islandora/modules/islandora_audio/islandora_audio.module

<?php

/**
 * @file
 * Contains islandora_audio.module.
 *
 * This file is part of the Islandora Project.
 *
 * (c) Islandora Foundation
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

use Drupal\Core\Routing\RouteMatchInterface;

/**
 * Implements hook_help().
 */
function islandora_audio_help($route_name, RouteMatchInterface $route_match) {
  switch ($route_name) {
    // Main module help for the islandora module.
    case 'help.page.islandora_audio':
      $output = '';
      $output .= '<h3>' . t('About') . '</h3>';
      $output .= '<p>' . t('Islandora Audio adds audio derivative actions.') . '</p>';
      $output .= '<p>' . t('These can be used with microservices to automatically generate derivative audios.') . '</p>';
      return $output;

    default:
  }
}

/**
 * Implements hook_theme().
 */
function islandora_audio_theme() {
  return [
    'islandora_file_audio' => [
      'variables' => [
        'files' => [],
        'tracks' => NULL,
        'attributes' => NULL,
      ],
    ],
  ];
}