[BUGFIX] Reset alreadyDisplayed news list between requests

Classes/Middleware/ResetAlreadyDisplayedMiddleware.php

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+<?php
+
+declare(strict_types=1);
+
+/*
+ * This file is part of the "news" Extension for TYPO3 CMS.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ */
+
+namespace GeorgRinger\News\Middleware;
+
+use Psr\Http\Message\ResponseInterface;
+use Psr\Http\Message\ServerRequestInterface;
+use Psr\Http\Server\MiddlewareInterface;
+use Psr\Http\Server\RequestHandlerInterface;
+
+/**
+ * $GLOBALS['EXT']['news']['alreadyDisplayed'] tracks news UIDs already shown
+ * on the current page (see ExcludeDisplayedNewsViewHelper and the
+ * excludeAlreadyDisplayedNews demand in NewsRepository). It is a plain PHP
+ * array, not request-scoped state.
+ *
+ * Under PHP-FPM (and any other SAPI that reuses one PHP process for several
+ * requests) this array is never cleared between requests. Every news item
+ * ever rendered via a list using excludeAlreadyDisplayedNews accumulates in
+ * it for the lifetime of the worker process: the resulting NOT IN (...)
+ * condition keeps growing, and on a site with a few thousand news records
+ * this eventually exhausts the configured memory_limit with a hard-to-debug
+ * "Allowed memory size exhausted" fatal error that has nothing to do with
+ * the page actually being rendered at that point.
+ *
+ * Resetting the array at the start of every request keeps the intended
+ * behaviour (no duplicate news within one page) while removing the
+ * cross-request growth.
+ */
+class ResetAlreadyDisplayedMiddleware implements MiddlewareInterface
+{
+    public function process(ServerRequestInterface $request, RequestHandlerInterface $handler): ResponseInterface
+    {
+        $GLOBALS['EXT']['news']['alreadyDisplayed'] = [];
+
+        return $handler->handle($request);
+    }
+}

Configuration/RequestMiddlewares.php

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+<?php
+
+use GeorgRinger\News\Middleware\ResetAlreadyDisplayedMiddleware;
+
+return [
+    'frontend' => [
+        'news/reset-already-displayed' => [
+            'target' => ResetAlreadyDisplayedMiddleware::class,
+            'description' => 'Reset $GLOBALS[\'EXT\'][\'news\'][\'alreadyDisplayed\'] per request to avoid unbounded growth under PHP-FPM worker reuse',
+            'after' => [
+                'typo3/cms-frontend/prepare-tsfe-rendering',
+            ],
+        ],
+    ],
+];