Example Flask app showing how to manage a webapp-style authentication flow with python-o365(once/if my PR is accepted - in meantime, can be used with toyg/python-0365 on the webapp_flow branch)

o365_app.py

# when testing locally, set environment variable OAUTHLIB_INSECURE_TRANSPORT to 1
# so you can use http://localhost... in redirect
import os

from O365 import Connection
from flask import Flask, redirect, request, url_for, abort

# O365 secrets
APP_ID = os.environ.get('O365_APP_ID')
APP_PWD = os.environ.get('O365_APP_PWD')
TENANT_ID = os.environ.get('O365_TENANT_ID')
if not APP_ID or not APP_PWD:
    print("You must supply O365_APP_ID and O365_APP_PWD as environment variables")
    exit(1)
APP_CREDENTIALS = (APP_ID, APP_PWD)

# flask config
app = Flask(__name__)
app.secret_key = os.environ.get('FLASK_SEC_KEY')
app.config['SERVER_NAME'] = os.environ.get('FLASK_DOMAIN')  # e.g. localhost:8000

# transient cache of in-flow requests
_oauth_inflow_requests = {}

@app.route('/')
def start_0365_oauth():
    """
    Flow entry-point, that will redirect to MS login page
    and save the state.
    """
    scopes = ["https://graph.microsoft.com/Calendars.Read",
                  'offline_access']
    acceptance_url = url_for('complete_oauth', _external=True)
    conn = Connection(APP_CREDENTIALS,
                      tenant_id=TENANT_ID,
                      redirect_uri=acceptance_url,
                      scopes=scopes)
    # start the flow
    url, state, redirect_uri, scopes = conn.get_authorization_webflow(
        redirect_uri=acceptance_url,
        requested_scopes=scopes)
    # save the resulting details so that we can recreate the session later
    _oauth_inflow_requests[state] = (url, redirect_uri, scopes)
    # send user to MS
    return redirect(url)


@app.route('/oauth_accepted')
def complete_oauth():
    """ post-authentication/authorization callback."""
    try:
        # retrieve the details for this session
        state = request.args.get('state')
        url, redirect_url, scopes = _oauth_inflow_requests[state]
        # rebuild our connection
        conn = Connection(APP_CREDENTIALS, scopes=scopes, tenant_id=TENANT_ID)
        conn.recreate_session(state, redirect_uri=redirect_url, scopes=scopes)
        # fetch the actual token, finally
        result = conn.request_token(authorization_url=request.url,
                                    state=state,
                                    redirect_uri=redirect_url)
        # if true, we have an access token
        if result == True:
            # forget the session state
            _oauth_inflow_requests.pop(state)
            # now you have a working Connection, so you could do something like:
            # schedule = Schedule(con=conn, protocol=MSGraphProtocol())
            # return "<br>".join(schedule.list_calendars())
            # etc etc
        return str(result)
    except TypeError as e:
        app.logger.error("Called oauth acceptance url without state")
        abort(400)
    except KeyError as e:
        app.logger.error("Called oauth acceptance url with invalid state: {s}".format(s=e.args[0]))
        abort(400)


if __name__ == '__main__':
    app.run()