Sending mail from Python using SMTP

Question

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 SM         


        

Answer 1

What about this?

import smtplib

SERVER = "localhost"

FROM = "sender@example.com"
TO = ["user@example.com"] # must be a list

SUBJECT = "Hello!"

TEXT = "This message was sent with Python's smtplib."

# Prepare actual message

message = """\
From: %s
To: %s
Subject: %s

%s
""" % (FROM, ", ".join(TO), SUBJECT, TEXT)

# Send the mail

server = smtplib.SMTP(SERVER)
server.sendmail(FROM, TO, message)
server.quit()

Answer 2

You should make sure you format the date in the correct format - RFC2822.

Answer 3

Based on this example I made following function:

import smtplib
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText

def send_email(host, port, user, pwd, recipients, subject, body, html=None, from_=None):
    """ copied and adapted from
        https://stackoverflow.com/questions/10147455/how-to-send-an-email-with-gmail-as-provider-using-python#12424439
    returns None if all ok, but if problem then returns exception object
    """

    PORT_LIST = (25, 587, 465)

    FROM = from_ if from_ else user 
    TO = recipients if isinstance(recipients, (list, tuple)) else [recipients]
    SUBJECT = subject
    TEXT = body.encode("utf8") if isinstance(body, unicode) else body
    HTML = html.encode("utf8") if isinstance(html, unicode) else html

    if not html:
        # Prepare actual message
        message = """From: %s\nTo: %s\nSubject: %s\n\n%s
        """ % (FROM, ", ".join(TO), SUBJECT, TEXT)
    else:
                # https://stackoverflow.com/questions/882712/sending-html-email-using-python#882770
        msg = MIMEMultipart('alternative')
        msg['Subject'] = SUBJECT
        msg['From'] = FROM
        msg['To'] = ", ".join(TO)

        # Record the MIME types of both parts - text/plain and text/html.
        # utf-8 -> https://stackoverflow.com/questions/5910104/python-how-to-send-utf-8-e-mail#5910530
        part1 = MIMEText(TEXT, 'plain', "utf-8")
        part2 = MIMEText(HTML, 'html', "utf-8")

        # Attach parts into message container.
        # According to RFC 2046, the last part of a multipart message, in this case
        # the HTML message, is best and preferred.
        msg.attach(part1)
        msg.attach(part2)

        message = msg.as_string()


    try:
        if port not in PORT_LIST: 
            raise Exception("Port %s not one of %s" % (port, PORT_LIST))

        if port in (465,):
            server = smtplib.SMTP_SSL(host, port)
        else:
            server = smtplib.SMTP(host, port)

        # optional
        server.ehlo()

        if port in (587,): 
            server.starttls()

        server.login(user, pwd)
        server.sendmail(FROM, TO, message)
        server.close()
        # logger.info("SENT_EMAIL to %s: %s" % (recipients, subject))
    except Exception, ex:
        return ex

    return None

if you pass only body then plain text mail will be sent, but if you pass html argument along with body argument, html email will be sent (with fallback to text content for email clients that don't support html/mime types).

Example usage:

ex = send_email(
      host        = 'smtp.gmail.com'
   #, port        = 465 # OK
    , port        = 587  #OK
    , user        = "xxx@gmail.com"
    , pwd         = "xxx"
    , from_       = 'xxx@gmail.com'
    , recipients  = ['yyy@gmail.com']
    , subject     = "Test from python"
    , body        = "Test from python - body"
    )
if ex: 
    print("Mail sending failed: %s" % ex)
else:
    print("OK - mail sent"

Btw. If you want to use gmail as testing or production SMTP server, enable temp or permanent access to less secured apps:

• login to google mail/account
• go to: https://myaccount.google.com/lesssecureapps
• enable
• send email using this function or similar
• (recommended) go to: https://myaccount.google.com/lesssecureapps
• (recommended) disable

Answer 4

Make sure you don't have any firewalls blocking SMTP. The first time I tried to send an email, it was blocked both by Windows Firewall and McAfee - took forever to find them both.

Answer 5

See all those lenghty answers? Please allow me to self promote by doing it all in a couple of lines.

Import and Connect:

import yagmail
yag = yagmail.SMTP('john@doe.net', host = 'YOUR.MAIL.SERVER', port = 26)

Then it is just a one-liner:

yag.send('foo@bar.com', 'hello', 'Hello\nThis is a mail from your server\n\nBye\n')

It will actually close when it goes out of scope (or can be closed manually). Furthermore, it will allow you to register your username in your keyring such that you do not have to write out your password in your script (it really bothered me prior to writing yagmail!)

For the package/installation, tips and tricks please look at git or pip, available for both Python 2 and 3.

Answer 6

Here's a working example for Python 3.x

#!/usr/bin/env python3

from email.message import EmailMessage
from getpass import getpass
from smtplib import SMTP_SSL
from sys import exit

smtp_server = 'smtp.gmail.com'
username = 'your_email_address@gmail.com'
password = getpass('Enter Gmail password: ')

sender = 'your_email_address@gmail.com'
destination = 'recipient_email_address@gmail.com'
subject = 'Sent from Python 3.x'
content = 'Hello! This was sent to you via Python 3.x!'

# Create a text/plain message
msg = EmailMessage()
msg.set_content(content)

msg['Subject'] = subject
msg['From'] = sender
msg['To'] = destination

try:
    s = SMTP_SSL(smtp_server)
    s.login(username, password)
    try:
        s.send_message(msg)
    finally:
        s.quit()

except Exception as E:
    exit('Mail failed: {}'.format(str(E)))