DRAFT: Closes #7063: Google font - Frontend part

inc/Engine/Media/Fonts/Context.php

@@ -0,0 +1,21 @@
+<?php
+
+namespace WP_Rocket\Engine\Media\Fonts;
+
+use WP_Rocket\Engine\Optimization\ContextInterface;
+
+class Context implements ContextInterface {
+	/**
+	 * Checks if the feature is allowed.
+	 *
+	 * @param array $data Optional. Data to check against.
+	 * @return bool
+	 */
+	public function is_allowed( array $data = [] ): bool {
+		if ( get_option( 'local_google_fonts' ) ) {
+			return false;
+		}
+
+		return wpm_apply_filters_typed( 'boolean', 'rocket_self_host_fonts', true );
+	}
+}

inc/Engine/Media/Fonts/Frontend/Controller.php

@@ -0,0 +1,55 @@
+<?php
+
+namespace WP_Rocket\Engine\Media\Fonts\Frontend;
+
+use WP_Rocket\Engine\Media\Fonts\Context;
+
+class Controller {
+	/**
+	 * Context instance.
+	 *
+	 * @var Context
+	 */
+	private $context;
+
+	/**
+	 * Constructor.
+	 *
+	 * @param Context $context Context instance.
+	 */
+	public function __construct( Context $context ) {
+		$this->context = $context;
+	}
+
+	/**
+	 * Rewrites the Google Fonts paths to local ones.
+	 *
+	 * @param string $html HTML content.
+	 * @return string
+	 */
+	public function rewrite_fonts( string $html ): string {
+		if ( ! $this->context->is_allowed() ) {
+			return $html;
+		}
+
+		// Use the URL hash value to get the CSS file paths.
+		$pattern = '/<link\s+[^>]*href=["\'](https:\/\/fonts\.googleapis\.com\/css2?[^"\']+)["\'][^>]*>/i';
+		$html    = preg_replace_callback( $pattern, [ $this, 'replace_font_url' ], $html );
+
+		return $html;
+	}
+
+	/**
+	 * Replaces the Google Fonts URL with the local one.
+	 *
+	 * @param array $matches Matches from the regex pattern.
+	 * @return string
+	 */
+	private function replace_font_url( array $matches ): string {
+		$google_fonts_url = $matches[1];
+		$hash             = md5( $google_fonts_url );
+		$local_url        = WP_ROCKET_CACHE_URL . "fonts/google-fonts/{$hash}.css";
+
+		return str_replace( $google_fonts_url, $local_url, $matches[0] ) . ' data-wpr-hosted-gf-parameters="' . esc_attr( wp_parse_url( $google_fonts_url, PHP_URL_QUERY ) ) . '"';
+	}
+}

inc/Engine/Media/Fonts/Frontend/Subscriber.php

@@ -0,0 +1,44 @@
+<?php
+
+namespace WP_Rocket\Engine\Media\Fonts\Frontend;
+
+use WP_Rocket\Event_Management\Subscriber_Interface;
+
+class Subscriber implements Subscriber_Interface {
+	/**
+	 * Frontend Controller instance.
+	 *
+	 * @var Controller
+	 */
+	private $frontend_controller;
+
+	/**
+	 * Constructor.
+	 *
+	 * @param Controller $frontend_controller Frontend Controller instance.
+	 */
+	public function __construct( Controller $frontend_controller ) {
+		$this->frontend_controller = $frontend_controller;
+	}
+
+	/**
+	 * Returns an array of events that this subscriber wants to listen to.
+	 *
+	 * @return array
+	 */
+	public static function get_subscribed_events(): array {
+		return [
+			'rocket_buffer' => [ 'rewrite_fonts', 18 ],
+		];
+	}
+
+	/**
+	 * Rewrites the Google Fonts paths to local ones.
+	 *
+	 * @param string $html HTML content.
+	 * @return string
+	 */
+	public function rewrite_fonts( string $html ): string {
+		return $this->frontend_controller->rewrite_fonts( $html );
+	}
+}

inc/Engine/Media/Fonts/ServiceProvider.php

@@ -0,0 +1,32 @@
+<?php
+
+namespace WP_Rocket\Engine\Media\Fonts;
+
+use WP_Rocket\Engine\Media\Fonts\Frontend\Subscriber as FrontendSubscriber;
+use WP_Rocket\Engine\Media\Fonts\Frontend\Controller as FrontendController;
+use WP_Rocket\Engine\Media\Fonts\Context;
+use WP_Rocket\Dependencies\League\Container\ServiceProvider\AbstractServiceProvider;
+
+class ServiceProvider extends AbstractServiceProvider {
+	/**
+	 * @var array
+	 */
+	protected $provides = [
+		'media_fonts_context',
+		'media_fonts_frontend_controller',
+		'media_fonts_frontend_subscriber',
+	];
+
+	/**
+	 * Registers the classes.
+	 *
+	 * @return void
+	 */
+	public function register() {
+		$this->getContainer()->add('media_fonts_context', Context::class);
+		$this->getContainer()->add('media_fonts_frontend_controller', FrontendController::class)
+			->withArgument('media_fonts_context');
+		$this->getContainer()->add('media_fonts_frontend_subscriber', FrontendSubscriber::class)
+			->withArgument('media_fonts_frontend_controller');
+	}
+}

inc/Plugin.php

@@ -53,6 +53,7 @@
 use WP_Rocket\Engine\Debug\ServiceProvider as DebugServiceProvider;
 use WP_Rocket\Engine\Common\PerformanceHints\ServiceProvider as PerformanceHintsServiceProvider;
 use WP_Rocket\Engine\Optimization\LazyRenderContent\ServiceProvider as LRCServiceProvider;
+use WP_Rocket\Engine\Media\Fonts\ServiceProvider as FontsServiceProvider;
 
 /**
  * Plugin Manager.
@@ -308,6 +309,7 @@ private function init_common_subscribers() {
 		$this->container->addServiceProvider( new SaasAdminServiceProvider() );
 		$this->container->addServiceProvider( new PerformanceHintsServiceProvider() );
 		$this->container->addServiceProvider( new LRCServiceProvider() );
+		$this->container->addServiceProvider( new FontsServiceProvider() );
 
 		$common_subscribers = [
 			'license_subscriber',
@@ -401,6 +403,7 @@ private function init_common_subscribers() {
 			'performance_hints_admin_subscriber',
 			'lrc_frontend_subscriber',
 			'taxonomy_subscriber',
+			'media_fonts_frontend_subscriber',
 		];
 
 		$host_type = HostResolver::get_host_service();