SumUp

SumUp has no hosted checkout thus their JS library is used as described below.

Using the provider

site/config/config.php

<?php

return [
   'bnomei.kart.provider' => 'sumup',
   // other options
];

API Credentials

.env

SUMUP_SECRET_KEY=ZZZ
SUMUP_SECRET_KEY=XXX
SUMUP_MERCHANT_CODE=MMMMMM

SumUp Checkout JS

site/templates/payment.php

<?php snippet('kart/sumup-checkout') ?>

<?php // or create a custom version based on the snippet ?>
<script>
  ...
</script>

Customers

The SumUp customer API is designed for managing subscriptions. While it is technically possible to link a customer to a shopping cart checkout, I believe that this linkage will not be visible in the SumUp dashboard. However, you can store customer data within the orders created by Kart in Kirby. To make that possible, you need to...

a) manually set the customer data during your checkout flow to the current session

<?php

kirby()->session()->set('bnomei.kart.sumup.customer', [
    'email' => $email,
    'name' => $name,
]);

Or b) forward the form fields within the checkout form of Kart

<p><strong><?= kart()->cart()->formattedSubtotal() ?> +tax</strong></p>
<form method="POST" action="<?= kart()->urls()->cart_checkout() ?>">
    <?php // TODO: You should add an invisible CAPTCHA here, like...?>
    <?php // snippet('kart/turnstile-form')?>
    <input type="hidden" name="redirect" value="<?= $page?->url() ?>">

    <!-- forwarding data to customer creation -->
    <input type="text" name="name">
    <input type="email" name="email">

    <button type="submit" onclick="this.disabled=true;this.form.submit();" <?= kart()->cart()->canCheckout() === false ? 'disabled' : '' ?>>Checkout</button>
</form>

Read more about the Kart checkout form here.

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