How to refresh access token for Microsoft Graph in Python

The connection to Microsoft Graph with Flask-OAuthlib described well in this tutorial.

One detail it’s missing - how to refresh the access token, because it expires in an hour. In Flask-OAuthlib there is no method for this but it can be done easily with a POST request.

import requests
from flask_oauthlib.client import OAuth

from .config import AZURE_CLIENT_ID, AZURE_CLIENT_SECRET

oauth = OAuth()

microsoft = oauth.remote_app(
    'azure',
    consumer_key=AZURE_CLIENT_ID,
    consumer_secret=AZURE_CLIENT_SECRET,
    request_token_params={'scope': ' '.join([
        'https://graph.microsoft.com/Group.Read.All',
        'https://graph.microsoft.com/User.Read.All',
        'offline_access'
    ])},
    base_url='https://graph.microsoft.com/v1.0/',
    request_token_url=None,
    access_token_method='POST',
    access_token_url='https://login.microsoftonline.com/common/oauth2/v2.0/token',
    authorize_url='https://login.microsoftonline.com/common/oauth2/v2.0/authorize')

def refresh_credentials(refresh_token):
    data = {
        'grant_type': 'refresh_token',
        'refresh_token': refresh_token,
        'client_id': microsoft.consumer_key,
        'client_secret': microsoft.consumer_secret}
    response = requests.post(microsoft.access_token_url, data=data)
    credentials = response.json()
    return credentials