// Get AccessToken by IAM
<?php
use NextEvent\PHPSDK\Client;
use NextEvent\PHPSDK\Auth\IAMClient;

$credentials = ['user', 'password', 'scope']; // Your Credentials

$client = new Client($appUrl, $credentials, $widgetHash);

// stand alone
$iam_client = new IAMClient($credentials, $cache);
$token = $iam_client->getToken();

With the Token you can authorize requests to the NextEvent application by setting the Authorization Header.

$http->get(
  $url,
  ['headers' => [
    'Authorization' => $token->getAuthorizationHeader()
  ]]);