farm-2.x-dev/modules/core/asset/asset.module

<?php

/**
 * @file
 * Hooks and customizations for the asset module.
 */

use Drupal\asset\Entity\AssetInterface;
use Drupal\asset\Event\AssetEvent;
use Drupal\Core\Render\Element;
use Drupal\Core\Routing\RouteMatchInterface;

/**
 * Implements hook_help().
 */
function asset_help($route_name, RouteMatchInterface $route_match) {
  $output = '';

  // Main module help for the asset module.
  if ($route_name == 'help.page.asset') {
    $output = '';
    $output .= '<h3>' . t('About') . '</h3>';
    $output .= '<p>' . t('Provides asset entity') . '</p>';
  }

  return $output;
}

/**
 * Implements hook_ENTITY_TYPE_presave().
 */
function asset_asset_presave(AssetInterface $asset) {

  // Dispatch an event on asset presave.
  // @todo Replace this with core event via https://www.drupal.org/node/2551893.
  $event = new AssetEvent($asset);
  $event_dispatcher = \Drupal::service('event_dispatcher');
  $event_dispatcher->dispatch($event, AssetEvent::PRESAVE);
}

/**
 * Implements hook_ENTITY_TYPE_insert().
 */
function asset_asset_insert(AssetInterface $asset) {

  // Dispatch an event on asset insert.
  // @todo Replace this with core event via https://www.drupal.org/node/2551893.
  $event = new AssetEvent($asset);
  $event_dispatcher = \Drupal::service('event_dispatcher');
  $event_dispatcher->dispatch($event, AssetEvent::INSERT);
}

/**
 * Implements hook_ENTITY_TYPE_update().
 */
function asset_asset_update(AssetInterface $asset) {

  // Dispatch an event on asset update.
  // @todo Replace this with core event via https://www.drupal.org/node/2551893.
  $event = new AssetEvent($asset);
  $event_dispatcher = \Drupal::service('event_dispatcher');
  $event_dispatcher->dispatch($event, AssetEvent::UPDATE);
}

/**
 * Implements hook_ENTITY_TYPE_delete().
 */
function asset_asset_delete(AssetInterface $asset) {

  // Dispatch an event on asset delete.
  // @todo Replace this with core event via https://www.drupal.org/node/2551893.
  $event = new AssetEvent($asset);
  $event_dispatcher = \Drupal::service('event_dispatcher');
  $event_dispatcher->dispatch($event, AssetEvent::DELETE);
}

/**
 * Implements hook_theme().
 */
function asset_theme() {
  return [
    'asset' => [
      'render element' => 'elements',
    ],
  ];
}

/**
 * Implements hook_theme_suggestions_HOOK().
 */
function asset_theme_suggestions_asset(array $variables) {
  $suggestions = [];
  $asset = $variables['elements']['#asset'];
  $sanitized_view_mode = strtr($variables['elements']['#view_mode'], '.', '_');

  $suggestions[] = 'asset__' . $sanitized_view_mode;
  $suggestions[] = 'asset__' . $asset->bundle();
  $suggestions[] = 'asset__' . $asset->bundle() . '__' . $sanitized_view_mode;
  $suggestions[] = 'asset__' . $asset->id();
  $suggestions[] = 'asset__' . $asset->id() . '__' . $sanitized_view_mode;

  return $suggestions;
}

/**
 * Prepares variables for asset templates.
 *
 * Default template: asset.html.twig.
 *
 * @param array $variables
 *   An associative array containing:
 *   - elements: An associative array containing the asset information and any
 *     fields attached to the asset. Properties used:
 *     - #asset: A \Drupal\asset\Entity\Asset object. The asset entity.
 *   - attributes: HTML attributes for the containing element.
 */
function template_preprocess_asset(array &$variables) {
  $variables['asset'] = $variables['elements']['#asset'];
  // Helpful $content variable for templates.
  foreach (Element::children($variables['elements']) as $key) {
    $variables['content'][$key] = $variables['elements'][$key];
  }
}