<?php /** * StatusNet, the distributed open-source microblogging tool * * Plugin to do linkbacks for notices containing links * * PHP version 5 * * LICENCE: 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/>. * * @category Plugin * @package StatusNet * @author Evan Prodromou <evan@status.net> * @copyright 2009 StatusNet, Inc. * @license http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0 * @link http://status.net/ */ if (!defined('STATUSNET')) { exit(1); } require_once('Auth/Yadis/Yadis.php'); define('LINKBACKPLUGIN_VERSION', '0.1'); /** * Plugin to do linkbacks for notices containing URLs * * After new notices are saved, we check their text for URLs. If there * are URLs, we test each URL to see if it supports any * * @category Plugin * @package StatusNet * @author Evan Prodromou <evan@status.net> * @license http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0 * @link http://status.net/ * * @see Event */ class LinkbackPlugin extends Plugin { var $notice = null; function __construct() { parent::__construct(); } function onHandleQueuedNotice($notice) { if ($notice->is_local == 1) { // Try to avoid actually mucking with the // notice content $c = $notice->content; $this->notice = $notice; // Ignoring results common_replace_urls_callback($c, array($this, 'linkbackUrl')); } return true; } function linkbackUrl($url) { common_log(LOG_DEBUG,"Attempting linkback for " . $url); $orig = $url; $url = htmlspecialchars_decode($orig); $scheme = parse_url($url, PHP_URL_SCHEME); if (!in_array($scheme, array('http', 'https'))) { return $orig; } // XXX: Do a HEAD first to save some time/bandwidth $fetcher = Auth_Yadis_Yadis::getHTTPFetcher(); $result = $fetcher->get($url, array('User-Agent: ' . $this->userAgent(), 'Accept: application/html+xml,text/html')); if (!in_array($result->status, array('200', '206'))) { return $orig; } $pb = null; $tb = null; if (array_key_exists('X-Pingback', $result->headers)) { $pb = $result->headers['X-Pingback']; } else if (preg_match('/<link rel="pingback" href="([^"]+)" ?\/?>/', $result->body, $match)) { $pb = $match[1]; } if (!empty($pb)) { $this->pingback($result->final_url, $pb); } else { $tb = $this->getTrackback($result->body, $result->final_url); if (!empty($tb)) { $this->trackback($result->final_url, $tb); } } return $orig; } function pingback($url, $endpoint) { $args = array($this->notice->uri, $url); if (!extension_loaded('xmlrpc')) { if (!dl('xmlrpc.so')) { common_log(LOG_ERR, "Can't pingback; xmlrpc extension not available."); return; } } $request = HTTPClient::start(); try { $response = $request->post($endpoint, array('Content-Type: text/xml'), xmlrpc_encode_request('pingback.ping', $args)); $response = xmlrpc_decode($response->getBody()); if (xmlrpc_is_fault($response)) { common_log(LOG_WARNING, "Pingback error for '$url' ($endpoint): ". "$response[faultString] ($response[faultCode])"); } else { common_log(LOG_INFO, "Pingback success for '$url' ($endpoint): ". "'$response'"); } } catch (HTTP_Request2_Exception $e) { common_log(LOG_WARNING, "Pingback request failed for '$url' ($endpoint)"); } } // Largely cadged from trackback_cls.php by // Ran Aroussi <ran@blogish.org>, GPL2 or any later version // http://phptrackback.sourceforge.net/ function getTrackback($text, $url) { if (preg_match_all('/(<rdf:RDF.*?<\/rdf:RDF>)/sm', $text, $match, PREG_SET_ORDER)) { for ($i = 0; $i < count($match); $i++) { if (preg_match('|dc:identifier="' . preg_quote($url) . '"|ms', $match[$i][1])) { $rdf_array[] = trim($match[$i][1]); } } // Loop through the RDFs array and extract trackback URIs $tb_array = array(); // <- holds list of trackback URIs if (!empty($rdf_array)) { for ($i = 0; $i < count($rdf_array); $i++) { if (preg_match('/trackback:ping="([^"]+)"/', $rdf_array[$i], $array)) { $tb_array[] = trim($array[1]); break; } } } // Return Trackbacks if (empty($tb_array)) { return null; } else { return $tb_array[0]; } } if (preg_match_all('/(<a[^>]*?rel=[\'"]trackback[\'"][^>]*?>)/', $text, $match)) { foreach ($match[1] as $atag) { if (preg_match('/href=[\'"]([^\'"]*?)[\'"]/', $atag, $url)) { return $url[1]; } } } return null; } function trackback($url, $endpoint) { $profile = $this->notice->getProfile(); $args = array('title' => sprintf(_('%1$s\'s status on %2$s'), $profile->nickname, common_exact_date($this->notice->created)), 'excerpt' => $this->notice->content, 'url' => $this->notice->uri, 'blog_name' => $profile->nickname); $fetcher = Auth_Yadis_Yadis::getHTTPFetcher(); $result = $fetcher->post($endpoint, http_build_query($args), array('User-Agent: ' . $this->userAgent())); if ($result->status != '200') { common_log(LOG_WARNING, "Trackback error for '$url' ($endpoint): ". "$result->body"); } else { common_log(LOG_INFO, "Trackback success for '$url' ($endpoint): ". "'$result->body'"); } } function userAgent() { return 'LinkbackPlugin/'.LINKBACKPLUGIN_VERSION . ' StatusNet/' . STATUSNET_VERSION; } function onPluginVersion(&$versions) { $versions[] = array('name' => 'Linkback', 'version' => LINKBACKPLUGIN_VERSION, 'author' => 'Evan Prodromou', 'homepage' => 'http://status.net/wiki/Plugin:Linkback', 'rawdescription' => _m('Notify blog authors when their posts have been linked in '. 'microblog notices using '. '<a href="http://www.hixie.ch/specs/pingback/pingback">Pingback</a> '. 'or <a href="http://www.movabletype.org/docs/mttrackback.html">Trackback</a> protocols.')); return true; } }