【第2回】ランダム画像取得サービスの実装とテスト方法

public://segregated_maps/<category>/<your-images>
# 実際のパスの例（環境により異なります）: web/sites/default/files/segregated_maps/africa/algeria.png

drush generate module
 Module name:
 ➤ Unmanaged Files
 Module machine name [unmanaged_files]:
 ➤ 
 Module description:
 ➤ Unmanaged files example
 Package [Custom]:
 ➤ 
 Dependencies (comma separated):
 ➤ 
 Would you like to create module file? [No]:
 ➤ 
 Would you like to create install file? [No]:
 ➤ 
 Would you like to create README.md file? [No]:
 ➤ 

services:
  unmanaged_files.handler:
    class: Drupal\unmanaged_files\Service\FileHandler
    arguments:
      - '@file_system'
      - '@stream_wrapper_manager'

<?php
namespace Drupal\unmanaged_files\Service;
use Drupal\Core\File\FileSystemInterface;
use Drupal\Core\StreamWrapper\StreamWrapperManagerInterface;
final class FileHandler {
  public function __construct(
    private FileSystemInterface $fs,
    private StreamWrapperManagerInterface $swm,
  ) {}
  /**
   * public://segregated_maps配下のランダムなファイルURIを1つ返します。
   * 見つからない場合はNULLを返します。
   *
   * @return string|null  例: 'public://segregated_maps/africa/algeria.png'
   */
  public function getRandomFile(): ?string {
    $baseUri = 'public://segregated_maps';
    $basePath = $this->fs->realpath($baseUri);
    if (!$basePath || !is_dir($basePath)) {
      return NULL;
    }
    $files = [];
    $iter = new \RecursiveIteratorIterator(
      new \RecursiveDirectoryIterator($basePath, \FilesystemIterator::SKIP_DOTS)
    );
    foreach ($iter as $f) {
      if ($f->isFile()) {
        $abs = $f->getPathname(); // ディスク上の絶対パス
        // 絶対パスをpublic:// URIに変換し直します。
        // $basePathは$baseUriにマップされます。
        $rel = ltrim(substr($abs, strlen($basePath)), DIRECTORY_SEPARATOR);
        $files[] = $baseUri . '/' . str_replace(DIRECTORY_SEPARATOR, '/', $rel);
      }
    }
    if (!$files) {
      return NULL;
    }
    return $files[array_rand($files)];
  }
}

unmanaged_files.test:
  path: '/unmanaged-files/test'
  defaults:
    _controller: '\Drupal\unmanaged_files\Controller\TestController::view'
    _title: 'Unmanaged files test'
  requirements:
    _permission: 'access content'

<?php
namespace Drupal\unmanaged_files\Controller;
use Drupal\Core\Controller\ControllerBase;
use Symfony\Component\DependencyInjection\ContainerInterface;
use Drupal\unmanaged_files\Service\FileHandler;
use Drupal\Core\File\FileUrlGeneratorInterface;
final class TestController extends ControllerBase {
  public function __construct(
    private FileHandler $handler,
    private FileUrlGeneratorInterface $urlGen,
  ) {}
  public static function create(ContainerInterface $c): self {
    return new self(
      $c->get('unmanaged_files.handler'),
      $c->get('file_url_generator'),
    );
  }
  public function view(): array {
    $uri = $this->handler->getRandomFile();
    if (!$uri) {
      return [
        '#markup' => '<p>public://segregated_maps配下にファイルが見つかりません。</p>',
      ];
    }
    $url = $this->urlGen->generateAbsoluteString($uri);
    return [
      '#type' => 'container',
      '#attributes' => ['class' => ['unmanaged-files-test']],
      'info' => ['#markup' => '<p>選択: <code class="inline">' . $uri . '</code></p>'],
      'img'  => [
        '#type' => 'html_tag',
        '#tag' => 'img',
        '#attributes' => ['src' => $url, 'alt' => 'ランダムな非管理ファイル'],
      ],
      '#cache' => [
        'max-age' => 1,
      ],
    ];
  }
}