composer require aliyun/openapi-php-sdk

include_once '../vendor/autoload.php';

use Aliyun\Ecs\Request\V20140526 as Ecs;
use Aliyun\Core\DefaultAcsClient;
use Aliyun\Core\Profile\DefaultProfile;

$iClientProfile = DefaultProfile::getProfile("cn-hangzhou", "<your accessKey>", "<your accessSecret>");
$client = new DefaultAcsClient($iClientProfile);

$request = new Ecs\DescribeRegionsRequest();
$request->setMethod("GET");
$response = $client->getAcsResponse($request);
print_r($response);