Sending mail from Python using SMTP

Eli Bendersky picture Eli Bendersky · Sep 15, 2008 · Viewed 220.8k times · Source

I'm using the following method to send mail from Python using SMTP. Is it the right method to use or are there gotchas I'm missing ?

from smtplib import SMTP
import datetime

debuglevel = 0

smtp = SMTP()
smtp.set_debuglevel(debuglevel)
smtp.connect('YOUR.MAIL.SERVER', 26)
smtp.login('USERNAME@DOMAIN', 'PASSWORD')

from_addr = "John Doe <[email protected]>"
to_addr = "[email protected]"

subj = "hello"
date = datetime.datetime.now().strftime( "%d/%m/%Y %H:%M" )

message_text = "Hello\nThis is a mail from your server\n\nBye\n"

msg = "From: %s\nTo: %s\nSubject: %s\nDate: %s\n\n%s" 
        % ( from_addr, to_addr, subj, date, message_text )

smtp.sendmail(from_addr, to_addr, msg)
smtp.quit()

Answer

Vincent Marchetti picture Vincent Marchetti · Sep 15, 2008

The script I use is quite similar; I post it here as an example of how to use the email.* modules to generate MIME messages; so this script can be easily modified to attach pictures, etc.

I rely on my ISP to add the date time header.

My ISP requires me to use a secure smtp connection to send mail, I rely on the smtplib module (downloadable at http://www1.cs.columbia.edu/~db2501/ssmtplib.py)

As in your script, the username and password, (given dummy values below), used to authenticate on the SMTP server, are in plain text in the source. This is a security weakness; but the best alternative depends on how careful you need (want?) to be about protecting these.

=======================================

#! /usr/local/bin/python


SMTPserver = 'smtp.att.yahoo.com'
sender =     'me@my_email_domain.net'
destination = ['recipient@her_email_domain.com']

USERNAME = "USER_NAME_FOR_INTERNET_SERVICE_PROVIDER"
PASSWORD = "PASSWORD_INTERNET_SERVICE_PROVIDER"

# typical values for text_subtype are plain, html, xml
text_subtype = 'plain'


content="""\
Test message
"""

subject="Sent from Python"

import sys
import os
import re

from smtplib import SMTP_SSL as SMTP       # this invokes the secure SMTP protocol (port 465, uses SSL)
# from smtplib import SMTP                  # use this for standard SMTP protocol   (port 25, no encryption)

# old version
# from email.MIMEText import MIMEText
from email.mime.text import MIMEText

try:
    msg = MIMEText(content, text_subtype)
    msg['Subject']=       subject
    msg['From']   = sender # some SMTP servers will do this automatically, not all

    conn = SMTP(SMTPserver)
    conn.set_debuglevel(False)
    conn.login(USERNAME, PASSWORD)
    try:
        conn.sendmail(sender, destination, msg.as_string())
    finally:
        conn.quit()

except:
    sys.exit( "mail failed; %s" % "CUSTOM_ERROR" ) # give an error message