Appearance

Create A Custom Payment Gateway For Paymattic ​

Paymattic allows you to extend its functionality by creating a custom payment gateway add-on for regional or specific business needs. If you are a developer or have a team with coding experience, you can create your own custom payment gateway for Paymattic.

This article will guide you through building a complete payment gateway add-on that handles payments, manages subscriptions, and processes refunds.

Prerequisites ​

To build and integrate a custom payment gateway, you will need:

  • The Paymattic Pro Plugin is installed on your WordPress site.
  • Developer skills or a development team to create the custom code.

Steps to Build Your Payment Gateway ​

Your custom payment gateway add-on can be created in only six steps, making it ready to process real transactions.

Step 1: Set up your plugin structure ​

Before diving into the code, set up a clean and organized folder layout for your plugin. Here is the recommended folder structure:

your-gateway-for-paymattic/ (main plugin folder)
├── your-gateway-for-paymattic.php (main plugin file)
├── API/
│   ├── YourGatewayProcessor.php (payment logic)
│   └── API.php (gateway API calls)
└── Settings/
    ├── YourGatewayElement.php (form element)
    └── YourGatewaySettings.php (admin settings)

Step 2: Register your payment gateway ​

Open your main plugin file and add the required header to register your plugin with WordPress.

php

Plugin Name: YourGateway For Paymattic
Description: Custom payment gateway for Paymattic

This tells WordPress what your plugin is and helps Paymattic recognize it as a compatible payment gateway.

Step 3: Set up the processor init() method ​

The heart of your integration is the init() method within your processor file, where you connect your custom gateway to Paymattic's payment engine.

You must initialize your components and hook into Paymattic's payment system:

php
public function init() {
    // Initialize your components
    new YourGatewayElement();
    (new YourGatewaySettings())->init();
    (new YourGatewayAPI());
    
    // Hook into Paymattic's payment system
    add_filter('wppayform/choose_payment_method_for_submission', array($this, 'choosePaymentMethod'), 10, 4);
    add_action('wppayform/form_submission_make_payment_yourgateway', array($this, 'makeFormPayment'), 10, 7);
    add_action('wppayform_load_checkout_js_yourgateway', array($this, 'addCheckoutJs'), 10, 3);
}

Step 4: Create the payment element ​

Now you must make your gateway visible to users in the Paymattic form builder. To do this, extend Paymattic's BaseComponent and define your gateway details:

  • Set your gateway name so Paymattic can identify it.
  • Add your logo or brand icon to display in the payment options.
  • Define the label for the payment method that users will see on the form.
  • Push it to the list of available payment methods.

Step 5: Build your API and Settings classes ​

You will build two key classes that ensure your gateway is secure and configurable:

  • Settings Class: This class manages everything related to admin configuration, including API credentials and live/test mode toggles.
  • API Class: This class handles the actual communication with your payment provider, sending requests and receiving transaction responses securely.

Step 6: Configure your gateway fields ​

Your final task is to define the fields your gateway requires in the admin panel by using the globalFields() method inside your settings class.

Paymattic supports several field types, including:

  • payment_mode – Switch between Test and Live environments.
  • test_pub_key & live_pub_key – Public API keys.
  • test_secret_key & live_secret_key – Secret API keys.
  • text – For custom labels or button text.
  • checkbox – To enable or disable specific features.
  • html_attr – For documentation links or webhook URLs.

An example field setup looks like this:

php
public function globalFields() {
    return array(
        'payment_mode' => array(
            'type' => 'payment_mode',
            'options' => array('test' => 'Test', 'live' => 'Live')
        ),
        'live_api_key' => array(
            'type' => 'live_pub_key',
            'required' => true,
            'label' => 'Live API Key'
        ),
        'button_text' => array(
            'type' => 'text', 
            'value' => 'Pay with YourGateway'
        )
    );
}

Paymattic automatically generates a clean admin interface based on your field definitions.

Test and Deploy ​

You do not have to start from scratch. To save time, you can grab Paymattic's live Mollie add-on as your base structure and build from there.

Here is your quick launch checklist:

  1. Download the Mollie add-on from Paymattic's GitHub repository.
  2. Replace every instance of "mollie" with your gateway's name.
  3. Update the API calls to connect your chosen payment provider.
  4. Run a quick test and then deploy.

Reference Example Gateways ​

To help accelerate your development process, you can reference the full, working code of Paymattic's official payment gateway add-ons. These repositories serve as excellent starting templates for building your custom gateway:

This way, integrating a payment gateway takes under an hour, rather than weeks of complex documentation and debugging.

Need Help?

If you have any questions, concerns, or suggestions, please contact our support team. We're here to help!

Copyright © 2025 WPManageNinja