Issue #3247543 by pivica, Berdir: Add fonts preloading support (4cf401b9) · Commits · project / bs_base

bs_base.theme

+57 −0

Original line number	Diff line number	Diff line
		@@ -22,6 +22,16 @@ function bs_base_theme_suggestions_page_alter(array &$suggestions, array $variab
		}
		}

		/**
		* Implements hook_page_attachments_alter().
		*/
		function bs_base_page_attachments_alter(&$attachments) {
		$active_theme = \Drupal::theme()->getActiveTheme();
		if (!empty($active_theme->getExtension()->info['preload-fonts']) && is_array($active_theme->getExtension()->info['preload-fonts'])) {
		bs_base_preload_fonts($active_theme->getExtension()->info['preload-fonts'], $attachments);
		}
		}

		/**
		* Implements hook__theme_suggestions_HOOK_alter() for form element.
		*/
		@@ -112,3 +122,50 @@ function bs_base_preprocess_maintenance_page(&$variables) {
		$variables['maintenance_image_path'] = file_url_transform_relative(file_create_url($maintenance_image['path']));
		}
		}

		/* Helpers */

		/**
		* Adds fonts preload links to head section.
		*
		* For more info visit next resources:
		* - @see https://www.freecodecamp.org/news/web-fonts-in-2018-f191a48367e8/#preload-fonts
		* - @see https://web.dev/preload-optional-fonts/
		*
		* @param array $fonts
		* An array of fonts paths to be preloaded.
		* @param array $attachments
		* An array of page attachments.
		*/
		function bs_base_preload_fonts(array $fonts, array &$attachments) {
		foreach ($fonts as $font) {
		// Support relative font path from root like '/libraries/.../....woff2' or
		// remote font paths.
		if (strpos($font, '/') === 0 \|\| strpos($font, 'http') === 0) {
		$uri = $font;
		}
		// Support twig expansion syntax like @custom_theme/fonts/font1.woff.
		elseif (preg_match('/^\@([^\/]+)(\/.+)$/', $font, $match)) {
		$uri = drupal_get_path('theme', $match[1]) . $match[2];
		}
		// Support relative font path from the current active theme.
		elseif (strpos($font, '/') !== 0) {
		$active_theme = \Drupal::theme()->getActiveTheme();
		$uri = $active_theme->getPath() . '/' . $font;
		}
		// Font path pattern is not recognized, skip it.
		else {
		continue;
		}

		$attachments['#attached']['html_head_link'][] = [[
		'rel' => 'preload',
		'as' => 'font',
		// @todo this two functions are depreciated in Drupal 9.3, fix it later.
		// @see https://www.drupal.org/node/2940031
		'href' => file_url_transform_relative(file_create_url($uri)),
		'type' => 'font/' . pathinfo($font, PATHINFO_EXTENSION),
		'crossorigin' => 'anonymous',
		], FALSE];
		}
		}