import json
import dataclasses
import requests

@dataclasses.dataclass
class Credentials:
  access_token: str
  refresh_token: str
  api_url: str

DATA_FILE = 'creds.json'
ENDPOINT = 'https://somtoday.nl/oauth2/token'
CLIENT_ID = 'D50E0C06-32D1-4B41-A137-A9A850C892C2'

def refresh():
  body = {
    "grant_type": 'refresh_token',
    "refresh_token": read('refresh_token'),
    "client_id": CLIENT_ID
  }

  data = requests.post(ENDPOINT, data=body).json()
  write(data) # Save credentials for refreshing the next time.

  api_url = data.get("somtoday_api_url", "https://api.somtoday.nl")
  refresh_token = data.get("refresh_token")
  access_token = data.get("access_token")

  return Credentials(access_token, refresh_token, api_url)

def read(key = None):
  with open(DATA_FILE, "r") as file:
    data = json.load(file)
    return data[key] if key else data

def write(data):
  with open(DATA_FILE, "w") as file:
    json.dump(data, file)

Python script for (re)authenticating with the Somtoday API.