Authentication Fails for User with 100+ Groups

[cpajr]

Found an issue where a user will fail to authenticate to its appropriate group when they have more than 100+ Azure AD groups assigned to its account.

Looking at your code, it looks like under routine __retrieve_usergroups it needs to iterate further when the @odata.nextLink value is available in the API return.

Not being totally familiar with the pull request process, I thought I would recommend the following code changes:

    def _retrieve_user_groups(self, user_id, access_token):
        LOGGER.debug(f"Attempting to retrieve groups for user with id {user_id}")
        return_values = []
        groups_url = f'https://graph.microsoft.com/v1.0/users/{user_id}/memberOf?$select=displayName,id'
        headers = {
            'Authorization': f'Bearer {access_token}',
            'Content-Type': 'application/json'
        }
        r = requests.get(groups_url, headers=headers)
        return_values.extend(r.json().get('value', []))
        nextLink = r.json().get('@odata.nextLink','')

        while (nextLink != ''):
            r = requests.get(nextLink,headers=headers)
            return_values.extend(r.json().get('value', []))
            nextLink = r.json().get('@odata.nextLink','')

        LOGGER.debug(f"Retrieved groups for {user_id} from MS Graph: {pformat(return_values)}")
        return return_values