gnu-social/plugins/Embed/Embed.php
2021-09-14 13:13:26 +01:00

503 lines
18 KiB
PHP

<?php
// {{{ License
// This file is part of GNU social - https://www.gnu.org/software/social
//
// GNU social is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// GNU social is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with GNU social. If not, see <http://www.gnu.org/licenses/>.
// }}}
/**
* OEmbed and OpenGraph implementation for GNU social
*
* @package GNUsocial
*
* @author Mikael Nordfeldth
* @author Stephen Paul Weber
* @author hannes
* @author Mikael Nordfeldth
* @author Miguel Dantas
* @author Hugo Sales <hugo@hsal.es>
* @author Diogo Peralta Cordeiro <mail@diogo.site>
* @copyright 2014-2021 Free Software Foundation, Inc http://www.fsf.org
* @license https://www.gnu.org/licenses/agpl.html GNU AGPL v3 or later
*/
namespace Plugin\Embed;
use App\Core\Cache;
use App\Core\DB\DB;
use App\Core\Event;
use App\Core\GSFile;
use App\Core\HTTPClient;
use function App\Core\I18n\_m;
use App\Core\Log;
use App\Core\Modules\Plugin;
use App\Core\Router\RouteLoader;
use App\Core\Router\Router;
use App\Entity\Attachment;
use App\Entity\Note;
use App\Entity\RemoteURL;
use App\Util\Common;
use App\Util\Exception\DuplicateFoundException;
use App\Util\Exception\NotFoundException;
use App\Util\Exception\ServerException;
use App\Util\Exception\TemporaryFileException;
use App\Util\Formatting;
use App\Util\TemporaryFile;
use Embed\Embed as LibEmbed;
use Exception;
use Symfony\Component\HttpFoundation\Request;
/**
* Base class for the Embed plugin that does most of the heavy lifting to get
* and display representations for remote content.
*
* @copyright 2014-2021 Free Software Foundation, Inc http://www.fsf.org
* @license https://www.gnu.org/licenses/agpl.html GNU AGPL v3 or later
*/
class Embed extends Plugin
{
public function version(): string
{
return '3.0.0';
}
/**
* Settings which can be set in social.local.yaml
* WARNING, these are _regexps_ (slashes added later). Always escape your dots and end ('$') your strings
*/
public array $domain_whitelist = [
// hostname => service provider
'.*' => '', // Default to allowing any host
];
/**
* This code executes when GNU social creates the page routing, and we hook
* on this event to add our action handler for Embed.
*
* @param $m RouteLoader the router that was initialized.
*
* @throws Exception
*
* @return bool
*
*/
public function onAddRoute(RouteLoader $m): bool
{
$m->connect('oembed', 'main/oembed', Controller\Embed::class);
$m->connect('embed', 'main/embed', Controller\Embed::class);
return Event::next;
}
/**
* Insert oembed and opengraph tags in all HTML head elements
*/
public function onShowHeadElements(Request $request, array &$result)
{
$matches = [];
preg_match(',/?([^/]+)/?(.*),', $request->getPathInfo(), $matches);
switch ($matches[1]) {
case 'attachment':
$url = "{$matches[1]}/{$matches[2]}";
break;
}
if (isset($url)) {
foreach (['xml', 'json'] as $format) {
$result[] = [
'link' => [
'rel' => 'alternate',
'type' => "application/{$format}+oembed",
'href' => Router::url('embed', ['format' => $format, 'url' => $url]),
'title' => 'oEmbed',
], ];
}
}
return Event::next;
}
/**
* Save embedding information for an Attachment, if applicable.
*
* @param RemoteURL $remote_url
* @param Note $note
*
* @throws DuplicateFoundException
* @throws ServerException
* @throws TemporaryFileException
*
* @return bool
*/
public function onNewRemoteURLFromNote(RemoteURL $remote_url, Note $note): bool
{
// Only handle text mime
if ($remote_url->getMimetypeMajor() !== 'text') {
return Event::next;
}
// Ignore if already handled
$attachment_embed = DB::find('attachment_embed', ['remoteurl_id' => $remote_url->getId()]);
if (!is_null($attachment_embed)) {
return Event::next;
}
$mimetype = $remote_url->getMimetype();
if (Formatting::startsWith($mimetype, 'text/html') || Formatting::startsWith($mimetype, 'application/xhtml+xml')) {
try {
$embed_data = $this->getEmbed($remote_url->getRemoteUrl());
$embed_data['remoteurl_id'] = $remote_url->getId();
// Create attachment
$embed_data['attachment_id'] = $attachment->getId();
DB::persist(Entity\AttachmentEmbed::create($embed_data));
DB::flush();
} catch (Exception $e) {
Log::warning($e);
}
}
return Event::next;
}
/**
* Perform an oEmbed or OpenGraph lookup for the given $url.
*
* Some known hosts are whitelisted with API endpoints where we
* know they exist but autodiscovery data isn't available.
*
* Throws exceptions on failure.
*
* @param string $url
*
* @return array
*/
public function getEmbed(string $url): array
{
Log::info('Checking for remote URL metadata for ' . $url);
try {
Log::info("Trying to find Embed data for {$url} with 'oscarotero/Embed'");
$embed = new LibEmbed();
$info = $embed->get($url);
$metadata['title'] = $info->title;
$metadata['description'] = $info->description;
$metadata['author_name'] = $info->authorName;
$metadata['author_url'] = (string) $info->authorUrl;
$metadata['provider_name'] = $info->providerName;
$metadata['provider_url'] = (string) $info->providerUrl;
if (!is_null($info->image)) {
$thumbnail_url = (string) $info->image;
} else {
$thumbnail_url = (string) $info->favicon;
}
// Check thumbnail URL validity
$metadata['thumbnail_url'] = $thumbnail_url;
} catch (Exception $e) {
Log::info("Failed to find Embed data for {$url} with 'oscarotero/Embed', got exception: " . $e->getMessage());
}
$metadata = self::normalize($metadata);
return $metadata;
}
/**
* Normalize fetched info.
*
* @param array $metadata
*
* @return array
*/
public static function normalize(array $metadata): array
{
if (isset($metadata['thumbnail_url'])) {
// sometimes sites serve the path, not the full URL, for images
// let's "be liberal in what you accept from others"!
// add protocol and host if the thumbnail_url starts with /
if ($metadata['thumbnail_url'][0] == '/') {
$thumbnail_url_parsed = parse_url($metadata['thumbnail_url']);
$metadata['thumbnail_url'] = "{$thumbnail_url_parsed['scheme']}://{$thumbnail_url_parsed['host']}{$metadata['url']}";
}
// Some wordpress opengraph implementations sometimes return a white blank image
// no need for us to save that!
if ($metadata['thumbnail_url'] == 'https://s0.wp.com/i/blank.jpg') {
$metadata['thumbnail_url'] = null;
}
}
return $metadata;
}
/**
* Show this attachment enhanced with the corresponding Embed data, if available
*
* @param array $vars
* @param array $res
*
* @return bool
*/
public function onViewAttachmentText(array $vars, array &$res): bool
{
$attachment = $vars['attachment'];
try {
$embed = Cache::get('attachment-embed-' . $attachment->getId(),
fn () => DB::findOneBy('attachment_embed', ['attachment_id' => $attachment->getId()]));
} catch (DuplicateFoundException $e) {
Log::warning($e);
return Event::next;
} catch (NotFoundException) {
return Event::next;
}
if (is_null($embed) && empty($embed->getAuthorName()) && empty($embed->getProviderName())) {
Log::debug('Embed doesn\'t have a representation for the attachment #' . $attachment->getId());
return Event::next;
}
$attributes = $embed->getImageHTMLAttributes(['class' => 'u-photo embed']);
$res[] = Formatting::twigRenderString(<<<END
<article class="h-entry embed">
<header>
{% if attributes != false %}
<img class="u-photo embed" width="{{attributes['width']}}" height="{{attributes['height']}}" src="{{attributes['src']}}" />
{% endif %}
<h5 class="p-name embed">
<a class="u-url" href="{{attachment.getRemoteUrl()}}">{{embed.getTitle() | escape}}</a>
</h5>
<div class="p-author embed">
{% if embed.getAuthorName() is not null %}
<div class="fn vcard author">
{% if embed.getAuthorUrl() is null %}
<p>{{embed.getAuthorName()}}</p>
{% else %}
<a href="{{embed.getAuthorUrl()}}" class="url">{{embed.getAuthorName()}}</a>
{% endif %}
</div>
{% endif %}
{% if embed.getProviderName() is not null %}
<div class="fn vcard">
{% if embed.getProviderUrl() is null %}
<p>{{embed.getProviderName()}}</p>
{% else %}
<a href="{{embed.getProviderUrl()}}" class="url">{{embed.getProviderName()}}</a>
{% endif %}
</div>
{% endif %}
</div>
</header>
<div class="p-summary embed">
{{ embed.getHtml() | escape }}
</div>
</article>
END, ['embed' => $embed, 'attributes' => $attributes, 'attachment' => $attachment]);
return Event::stop;
}
/**
* @throws ServerException if check is made but fails
*
* @return bool false on no check made, provider name on success
* @return false|string on no check made, provider name on success
*
*
*/
protected function checkWhitelist(string $url): string | bool
{
if ($this->check_whitelist ?? false) {
return false; // indicates "no check made"
}
$host = parse_url($url, PHP_URL_HOST);
foreach ($this->domain_whitelist as $regex => $provider) {
if (preg_match("/{$regex}/", $host)) {
return $provider; // we trust this source, return provider name
}
}
throw new ServerException(_m('Domain not in remote thumbnail source whitelist: {host}', ['host' => $host]));
}
/**
* Check the file size of a remote file using a HEAD request and checking
* the content-length variable returned. This isn't 100% foolproof but is
* reliable enough for our purposes.
*
* @param string $url
* @param null|array $headers - if we already made a request
*
* @return null|int the file size if it succeeds, false otherwise.
*/
private function getRemoteFileSize(string $url, ?array $headers = null): ?int
{
try {
if ($headers === null) {
if (!Common::isValidHttpUrl($url)) {
Log::error('Invalid URL in Embed::getRemoteFileSize()');
return false;
}
$head = HTTPClient::head($url);
$headers = $head->getHeaders();
$headers = array_change_key_case($headers, CASE_LOWER);
}
return $headers['content-length'][0] ?? false;
} catch (Exception $e) {
Loog::error($e);
return false;
}
}
/**
* A private helper function that uses a HEAD request to check the mimetype
* of a remote URL to see if it's an image.
*
* @param mixed $url
* @param null|mixed $headers
*
* @return bool true if the remote URL is an image, or false otherwise.
*/
private function isRemoteImage(string $url, ?array $headers = null): bool
{
try {
if ($headers === null) {
if (!Common::isValidHttpUrl($url)) {
Log::error('Invalid URL in Embed::getRemoteFileSize()');
return false;
}
$head = HTTPClient::head($url);
$headers = $head->getHeaders();
$headers = array_change_key_case($headers, CASE_LOWER);
}
return !empty($headers['content-type']) && GSFile::mimetypeMajor($headers['content-type'][0]) === 'image';
} catch (Exception $e) {
Log::error($e);
return false;
}
}
/**
* Validate that $imgData is a valid image, place it in its folder and resize
*
* @param $imgData - The image data to validate
* @param null|array $headers - The headers possible previous request to $url
*/
protected function validateAndWriteImage($imgData, ?array $headers = null): array
{
$file = new TemporaryFile();
$file->write($imgData);
Event::handle('HashFile', [$file->getRealPath(), &$hash]);
$filepath = Common::config('storage', 'dir') . "embed/{$hash}" . Common::config('thumbnail', 'extension');
$width = Common::config('plugin_embed', 'width');
$height = Common::config('plugin_embed', 'height');
$smart_crop = Common::config('plugin_embed', 'smart_crop');
Event::handle('ResizeImagePath', [$file->getRealPath(), $filepath, &$width, &$height, $smart_crop, &$mimetype]);
unset($file);
if (!is_null($headers) && array_key_exists('content-disposition', $headers) && preg_match('/^.+; filename="(.+?)"$/', $headers['content-disposition'][0], $matches) === 1) {
$original_name = $matches[1];
}
return [$filepath, $width, $height, $original_name ?? null, $mimetype];
}
/**
* Fetch, Validate and Write a remote image from url to temporary file
*
* @param Attachment $attachment
* @param string $media_url URL for the actual media representation
*
* @throws Exception
*
* @return array|bool
*/
protected function fetchValidateWriteRemoteImage(Attachment $attachment, string $media_url): array | bool
{
if ($attachment->hasFilename() && file_exists($attachment->getPath())) {
throw new AlreadyFulfilledException(_m('A thumbnail seems to already exist for remote file with id=={id}', ['id' => $attachment->getId()]));
}
if (Formatting::startsWith($media_url, 'file://')) {
$filename = Formatting::removePrefix($media_url, 'file://');
$info = getimagesize($filename);
$filename = basename($filename);
$width = $info[0];
$height = $info[1];
} else {
$this->checkWhitelist($media_url);
$head = HTTPClient::head($media_url);
$headers = $head->getHeaders();
$headers = array_change_key_case($headers, CASE_LOWER);
try {
$is_image = $this->isRemoteImage($media_url, $headers);
if ($is_image == true) {
$file_size = $this->getRemoteFileSize($media_url, $headers);
$max_size = Common::config('attachments', 'file_quota');
if (($file_size != false) && ($file_size > $max_size)) {
throw new \Exception("Wanted to store remote thumbnail of size {$file_size} but the upload limit is {$max_size} so we aborted.");
}
} else {
return false;
}
} catch (Exception $err) {
Log::debug('Could not determine size of remote image, aborted local storage.');
throw $err;
}
// First we download the file to memory and test whether it's actually an image file
Log::debug('Downloading remote thumbnail for file id==' . $attachment->getId() . " with thumbnail URL: {$media_url}");
try {
$imgData = HTTPClient::get($media_url)->getContent();
if (isset($imgData)) {
[$filepath, $width, $height, $original_name, $mimetype] = $this->validateAndWriteImage($imgData, $headers);
} else {
throw new UnsupportedMediaException(_m('HTTPClient returned an empty result'));
}
} catch (UnsupportedMediaException $e) {
// Couldn't find anything that looks like an image, nothing to do
Log::debug($e);
return false;
}
}
return [$filepath, $width, $height, $original_name, $mimetype];
}
/**
* Event raised when GNU social polls the plugin for information about it.
* Adds this plugin's version information to $versions array
*
* @param &$versions array inherited from parent
*
* @return bool true hook value
*/
public function onPluginVersion(array &$versions): bool
{
$versions[] = [
'name' => 'Embed',
'version' => $this->version(),
'author' => 'Mikael Nordfeldth, Hugo Sales, Diogo Peralta Cordeiro',
'homepage' => GNUSOCIAL_PROJECT_URL,
'description' => // TRANS: Plugin description.
_m('Plugin for using and representing oEmbed, OpenGraph and other data.'),
];
return Event::next;
}
}