Implement html compression

public/typo3conf/ext/ep_theme/Classes/Middleware/HtmlCompress.php

@@ -0,0 +1,54 @@
+<?php
+
+namespace EP\EpTheme\Middleware;
+
+use Psr\Http\Message\ResponseInterface;
+use Psr\Http\Message\ServerRequestInterface;
+use Psr\Http\Server\MiddlewareInterface;
+use Psr\Http\Server\RequestHandlerInterface;
+use TYPO3\CMS\Core\Configuration\ExtensionConfiguration;
+use TYPO3\CMS\Core\Http\StreamFactory;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use WyriHaximus\HtmlCompress\Factory;
+
+class HtmlCompress implements MiddlewareInterface
+{
+    public function process(ServerRequestInterface $request, RequestHandlerInterface $handler): ResponseInterface
+    {
+        $response = $handler->handle($request);
+
+        $compressionEnabled = GeneralUtility::makeInstance(ExtensionConfiguration::class)
+            ->get('ep_theme', 'compressHtml');
+
+        if (false === (bool)$compressionEnabled || $this->isTypeNumSet($request)) {
+            return $response;
+        }
+
+        $stream = $response->getBody();
+        $stream->rewind();
+        $content = $stream->getContents();
+        $newBody = (new StreamFactory())->createStream($this->compressHtml($content));
+        $response = $response->withBody($newBody);
+
+        return $response;
+    }
+
+    protected function compressHtml(string $html): string
+    {
+        $parser = Factory::construct();
+        $html = $parser->compress($html);
+        $html = $this->removeComments($html);
+
+        return $html;
+    }
+
+    protected function removeComments(string $html): string
+    {
+        return preg_replace('/<!--((?!TYPO3SEARCH)[\s\S])*?-->/', '', $html);
+    }
+
+    protected function isTypeNumSet(ServerRequestInterface $request): bool
+    {
+        return $request->getAttribute('routing')->getPageType() > 0;
+    }
+}

public/typo3conf/ext/ep_theme/Configuration/RequestMiddlewares.php

@@ -8,5 +8,14 @@ return [
                 'typo3/cms-frontend/site',
             ],
         ],
+        'ep/html-compress' => [
+            'target' => \EP\EpTheme\Middleware\HtmlCompress::class,
+            'before' => [
+                'typo3/cms-frontend/output-compression'
+            ],
+            'after' => [
+                'typo3/cms-adminpanel/renderer'
+            ],
+        ],
     ],
 ];

public/typo3conf/ext/ep_theme/ext_conf_template.txt

@@ -0,0 +1,3 @@
+# customsubcategory=100=General
+# cat=eptheme/100/100; type=boolean; label=Compress HTML
+compressHtml = 0