View file sdark.mobi/xsolla/server.php

<?php
require_once __DIR__ . '/../core/system.php';
define('API_KEY', 'qFTpQJbjuPwrIZ2R');
define('MERCHANT_ID', 10636);
define('PROJECT_ID', 17674);
define('PROJECT_KEY', 'Zo3P0HWUU5klMedK');
define('USER_ID', $user['id']);

require __DIR__ . '/../vendor/autoload.php';
error_reporting(E_ALL);
ini_set('display_errors', 1);

use Xsolla\SDK\Webhook\WebhookServer;
use Xsolla\SDK\Webhook\Message\Message;
use Xsolla\SDK\Exception\Webhook\XsollaWebhookException;

use Xsolla\SDK\API\XsollaClient;

$client = XsollaClient::factory(array(
    'merchant_id' => MERCHANT_ID,
    'api_key' => API_KEY
));
$paymentUIToken = $client->createCommonPaymentUIToken(PROJECT_ID, USER_ID,
$sandboxMode = true);

use Xsolla\SDK\Webhook\WebhookRequest;
use Xsolla\SDK\Webhook\WebhookResponse;

$httpHeaders = array();//TODO fetch HTTP request headers from $_SERVER or apache_request_headers()
$httpRequestBody = file_get_contents('php://input');
$clientIPv4 = $_SERVER['REMOTE_ADDR'];
$request = new WebhookRequest($httpHeaders, $httpRequestBody, $clientIPv4);
//or $request = WebhookRequest::fromGlobals();
$this->webhookAuthenticator->authenticate($request, $authenticateClientIp = true);// throws Xsolla\SDK\Exception\Webhook\XsollaWebhookException

$requestArray = $request->toArray();

$message = Message::fromArray($requestArray);
switch ($message->getNotificationType()) {
    case Message::USER_VALIDATION:
        /** @var Xsolla\SDK\Webhook\Message\UserValidationMessage $message */
        $userArray = $message->getUser();
        $userId = $message->getUserId();
        $messageArray = $message->toArray();
        // TODO если пользователь не найден, сгенерируйте Xsolla\SDK\Exception\Webhook\InvalidUserException
        break;
    case Message::PAYMENT:
        /** @var Xsolla\SDK\Webhook\Message\PaymentMessage $message */
        $userArray = $message->getUser();
        $paymentArray = $message->getTransaction();
        $paymentId = $message->getPaymentId();
        $externalPaymentId = $message->getExternalPaymentId();
        $paymentDetailsArray = $message->getPaymentDetails();
        $customParametersArray = $message->getCustomParameters();
        $isDryRun = $message->isDryRun();
        $messageArray = $message->toArray();
        // TODO если проведение платежа невозможно по каким-либо причинам, сгенерируйте Xsolla\SDK\Exception\Webhook\XsollaWebhookException
        break;
    case Message::REFUND:
        /** @var Xsolla\SDK\Webhook\Message\RefundMessage $message */
        $userArray = $message->getUser();
        $paymentArray = $message->getTransaction();
        $paymentId = $message->getPaymentId();
        $externalPaymentId = $message->getExternalPaymentId();
        $paymentDetailsArray = $message->getPaymentDetails();
        $customParametersArray = $message->getCustomParameters();
        $isDryRun = $message->isDryRun();
        $refundArray = $message->getRefundDetails();
        $messageArray = $message->toArray();
        // TODO если рефанд невозможен, сгенерируйте Xsolla\SDK\Exception\Webhook\XsollaWebhookException
        break;
    default:
        throw new XsollaWebhookException('Notification type not implemented');
}