Issue #3498582 by bohart: Added Drupal 11 support and remove D9 after its EOL.

Closes #3498582

src/EventSubscriber/ReverseProxyHeaderClientIpRestore.php

@@ -19,21 +19,21 @@ class ReverseProxyHeaderClientIpRestore implements EventSubscriberInterface {
    *
    * @var \GuzzleHttp\ClientInterface
    */
-  protected $httpClient;
+  protected ClientInterface $httpClient;
 
   /**
    * The settings object.
    *
    * @var \Drupal\Core\Site\Settings
    */
-  protected $settings;
+  protected Settings $settings;
 
   /**
    * The logger.
    *
    * @var \Psr\Log\LoggerInterface
    */
-  protected $logger;
+  protected LoggerInterface $logger;
 
   /**
    * Constructs a ReverseProxyHeaderClientIpRestore.
@@ -45,7 +45,11 @@ class ReverseProxyHeaderClientIpRestore implements EventSubscriberInterface {
    * @param \Psr\Log\LoggerInterface $logger
    *   The reverse_proxy_header logger channel.
    */
-  public function __construct(ClientInterface $http_client, Settings $settings, LoggerInterface $logger) {
+  public function __construct(
+    ClientInterface $http_client,
+    Settings $settings,
+    LoggerInterface $logger,
+  ) {
     $this->httpClient = $http_client;
     $this->settings = $settings;
     $this->logger = $logger;
@@ -54,7 +58,7 @@ class ReverseProxyHeaderClientIpRestore implements EventSubscriberInterface {
   /**
    * {@inheritdoc}
    */
-  public static function getSubscribedEvents() {
+  public static function getSubscribedEvents(): array {
     // Priority is set to 350 (to run before RouterListener::onKernelRequest).
     // Which allows AuthenticationSubscriber methods to use the request IP.
     // @see \Symfony\Component\HttpKernel\EventListener\RouterListener::getSubscribedEvents
@@ -67,7 +71,7 @@ class ReverseProxyHeaderClientIpRestore implements EventSubscriberInterface {
   /**
    * Restores the origination client IP from the custom HTTP header.
    */
-  public function onRequest(RequestEvent $event) {
+  public function onRequest(RequestEvent $event): void {
 
     // Check the available settings.
     $reverse_proxy_header_name = $this->settings->get('reverse_proxy_header');
@@ -101,7 +105,10 @@ class ReverseProxyHeaderClientIpRestore implements EventSubscriberInterface {
    * @return bool
    *   Return TRUE if IP address is invalid.
    */
-  protected function isInvalidIpAddress($ip_address, $header_name) {
+  protected function isInvalidIpAddress(
+    string $ip_address,
+    string $header_name,
+  ): bool {
     $variables = [
       '@ip_address' => $ip_address,
       '@header_name' => $header_name,