README

The MONEI PHP SDK provides convenient access to the MONEI API from applications written in server-side PHP.

For collecting customer and payment information in the browser, use monei.js.

MONEI PHP SDK

Requirements

PHP 7.4 or later

Installation

Install the package using Composer:

composer require monei/monei-php-sdk

Then run composer install

Basic Usage

API Keys

The MONEI API uses API keys for authentication. You can obtain and manage your API keys in the MONEI Dashboard.

Types of API Keys

MONEI provides two types of API keys:

Test API Keys: Use these for development and testing. Transactions made with test API keys are not processed by real payment providers.
Live API Keys: Use these in production environments. Transactions made with live API keys are processed by real payment providers and will move actual money.

Each API key has a distinct prefix that indicates its environment:

Test API keys start with pk_test_ (e.g., pk_test_12345abcdef)
Live API keys start with pk_live_ (e.g., pk_live_12345abcdef)

By checking the prefix of an API key, you can quickly determine which environment you're working in. This is especially useful when you're managing multiple projects or environments.

API Key Security

Your API keys carry significant privileges, so be sure to keep them secure:

Keep your API keys confidential and never share them in publicly accessible areas such as GitHub, client-side code, or in your frontend application.
Use environment variables or a secure vault to store your API keys.
Restrict API key access to only the IP addresses that need them.
Regularly rotate your API keys, especially if you suspect they may have been compromised.

// Example of loading API key from environment variable (recommended)
$apiKey = getenv('MONEI_API_KEY');
$monei = new Monei\MoneiClient($apiKey);

Test Mode

To test your integration with MONEI, you need to switch to test mode using the toggle in the header of your MONEI Dashboard. When in test mode:

Generate your test API key in MONEI Dashboard → Settings → API Access
Configure your payment methods in MONEI Dashboard → Settings → Payment Methods

Important: Account ID and API key generated in test mode are different from those in live (production) mode and can only be used for testing purposes.

When using test mode, you can simulate various payment scenarios using test card numbers, Bizum phone numbers, and PayPal accounts provided in the MONEI Testing documentation.

Basic Client Usage

<?php
require_once(__DIR__ . '/vendor/autoload.php');

use Monei\Model\CreatePaymentRequest;
use Monei\Model\PaymentCustomer;

// Instantiate the client using the API key
$monei = new Monei\MoneiClient('YOUR_API_KEY');

try {
    // Using request classes for better type safety and IDE autocompletion
    $request = new CreatePaymentRequest([
        'amount' => 1250, // 12.50€
        'order_id' => '100100000001',
        'currency' => 'EUR',
        'description' => 'Items description',
        'customer' => new PaymentCustomer([
            'email' => 'john.doe@monei.com',
            'name' => 'John Doe'
        ])
    ]);
    
    $result = $monei->payments->create($request);
    print_r($result);
} catch (Exception $e) {
    echo 'Error while creating payment: ', $e->getMessage(), PHP_EOL;
}
?>

Payment Operations

Creating a Payment

Create a payment with customer information:

<?php
require_once(__DIR__ . '/vendor/autoload.php');

use Monei\Model\CreatePaymentRequest;
use Monei\Model\PaymentCustomer;
use Monei\Model\PaymentBillingDetails;
use Monei\Model\Address;

$monei = new Monei\MoneiClient('YOUR_API_KEY');

try {
    $request = new CreatePaymentRequest([
        'amount' => 1999, // Amount in cents (19.99)
        'order_id' => '12345',
        'currency' => 'EUR',
        'description' => 'Order #12345',
        'customer' => new PaymentCustomer([
            'email' => 'customer@example.com',
            'name' => 'John Doe',
            'phone' => '+34600000000'
        ]),
        'billing_details' => new PaymentBillingDetails([
            'address' => new Address([
                'line1' => '123 Main St',
                'city' => 'Barcelona',
                'country' => 'ES',
                'zip' => '08001'
            ])
        ]),
        'complete_url' => 'https://example.com/success',
        'fail_url' => 'https://example.com/failure',
        'callback_url' => 'https://example.com/webhook'
    ]);
    
    $result = $monei->payments->create($request);
    print_r($result);
} catch (Exception $e) {
    echo 'Error while creating payment: ', $e->getMessage(), PHP_EOL;
}
?>

Retrieving a Payment

Retrieve an existing payment by ID:

<?php
require_once(__DIR__ . '/vendor/autoload.php');

use Monei\ApiException;

$monei = new Monei\MoneiClient('YOUR_API_KEY');

try {
    $payment = $monei->payments->getPayment('pay_123456789');
    echo "Payment status: " . $payment->getStatus() . PHP_EOL;
} catch (ApiException $e) {
    echo 'Error retrieving payment: ', $e->getMessage(), PHP_EOL;
}
?>

Refunding a Payment

Process a full or partial refund:

<?php
require_once(__DIR__ . '/vendor/autoload.php');

use Monei\Model\RefundPaymentRequest;
use Monei\ApiException;

$monei = new Monei\MoneiClient('YOUR_API_KEY');

try {
    $refundRequest = new RefundPaymentRequest([
        'amount' => 500, // Partial refund of 5.00€
        'refund_reason' => 'Customer request'
    ]);
    
    $result = $monei->payments->refund('pay_123456789', $refundRequest);
    echo "Refund created with ID: " . $result->getId() . PHP_EOL;
} catch (ApiException $e) {
    echo 'Error refunding payment: ', $e->getMessage(), PHP_EOL;
}
?>

Integration Methods

Using the Prebuilt Payment Page

MONEI Hosted Payment Page is the simplest way to securely collect payments from your customers without building your own payment form.

Features

Designed to remove friction — Real-time card validation with built-in error messaging
Mobile-ready — Fully responsive design
International — Supports 13 languages
Multiple payment methods — Supports multiple payment methods including Cards, PayPal, Bizum, GooglePay, Apple Pay & Click to Pay
Customization and branding — Customizable logo, buttons and background color
3D Secure — Supports 3D Secure - SCA verification process
Fraud and compliance — Simplified PCI compliance and SCA-ready

You can customize the appearance in your MONEI Dashboard → Settings → Branding.

Integration Flow

Create a payment on your server

<?php
require_once(__DIR__ . '/vendor/autoload.php');

use Monei\Model\CreatePaymentRequest;
use Monei\Model\PaymentCustomer;

$monei = new Monei\MoneiClient('YOUR_API_KEY');

try {
    $request = new CreatePaymentRequest([
        'amount' => 110, // Amount in cents (1.10)
        'currency' => 'EUR',
        'order_id' => '14379133960355',
        'description' => 'Test Shop - #14379133960355',
        'customer' => new PaymentCustomer([
            'email' => 'customer@example.com'
        ]),
        'callback_url' => 'https://example.com/checkout/callback', // For asynchronous notifications
        'complete_url' => 'https://example.com/checkout/complete', // Redirect after payment
        'fail_url' => 'https://example.com/checkout/cancel' // Redirect if customer cancels
    ]);
    
    $result = $monei->payments->create($request);
    
    // Redirect the customer to the payment page
    if (isset($result->getNextAction()) && isset($result->getNextAction()->getRedirectUrl())) {
        header('Location: ' . $result->getNextAction()->getRedirectUrl());
        exit;
    }
} catch (Exception $e) {
    echo 'Error while creating payment: ', $e->getMessage(), PHP_EOL;
}
?>

Redirect the customer to the payment page

After creating a payment, you'll receive a response with a nextAction.redirectUrl. Redirect your customer to this URL to show them the MONEI Hosted payment page.

Customer completes the payment

The customer enters their payment information and completes any required verification steps (like 3D Secure).

Customer is redirected back to your website

If the customer completes the payment, they are redirected to the complete_url with a payment_id query parameter
If the customer cancels, they are redirected to the fail_url

Receive asynchronous notification

MONEI sends an HTTP POST request to your callback_url with the payment result. This ensures you receive the payment status even if the customer closes their browser during the redirect.

For more information about the hosted payment page, visit the MONEI Hosted Payment Page documentation.

Webhooks

Webhooks can be configured in the MONEI Dashboard → Settings → Webhooks.

Signature Verification

When receiving webhooks from MONEI, you should verify the signature to ensure the request is authentic:

<?php
require_once(__DIR__ . '/vendor/autoload.php');

use Monei\Model\PaymentStatus;
use Monei\ApiException;

$monei = new Monei\MoneiClient('YOUR_API_KEY');

// Parse raw body for signature verification
$rawBody = file_get_contents('php://input');

// Get the signature from the headers
$signature = $_SERVER['HTTP_MONEI_SIGNATURE'] ?? '';

try {
    // Verify the signature and get the decoded payload
    $payload = $monei->verifySignature($rawBody, $signature);
    
    // Process the webhook
    $eventType = $payload->type;
    
    // The data field contains the Payment object
    $payment = $payload->object;
    
    // Access Payment object properties directly
    $paymentId = $payment->id;
    $amount = $payment->amount;
    $currency = $payment->currency;
    $status = $payment->status;
    
    // Handle the event based on its type
    switch ($eventType) {
        case 'payment.succeeded':
            // Handle successful payment
            echo "Payment {$paymentId} succeeded: " . ($amount/100) . " {$currency}\n";
            break;
        case 'payment.failed':
            // Handle failed payment
            echo "Payment {$paymentId} failed with status: {$status}\n";
            break;
        // Handle other event types
    }
    
    http_response_code(200);
    echo json_encode(['received' => true]);
} catch (ApiException $e) {
    // Invalid signature
    http_response_code(401);
    echo json_encode(['error' => 'Invalid signature']);
}
?>

Handling Payment Callbacks

MONEI sends an HTTP POST request to your callback_url with the payment result. This ensures you receive the payment status even if the customer closes their browser during the redirect.

Example of handling the callback in a PHP script:

<?php
require_once(__DIR__ . '/vendor/autoload.php');

use Monei\Model\PaymentStatus;
use Monei\ApiException;

$monei = new Monei\MoneiClient('YOUR_API_KEY');

// Parse raw body for signature verification
$rawBody = file_get_contents('php://input');
$signature = $_SERVER['HTTP_MONEI_SIGNATURE'] ?? '';

try {
    // Verify the signature
    $payment = $monei->verifySignature($rawBody, $signature);
    
    // Update your order status based on the payment status
    if ($payment->status === PaymentStatus::SUCCEEDED) {
        // Payment successful - fulfill the order
        // Update your database, send confirmation email, etc.
    } else if ($payment->status === PaymentStatus::FAILED) {
        // Payment failed - notify the customer
        // Log the failure, update your database, etc.
    } else if ($payment->status === PaymentStatus::AUTHORIZED) {
        // Payment is authorized but not yet captured
        // You can capture it later
    } else if ($payment->status === PaymentStatus::CANCELED) {
        // Payment was canceled
    }
    
    // Acknowledge receipt of the webhook
    http_response_code(200);
    echo json_encode(['received' => true]);
} catch (ApiException $e) {
    // Invalid signature
    http_response_code(401);
    echo json_encode(['error' => 'Invalid signature']);
}
?>

Important Notes About Webhooks

Always verify the signature to ensure the webhook is coming from MONEI
Use the raw request body for signature verification
Return a 2xx status code to acknowledge receipt of the webhook
Process webhooks asynchronously for time-consuming operations
Implement idempotency to handle duplicate webhook events

MONEI Connect for Partners

If you're a partner or platform integrating with MONEI, you can act on behalf of your merchants by providing their Account ID. This is part of MONEI Connect, which allows platforms to manage multiple merchant accounts.

Important: When using Account ID functionality, you must:

Use a partner API key (not a regular merchant API key)
Provide a custom User-Agent to identify your platform

For more information about MONEI Connect and becoming a partner, visit the MONEI Connect documentation.

Account ID

Setting Account ID after initialization

<?php
require_once(__DIR__ . '/vendor/autoload.php');

use Monei\Model\CreatePaymentRequest;

// Initialize with your partner API key
$monei = new Monei\MoneiClient('YOUR_PARTNER_API_KEY');

// Set a custom User-Agent for your platform (required before setting Account ID)
$monei->setUserAgent('MONEI/YourPlatform/1.0.0');

// Set Account ID to act on behalf of a merchant
$monei->setAccountId('MERCHANT_ACCOUNT_ID');

// Make API calls on behalf of the merchant
try {
    $request = new CreatePaymentRequest([
        'amount' => 1250,
        'order_id' => '12345',
        'currency' => 'EUR'
    ]);
    
    $result = $monei->payments->create($request);
    print_r($result);
} catch (Exception $e) {
    echo 'Error while creating payment: ', $e->getMessage(), PHP_EOL;
}
?>

Custom User-Agent

When integrating as a MONEI Connect partner, your User-Agent should follow this format:

MONEI/<PARTNER_NAME>/<VERSION>

For example: MONEI/YourPlatform/1.0.0

This format helps MONEI identify your platform in API requests and is required when using the Partner API Key.

Examples with Proper User-Agent Format

<?php
// For a platform named "ShopManager" with version 2.1.0
$monei->setUserAgent('MONEI/ShopManager/2.1.0');

// For a platform named "PaymentHub" with version 3.0.1
$monei->setUserAgent('MONEI/PaymentHub/3.0.1');
?>

Note: When using Account ID, you must set a custom User-Agent before making any API calls. The User-Agent is validated when making API requests.

Important: To use this feature, you need to be registered as a MONEI partner and use your partner API key. Please contact connect@monei.com to register as a partner.

Managing Multiple Merchant Accounts

<?php
require_once(__DIR__ . '/vendor/autoload.php');

use Monei\Model\CreatePaymentRequest;

// Initialize with your partner API key
$monei = new Monei\MoneiClient('YOUR_PARTNER_API_KEY');

// Set a custom User-Agent for your platform
$monei->setUserAgent('MONEI/YourPlatform/1.0.0');

// Function to process payments for multiple merchants
function processPaymentsForMerchants($monei, $merchantAccounts) {
    $results = [];

    foreach ($merchantAccounts as $merchantId) {
        // Set the current merchant account
        $monei->setAccountId($merchantId);

        // Process payment for this merchant
        try {
            $request = new CreatePaymentRequest([
                'amount' => 1000,
                'order_id' => 'order-' . $merchantId . '-' . time(),
                'currency' => 'EUR'
            ]);
            
            $payment = $monei->payments->create($request);
            $results[$merchantId] = [
                'success' => true,
                'payment' => $payment
            ];
        } catch (Exception $e) {
            $results[$merchantId] = [
                'success' => false,
                'error' => $e->getMessage()
            ];
        }
    }

    return $results;
}

// Example usage
$merchantAccounts = ['merchant_1', 'merchant_2', 'merchant_3'];
$results = processPaymentsForMerchants($monei, $merchantAccounts);
print_r($results);
?>

Development

Building the SDK

The SDK is built using OpenAPI Generator. To build the SDK from the OpenAPI specification:

# Install dependencies
yarn install

# Generate SDK from remote OpenAPI spec
yarn build

# Generate SDK from local OpenAPI spec
yarn build:local

Tests

To run the unit tests:

composer install
./vendor/bin/phpunit

Code Style

This project follows the PSR-12 coding standard. We use PHP CS Fixer to enforce the coding standards.

To check the code style:

composer cs-check

To automatically fix code style issues:

composer cs-fix

Documentation

For the full documentation, check our Documentation portal.

For a comprehensive overview of all MONEI features and integration options, visit our main documentation portal. There you can explore guides for:

Using a prebuilt payment page with MONEI Hosted payment page
Building a custom checkout with MONEI UI components
Integrating with multiple e-commerce platforms
Connecting with business platforms and marketplaces

monei / monei-php-sdk

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