python - How do I send attachments using SMTP?

Question

I want to write a program that sends email using Python's smtplib. I searched through the document and the RFCs, but couldn't find anything related to attachments. Thus, I'm sure there's some higher-level concept I'm missing out on. Can someone clue me in on how attachments work in SMTP?

Answer 1

Here is an example of a message with a PDF attachment, a text "body" and sending via Gmail.

# Import smtplib for the actual sending function
import smtplib

# For guessing MIME type
import mimetypes

# Import the email modules we'll need
import email
import email.mime.application

# Create a text/plain message
msg = email.mime.Multipart.MIMEMultipart()
msg['Subject'] = 'Greetings'
msg['From'] = '[email protected]'
msg['To'] = '[email protected]'

# The main body is just another attachment
body = email.mime.Text.MIMEText("""Hello, how are you? I am fine.
This is a rather nice letter, don't you think?""")
msg.attach(body)

# PDF attachment
filename='simple-table.pdf'
fp=open(filename,'rb')
att = email.mime.application.MIMEApplication(fp.read(),_subtype="pdf")
fp.close()
att.add_header('Content-Disposition','attachment',filename=filename)
msg.attach(att)

# send via Gmail server
# NOTE: my ISP, Centurylink, seems to be automatically rewriting
# port 25 packets to be port 587 and it is trashing port 587 packets.
# So, I use the default port 25, but I authenticate. 
s = smtplib.SMTP('smtp.gmail.com')
s.starttls()
s.login('[email protected]','xyzpassword')
s.sendmail('[email protected]',['[email protected]'], msg.as_string())
s.quit()