Facing issue while using exchangelib to expand DL

Question

I have a webapp built using flask.

Now, I have a requirement which needs me to expand a distribution list. I came across exchangelib library and tried using it.

I'm able to configure without any issue. I'm using OAuth2. I also have an app registered on Azure.

The exchangelib configuration is :

from exchangelib import OAuth2Credentials,Version,Build,Configuration,Account,Credentials,IMPERSONATION,OAUTH2
from exchangelib.version import EXCHANGE_O365

username = '<primary_smtp_email_id>' 
tenant_id = app.config['APP_TENANT_ID']
client_id = app.config['APP_CLIENT_ID']
secret_value = app.config['APP_CLIENT_SECRET']
version=Version(build=EXCHANGE_O365)
credentials = OAuth2Credentials(client_id=client_id, client_secret=secret_value, tenant_id=tenant_id)

config = Configuration(service_endpoint = 'https://outlook.office365.com/EWS/Exchange.asmx',
                        credentials=credentials,
                        auth_type=OAUTH2 , 
                        version=version)
account = Account(username, credentials=credentials, autodiscover=False, config=config, access_type=IMPERSONATION)

And the code to expand a DL :

def print_expanded_dl(dl):
    for mailbox in account.protocol.expand_dl(dl):
        print(mailbox.email_address)

But, I'm getting an error when I call the print_expanded_dl function. The error that i am encountering is :

exchangelib.errors.ErrorInvalidExchangeImpersonationHeaderData: ExchangeImpersonation SOAP header must be present for this type of OAuth token.

Kindly help since I searched for similar cases and found that the access_type in configuration needs to be set to IMPERSONATION. I have already done it. Also, The app on Azure has the following permissions :

Also, If there is any other way to expand a distribution list using some other library, Feel free to suggest the same. Thank you.

Answer 1

You need to also set the identity attribute on your Credentials instance, as described in https://ecederstrand.github.io/exchangelib/#oauth-authentication