OEmbed.php

<?php

namespace Drupal\media\Plugin\media\Source;

use Drupal\Component\Render\PlainTextOutput;
use Drupal\Component\Utility\Crypt;
use Drupal\Core\Config\ConfigFactoryInterface;
use Drupal\Core\Entity\Display\EntityFormDisplayInterface;
use Drupal\Core\Entity\Display\EntityViewDisplayInterface;
use Drupal\Core\Entity\EntityFieldManagerInterface;
use Drupal\Core\Entity\EntityTypeManagerInterface;
use Drupal\Core\Field\FieldTypePluginManagerInterface;
use Drupal\Core\File\Exception\FileException;
use Drupal\Core\File\FileExists;
use Drupal\Core\File\FileSystemInterface;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Messenger\MessengerInterface;
use Drupal\Core\StringTranslation\TranslatableMarkup;
use Drupal\Core\Url;
use Drupal\Core\Utility\Token;
use Drupal\media\Attribute\OEmbedMediaSource;
use Drupal\media\IFrameUrlHelper;
use Drupal\media\MediaInterface;
use Drupal\media\MediaSourceBase;
use Drupal\media\MediaTypeInterface;
use Drupal\media\OEmbed\Resource;
use Drupal\media\OEmbed\ResourceException;
use Drupal\media\OEmbed\ResourceFetcherInterface;
use Drupal\media\OEmbed\UrlResolverInterface;
use GuzzleHttp\ClientInterface;
use Psr\Http\Client\ClientExceptionInterface;
use Psr\Http\Message\ResponseInterface;
use Psr\Log\LoggerInterface;
use Symfony\Component\DependencyInjection\ContainerInterface;
use Symfony\Component\Mime\MimeTypes;

/**
 * Provides a media source plugin for oEmbed resources.
 *
 * For security reasons, the oEmbed source (and, therefore, anything that
 * extends it) obeys a hard-coded list of allowed third-party oEmbed providers
 * set in its plugin definition's providers array. This array is a set of
 * provider names, exactly as they appear in the canonical oEmbed provider
 * database at https://oembed.com/providers.json.
 *
 * You can implement support for additional providers by defining a new plugin
 * that uses this class. This can be done in hook_media_source_info_alter().
 * For example:
 * @code
 * <?php
 *
 * function example_media_source_info_alter(array &$sources) {
 *   $sources['artwork'] = [
 *     'id' => 'artwork',
 *     'label' => $this->t('Artwork'),
 *     'description' => $this->t('Use artwork from Flickr and DeviantArt.'),
 *     'allowed_field_types' => ['string'],
 *     'default_thumbnail_filename' => 'no-thumbnail.png',
 *     'providers' => ['Deviantart.com', 'Flickr'],
 *     'class' => 'Drupal\media\Plugin\media\Source\OEmbed',
 *   ];
 * }
 * @endcode
 * The "Deviantart.com" and "Flickr" provider names are specified in
 * https://oembed.com/providers.json. The
 * \Drupal\media\Plugin\media\Source\OEmbed class already knows how to handle
 * standard interactions with third-party oEmbed APIs, so there is no need to
 * define a new class which extends it. With the code above, you will able to
 * create media types which use the "Artwork" source plugin, and use those media
 * types to link to assets on Deviantart and Flickr.
 */
class OEmbed extends MediaSourceBase implements OEmbedInterface {
    
    /**
     * The logger channel for media.
     *
     * @var \Psr\Log\LoggerInterface
     */
    protected $logger;
    
    /**
     * The messenger service.
     *
     * @var \Drupal\Core\Messenger\MessengerInterface
     */
    protected $messenger;
    
    /**
     * The HTTP client.
     *
     * @var \GuzzleHttp\Client
     */
    protected $httpClient;
    
    /**
     * The oEmbed resource fetcher service.
     *
     * @var \Drupal\media\OEmbed\ResourceFetcherInterface
     */
    protected $resourceFetcher;
    
    /**
     * The OEmbed manager service.
     *
     * @var \Drupal\media\OEmbed\UrlResolverInterface
     */
    protected $urlResolver;
    
    /**
     * The iFrame URL helper service.
     *
     * @var \Drupal\media\IFrameUrlHelper
     */
    protected $iFrameUrlHelper;
    
    /**
     * The file system.
     *
     * @var \Drupal\Core\File\FileSystemInterface
     */
    protected $fileSystem;
    
    /**
     * The token replacement service.
     *
     * @var \Drupal\Core\Utility\Token
     */
    protected $token;
    
    /**
     * Constructs a new OEmbed instance.
     *
     * @param array $configuration
     *   A configuration array containing information about the plugin instance.
     * @param string $plugin_id
     *   The plugin_id for the plugin instance.
     * @param mixed $plugin_definition
     *   The plugin implementation definition.
     * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entity_type_manager
     *   The entity type manager service.
     * @param \Drupal\Core\Entity\EntityFieldManagerInterface $entity_field_manager
     *   The entity field manager service.
     * @param \Drupal\Core\Config\ConfigFactoryInterface $config_factory
     *   The config factory service.
     * @param \Drupal\Core\Field\FieldTypePluginManagerInterface $field_type_manager
     *   The field type plugin manager service.
     * @param \Psr\Log\LoggerInterface $logger
     *   The logger channel for media.
     * @param \Drupal\Core\Messenger\MessengerInterface $messenger
     *   The messenger service.
     * @param \GuzzleHttp\ClientInterface $http_client
     *   The HTTP client.
     * @param \Drupal\media\OEmbed\ResourceFetcherInterface $resource_fetcher
     *   The oEmbed resource fetcher service.
     * @param \Drupal\media\OEmbed\UrlResolverInterface $url_resolver
     *   The oEmbed URL resolver service.
     * @param \Drupal\media\IFrameUrlHelper $iframe_url_helper
     *   The iFrame URL helper service.
     * @param \Drupal\Core\File\FileSystemInterface $file_system
     *   The file system.
     * @param \Drupal\Core\Utility\Token $token
     *   The token replacement service.
     */
    public function __construct(array $configuration, $plugin_id, $plugin_definition, EntityTypeManagerInterface $entity_type_manager, EntityFieldManagerInterface $entity_field_manager, ConfigFactoryInterface $config_factory, FieldTypePluginManagerInterface $field_type_manager, LoggerInterface $logger, MessengerInterface $messenger, ClientInterface $http_client, ResourceFetcherInterface $resource_fetcher, UrlResolverInterface $url_resolver, IFrameUrlHelper $iframe_url_helper, FileSystemInterface $file_system, Token $token) {
        parent::__construct($configuration, $plugin_id, $plugin_definition, $entity_type_manager, $entity_field_manager, $field_type_manager, $config_factory);
        $this->logger = $logger;
        $this->messenger = $messenger;
        $this->httpClient = $http_client;
        $this->resourceFetcher = $resource_fetcher;
        $this->urlResolver = $url_resolver;
        $this->iFrameUrlHelper = $iframe_url_helper;
        $this->fileSystem = $file_system;
        $this->token = $token;
    }
    
    /**
     * {@inheritdoc}
     */
    public static function create(ContainerInterface $container, array $configuration, $plugin_id, $plugin_definition) {
        return new static($configuration, $plugin_id, $plugin_definition, $container->get('entity_type.manager'), $container->get('entity_field.manager'), $container->get('config.factory'), $container->get('plugin.manager.field.field_type'), $container->get('logger.factory')
            ->get('media'), $container->get('messenger'), $container->get('http_client'), $container->get('media.oembed.resource_fetcher'), $container->get('media.oembed.url_resolver'), $container->get('media.oembed.iframe_url_helper'), $container->get('file_system'), $container->get('token'));
    }
    
    /**
     * {@inheritdoc}
     */
    public function getMetadataAttributes() {
        return [
            'type' => $this->t('Resource type'),
            'title' => $this->t('Resource title'),
            'author_name' => $this->t('Author/owner name'),
            'author_url' => $this->t('Author/owner URL'),
            'provider_name' => $this->t('Provider name'),
            'provider_url' => $this->t('Provider URL'),
            'cache_age' => $this->t('Suggested cache lifetime'),
            'default_name' => $this->t('Media item default name'),
            'thumbnail_uri' => $this->t('Thumbnail local URI'),
            'thumbnail_width' => $this->t('Thumbnail width'),
            'thumbnail_height' => $this->t('Thumbnail height'),
            'url' => $this->t('Resource source URL'),
            'width' => $this->t('Resource width'),
            'height' => $this->t('Resource height'),
            'html' => $this->t('Resource HTML representation'),
        ];
    }
    
    /**
     * {@inheritdoc}
     */
    public function getMetadata(MediaInterface $media, $name) {
        $media_url = $this->getSourceFieldValue($media);
        // The URL may be NULL if the source field is empty, in which case just
        // return NULL.
        if (empty($media_url)) {
            return NULL;
        }
        try {
            $resource_url = $this->urlResolver
                ->getResourceUrl($media_url);
            $resource = $this->resourceFetcher
                ->fetchResource($resource_url);
        } catch (ResourceException $e) {
            $this->messenger
                ->addError($e->getMessage());
            return NULL;
        }
        switch ($name) {
            case 'default_name':
                if ($title = $this->getMetadata($media, 'title')) {
                    return $title;
                }
                elseif ($url = $this->getMetadata($media, 'url')) {
                    return $url;
                }
                return parent::getMetadata($media, 'default_name');
            case 'thumbnail_uri':
                return $this->getLocalThumbnailUri($resource, $media) ?: parent::getMetadata($media, 'thumbnail_uri');
            case 'type':
                return $resource->getType();
            case 'title':
                return $resource->getTitle();
            case 'author_name':
                return $resource->getAuthorName();
            case 'author_url':
                return $resource->getAuthorUrl();
            case 'provider_name':
                $provider = $resource->getProvider();
                return $provider ? $provider->getName() : '';
            case 'provider_url':
                $provider = $resource->getProvider();
                return $provider ? $provider->getUrl() : NULL;
            case 'cache_age':
                return $resource->getCacheMaxAge();
            case 'thumbnail_width':
                return $resource->getThumbnailWidth();
            case 'thumbnail_height':
                return $resource->getThumbnailHeight();
            case 'url':
                $url = $resource->getUrl();
                return $url ? $url->toString() : NULL;
            case 'width':
                return $resource->getWidth();
            case 'height':
                return $resource->getHeight();
            case 'html':
                return $resource->getHtml();
            default:
                break;
        }
        return NULL;
    }
    
    /**
     * {@inheritdoc}
     */
    public function buildConfigurationForm(array $form, FormStateInterface $form_state) {
        $form = parent::buildConfigurationForm($form, $form_state);
        $domain = $this->configFactory
            ->get('media.settings')
            ->get('iframe_domain');
        if (!$this->iFrameUrlHelper
            ->isSecure($domain)) {
            array_unshift($form, [
                '#markup' => '<p>' . $this->t('It is potentially insecure to display oEmbed content in a frame that is served from the same domain as your main Drupal site, as this may allow execution of third-party code. <a href=":url">You can specify a different domain for serving oEmbed content in the Media settings</a>.', [
                    ':url' => Url::fromRoute('media.settings')->setAbsolute()
                        ->toString(),
                ]) . '</p>',
            ]);
        }
        $form['thumbnails_directory'] = [
            '#type' => 'textfield',
            '#title' => $this->t('Thumbnails location'),
            '#default_value' => $this->configuration['thumbnails_directory'],
            '#description' => $this->t('Thumbnails will be fetched from the provider for local usage. This is the URI of the directory where they will be placed.'),
            '#required' => TRUE,
        ];
        $configuration = $this->getConfiguration();
        $plugin_definition = $this->getPluginDefinition();
        $form['providers'] = [
            '#type' => 'checkboxes',
            '#title' => $this->t('Allowed providers'),
            '#default_value' => $configuration['providers'],
            '#options' => array_combine($plugin_definition['providers'], $plugin_definition['providers']),
            '#description' => $this->t('Optionally select the allowed oEmbed providers for this media type. If left blank, all providers will be allowed.'),
        ];
        return $form;
    }
    
    /**
     * {@inheritdoc}
     */
    public function submitConfigurationForm(array &$form, FormStateInterface $form_state) {
        parent::submitConfigurationForm($form, $form_state);
        $configuration = $this->getConfiguration();
        $configuration['providers'] = array_filter(array_values($configuration['providers']));
        $this->setConfiguration($configuration);
    }
    
    /**
     * {@inheritdoc}
     */
    public function validateConfigurationForm(array &$form, FormStateInterface $form_state) {
        $thumbnails_directory = $form_state->getValue('thumbnails_directory');
        
        /** @var \Drupal\Core\StreamWrapper\StreamWrapperManagerInterface $stream_wrapper_manager */
        $stream_wrapper_manager = \Drupal::service('stream_wrapper_manager');
        if (!$stream_wrapper_manager->isValidUri($thumbnails_directory)) {
            $form_state->setErrorByName('thumbnails_directory', $this->t('@path is not a valid path.', [
                '@path' => $thumbnails_directory,
            ]));
        }
    }
    
    /**
     * {@inheritdoc}
     */
    public function defaultConfiguration() {
        return parent::defaultConfiguration() + [
            'thumbnails_directory' => 'public://oembed_thumbnails/[date:custom:Y-m]',
            'providers' => [],
        ];
    }
    
    /**
     * Returns the local URI for a resource thumbnail.
     *
     * If the thumbnail is not already locally stored, this method will attempt
     * to download it.
     *
     * @param \Drupal\media\OEmbed\Resource $resource
     *   The oEmbed resource.
     * @param \Drupal\media\MediaInterface $media
     *   The media entity that contains the resource.
     *
     * @return string|null
     *   The local thumbnail URI, or NULL if it could not be downloaded, or if the
     *   resource has no thumbnail at all.
     *
     * @todo Determine whether or not oEmbed media thumbnails should be stored
     * locally at all, and if so, whether that functionality should be
     * toggle-able. See https://www.drupal.org/project/drupal/issues/2962751 for
     * more information.
     */
    protected function getLocalThumbnailUri(Resource $resource, MediaInterface $media) {
        $token_data = [
            'date' => $media->getCreatedTime(),
        ];
        // If there is no remote thumbnail, there's nothing for us to fetch here.
        $remote_thumbnail_url = $resource->getThumbnailUrl();
        if (!$remote_thumbnail_url) {
            return NULL;
        }
        // Use the configured directory to store thumbnails. The directory can
        // contain basic (i.e., global) tokens. If any of the replaced tokens
        // contain HTML, the tags will be removed and XML entities will be decoded.
        $configuration = $this->getConfiguration();
        $directory = $configuration['thumbnails_directory'];
        // The thumbnail directory might contain a date token, so we pass in the
        // creation date of the media entity so that the token won't rely on the
        // current request time, making the current request have a max-age of 0.
        // @see system_tokens() for $type == 'date'.
        $directory = $this->token
            ->replace($directory, $token_data);
        $directory = PlainTextOutput::renderFromHtml($directory);
        // The local thumbnail doesn't exist yet, so try to download it. First,
        // ensure that the destination directory is writable, and if it's not,
        // log an error and bail out.
        if (!$this->fileSystem
            ->prepareDirectory($directory, FileSystemInterface::CREATE_DIRECTORY | FileSystemInterface::MODIFY_PERMISSIONS)) {
            $this->logger
                ->warning('Could not prepare thumbnail destination directory @dir for oEmbed media.', [
                '@dir' => $directory,
            ]);
            return NULL;
        }
        // The local filename of the thumbnail is always a hash of its remote URL.
        // If a file with that name already exists in the thumbnails directory,
        // regardless of its extension, return its URI.
        $remote_thumbnail_url = $remote_thumbnail_url->toString();
        $hash = Crypt::hashBase64($remote_thumbnail_url);
        $files = $this->fileSystem
            ->scanDirectory($directory, "/^{$hash}\\..*/");
        if (count($files) > 0) {
            return reset($files)->uri;
        }
        // The local thumbnail doesn't exist yet, so we need to download it.
        try {
            $response = $this->httpClient
                ->request('GET', $remote_thumbnail_url);
            if ($response->getStatusCode() === 200) {
                $local_thumbnail_uri = $directory . DIRECTORY_SEPARATOR . $hash . '.' . $this->getThumbnailFileExtensionFromUrl($remote_thumbnail_url, $response);
                $this->fileSystem
                    ->saveData((string) $response->getBody(), $local_thumbnail_uri, FileExists::Replace);
                return $local_thumbnail_uri;
            }
        } catch (ClientExceptionInterface $e) {
            $this->logger
                ->warning('Failed to download remote thumbnail file due to "%error".', [
                '%error' => $e->getMessage(),
            ]);
        } catch (FileException $e) {
            $this->logger
                ->warning('Could not download remote thumbnail from {url}.', [
                'url' => $remote_thumbnail_url,
            ]);
        }
        return NULL;
    }
    
    /**
     * Tries to determine the file extension of a thumbnail.
     *
     * @param string $thumbnail_url
     *   The remote URL of the thumbnail.
     * @param \Psr\Http\Message\ResponseInterface $response
     *   The response for the downloaded thumbnail.
     *
     * @return string|null
     *   The file extension, or NULL if it could not be determined.
     */
    protected function getThumbnailFileExtensionFromUrl(string $thumbnail_url, ResponseInterface $response) : ?string {
        // First, try to glean the extension from the URL path.
        $path = parse_url($thumbnail_url, PHP_URL_PATH);
        if ($path) {
            $extension = strtolower(pathinfo($path, PATHINFO_EXTENSION));
            if ($extension) {
                return $extension;
            }
        }
        // If the URL didn't give us any clues about the file extension, see if the
        // response headers will give us a MIME type.
        $content_type = $response->getHeader('Content-Type');
        // If there was no Content-Type header, there's nothing else we can do.
        if (empty($content_type)) {
            return NULL;
        }
        $extensions = MimeTypes::getDefault()->getExtensions(reset($content_type));
        if ($extensions) {
            return reset($extensions);
        }
        // If no file extension could be determined from the Content-Type header,
        // we're stumped.
        return NULL;
    }
    
    /**
     * {@inheritdoc}
     */
    public function getSourceFieldConstraints() {
        return [
            'oembed_resource' => [],
        ];
    }
    
    /**
     * {@inheritdoc}
     */
    public function prepareViewDisplay(MediaTypeInterface $type, EntityViewDisplayInterface $display) {
        $display->setComponent($this->getSourceFieldDefinition($type)
            ->getName(), [
            'type' => 'oembed',
            'label' => 'visually_hidden',
        ]);
    }
    
    /**
     * {@inheritdoc}
     */
    public function prepareFormDisplay(MediaTypeInterface $type, EntityFormDisplayInterface $display) {
        parent::prepareFormDisplay($type, $display);
        $source_field = $this->getSourceFieldDefinition($type)
            ->getName();
        $display->setComponent($source_field, [
            'type' => 'oembed_textfield',
            'weight' => $display->getComponent($source_field)['weight'],
        ]);
        $display->removeComponent('name');
    }
    
    /**
     * {@inheritdoc}
     */
    public function getProviders() {
        $configuration = $this->getConfiguration();
        return $configuration['providers'] ?: $this->getPluginDefinition()['providers'];
    }
    
    /**
     * {@inheritdoc}
     */
    public function createSourceField(MediaTypeInterface $type) {
        $plugin_definition = $this->getPluginDefinition();
        $label = (string) $this->t('@type URL', [
            '@type' => $plugin_definition['label'],
        ]);
        return parent::createSourceField($type)->set('label', $label);
    }

}