Omnipay Offline Dummy Gateway for testing
composer require descom/omnipay-offline-dummy
use Omnipay\Omnipay;
$gateway = Omnipay::create('OfflineDummy');
$request = $gateway->purchase([
'amount' => '12.00',
'description' => 'Test purchase',
'transactionId' => 1,
'url_notify' => 'http://example.com/payment/notify',
'url_return' => 'http://example.com/payment/return',
])->send();
$response->redirect();