssl.py", line 633, in do_handshake
self._sslobj.do_handshake()
ssl.SSLEOFError: EOF occurred in violation of protocol (_ssl.c:645)
I have some weird behavior when I try to send an e-mail (async) with Django. I really wanted to avoid third-party apps being installed to reduce code fragmentation - specially with some of them that seem to use crontab.
It is worth noticing that the error doesn't happen all the time. However, even though it doesn't happen, sometimes e-mails are not sent either. Only some of them manage to go through.
On my development environment it runs fine, and I can send the e-mails. However, on my production environment (EC2 instance) it simply doesn't work.
If I trigger an e-mail through the normal process, it is not sent. If I login to the server, open the manage.py shell, import a project and call the function that sends e-mail, sometimes I receive both triggered and manually-triggered e-mails or get an error (the one bellow).

Answer 1

My solution was to use Django-Mailer. It fragments the project, something I wanted to avoid, but its usage is pretty minimalist.