Interkassa API for PHP

This library simplifies working with interkassa payment system V 2.0.

Basic usage

First you have to include and initialize the library:

<?php

include_once 'path/to/interkassa.php';
Interkassa::register();

This will register the library's autoload with PHP and allow you to use its classes without any further include statements.

Next, let's create a simple payment:

<?php

// The following parameters are provided by interkassa
$shop_id    = '...';
$secret_key = '...';

// Create a shop
$shop = Interkassa_Shop::factory(array(
    'id'         => $shop_id,
    'secret_key' => $secret_key
));

// Create a payment
$payment_id     = '...'; // Your payment id
$payment_amount = '...'; // The amount to charge your shop's user
$payment_desc   = '...'; // Payment description

$payment = $shop->createPayment(array(
    'id'          => $payment_id,
    'amount'      => $payment_amount,
    'description' => $payment_desc
));

We now have everything we need to render the payment form:

<?php

// ... create and configure the payment object

?>
<form action="<?= htmlentities($payment->getFormAction()); ?>" method="post">
    <?php foreach ($payment->getFormValues() as $field => $value): ?>
    <input type="hidden" name="<?= htmlentities($field); ?>" value="<?= htmlentities($value); ?>" />
    <?php endforeach; ?>
    <button type="submit">Submit</button>
</form>

Processing payment status requests

Interkassa can send payment status updates to a URL of your choosing. You can configure this URL via your account on interkassa or send the URL with other payment data:

<?php

$payment = $shop->createPayment(array(
    // ... usual payment data
    'status_url' => 'http://example.com/ik-status.php'
));

And inside the ik-status.php:

<?php

// ... initialize library as usual

$shop = Interkassa_Shop::factory(array(
    'id'         => $shop_id,
    'secret_key' => $secret_key
));

try {
    $status = $shop->receiveStatus($_POST); // POST is used by default
} catch (Interkassa_Exception $e) {
    // The signature was incorrect, send a 400 error to interkassa
    // They should resend payment status request until they receive a 200 status
    header('HTTP/1.0 400 Bad Request');
    exit;
}

$payment = $status->getPayment();

This transparently checks the signature of the payment.

The $status variable now contains an instance of Interkassa_Status class. The $payment variable holds an instance of Interkassa_Payment with all the initial data.

Note, that success and fail status updates are also supported, but do not have a signature, and are sent via the user's browser, so it is not recommended to rely on them.

Requirements

This library requires at least PHP 5.1.0 to work correctly. However, the most recent PHP version is always recommended.

License

This library is released under the Open Source MIT license, which gives you the possibility to use it and modify it in every circumstance.

For the full copyright and license information, please view the LICENSE file that was distributed with this source code.