postman pre-request script for refreshing auth token

postman_auth_req.js

const tokenUrl = 'https://signin.XXX.com/connect/token';

const clientId = '<client-id>';
const clientSecret = '<client-pw>';
const username = 'domain\\<your-uid-here>'; // insert
const pw = pm.globals.get("mypw");
const grant_type = 'password';
const scopes = 'openid email profile exprofile roles xxx-api';

const getTokenRequest = {
  method: 'POST',
  url: tokenUrl,
  body: {
      mode: 'formdata',
      formdata: [
          { key: 'grant_type', value: grant_type },
          { key: 'client_id', value: clientId },
          { key: 'client_secret', value: clientSecret },
          { key: 'scope', value: scopes},
          { key: 'username', value: username },
          { key: 'password', value: pw },   
      ]
  }
};

pm.sendRequest(getTokenRequest, (err, response) => {
  const jsonResponse = response.json();
  const newAccessToken = jsonResponse.access_token;

  pm.variables.set('access_token', newAccessToken);
});