Payment

The extension supports custom payment methods, which can be added by creating an own extension that adds a new payment method and implement Event Listeners for the PSR-14 Events for the different payment actions. It is required, that the payment is processed by an external payment provider (e.g. Paypal payment page). Please refer to the General workflow image shown below.

It is also required, that each Event Listener uses a Fluid standalone view to render the output that will be shown in the desired payment action in sf_event_mgt

Note

Please note, that it is only possible to start the payment process after the registration has been confirmed by the user.

This section describes how to create your own payment solution for sf_event_mgt which makes use of the provided payment actions.

I will assume, that the new payment method is called mypaymentmethod and the extension key for the new payment method is sf_event_mgt_mypaymentmethod

General workflow

Depending on the selected payment method, the user is redirected to the payment providers payment page.

As a reference, please check this demo extension: https://github.com/derhansen/sf_event_mgt_payment_demo

1. Blank extension

First of all you need a blank TYPO3 extension with at least an ext_emconf.php and an ext_localconf.php file.

2. Registration of payment method

Add the following content to the file ext_localconf.php:

// Register payment provider
$GLOBALS['TYPO3_CONF_VARS']['EXTCONF']['sf_event_mgt']['paymentMethods']['mypaymentmethod'] = [
    'class' => 'DERHANSEN\\SfEventMgtMypaymentmethod\\Payment\\Mypaymentmethod',
    'extkey' => 'sf_event_mgt_mypaymentmethod'
];

3. Implement Event Listeners

Depending on the requirements of the payment method, you should implement an Event Listener for available PSR-14 Events. You should at least implement handling of redirect, success, failure and cancel actions.

The code below shows how to implement your payment method to the redirectAction PSR-14 Event of sf_event_mgt:

// Configuration/Services.yaml
services:
  Vendor\Extension\EventListener\YourListener:
    tags:
      - name: event.listener
        identifier: 'yourListener'
        event: DERHANSEN\SfEventMgt\Event\ProcessPaymentInitializeEvent

After you registered your event listener, you can add code for your Event Listener to initialize the payment:

<?php
namespace Vendor\Extension\EventListener;

use DERHANSEN\SfEventMgt\Event\ModifyDetailViewVariablesEvent;

class YourListener
{
    public function __invoke(ModifyDetailViewVariablesEvent $modifyDetailViewVariablesEvent): void {
       // Implement your code (e.g. add variables)
       $variables = $modifyDetailViewVariablesEvent->getVariables();
       $variables['newVariable'] = 'Just testing';
       $modifyDetailViewVariablesEvent->setVariables($variables);
    }
}

The setters in all events allow you to control the behavior of the payment process in the main extension.

4. Add payment class

Please refer to the class AbstractPayment in sf_event_mgt for possible settings. You payment class must extend AbstractPayment and you should override/set the local $enable properties in order to enable the actions in sf_event_mgt

Please also refer to the PaymentController in sf_event_mgt to see all available PSR-14 Events.

In this example I create the class \DERHANSEN\SfEventMgtMypaymentmethod\EventListener\MyPaymentRedirectResponse and as following:

class MyPaymentRedirectResponse
{
    #[AsEventListener('sf-event-mgt-mypaymentmethod/payment-redirect-response')]
    public function __invoke(ModifyPaymentRedirectResponseEvent $processPaymentInitializeEvent): void
    {
        if ($processPaymentInitializeEvent->getRegistration()->getPaymentmethod() !== 'mypaymentmethod') {
            return;
        }

        // @todo Initial payment provider and determine redirect URL
        $redirectUrl = 'https://paymentprovider.tld/foo/bar'

        $redirectResponse = new RedirectResponse($redirectUrl, 303);
        $processPaymentInitializeEvent->setResponse($redirectResponse);
    }
}

The event listener shows how to use the PSR-14 event ModifyPaymentRedirectResponseEvent to set a redirect response, which is handled by the extensions internal redirect process and redirects the user to the given redirect URL.

5. Implement methods

Step 4 already showed how to implement one action. Feel free to implement other required actions (at least success, failure and cancel to your need.

Each PSR-14 Event enables you to update the given registration. Just set the properties of the $registration object and set $updateRegistration to true.

It is also possible to remove a registrations, if payment failed or was cancelled. Please see the corresponding PSr-14 Events for possible options.

6. cHash in generated links

All links created in PaymentController will automatically have a cHash added by TYPO3. This should be ok for most scenarios, but sometimes the payment provider will append GET parameters to links (e.g. successUrl or failureUrl), which then leads to the situation, that the TYPO3 cHash check fails.

Since all Payment actions are uncached and the registration GET parameter is checked using a HMAC, the cHash can manually be removed from generated URLs by implementing the ProcessPaymentInitializeEvent PSR-14 event.

7. Security considerations

Make sure that rendered Fluid views do not contain sensitive data or possibilities for Cross Site Scripting (XSS) (values['html'] is rendered with f:format.raw).

Working with currencies

Since version 9.0 the extension allows to define the ISO 4217 currency code for the event price. The ISO 4217 currency code is saved to the event record and can be used when working with payment providers.

The extension provides the following helpers for currencies:

\DERHANSEN\SfEventMgt\Utility\CurrencyUtility class for currency data
<f:format.currencySymbol> ViewHelper to get the currency symbol for a currency