Issue #2843999 by mglaman, bojanz, vasike: Implement IPN handler.

commerce_paypal.services.yml

@@ -0,0 +1,8 @@
+services:
+  commerce_paypal.logger:
+    class: Drupal\Core\Logger\LoggerChannel
+    factory: logger.factory:get
+    arguments: ['commerce_paypal']
+  commerce_paypal.ipn_handler:
+    class: Drupal\commerce_paypal\IPNHandler
+    arguments: ['@entity_type.manager', '@commerce_paypal.logger', '@http_client']

src/IPNHandler.php

@@ -0,0 +1,112 @@
+<?php
+
+namespace Drupal\commerce_paypal;
+
+use Drupal\Core\Entity\EntityTypeManagerInterface;
+use GuzzleHttp\ClientInterface;
+use Psr\Log\LoggerInterface;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpKernel\Exception\BadRequestHttpException;
+
+class IPNHandler implements IPNHandlerInterface {
+
+  /**
+   * The entity type manager.
+   *
+   * @var \Drupal\Core\Entity\EntityTypeManagerInterface
+   */
+  protected $entityTypeManager;
+
+  /**
+   * The logger.
+   *
+   * @var \Drupal\Core\Logger\LoggerChannelInterface
+   */
+  protected $logger;
+
+  /**
+   * The HTTP client.
+   *
+   * @var \GuzzleHttp\Client
+   */
+  protected $httpClient;
+
+  /**
+   * Constructs a new PaymentGatewayBase object.
+   *
+   * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entity_type_manager
+   *   The entity type manager.
+   * @param \Psr\Log\LoggerInterface $logger
+   *   The logger channel.
+   * @param \GuzzleHttp\ClientInterface $client
+   *   The client.
+   */
+  public function __construct(EntityTypeManagerInterface $entity_type_manager, LoggerInterface $logger, ClientInterface $client) {
+    $this->entityTypeManager = $entity_type_manager;
+    $this->logger = $logger;
+    $this->httpClient = $client;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function process(Request $request) {
+    // Get IPN request data.
+    $ipn_data = $this->getRequestDataArray($request->getContent());
+
+    // Exit now if the $_POST was empty.
+    if (empty($ipn_data)) {
+      $this->logger->warning('IPN URL accessed with no POST data submitted.');
+      throw new BadRequestHttpException('IPN URL accessed with no POST data submitted.');
+    }
+
+    // Make PayPal request for IPN validation.
+    $url = $this->getIpnValidationUrl($ipn_data);
+    $validate_ipn = 'cmd=_notify-validate&' . $request->getContent();
+    $request = $this->httpClient->post($url, [
+      'body' => $validate_ipn,
+    ])->getBody();
+    $paypal_response = $this->getRequestDataArray($request->getContents());
+
+    // If the IPN was invalid, log a message and exit.
+    if (isset($paypal_response['INVALID'])) {
+      $this->logger->alert('Invalid IPN received and ignored.');
+      throw new BadRequestHttpException('Invalid IPN received and ignored.');
+    }
+
+    return $ipn_data;
+  }
+
+  /**
+   * Get data array from a request content.
+   *
+   * @param string $request_content
+   *   The Request content.
+   *
+   * @return array
+   *   The request data array.
+   */
+  protected function getRequestDataArray($request_content) {
+    parse_str(html_entity_decode($request_content), $ipn_data);
+    return $ipn_data;
+  }
+
+  /**
+   * Gets the IPN URL to be used for validation for IPN data.
+   *
+   * @param array $ipn_data
+   *   The IPN request data from PayPal.
+   *
+   * @return string
+   *   The IPN validation URL.
+   */
+  protected function getIpnValidationUrl(array $ipn_data) {
+    if (!empty($ipn_data['test_ipn']) && $ipn_data['test_ipn'] == 1) {
+      return 'https://ipnpb.sandbox.paypal.com/cgi-bin/webscr';
+    }
+    else {
+      return 'https://ipnpb.paypal.com/cgi-bin/webscr';
+    }
+  }
+
+}

src/IPNHandlerInterface.php

@@ -0,0 +1,25 @@
+<?php
+
+namespace Drupal\commerce_paypal;
+
+use Symfony\Component\HttpFoundation\Request;
+
+/**
+ * Provides a handler for IPN requests from PayPal.
+ */
+interface IPNHandlerInterface {
+
+  /**
+   * Processes an incoming IPN request.
+   *
+   * @param \Symfony\Component\HttpFoundation\Request $request
+   *   The request.
+   *
+   * @return mixed
+   *   The request data array.
+   *
+   * @throws \Symfony\Component\HttpKernel\Exception\HttpException
+   */
+  public function process(Request $request);
+
+}