Send a email through googleapi gmail python using oauth2

Question

I'm trying to send a email as a user using OAuth 2. On Google's website they state:

This document defines the SASL XOAUTH2 mechanism for use with the IMAP AUTHENTICATE and SMTP AUTH commands. This mechanism allows the use of OAuth 2.0 Access Tokens to authenticate to a user's Gmail account.

Using the tests provided in their oauth2.py

smtp_conn = smtplib.SMTP('smtp.gmail.com', 587)
smtp_conn.set_debuglevel(True)
smtp_conn.ehlo('test')
smtp_conn.starttls()
smtp_conn.docmd('AUTH', 'XOAUTH2 ' + base64.b64encode(auth_string))

where you can test whether or not you can connect to their smtp servers using a provided access token it succeeds, but when I try to send a email using sendmail I get a failure.

If I add smtp_conn.sendmail('[email protected]', '[email protected]', 'msg') it says that I need to authenticate.

From the docs am I not authenticating when I send the AUTH command with the required auth string?

Thanks.

UPDATE *

So apparently if I re authenticate in the catch of a try catch statement it works.. Any ideas?

try:
    smtp_conn.sendmail('[email protected]', '[email protected]', 'cool')
except:
    smtp_conn.docmd('AUTH', 'XOAUTH2 ' + base64.b64encode(auth_string))
    smtp_conn.sendmail('[email protected]', '[email protected]', 'cool')

Answer 1

You need another ehlo call after starttls. So:

    smtp_conn = smtplib.SMTP('smtp.gmail.com', 587)
    smtp_conn.set_debuglevel(True)
    smtp_conn.ehlo()
    smtp_conn.starttls()
    smtp_conn.ehlo()
    smtp_conn.docmd('AUTH', 'XOAUTH2 ' + base64.b64encode(auth_string))