3 * StatusNet, the distributed open-source microblogging tool
5 * Plugin to do linkbacks for notices containing links
9 * LICENCE: This program is free software: you can redistribute it and/or modify
10 * it under the terms of the GNU Affero General Public License as published by
11 * the Free Software Foundation, either version 3 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU Affero General Public License for more details.
19 * You should have received a copy of the GNU Affero General Public License
20 * along with this program. If not, see <http://www.gnu.org/licenses/>.
24 * @author Evan Prodromou <evan@status.net>
25 * @copyright 2009 StatusNet, Inc.
26 * @license http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
27 * @link http://status.net/
30 if (!defined('STATUSNET')) {
34 require_once('Auth/Yadis/Yadis.php');
36 define('LINKBACKPLUGIN_VERSION', '0.1');
39 * Plugin to do linkbacks for notices containing URLs
41 * After new notices are saved, we check their text for URLs. If there
42 * are URLs, we test each URL to see if it supports any
46 * @author Evan Prodromou <evan@status.net>
47 * @license http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
48 * @link http://status.net/
52 class LinkbackPlugin extends Plugin
56 function __construct()
58 parent::__construct();
61 function onHandleQueuedNotice($notice)
63 if ($notice->is_local == 1) {
64 // Try to avoid actually mucking with the
66 $c = $notice->content;
67 $this->notice = $notice;
69 common_replace_urls_callback($c,
70 array($this, 'linkbackUrl'));
72 if($notice->isRepeat()) {
73 $repeat = Notice::getByID($notice->repeat_of);
74 $this->linkbackUrl($repeat->getUrl());
75 } else if(!empty($notice->reply_to)) {
76 $parent = $notice->getParent();
77 $this->linkbackUrl($parent->getUrl());
83 function linkbackUrl($url)
85 common_log(LOG_DEBUG,"Attempting linkback for " . $url);
88 $url = htmlspecialchars_decode($orig);
89 $scheme = parse_url($url, PHP_URL_SCHEME);
90 if (!in_array($scheme, array('http', 'https'))) {
94 // XXX: Do a HEAD first to save some time/bandwidth
96 $fetcher = Auth_Yadis_Yadis::getHTTPFetcher();
98 $result = $fetcher->get($url,
99 array('User-Agent: ' . $this->userAgent(),
100 'Accept: application/html+xml,text/html'));
102 if (!in_array($result->status, array('200', '206'))) {
106 $pb = $this->getPingback($result);
108 $this->pingback($result->final_url, $pb);
109 // XXX: Should handle relative-URI resolution in these detections
112 $tb = $this->getTrackback($result);
114 $this->trackback($result->final_url, $tb);
121 function getPingback($result) {
122 if (array_key_exists('X-Pingback', $result->headers)) {
123 return $result->headers['X-Pingback'];
124 } else if(preg_match('/<(?:link|a)[ ]+href="([^"]+)"[ ]+rel="[^" ]* ?pingback ?[^" ]*"[ ]*\/?>/i', $result->body, $match)
125 || preg_match('/<(?:link|a)[ ]+rel="[^" ]* ?pingback ?[^" ]*"[ ]+href="([^"]+)"[ ]*\/?>/i', $result->body, $match)) {
130 function pingback($url, $endpoint)
132 $args = array($this->notice->getUrl(), $url);
134 if (!extension_loaded('xmlrpc')) {
135 if (!dl('xmlrpc.so')) {
136 common_log(LOG_ERR, "Can't pingback; xmlrpc extension not available.");
141 $request = HTTPClient::start();
143 $response = $request->post($endpoint,
144 array('Content-Type: text/xml'),
145 xmlrpc_encode_request('pingback.ping', $args));
146 $response = xmlrpc_decode($response->getBody());
147 if (xmlrpc_is_fault($response)) {
148 common_log(LOG_WARNING,
149 "Pingback error for '$url' ($endpoint): ".
150 "$response[faultString] ($response[faultCode])");
153 "Pingback success for '$url' ($endpoint): ".
156 } catch (HTTP_Request2_Exception $e) {
157 common_log(LOG_WARNING,
158 "Pingback request failed for '$url' ($endpoint)");
162 // Largely cadged from trackback_cls.php by
163 // Ran Aroussi <ran@blogish.org>, GPL2 or any later version
164 // http://phptrackback.sourceforge.net/
165 function getTrackback($result)
167 $text = $result->body;
168 $url = $result->final_url;
170 if (preg_match_all('/(<rdf:RDF.*?<\/rdf:RDF>)/sm', $text, $match, PREG_SET_ORDER)) {
171 for ($i = 0; $i < count($match); $i++) {
172 if (preg_match('|dc:identifier="' . preg_quote($url) . '"|ms', $match[$i][1])) {
173 $rdf_array[] = trim($match[$i][1]);
177 // Loop through the RDFs array and extract trackback URIs
179 $tb_array = array(); // <- holds list of trackback URIs
181 if (!empty($rdf_array)) {
183 for ($i = 0; $i < count($rdf_array); $i++) {
184 if (preg_match('/trackback:ping="([^"]+)"/', $rdf_array[$i], $array)) {
185 $tb_array[] = trim($array[1]);
193 if (empty($tb_array)) {
200 if (preg_match_all('/(<a[^>]*?rel=[\'"]trackback[\'"][^>]*?>)/', $text, $match)) {
201 foreach ($match[1] as $atag) {
202 if (preg_match('/href=[\'"]([^\'"]*?)[\'"]/', $atag, $url)) {
212 function trackback($url, $endpoint)
214 $profile = $this->notice->getProfile();
216 // TRANS: Trackback title.
217 // TRANS: %1$s is a profile nickname, %2$s is a timestamp.
218 $args = array('title' => sprintf(_m('%1$s\'s status on %2$s'),
220 common_exact_date($this->notice->created)),
221 'excerpt' => $this->notice->content,
222 'url' => $this->notice->getUrl(),
223 'blog_name' => $profile->nickname);
225 $fetcher = Auth_Yadis_Yadis::getHTTPFetcher();
227 $result = $fetcher->post($endpoint,
228 http_build_query($args),
229 array('User-Agent: ' . $this->userAgent()));
231 if ($result->status != '200') {
232 common_log(LOG_WARNING,
233 "Trackback error for '$url' ($endpoint): ".
237 "Trackback success for '$url' ($endpoint): ".
242 public function version()
244 return LINKBACKPLUGIN_VERSION;
247 function onPluginVersion(array &$versions)
249 $versions[] = array('name' => 'Linkback',
250 'version' => LINKBACKPLUGIN_VERSION,
251 'author' => 'Evan Prodromou',
252 'homepage' => 'http://status.net/wiki/Plugin:Linkback',
254 // TRANS: Plugin description.
255 _m('Notify blog authors when their posts have been linked in '.
256 'microblog notices using '.
257 '<a href="http://www.hixie.ch/specs/pingback/pingback">Pingback</a> '.
258 'or <a href="http://www.movabletype.org/docs/mttrackback.html">Trackback</a> protocols.'));