Calling an Azure Active Directory (AAD) secured Azure Function from Python

azure_aad_function.py

import json
import requests

with open('settings.json', 'r') as fp:
    settings = json.load(fp)

CLIENT_ID = settings['clientId']
CLIENT_SECRET = settings['clientSecret']
TENANT_ID = settings['tenantId']
APP_ID_URI = settings['appIdUri']

auth_body = {
    'grant_type': 'client_credentials',
    'client_id': CLIENT_ID,
    'client_secret': CLIENT_SECRET,
    'resource': APP_ID_URI
}

auth_uri = 'https://login.microsoftonline.com/{}/oauth2/token'.format(TENANT_ID)
auth_resp = requests.post(auth_uri, data=auth_body, headers={'Content-Type': 'application/x-www-form-urlencoded'})

if not auth_resp.ok:
    print('Failed to authenticate')
    print(auth_resp.text)
    exit(-1)

bearer_token = auth_resp.json()['access_token']
res = requests.get(
    'https://<functions app>.azurewebsites.net/<function>?code=<function key>',
    headers = {'Authorization': 'Bearer {}'.format(bearer_token)})

print(json.dumps(res.json(), indent=2))

settings.json

{
    "tenantId": "<Azure tenant ID>,
    "clientId": "<Application ID>",
    "clientSecret": "<Application Client Secret>",
    "appIdUri": "<Application ID URI>"
}