gnu-social/plugins/Oembed/OembedPlugin.php
2016-02-25 22:31:45 +01:00

361 lines
15 KiB
PHP

<?php
if (!defined('GNUSOCIAL')) { exit(1); }
class OembedPlugin extends Plugin
{
// settings which can be set in config.php with addPlugin('Oembed', array('param'=>'value', ...));
// WARNING, these are _regexps_ (slashes added later). Always escape your dots and end your strings
public $domain_whitelist = array( // hostname => service provider
'^i\d*\.ytimg\.com$' => 'YouTube',
'^i\d*\.vimeocdn\.com$' => 'Vimeo',
);
public $append_whitelist = array(); // fill this array as domain_whitelist to add more trusted sources
public $check_whitelist = false; // security/abuse precaution
protected $imgData = array();
// these should be declared protected everywhere
public function initialize()
{
parent::initialize();
$this->domain_whitelist = array_merge($this->domain_whitelist, $this->append_whitelist);
}
public function onCheckSchema()
{
$schema = Schema::get();
$schema->ensureTable('file_oembed', File_oembed::schemaDef());
return true;
}
public function onRouterInitialized(URLMapper $m)
{
$m->connect('main/oembed', array('action' => 'oembed'));
}
public function onGetRemoteUrlMetadataFromDom($url, DOMDocument $dom, stdClass &$metadata)
{
try {
common_log(LOG_INFO, 'Trying to discover an oEmbed endpoint using link headers.');
$api = oEmbedHelper::oEmbedEndpointFromHTML($dom);
common_log(LOG_INFO, 'Found oEmbed API endpoint ' . $api . ' for URL ' . $url);
$params = array(
'maxwidth' => common_config('thumbnail', 'width'),
'maxheight' => common_config('thumbnail', 'height'),
);
$metadata = oEmbedHelper::getOembedFrom($api, $url, $params);
// Facebook just gives us javascript in its oembed html,
// so use the content of the title element instead
if(strpos($url,'https://www.facebook.com/') === 0) {
$metadata->html = @$dom->getElementsByTagName('title')->item(0)->nodeValue;
}
// Wordpress sometimes also just gives us javascript, use og:description if it is available
$xpath = new DomXpath($dom);
$generatorNode = @$xpath->query('//meta[@name="generator"][1]')->item(0);
if ($generatorNode instanceof DomElement) {
// when wordpress only gives us javascript, the html stripped from tags
// is the same as the title, so this helps us to identify this (common) case
if(strpos($generatorNode->getAttribute('content'),'WordPress') === 0
&& trim(strip_tags($metadata->html)) == trim($metadata->title)) {
$propertyNode = @$xpath->query('//meta[@property="og:description"][1]')->item(0);
if ($propertyNode instanceof DomElement) {
$metadata->html = $propertyNode->getAttribute('content');
}
}
}
} catch (Exception $e) {
common_log(LOG_INFO, 'Could not find an oEmbed endpoint using link headers, trying OpenGraph from HTML.');
// Just ignore it!
$metadata = OpenGraphHelper::ogFromHtml($dom);
}
if (isset($metadata->thumbnail_url)) {
// sometimes sites serve the path, not the full URL, for images
// let's "be liberal in what you accept from others"!
// add protocol and host if the thumbnail_url starts with /
if(substr($metadata->thumbnail_url,0,1) == '/') {
$thumbnail_url_parsed = parse_url($metadata->url);
$metadata->thumbnail_url = $thumbnail_url_parsed['scheme']."://".$thumbnail_url_parsed['host'].$metadata->thumbnail_url;
}
// some wordpress opengraph implementations sometimes return a white blank image
// no need for us to save that!
if($metadata->thumbnail_url == 'https://s0.wp.com/i/blank.jpg') {
unset($metadata->thumbnail_url);
}
}
}
public function onEndShowHeadElements(Action $action)
{
switch ($action->getActionName()) {
case 'attachment':
$action->element('link',array('rel'=>'alternate',
'type'=>'application/json+oembed',
'href'=>common_local_url(
'oembed',
array(),
array('format'=>'json', 'url'=>
common_local_url('attachment',
array('attachment' => $action->attachment->id)))),
'title'=>'oEmbed'),null);
$action->element('link',array('rel'=>'alternate',
'type'=>'text/xml+oembed',
'href'=>common_local_url(
'oembed',
array(),
array('format'=>'xml','url'=>
common_local_url('attachment',
array('attachment' => $action->attachment->id)))),
'title'=>'oEmbed'),null);
break;
case 'shownotice':
if (!$action->notice->isLocal()) {
break;
}
try {
$action->element('link',array('rel'=>'alternate',
'type'=>'application/json+oembed',
'href'=>common_local_url(
'oembed',
array(),
array('format'=>'json','url'=>$action->notice->getUrl())),
'title'=>'oEmbed'),null);
$action->element('link',array('rel'=>'alternate',
'type'=>'text/xml+oembed',
'href'=>common_local_url(
'oembed',
array(),
array('format'=>'xml','url'=>$action->notice->getUrl())),
'title'=>'oEmbed'),null);
} catch (InvalidUrlException $e) {
// The notice is probably a share or similar, which don't
// have a representational URL of their own.
}
break;
}
return true;
}
/**
* Save embedding information for a File, if applicable.
*
* Normally this event is called through File::saveNew()
*
* @param File $file The newly inserted File object.
*
* @return boolean success
*/
public function onEndFileSaveNew(File $file)
{
$fo = File_oembed::getKV('file_id', $file->id);
if ($fo instanceof File_oembed) {
common_log(LOG_WARNING, "Strangely, a File_oembed object exists for new file {$file->id}", __FILE__);
return true;
}
if (isset($file->mimetype)
&& (('text/html' === substr($file->mimetype, 0, 9)
|| 'application/xhtml+xml' === substr($file->mimetype, 0, 21)))) {
try {
$oembed_data = File_oembed::_getOembed($file->url);
if ($oembed_data === false) {
throw new Exception('Did not get oEmbed data from URL');
}
} catch (Exception $e) {
return true;
}
File_oembed::saveNew($oembed_data, $file->id);
}
return true;
}
public function onEndShowAttachmentLink(HTMLOutputter $out, File $file)
{
$oembed = File_oembed::getKV('file_id', $file->id);
if (empty($oembed->author_name) && empty($oembed->provider)) {
return true;
}
$out->elementStart('div', array('id'=>'oembed_info', 'class'=>'e-content'));
if (!empty($oembed->author_name)) {
$out->elementStart('div', 'fn vcard author');
if (empty($oembed->author_url)) {
$out->text($oembed->author_name);
} else {
$out->element('a', array('href' => $oembed->author_url,
'class' => 'url'),
$oembed->author_name);
}
}
if (!empty($oembed->provider)) {
$out->elementStart('div', 'fn vcard');
if (empty($oembed->provider_url)) {
$out->text($oembed->provider);
} else {
$out->element('a', array('href' => $oembed->provider_url,
'class' => 'url'),
$oembed->provider);
}
}
$out->elementEnd('div');
}
public function onFileEnclosureMetadata(File $file, &$enclosure)
{
// Never treat generic HTML links as an enclosure type!
// But if we have oEmbed info, we'll consider it golden.
$oembed = File_oembed::getKV('file_id', $file->id);
if (!$oembed instanceof File_oembed || !in_array($oembed->type, array('photo', 'video'))) {
return true;
}
foreach (array('mimetype', 'url', 'title', 'modified', 'width', 'height') as $key) {
if (isset($oembed->{$key}) && !empty($oembed->{$key})) {
$enclosure->{$key} = $oembed->{$key};
}
}
return true;
}
public function onShowUnsupportedAttachmentRepresentation(HTMLOutputter $out, File $file)
{
try {
$oembed = File_oembed::getByFile($file);
} catch (NoResultException $e) {
return true;
}
// the 'photo' type is shown through ordinary means, using StartShowAttachmentRepresentation!
switch ($oembed->type) {
case 'video':
case 'link':
if (!empty($oembed->html)
&& (GNUsocial::isAjax() || common_config('attachments', 'show_html'))) {
require_once INSTALLDIR.'/extlib/HTMLPurifier/HTMLPurifier.auto.php';
$purifier = new HTMLPurifier();
// FIXME: do we allow <object> and <embed> here? we did that when we used htmLawed, but I'm not sure anymore...
$out->raw($purifier->purify($oembed->html));
}
return false;
break;
}
return true;
}
public function onCreateFileImageThumbnailSource(File $file, &$imgPath, $media=null)
{
// If we are on a private node, we won't do any remote calls (just as a precaution until
// we can configure this from config.php for the private nodes)
if (common_config('site', 'private')) {
return true;
}
// All our remote Oembed images lack a local filename property in the File object
if (!is_null($file->filename)) {
return true;
}
try {
// If we have proper oEmbed data, there should be an entry in the File_oembed
// and File_thumbnail tables respectively. If not, we're not going to do anything.
$file_oembed = File_oembed::getByFile($file);
$thumbnail = File_thumbnail::byFile($file);
} catch (NoResultException $e) {
// Not Oembed data, or at least nothing we either can or want to use.
return true;
}
try {
$this->storeRemoteFileThumbnail($thumbnail);
} catch (AlreadyFulfilledException $e) {
// aw yiss!
}
$imgPath = $thumbnail->getPath();
return false;
}
/**
* @return boolean false on no check made, provider name on success
* @throws ServerException if check is made but fails
*/
protected function checkWhitelist($url)
{
if (!$this->check_whitelist) {
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(sprintf(_('Domain not in remote thumbnail source whitelist: %s'), $host));
}
protected function storeRemoteFileThumbnail(File_thumbnail $thumbnail)
{
if (!empty($thumbnail->filename) && file_exists($thumbnail->getPath())) {
throw new AlreadyFulfilledException(sprintf('A thumbnail seems to already exist for remote file with id==%u', $thumbnail->file_id));
}
$url = $thumbnail->getUrl();
$this->checkWhitelist($url);
// First we download the file to memory and test whether it's actually an image file
// FIXME: To support remote video/whatever files, this needs reworking.
common_debug(sprintf('Downloading remote thumbnail for file id==%u with thumbnail URL: %s', $thumbnail->file_id, $url));
$imgData = HTTPClient::quickGet($url);
$info = @getimagesizefromstring($imgData);
if ($info === false) {
throw new UnsupportedMediaException(_('Remote file format was not identified as an image.'), $url);
} elseif (!$info[0] || !$info[1]) {
throw new UnsupportedMediaException(_('Image file had impossible geometry (0 width or height)'));
}
$ext = File::guessMimeExtension($info['mime']);
// We'll trust sha256 (File::FILEHASH_ALG) not to have collision issues any time soon :)
$filename = hash(File::FILEHASH_ALG, $imgData) . ".{$ext}";
$fullpath = File_thumbnail::path($filename);
// Write the file to disk. Throw Exception on failure
if (!file_exists($fullpath) && file_put_contents($fullpath, $imgData) === false) {
throw new ServerException(_('Could not write downloaded file to disk.'));
}
// Get rid of the file from memory
unset($imgData);
// Updated our database for the file record
$orig = clone($thumbnail);
$thumbnail->filename = $filename;
$thumbnail->width = $info[0]; // array indexes documented on php.net:
$thumbnail->height = $info[1]; // https://php.net/manual/en/function.getimagesize.php
// Throws exception on failure.
$thumbnail->updateWithKeys($orig);
}
public function onPluginVersion(array &$versions)
{
$versions[] = array('name' => 'Oembed',
'version' => GNUSOCIAL_VERSION,
'author' => 'Mikael Nordfeldth',
'homepage' => 'http://gnu.io/',
'description' =>
// TRANS: Plugin description.
_m('Plugin for using and representing Oembed data.'));
return true;
}
}