Usage

Installations

To install the ICEPAY Checkout SDK, run the following command:

composer require icepay/checkout-sdk

The SDK requires implementations for PSR-7 (HTTP Message) and PSR-17 (HTTP Factory) interfaces. You can use any compatible libraries, such as Guzzle or Nyholm.

For example, to install the SDK along with Nyholm PSR-7 and Symfony HTTP Client, run:

composer require icepay/checkout-sdk nyholm/psr7 symfony/http-client

Basic Example

Here's a simple example of how to use the ICEPAY Checkout SDK:

require 'vendor/autoload.php';
use ICEPAY\Checkout\CheckoutClient;
use ICEPAY\Checkout\Models\Amount;
use ICEPAY\Checkout\Models\Request\Checkout;

$checkoutClient = (new CheckoutClient())->withAuthorization(merchantId: 'your_merchant_id', merchantSecret: 'your_merchant_secret');
$reference = '#' . time();
$checkoutRequest = new createCheckout(
    reference: $reference,
    description: 'Test Checkout',
    amount: new Amount(1234, Amount::CURRENCY_EUR),
);

$response = $this->checkoutClient->checkout($checkoutRequest);
print_r($response->links->checkout);

Using a custom HTTP Client

You can use your own PSR-7 and PSR-17 compatible HTTP client with the SDK. Here's an example client that wraps proprietary HTTP client logic:

<?php

use Nyholm\Psr7\Response;
use Psr\Http\Client\ClientInterface;
use Psr\Http\Message\RequestInterface;
use Psr\Http\Message\ResponseInterface;

class WpHttpWrapper implements ClientInterface
{
    public function sendRequest(RequestInterface $request): ResponseInterface
    {
        $args = [
            'method' => $request->getMethod(),
            'headers' => $request->getHeaders(),
		];

        if(!in_array($request->getMethod(), ['GET', 'HEAD'])){
            $args['body'] = $request->getBody();
        }

        $result = wp_remote_request($request->getUri(), $args);
        if(!is_wp_error($result))
        {
            throw new HttpException('HTTP request failed: ' . $result->get_error_message());
        }

        return new Response($result['response']['code'], $result['headers'], $result['body']);
    }
}

You can then use this custom HTTP client with the CheckoutClient like so:

$httpClient = new WpHttpWrapper();
$checkoutClient = (new CheckoutClient())
    ->withHttpClient($httpClient)
    ->withAuthorization(merchantId: 'your_merchant_id', merchantSecret: 'your_merchant_secret');

Handling Postback Requests

After a payment status changes, ICEPAY sends a postback request to the provided webhookUrl. You can handle this request and verify its authenticity using the following example:

use ICEPAY\Checkout\Models\Response\Checkout;
use Psr\Http\Message\MessageInterface;

function postbackHandler(MessageInterface $request): void {
    $providedSignature = $request->getHeader('ICEPAY-Signature');
    $body = $request->getBody()->getContents();
    $secretKey = 'your_merchant_secret_key'; // Replace with your actual secret key
    $calculatedSignature = base64_encode(hash_hmac('sha256', $body, $secretKey, true));
    if (!hash_equals($providedSignature[0], $calculatedSignature)) {
        // Invalid signature, reject the request
        http_response_code(400);
    }

    $payment = Checkout::fromResponse($body);
    // Process the updated payment data as needed
}

Development

Running PHPUnit

composer phpunit

Quick code example to get payment methods

To quickly test the code example to get payment methods, you can use the following script. Make sure to set your MERCHANT_ID and MERCHANT_SECRET in a .env file in the same directory.

use Dotenv\Dotenv;
use ICEPAY\Checkout\CheckoutClient;

require_once "vendor/autoload.php";

$dotenv = Dotenv::createImmutable(__DIR__);
$dotenv->safeLoad();
$checkoutClient = (new CheckoutClient())->withAuthorization(merchantId:  $_ENV['MERCHANT_ID'], merchantSecret: $_ENV['MERCHANT_SECRET']);

$paymentMethods = $checkoutClient->getPaymentMethods();
var_dump($paymentMethods[0]->id);