319 lines
9.9 KiB
PHP
319 lines
9.9 KiB
PHP
<?php
|
|
/*
|
|
* StatusNet - the distributed open-source microblogging tool
|
|
* Copyright (C) 2008-2010, StatusNet, Inc.
|
|
*
|
|
* This program 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.
|
|
*
|
|
* This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
if (!defined('STATUSNET')) {
|
|
exit(1);
|
|
}
|
|
|
|
|
|
/**
|
|
* Utility class to wrap basic oEmbed lookups.
|
|
*
|
|
* Blacklisted hosts will use an alternate lookup method:
|
|
* - Twitpic
|
|
*
|
|
* Whitelisted hosts will use known oEmbed API endpoints:
|
|
* - Flickr, YFrog
|
|
*
|
|
* Sites that provide discovery links will use them directly; a bug
|
|
* in use of discovery links with query strings is worked around.
|
|
*
|
|
* Others will fall back to oohembed (unless disabled).
|
|
* The API endpoint can be configured or disabled through config
|
|
* as 'oohembed'/'endpoint'.
|
|
*/
|
|
class oEmbedHelper
|
|
{
|
|
protected static $apiMap = array(
|
|
'flickr.com' => 'http://www.flickr.com/services/oembed/',
|
|
'yfrog.com' => 'http://www.yfrog.com/api/oembed',
|
|
);
|
|
protected static $functionMap = array(
|
|
'twitpic.com' => 'oEmbedHelper::twitPic',
|
|
);
|
|
|
|
/**
|
|
* Perform or fake an oEmbed lookup for the given resource.
|
|
*
|
|
* Some known hosts are whitelisted with API endpoints where we
|
|
* know they exist but autodiscovery data isn't available.
|
|
* If autodiscovery links are missing and we don't recognize the
|
|
* host, we'll pass it to oohembed.com's public service which
|
|
* will either proxy or fake info on a lot of sites.
|
|
*
|
|
* A few hosts are blacklisted due to known problems with oohembed,
|
|
* in which case we'll look up the info another way and return
|
|
* equivalent data.
|
|
*
|
|
* Throws exceptions on failure.
|
|
*
|
|
* @param string $url
|
|
* @param array $params
|
|
* @return object
|
|
*/
|
|
public static function getObject($url, $params=array())
|
|
{
|
|
$host = parse_url($url, PHP_URL_HOST);
|
|
if (substr($host, 0, 4) == 'www.') {
|
|
$host = substr($host, 4);
|
|
}
|
|
|
|
// Blacklist: systems with no oEmbed API of their own, which are
|
|
// either missing from or broken on oohembed.com's proxy.
|
|
// we know how to look data up in another way...
|
|
if (array_key_exists($host, self::$functionMap)) {
|
|
$func = self::$functionMap[$host];
|
|
return call_user_func($func, $url, $params);
|
|
}
|
|
|
|
// Whitelist: known API endpoints for sites that don't provide discovery...
|
|
if (array_key_exists($host, self::$apiMap)) {
|
|
$api = self::$apiMap[$host];
|
|
} else {
|
|
try {
|
|
$api = self::discover($url);
|
|
} catch (Exception $e) {
|
|
// Discovery failed... fall back to oohembed if enabled.
|
|
$oohembed = common_config('oohembed', 'endpoint');
|
|
if ($oohembed) {
|
|
$api = $oohembed;
|
|
} else {
|
|
throw $e;
|
|
}
|
|
}
|
|
}
|
|
return self::getObjectFrom($api, $url, $params);
|
|
}
|
|
|
|
/**
|
|
* Perform basic discovery.
|
|
* @return string
|
|
*/
|
|
static function discover($url)
|
|
{
|
|
// @fixme ideally skip this for non-HTML stuff!
|
|
$body = self::http($url);
|
|
return self::discoverFromHTML($url, $body);
|
|
}
|
|
|
|
/**
|
|
* Partially ripped from OStatus' FeedDiscovery class.
|
|
*
|
|
* @param string $url source URL, used to resolve relative links
|
|
* @param string $body HTML body text
|
|
* @return mixed string with URL or false if no target found
|
|
*/
|
|
static function discoverFromHTML($url, $body)
|
|
{
|
|
// DOMDocument::loadHTML may throw warnings on unrecognized elements,
|
|
// and notices on unrecognized namespaces.
|
|
$old = error_reporting(error_reporting() & ~(E_WARNING | E_NOTICE));
|
|
$dom = new DOMDocument();
|
|
$ok = $dom->loadHTML($body);
|
|
error_reporting($old);
|
|
|
|
if (!$ok) {
|
|
throw new oEmbedHelper_BadHtmlException();
|
|
}
|
|
|
|
// Ok... now on to the links!
|
|
$feeds = array(
|
|
'application/json+oembed' => false,
|
|
);
|
|
|
|
$nodes = $dom->getElementsByTagName('link');
|
|
for ($i = 0; $i < $nodes->length; $i++) {
|
|
$node = $nodes->item($i);
|
|
if ($node->hasAttributes()) {
|
|
$rel = $node->attributes->getNamedItem('rel');
|
|
$type = $node->attributes->getNamedItem('type');
|
|
$href = $node->attributes->getNamedItem('href');
|
|
if ($rel && $type && $href) {
|
|
$rel = array_filter(explode(" ", $rel->value));
|
|
$type = trim($type->value);
|
|
$href = trim($href->value);
|
|
|
|
if (in_array('alternate', $rel) && array_key_exists($type, $feeds) && empty($feeds[$type])) {
|
|
// Save the first feed found of each type...
|
|
$feeds[$type] = $href;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Return the highest-priority feed found
|
|
foreach ($feeds as $type => $url) {
|
|
if ($url) {
|
|
return $url;
|
|
}
|
|
}
|
|
|
|
throw new oEmbedHelper_DiscoveryException();
|
|
}
|
|
|
|
/**
|
|
* Actually do an oEmbed lookup to a particular API endpoint.
|
|
*
|
|
* @param string $api oEmbed API endpoint URL
|
|
* @param string $url target URL to look up info about
|
|
* @param array $params
|
|
* @return object
|
|
*/
|
|
static function getObjectFrom($api, $url, $params=array())
|
|
{
|
|
$params['url'] = $url;
|
|
$params['format'] = 'json';
|
|
$data = self::json($api, $params);
|
|
return self::normalize($data);
|
|
}
|
|
|
|
/**
|
|
* Normalize oEmbed format.
|
|
*
|
|
* @param object $orig
|
|
* @return object
|
|
*/
|
|
static function normalize($orig)
|
|
{
|
|
$data = clone($orig);
|
|
|
|
if (empty($data->type)) {
|
|
throw new Exception('Invalid oEmbed data: no type field.');
|
|
}
|
|
|
|
if ($data->type == 'image') {
|
|
// YFrog does this.
|
|
$data->type = 'photo';
|
|
}
|
|
|
|
if (isset($data->thumbnail_url)) {
|
|
if (!isset($data->thumbnail_width)) {
|
|
// !?!?!
|
|
$data->thumbnail_width = common_config('attachments', 'thumb_width');
|
|
$data->thumbnail_height = common_config('attachments', 'thumb_height');
|
|
}
|
|
}
|
|
|
|
return $data;
|
|
}
|
|
|
|
/**
|
|
* Using a local function for twitpic lookups, as oohembed's adapter
|
|
* doesn't return a valid result:
|
|
* http://code.google.com/p/oohembed/issues/detail?id=19
|
|
*
|
|
* This code fetches metadata from Twitpic's own API, and attempts
|
|
* to guess proper thumbnail size from the original's size.
|
|
*
|
|
* @todo respect maxwidth and maxheight params
|
|
*
|
|
* @param string $url
|
|
* @param array $params
|
|
* @return object
|
|
*/
|
|
static function twitPic($url, $params=array())
|
|
{
|
|
$matches = array();
|
|
if (preg_match('!twitpic\.com/(\w+)!', $url, $matches)) {
|
|
$id = $matches[1];
|
|
} else {
|
|
throw new Exception("Invalid twitpic URL");
|
|
}
|
|
|
|
// Grab metadata from twitpic's API...
|
|
// http://dev.twitpic.com/docs/2/media_show
|
|
$data = self::json('http://api.twitpic.com/2/media/show.json',
|
|
array('id' => $id));
|
|
$oembed = (object)array('type' => 'photo',
|
|
'url' => 'http://twitpic.com/show/full/' . $data->short_id,
|
|
'width' => $data->width,
|
|
'height' => $data->height);
|
|
if (!empty($data->message)) {
|
|
$oembed->title = $data->message;
|
|
}
|
|
|
|
// Thumbnail is cropped and scaled to 150x150 box:
|
|
// http://dev.twitpic.com/docs/thumbnails/
|
|
$thumbSize = 150;
|
|
$oembed->thumbnail_url = 'http://twitpic.com/show/thumb/' . $data->short_id;
|
|
$oembed->thumbnail_width = $thumbSize;
|
|
$oembed->thumbnail_height = $thumbSize;
|
|
|
|
return $oembed;
|
|
}
|
|
|
|
/**
|
|
* Fetch some URL and return JSON data.
|
|
*
|
|
* @param string $url
|
|
* @param array $params query-string params
|
|
* @return object
|
|
*/
|
|
static protected function json($url, $params=array())
|
|
{
|
|
$data = self::http($url, $params);
|
|
return json_decode($data);
|
|
}
|
|
|
|
/**
|
|
* Hit some web API and return data on success.
|
|
* @param string $url
|
|
* @param array $params
|
|
* @return string
|
|
*/
|
|
static protected function http($url, $params=array())
|
|
{
|
|
$client = HTTPClient::start();
|
|
if ($params) {
|
|
$query = http_build_query($params, null, '&');
|
|
if (strpos($url, '?') === false) {
|
|
$url .= '?' . $query;
|
|
} else {
|
|
$url .= '&' . $query;
|
|
}
|
|
}
|
|
$response = $client->get($url);
|
|
if ($response->isOk()) {
|
|
return $response->getBody();
|
|
} else {
|
|
throw new Exception('Bad HTTP response code: ' . $response->getStatus());
|
|
}
|
|
}
|
|
}
|
|
|
|
class oEmbedHelper_Exception extends Exception
|
|
{
|
|
}
|
|
|
|
class oEmbedHelper_BadHtmlException extends oEmbedHelper_Exception
|
|
{
|
|
function __construct($previous=null)
|
|
{
|
|
return parent::__construct('Bad HTML in discovery data.', 0, $previous);
|
|
}
|
|
}
|
|
|
|
class oEmbedHelper_DiscoveryException extends oEmbedHelper_Exception
|
|
{
|
|
function __construct($previous=null)
|
|
{
|
|
return parent::__construct('No oEmbed discovery data.', 0, $previous);
|
|
}
|
|
}
|