FileHooks.php

<?php

namespace Drupal\file\Hook;

use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Datetime\Entity\DateFormat;
use Drupal\Core\StringTranslation\ByteSizeMarkup;
use Drupal\Core\Render\BubbleableMetadata;
use Drupal\file\Entity\File;
use Drupal\file\FileInterface;
use Drupal\Core\Entity\EntityStorageInterface;
use Drupal\Core\Url;
use Drupal\Core\Routing\RouteMatchInterface;
use Drupal\Core\Hook\Attribute\Hook;

/**
 * Hook implementations for file.
 */
class FileHooks {
    // cspell:ignore widthx
    
    /**
     * Implements hook_help().
     */
    public function help($route_name, RouteMatchInterface $route_match) {
        switch ($route_name) {
            case 'help.page.file':
                $output = '';
                $output .= '<h2>' . t('About') . '</h2>';
                $output .= '<p>' . t('The File module allows you to create fields that contain files. See the <a href=":field">Field module help</a> and the <a href=":field_ui">Field UI help</a> pages for general information on fields and how to create and manage them. For more information, see the <a href=":file_documentation">online documentation for the File module</a>.', [
                    ':field' => Url::fromRoute('help.page', [
                        'name' => 'field',
                    ])->toString(),
                    ':field_ui' => \Drupal::moduleHandler()->moduleExists('field_ui') ? Url::fromRoute('help.page', [
                        'name' => 'field_ui',
                    ])->toString() : '#',
                    ':file_documentation' => 'https://www.drupal.org/documentation/modules/file',
                ]) . '</p>';
                $output .= '<h2>' . t('Uses') . '</h2>';
                $output .= '<dl>';
                $output .= '<dt>' . t('Managing and displaying file fields') . '</dt>';
                $output .= '<dd>' . t('The <em>settings</em> and the <em>display</em> of the file field can be configured separately. See the <a href=":field_ui">Field UI help</a> for more information on how to manage fields and their display.', [
                    ':field_ui' => \Drupal::moduleHandler()->moduleExists('field_ui') ? Url::fromRoute('help.page', [
                        'name' => 'field_ui',
                    ])->toString() : '#',
                ]) . '</dd>';
                $output .= '<dt>' . t('Allowing file extensions') . '</dt>';
                $output .= '<dd>' . t('In the field settings, you can define the allowed file extensions (for example <em>pdf docx psd</em>) for the files that will be uploaded with the file field.') . '</dd>';
                $output .= '<dt>' . t('Storing files') . '</dt>';
                $output .= '<dd>' . t('Uploaded files can either be stored as <em>public</em> or <em>private</em>, depending on the <a href=":file-system">File system settings</a>. For more information, see the <a href=":system-help">System module help page</a>.', [
                    ':file-system' => Url::fromRoute('system.file_system_settings')->toString(),
                    ':system-help' => Url::fromRoute('help.page', [
                        'name' => 'system',
                    ])->toString(),
                ]) . '</dd>';
                $output .= '<dt>' . t('Restricting the maximum file size') . '</dt>';
                $output .= '<dd>' . t('The maximum file size that users can upload is limited by PHP settings of the server, but you can restrict by entering the desired value as the <em>Maximum upload size</em> setting. The maximum file size is automatically displayed to users in the help text of the file field.') . '</dd>';
                $output .= '<dt>' . t('Displaying files and descriptions') . '<dt>';
                $output .= '<dd>' . t('In the field settings, you can allow users to toggle whether individual files are displayed. In the display settings, you can then choose one of the following formats: <ul><li><em>Generic file</em> displays links to the files and adds icons that symbolize the file extensions. If <em>descriptions</em> are enabled and have been submitted, then the description is displayed instead of the file name.</li><li><em>URL to file</em> displays the full path to the file as plain text.</li><li><em>Table of files</em> lists links to the files and the file sizes in a table.</li><li><em>RSS enclosure</em> only displays the first file, and only in a RSS feed, formatted according to the RSS 2.0 syntax for enclosures.</li></ul> A file can still be linked to directly by its URI even if it is not displayed.') . '</dd>';
                $output .= '</dl>';
                return $output;
        }
    }
    
    /**
     * Implements hook_field_widget_info_alter().
     */
    public function fieldWidgetInfoAlter(array &$info) {
        // Allows using the 'uri' widget for the 'file_uri' field type, which uses it
        // as the default widget.
        // @see \Drupal\file\Plugin\Field\FieldType\FileUriItem
        $info['uri']['field_types'][] = 'file_uri';
    }
    
    /**
     * Implements hook_theme().
     */
    public function theme() : array {
        return [
            // From file.module.
'file_link' => [
                'variables' => [
                    'file' => NULL,
                    'description' => NULL,
                    'attributes' => [],
                ],
            ],
            'file_managed_file' => [
                'render element' => 'element',
            ],
            'file_audio' => [
                'variables' => [
                    'files' => [],
                    'attributes' => NULL,
                ],
            ],
            'file_video' => [
                'variables' => [
                    'files' => [],
                    'attributes' => NULL,
                ],
            ],
            'file_widget_multiple' => [
                'render element' => 'element',
            ],
            'file_upload_help' => [
                'variables' => [
                    'description' => NULL,
                    'upload_validators' => NULL,
                    'cardinality' => NULL,
                ],
            ],
        ];
    }
    
    /**
     * Implements hook_file_download().
     */
    public function fileDownload($uri) {
        // Get the file record based on the URI. If not in the database just return.
        
        /** @var \Drupal\file\FileRepositoryInterface $file_repository */
        $file_repository = \Drupal::service('file.repository');
        $file = $file_repository->loadByUri($uri);
        if (!$file) {
            return;
        }
        // Find out if a temporary file is still used in the system.
        if ($file->isTemporary()) {
            $usage = \Drupal::service('file.usage')->listUsage($file);
            if (empty($usage) && $file->getOwnerId() != \Drupal::currentUser()->id()) {
                // Deny access to temporary files without usage that are not owned by the
                // same user. This prevents the security issue that a private file that
                // was protected by field permissions becomes available after its usage
                // was removed and before it is actually deleted from the file system.
                // Modules that depend on this behavior should make the file permanent
                // instead.
                return -1;
            }
        }
        // Find out which (if any) fields of this type contain the file.
        $references = file_get_file_references($file, NULL, EntityStorageInterface::FIELD_LOAD_CURRENT, NULL);
        // Stop processing if there are no references in order to avoid returning
        // headers for files controlled by other modules. Make an exception for
        // temporary files where the host entity has not yet been saved (for example,
        // an image preview on a node/add form) in which case, allow download by the
        // file's owner.
        if (empty($references) && ($file->isPermanent() || $file->getOwnerId() != \Drupal::currentUser()->id())) {
            return;
        }
        if (!$file->access('download')) {
            return -1;
        }
        // Access is granted.
        $headers = file_get_content_headers($file);
        return $headers;
    }
    
    /**
     * Implements hook_cron().
     */
    public function cron() {
        $age = \Drupal::config('system.file')->get('temporary_maximum_age');
        $file_storage = \Drupal::entityTypeManager()->getStorage('file');
        
        /** @var \Drupal\Core\StreamWrapper\StreamWrapperManagerInterface $stream_wrapper_manager */
        $stream_wrapper_manager = \Drupal::service('stream_wrapper_manager');
        // Only delete temporary files if older than $age. Note that automatic cleanup
        // is disabled if $age set to 0.
        if ($age) {
            $fids = \Drupal::entityQuery('file')->accessCheck(FALSE)
                ->condition('status', FileInterface::STATUS_PERMANENT, '<>')
                ->condition('changed', \Drupal::time()->getRequestTime() - $age, '<')
                ->range(0, 100)
                ->execute();
            $files = $file_storage->loadMultiple($fids);
            foreach ($files as $file) {
                $references = \Drupal::service('file.usage')->listUsage($file);
                if (empty($references)) {
                    if (!file_exists($file->getFileUri())) {
                        if (!$stream_wrapper_manager->isValidUri($file->getFileUri())) {
                            \Drupal::logger('file system')->warning('Temporary file "%path" that was deleted during garbage collection did not exist on the filesystem. This could be caused by a missing stream wrapper.', [
                                '%path' => $file->getFileUri(),
                            ]);
                        }
                        else {
                            \Drupal::logger('file system')->warning('Temporary file "%path" that was deleted during garbage collection did not exist on the filesystem.', [
                                '%path' => $file->getFileUri(),
                            ]);
                        }
                    }
                    // Delete the file entity. If the file does not exist, this will
                    // generate a second notice in the watchdog.
                    $file->delete();
                }
                else {
                    \Drupal::logger('file system')->info('Did not delete temporary file "%path" during garbage collection because it is in use by the following modules: %modules.', [
                        '%path' => $file->getFileUri(),
                        '%modules' => implode(', ', array_keys($references)),
                    ]);
                }
            }
        }
    }
    
    /**
     * Implements hook_ENTITY_TYPE_predelete() for file entities.
     */
    public function filePredelete(File $file) {
        // @todo Remove references to a file that is in-use.
    }
    
    /**
     * Implements hook_tokens().
     */
    public function tokens($type, $tokens, array $data, array $options, BubbleableMetadata $bubbleable_metadata) {
        $token_service = \Drupal::token();
        $url_options = [
            'absolute' => TRUE,
        ];
        if (isset($options['langcode'])) {
            $url_options['language'] = \Drupal::languageManager()->getLanguage($options['langcode']);
            $langcode = $options['langcode'];
        }
        else {
            $langcode = NULL;
        }
        $replacements = [];
        if ($type == 'file' && !empty($data['file'])) {
            
            /** @var \Drupal\file\FileInterface $file */
            $file = $data['file'];
            foreach ($tokens as $name => $original) {
                switch ($name) {
                    // Basic keys and values.
                    case 'fid':
                        $replacements[$original] = $file->id();
                        break;
                    case 'uuid':
                        $replacements[$original] = $file->uuid();
                        break;
                    // Essential file data
                    case 'name':
                        $replacements[$original] = $file->getFilename();
                        break;
                    case 'path':
                        $replacements[$original] = $file->getFileUri();
                        break;
                    case 'mime':
                        $replacements[$original] = $file->getMimeType();
                        break;
                    case 'size':
                        $replacements[$original] = ByteSizeMarkup::create($file->getSize());
                        break;
                    case 'url':
                        // Ideally, this would use return a relative URL, but because tokens
                        // are also often used in emails, it's better to keep absolute file
                        // URLs. The 'url.site' cache context is associated to ensure the
                        // correct absolute URL is used in case of a multisite setup.
                        $replacements[$original] = $file->createFileUrl(FALSE);
                        $bubbleable_metadata->addCacheContexts([
                            'url.site',
                        ]);
                        break;
                    // These tokens are default variations on the chained tokens handled below.
                    case 'created':
                        $date_format = DateFormat::load('medium');
                        $bubbleable_metadata->addCacheableDependency($date_format);
                        $replacements[$original] = \Drupal::service('date.formatter')->format($file->getCreatedTime(), 'medium', '', NULL, $langcode);
                        break;
                    case 'changed':
                        $date_format = DateFormat::load('medium');
                        $bubbleable_metadata = $bubbleable_metadata->addCacheableDependency($date_format);
                        $replacements[$original] = \Drupal::service('date.formatter')->format($file->getChangedTime(), 'medium', '', NULL, $langcode);
                        break;
                    case 'owner':
                        $owner = $file->getOwner();
                        $bubbleable_metadata->addCacheableDependency($owner);
                        $name = $owner->label();
                        $replacements[$original] = $name;
                        break;
                }
            }
            if ($date_tokens = $token_service->findWithPrefix($tokens, 'created')) {
                $replacements += $token_service->generate('date', $date_tokens, [
                    'date' => $file->getCreatedTime(),
                ], $options, $bubbleable_metadata);
            }
            if ($date_tokens = $token_service->findWithPrefix($tokens, 'changed')) {
                $replacements += $token_service->generate('date', $date_tokens, [
                    'date' => $file->getChangedTime(),
                ], $options, $bubbleable_metadata);
            }
            if (($owner_tokens = $token_service->findWithPrefix($tokens, 'owner')) && $file->getOwner()) {
                $replacements += $token_service->generate('user', $owner_tokens, [
                    'user' => $file->getOwner(),
                ], $options, $bubbleable_metadata);
            }
        }
        return $replacements;
    }
    
    /**
     * Implements hook_token_info().
     */
    public function tokenInfo() {
        $types['file'] = [
            'name' => t("Files"),
            'description' => t("Tokens related to uploaded files."),
            'needs-data' => 'file',
        ];
        // File related tokens.
        $file['fid'] = [
            'name' => t("File ID"),
            'description' => t("The unique ID of the uploaded file."),
        ];
        $file['uuid'] = [
            'name' => t('UUID'),
            'description' => t('The UUID of the uploaded file.'),
        ];
        $file['name'] = [
            'name' => t("File name"),
            'description' => t("The name of the file on disk."),
        ];
        $file['path'] = [
            'name' => t("Path"),
            'description' => t("The location of the file relative to Drupal root."),
        ];
        $file['mime'] = [
            'name' => t("MIME type"),
            'description' => t("The MIME type of the file."),
        ];
        $file['size'] = [
            'name' => t("File size"),
            'description' => t("The size of the file."),
        ];
        $file['url'] = [
            'name' => t("URL"),
            'description' => t("The web-accessible URL for the file."),
        ];
        $file['created'] = [
            'name' => t("Created"),
            'description' => t("The date the file created."),
            'type' => 'date',
        ];
        $file['changed'] = [
            'name' => t("Changed"),
            'description' => t("The date the file was most recently changed."),
            'type' => 'date',
        ];
        $file['owner'] = [
            'name' => t("Owner"),
            'description' => t("The user who originally uploaded the file."),
            'type' => 'user',
        ];
        return [
            'types' => $types,
            'tokens' => [
                'file' => $file,
            ],
        ];
    }
    
    /**
     * Implements hook_form_FORM_ID_alter().
     *
     * Injects the file sanitization options into /admin/config/media/file-system.
     *
     * These settings are enforced during upload by the FileEventSubscriber that
     * listens to the FileUploadSanitizeNameEvent event.
     *
     * @see \Drupal\system\Form\FileSystemForm
     * @see \Drupal\Core\File\Event\FileUploadSanitizeNameEvent
     * @see \Drupal\file\EventSubscriber\FileEventSubscriber
     */
    public function formSystemFileSystemSettingsAlter(array &$form, FormStateInterface $form_state) : void {
        $config = \Drupal::config('file.settings');
        $form['filename_sanitization'] = [
            '#type' => 'details',
            '#title' => t('Sanitize filenames'),
            '#description' => t('These settings only apply to new files as they are uploaded. Changes here do not affect existing file names.'),
            '#open' => TRUE,
            '#tree' => TRUE,
        ];
        $form['filename_sanitization']['replacement_character'] = [
            '#type' => 'select',
            '#title' => t('Replacement character'),
            '#default_value' => $config->get('filename_sanitization.replacement_character'),
            '#options' => [
                '-' => t('Dash (-)'),
                '_' => t('Underscore (_)'),
            ],
            '#description' => t('Used when replacing whitespace, replacing non-alphanumeric characters or transliterating unknown characters.'),
        ];
        $form['filename_sanitization']['transliterate'] = [
            '#type' => 'checkbox',
            '#title' => t('Transliterate'),
            '#default_value' => $config->get('filename_sanitization.transliterate'),
            '#description' => t('Transliteration replaces any characters that are not alphanumeric, underscores, periods or hyphens with the replacement character. It ensures filenames only contain ASCII characters. It is recommended to keep transliteration enabled.'),
        ];
        $form['filename_sanitization']['replace_whitespace'] = [
            '#type' => 'checkbox',
            '#title' => t('Replace whitespace with the replacement character'),
            '#default_value' => $config->get('filename_sanitization.replace_whitespace'),
        ];
        $form['filename_sanitization']['replace_non_alphanumeric'] = [
            '#type' => 'checkbox',
            '#title' => t('Replace non-alphanumeric characters with the replacement character'),
            '#default_value' => $config->get('filename_sanitization.replace_non_alphanumeric'),
            '#description' => t('Alphanumeric characters, dots <span aria-hidden="true">(.)</span>, underscores <span aria-hidden="true">(_)</span> and dashes <span aria-hidden="true">(-)</span> are preserved.'),
        ];
        $form['filename_sanitization']['deduplicate_separators'] = [
            '#type' => 'checkbox',
            '#title' => t('Replace sequences of dots, underscores and/or dashes with the replacement character'),
            '#default_value' => $config->get('filename_sanitization.deduplicate_separators'),
        ];
        $form['filename_sanitization']['lowercase'] = [
            '#type' => 'checkbox',
            '#title' => t('Convert to lowercase'),
            '#default_value' => $config->get('filename_sanitization.lowercase'),
        ];
        $form['#submit'][] = 'file_system_settings_submit';
    }

}