Python: “subject” not shown when sending email using smtplib module

Question

I am successfully able to send email using the smtplib module. But when the emial is sent, it does not include the subject in the email sent.

import smtplib
         


        

Answer 1

I think you have to include it in the message:

import smtplib

message = """From: From Person <from@fromdomain.com>
To: To Person <to@todomain.com>
MIME-Version: 1.0
Content-type: text/html
Subject: SMTP HTML e-mail test

This is an e-mail message to be sent in HTML format

<b>This is HTML message.</b>
<h1>This is headline.</h1>
"""

try:
   smtpObj = smtplib.SMTP('localhost')
   smtpObj.sendmail(sender, receivers, message)         
   print "Successfully sent email"
except SMTPException:
   print "Error: unable to send email"

code from: http://www.tutorialspoint.com/python/python_sending_email.htm

Answer 2

See the note at the bottom of smtplib's documentation:

In general, you will want to use the email package’s features to construct an email message, which you can then convert to a string and send via sendmail(); see email: Examples.

Here's the link to the examples section of email's documentation, which indeed shows the creation of a message with a subject line. https://docs.python.org/3/library/email.examples.html

It appears that smtplib doesn't support subject addition directly and expects the msg to already be formatted with a subject, etc. That's where the email module comes in.

Answer 3

This will work with Gmail and Python 3.6+ using the new "EmailMessage" object:

import smtplib
from email.message import EmailMessage

msg = EmailMessage()
msg.set_content('This is my message')

msg['Subject'] = 'Subject'
msg['From'] = "me@gmail.com"
msg['To'] = "you@gmail.com"

# Send the message via our own SMTP server.
server = smtplib.SMTP_SSL('smtp.gmail.com', 465)
server.login("me@gmail.com", "password")
server.send_message(msg)
server.quit()

Answer 4

You should probably modify your code to something like this:

from smtplib import SMTP as smtp
from email.mime.text import MIMEText as text

s = smtp(server)

s.login(<mail-user>, <mail-pass>)

m = text(message)

m['Subject'] = 'Hello!'
m['From'] = <from-address>
m['To'] = <to-address>

s.sendmail(<from-address>, <to-address>, m.as_string())

Obviously, the <> variables need to be actual string values, or valid variables, I just filled them in as place holders. This works for me when sending messages with subjects.

Answer 5

 import smtplib

 # creates SMTP session 

List item

 s = smtplib.SMTP('smtp.gmail.com', 587)

 # start TLS for security   
 s.starttls()

 # Authentication  
 s.login("login mail ID", "password")


 # message to be sent   
 SUBJECT = "Subject"   
 TEXT = "Message body"

 message = 'Subject: {}\n\n{}'.format(SUBJECT, TEXT)

 # sending the mail    
 s.sendmail("from", "to", message)

 # terminating the session    
 s.quit()

Answer 6

Attach it as a header:

message = 'Subject: {}\n\n{}'.format(SUBJECT, TEXT)

and then:

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

Also consider using standard Python module email - it will help you a lot while composing emails.