Python: Emailing a pickled object without intermediate file

Question

I have a section of code that pickles an object and then attaches the file to an email. My code looks like this:

# create message
msg = MIMEMultipart('alternative')

# generate a pickled object
fh = open('my_obj.obj', 'wb')
pickle.dump(my_obj, fh)

# attach the object file
filename = 'my_obj.obj'
f = file(filename)
attachment = MIMEText(f.read())
attachment.add_header('Content-Disposition', 'attachment', filename=filename)           
msg.attach(attachment)

# add content to log message
msg['Subject'] = "This is the subject"
msg['From'] = fromaddr
body = """This is the body of the message"""
content = MIMEText(body, 'plain')
msg.attach(content)

# email the message
server = smtplib.SMTP('smtp.gmail.com:587')  
server.starttls()
server.login(username,password) 
server.sendmail(fromaddr, toaddr, msg.as_string())  
server.quit()

This works, but I end up with the my_obj.obj file still in the working directory. I could just delete the file after the code executes, but that seems ugly. Is there a way to execute this without creating an intermediate my_obj.obj file?

Answer 1

Instead of dump use dumps, it will return the serialized object as a string:

>>> str_obj = pickle.dumps([1,2,3])
>>> str_obj
'(lp0\nI1\naI2\naI3\na.'

Answer 2

What worked out for me is:

from email.mime.application import MIMEApplication

attachment = MIMEApplication(pkl.dumps(data))
attachment.add_header('Content-Disposition', 'attachment', filename="data.pkl")
msg.attach(attachment)