NB OAuth Test

<?php
require('Client.php');
require('IGrantType.php');
require('AuthorizationCode.php');

const CLIENT_ID	= 'e8fefc347be6be281bf217d254cbdd5c4ec21f9ea889bfeee3d87bd95222ad9f';
const CLIENT_SECRET	= '958abd92ca65034f6966c22a579abf93cba220b36831a04fc73e98ed11d0093a';
 
const REDIRECT_URI 			= "http://example.com/";
const AUTHORIZATION_ENDPOINT	= "https://arion.nationbuilder.com/oauth/authorize";
const TOKEN_ENDPOINT		= "https://arion.nationbuilder.com/oauth/token";
const REQUEST_ENDPOINT		= "https://arion.nationbuilder.com/api/v1";
 
$client = new OAuth2\Client(CLIENT_ID, CLIENT_SECRET);

if (!isset($_GET['code'])) {
	$auth_url = $client->getAuthenticationUrl(AUTHORIZATION_ENDPOINT, REDIRECT_URI);
	header('Location: ' . $auth_url);
	die('Redirect');
}
 
$params = array('code' => $_GET['code'], 'redirect_uri' => REDIRECT_URI); 
$response = $client->getAccessToken(TOKEN_ENDPOINT, 'authorization_code', $params);
 
if (isset($response['result']['error'])) {
	switch($response['result']['error']) {
		case 'invalid_grant':
			header('Location: ' . REDIRECT_URI); 
 			$error = "<b>ERROR</b>: Invalid Grant. This code is invalid, expired, or revoked.<br>";
			break;
		default:
			$error = "<b>Unknown error:</b> " . $response['result']['error'] . " - " . 
				$response['result']['error_description'] . "<br>";
			break;
	}
	die($error);
}
 
$token = $response['result']['access_token'];
$client->setAccessTokenType(1);
$client->setAccessToken($token);
?>