Load message from an EML file and send it to an SMTP server.

load_n_send_eml.py

#!/usr/bin/env python3
import email
import email.utils
import smtplib


def load_eml(src_eml):
    """Load message from an EML file.

    Returns:
        _msg (email.message.Message): Message from an EML file.
    References:
        Parse an eml file
        https://docs.python.org/3/library/email.parser.html#email.message_from_bytes
        Prefer `message_from_bytes()` to `email.message_from_string()`
        https://stackoverflow.com/a/19508543/11042987
    """
    with open(src_eml, 'rb') as f:
        _msg = email.message_from_bytes(f.read())  # Prefer 'bytes' to 'string'
    # Update the dttm
    dttm = email.utils.format_datetime(email.utils.localtime())
    _msg.replace_header('date', dttm)
    return _msg


def send_message(msg_in):
    """Send a msg object to an SMTP server.

    Args:
        msg_in (email.message.Message):
    """
    _host = 'mail.example.com'
    _user = 'yourname@example.com'
    _pass = '<PASSWORD>'

    with smtplib.SMTP_SSL(_host, 465) as s:
        s.login(_user, _pass)
        s.send_message(msg_in)
    print('\033[93mEmail sent!\033[0m')


def main():
    """Load message from an EML file and send it to an SMTP server.
    """
    source_eml = 'source.eml'
    msg = load_eml(source_eml)
    send_message(msg)


if __name__ == '__main__':
    main()