imap.Authenticate error in python

Question

Since using oauth2 is now necessary to login to an outlook email with imaplib, Ive gone through all the necessary steps, and got an access token. To authenticate I'm using the following line of code:

I originally thought the auth string was just the access token but apparently its a different string which has the token in it. How do I create the auth string? And will I even be able to login after using this line to authenticate?

imap.authenticate('XOAUTH2', lambda x: auth_string)

Answer 1

Hello @HR Admin , OAuth integration requires your application to use SASL XOAUTH2 format to encode and transmit the access token. SASL XOAUTH2 encodes the username, access token together in the following format:

base64("user=" + userName + "^Aauth=Bearer " + accessToken + "^A^A")

^A represents a Control + A (%x01).

For example, the SASL XOAUTH2 format to access ******@contoso.onmicrosoft.com with access token EwBAAl3BAAUFFpUAo7J3Ve0bjLBWZWCclRC3EoAA is:

base64("user=******@contoso.onmicrosoft.com^Aauth=Bearer EwBAAl3BAAUFFpUAo7J3Ve0bjLBWZWCclRC3EoAA^A^A")

In Python you would do something like this (auth_string is not base64 encoded in the samples I found which make me guess the authenticate method will encode it. If that's not the case then proceed to encode it with base64.b64encode(auth_string))

auth_string = 'user=%s\1auth=Bearer %s\1\1' % (username, access_token)
imap_conn.authenticate('XOAUTH2', lambda x: auth_string)

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