drupal/core/modules/sdc/sdc.module

<?php

/**
 * @file
 * Module implementation file.
 */

use Drupal\Core\Routing\RouteMatchInterface;
use Drupal\sdc\Plugin\Component;
use Drupal\sdc\ComponentPluginManager;

/**
 * @file
 * Module implementation file.
 */

// Set class aliases for the classes that will go into core.
// See the experimental modules policy https://www.drupal.org/core/experimental
// @todo: remove class aliases in #3354389
@class_alias('Drupal\sdc\Element\ComponentElement', 'Drupal\Core\Render\Element\ComponentElement');
@class_alias('Drupal\sdc\Exception\ComponentNotFoundException', 'Drupal\Core\Render\Component\Exception\ComponentNotFoundException');
@class_alias('Drupal\sdc\Exception\IncompatibleComponentSchema', 'Drupal\Core\Render\Component\Exception\IncompatibleComponentSchema');
@class_alias('Drupal\sdc\Exception\InvalidComponentDataException', 'Drupal\Core\Render\Component\Exception\InvalidComponentDataException');
@class_alias('Drupal\sdc\Exception\InvalidComponentException', 'Drupal\Core\Render\Component\Exception\InvalidComponentException');

/**
 * Implements hook_help().
 */
function sdc_help($route_name, RouteMatchInterface $route_match) {
  switch ($route_name) {
    case 'help.page.sdc':
      $output = '<h2>' . t('About') . '</h2>';
      $output .= '<p>' . t('Single Directory Components is a module that aims to simplify the front-end development workflow, and improve maintainability of core and contrib themes. For more information, see the <a href=":docs">online documentation for the Single Directory Components module</a>.', [
        ':docs' => 'https://www.drupal.org/docs/develop/theming-drupal/using-single-directory-components',
      ]) . '</p>';
      $output .= '<dl>';
      $output .= '<dt>' . t('General') . '</dt>';
      $output .= '<dd>' . t('Single Directory Components introduces the concept of UI components to Drupal core. A component is a combination of a Twig template, stylesheets, scripts, assets, and metadata, that live in the same directory. Components represent an encapsulated and re-usable UI element.') . '</dd>';
      $output .= '<dd>' . t('<a href=":sdc-docs">Single Directory Components</a> reduce the number of framework implementation details required to put templated HTML, CSS, and JS in a Drupal page. They also define explicit component APIs, and provide a methodology to replace a component provided upstream (in a parent theme or module).', [
        ':sdc-docs' => 'https://www.drupal.org/docs/develop/theming-drupal/using-single-directory-components',
      ]) . '</dd>';
      $output .= '</dl>';

      return $output;
  }
  return NULL;
}

/**
 * Implements hook_library_info_build().
 */
function sdc_library_info_build() {
  // Iterate over all the components to get the CSS and JS files.
  $plugin_manager = \Drupal::service('plugin.manager.sdc');
  assert($plugin_manager instanceof ComponentPluginManager);
  $components = $plugin_manager->getAllComponents();
  $libraries = array_reduce(
    $components,
    static function (array $libraries, Component $component) {
      $library = $component->library;
      if (empty($library)) {
        return $libraries;
      }
      $library_name = $component->getLibraryName();
      [, $library_id] = explode('/', $library_name);
      return array_merge($libraries, [$library_id => $library]);
    },
    []
  );
  $libraries['all'] = [
    'dependencies' => array_map(
      static fn(Component $component) => $component->getLibraryName(),
      $components
    ),
  ];
  return $libraries;
}