lib/rssaction.php

   1 <?php
   2 /**
   3  * Laconica, the distributed open-source microblogging tool
   4  *
   5  * Base class for RSS 1.0 feed actions
   6  *
   7  * PHP version 5
   8  *
   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.
  13  *
  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.
  18  *
  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/>.
  21  *
  22  * @category  Mail
  23  * @package   Laconica
  24  * @author    Evan Prodromou <evan@controlyourself.ca>
  25  * @author    Earle Martin <earle@downlode.org>
  26  * @copyright 2008-9 Control Yourself, Inc.
  27  * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
  28  * @link      http://laconi.ca/
  29  */
  30
  31 if (!defined('LACONICA')) { exit(1); }
  32
  33 define('DEFAULT_RSS_LIMIT', 48);
  34
  35 class Rss10Action extends Action
  36 {
  37     # This will contain the details of each feed item's author and be used to generate SIOC data.
  38
  39     var $creators = array();
  40     var $limit = DEFAULT_RSS_LIMIT;
  41     var $notices = null;
  42     var $tags_already_output = array();
  43
  44     /**
  45      * Constructor
  46      *
  47      * Just wraps the Action constructor.
  48      *
  49      * @param string  $output URI to output to, default = stdout
  50      * @param boolean $indent Whether to indent output, default true
  51      *
  52      * @see Action::__construct
  53      */
  54
  55     function __construct($output='php://output', $indent=true)
  56     {
  57         parent::__construct($output, $indent);
  58     }
  59
  60     /**
  61      * Do we need to write to the database?
  62      *
  63      * @return boolean true
  64      */
  65
  66     function isReadonly()
  67     {
  68         return true;
  69     }
  70
  71     /**
  72      * Read arguments and initialize members
  73      *
  74      * @param array $args Arguments from $_REQUEST
  75      * @return boolean success
  76      */
  77
  78     function prepare($args)
  79     {
  80         parent::prepare($args);
  81         $this->limit = (int) $this->trimmed('limit');
  82         if ($this->limit == 0) {
  83             $this->limit = DEFAULT_RSS_LIMIT;
  84         }
  85         return true;
  86     }
  87
  88     /**
  89      * Handle a request
  90      *
  91      * @param array $args Arguments from $_REQUEST
  92      *
  93      * @return void
  94      */
  95
  96     function handle($args)
  97     {
  98         // Parent handling, including cache check
  99         parent::handle($args);
 100         // Get the list of notices
 101         if (empty($this->tag)) {
 102             $this->notices = $this->getNotices($this->limit);
 103         } else {
 104             $this->notices = $this->getTaggedNotices($this->tag, $this->limit);
 105         }
 106         $this->showRss();
 107     }
 108
 109     /**
 110      * Get the notices to output in this stream
 111      *
 112      * @return array an array of Notice objects sorted in reverse chron
 113      */
 114
 115     function getNotices()
 116     {
 117         return array();
 118     }
 119
 120     /**
 121      * Get a description of the channel
 122      *
 123      * Returns an array with the following
 124      * @return array
 125      */
 126
 127     function getChannel()
 128     {
 129         return array('url' => '',
 130                      'title' => '',
 131                      'link' => '',
 132                      'description' => '');
 133     }
 134
 135     function getImage()
 136     {
 137         return null;
 138     }
 139
 140     function showRss()
 141     {
 142         $this->initRss();
 143         $this->showChannel();
 144         $this->showImage();
 145
 146         foreach ($this->notices as $n) {
 147             $this->showItem($n);
 148         }
 149
 150         $this->showCreators();
 151         $this->endRss();
 152     }
 153
 154     function showChannel()
 155     {
 156
 157         $channel = $this->getChannel();
 158         $image = $this->getImage();
 159
 160         $this->elementStart('channel', array('rdf:about' => $channel['url']));
 161         $this->element('title', null, $channel['title']);
 162         $this->element('link', null, $channel['link']);
 163         $this->element('description', null, $channel['description']);
 164         $this->element('cc:licence', array('rdf:resource' => common_config('license','url')));
 165
 166         if ($image) {
 167             $this->element('image', array('rdf:resource' => $image));
 168         }
 169
 170         $this->elementStart('items');
 171         $this->elementStart('rdf:Seq');
 172
 173         foreach ($this->notices as $notice) {
 174             $this->element('rdf:li', array('rdf:resource' => $notice->uri));
 175         }
 176
 177         $this->elementEnd('rdf:Seq');
 178         $this->elementEnd('items');
 179
 180         $this->elementEnd('channel');
 181     }
 182
 183     function showImage()
 184     {
 185         $image = $this->getImage();
 186         if ($image) {
 187             $channel = $this->getChannel();
 188             $this->elementStart('image', array('rdf:about' => $image));
 189             $this->element('title', null, $channel['title']);
 190             $this->element('link', null, $channel['link']);
 191             $this->element('url', null, $image);
 192             $this->elementEnd('image');
 193         }
 194     }
 195
 196     // XXX: Surely there should be a common function to do this?
 197     function extract_tags ($string)
 198     {
 199         $count = preg_match_all('/(?:^|\s)#([A-Za-z0-9_\-\.]{1,64})/', strtolower($string), $match);
 200         if (!count)
 201         {
 202             return array();
 203         }
 204
 205         $rv = array();
 206         foreach ($match[1] as $tag)
 207         {
 208             $rv[] = common_canonical_tag($tag);
 209         }
 210
 211         return array_unique($rv);
 212     }
 213
 214     function showItem($notice)
 215     {
 216         $profile = Profile::staticGet($notice->profile_id);
 217         $nurl = common_local_url('shownotice', array('notice' => $notice->id));
 218         $creator_uri = common_profile_uri($profile);
 219         $this->elementStart('item', array('rdf:about' => $notice->uri,
 220                             'rdf:type' => 'http://rdfs.org/sioc/types#MicroblogPost'));
 221         $title = $profile->nickname . ': ' . common_xml_safe_str(trim($notice->content));
 222         $this->element('title', null, $title);
 223         $this->element('link', null, $nurl);
 224         $this->element('description', null, $profile->nickname."'s status on ".common_exact_date($notice->created));
 225         if ($notice->rendered) {
 226             $this->element('content:encoded', null, common_xml_safe_str($notice->rendered));
 227         }
 228         $this->element('dc:date', null, common_date_w3dtf($notice->created));
 229         $this->element('dc:creator', null, ($profile->fullname) ? $profile->fullname : $profile->nickname);
 230         $this->element('foaf:maker', array('rdf:resource' => $creator_uri));
 231         $this->element('sioc:has_creator', array('rdf:resource' => $creator_uri.'#acct'));
 232         $this->element('laconica:postIcon', array('rdf:resource' => $profile->avatarUrl()));
 233         $this->element('cc:licence', array('rdf:resource' => common_config('license', 'url')));
 234         if ($notice->reply_to) {
 235             $replyurl = common_local_url('shownotice', array('notice' => $notice->reply_to));
 236             $this->element('sioc:reply_of', array('rdf:resource' => $replyurl));
 237         }
 238         if (!empty($notice->conversation)) {
 239             $conversationurl = common_local_url('conversation',
 240                                          array('id' => $notice->conversation));
 241             $this->element('sioc:has_discussion', array('rdf:resource' => $conversationurl));
 242         }
 243         $attachments = $notice->attachments();
 244         if($attachments){
 245             foreach($attachments as $attachment){
 246                 if ($attachment->isEnclosure()) {
 247                     // DO NOT move xmlns declaration to root element. Making it
 248                     // the default namespace here improves compatibility with
 249                     // real-world feed readers.
 250                     $attribs = array(
 251                         'rdf:resource' => $attachment->url,
 252                         'url' => $attachment->url,
 253                         'xmlns' => 'http://purl.oclc.org/net/rss_2.0/enc#'
 254                         );
 255                     if ($attachment->title) {
 256                         $attribs['dc:title'] = $attachment->title;
 257                     }
 258                     if ($attachment->modified) {
 259                         $attribs['dc:date'] = common_date_w3dtf($attachment->modified);
 260                     }
 261                     if ($attachment->size) {
 262                         $attribs['length'] = $attachment->size;
 263                     }
 264                     if ($attachment->mimetype) {
 265                         $attribs['type'] = $attachment->mimetype;
 266                     }
 267                     $this->element('enclosure', $attribs);
 268                 }
 269                 $this->element('sioc:links_to', array('rdf:resource'=>$attachment->url));
 270             }
 271         }
 272         $tags = $this->extract_tags($notice->content);
 273         if (!empty($tags)) {
 274             foreach ($tags as $tag)
 275             {
 276                 $tagpage = common_local_url('tag', array('tag' => $tag));
 277
 278                 if ( in_array($tag, $this->tags_already_output) ) {
 279                     $this->element('ctag:tagged', array('rdf:resource'=>$tagpage.'#concept'));
 280                     continue;
 281                 }
 282
 283                 $tagrss  = common_local_url('tagrss', array('tag' => $tag));
 284                 $this->elementStart('ctag:tagged');
 285                 $this->elementStart('ctag:Tag', array('rdf:about'=>$tagpage.'#concept', 'ctag:label'=>$tag));
 286                 $this->element('foaf:page', array('rdf:resource'=>$tagpage));
 287                 $this->element('rdfs:seeAlso', array('rdf:resource'=>$tagrss));
 288                 $this->elementEnd('ctag:Tag');
 289                 $this->elementEnd('ctag:tagged');
 290
 291                 $this->tags_already_output[] = $tag;
 292             }
 293         }
 294         $this->elementEnd('item');
 295         $this->creators[$creator_uri] = $profile;
 296     }
 297
 298     function showCreators()
 299     {
 300         foreach ($this->creators as $uri => $profile) {
 301             $id = $profile->id;
 302             $nickname = $profile->nickname;
 303             $this->elementStart('foaf:Agent', array('rdf:about' => $uri));
 304             $this->element('foaf:nick', null, $nickname);
 305             if ($profile->fullname) {
 306                 $this->element('foaf:name', null, $profile->fullname);
 307             }
 308             $this->element('foaf:holdsAccount', array('rdf:resource' => $uri.'#acct'));
 309             $avatar = $profile->avatarUrl();
 310             $this->element('foaf:depiction', array('rdf:resource' => $avatar));
 311             $this->elementEnd('foaf:Agent');
 312         }
 313     }
 314
 315     function initRss()
 316     {
 317         $channel = $this->getChannel();
 318         header('Content-Type: application/rdf+xml');
 319
 320         $this->startXml();
 321         $this->elementStart('rdf:RDF', array('xmlns:rdf' =>
 322                                               'http://www.w3.org/1999/02/22-rdf-syntax-ns#',
 323                                               'xmlns:dc' =>
 324                                               'http://purl.org/dc/elements/1.1/',
 325                                               'xmlns:cc' =>
 326                                               'http://creativecommons.org/ns#',
 327                                               'xmlns:content' =>
 328                                               'http://purl.org/rss/1.0/modules/content/',
 329                                               'xmlns:ctag' =>
 330                                               'http://commontag.org/ns#',
 331                                               'xmlns:foaf' =>
 332                                               'http://xmlns.com/foaf/0.1/',
 333                                               'xmlns:sioc' =>
 334                                               'http://rdfs.org/sioc/ns#',
 335                                               'xmlns:sioct' =>
 336                                               'http://rdfs.org/sioc/types#',
 337                                               'xmlns:rdfs' =>
 338                                               'http://www.w3.org/2000/01/rdf-schema#',
 339                                               'xmlns:laconica' =>
 340                                               'http://laconi.ca/ont/',
 341                                               'xmlns' => 'http://purl.org/rss/1.0/'));
 342         $this->elementStart('sioc:Site', array('rdf:about' => common_root_url()));
 343         $this->element('sioc:name', null, common_config('site', 'name'));
 344         $this->elementStart('sioc:space_of');
 345         $this->element('sioc:Container', array('rdf:about' =>
 346                                                $channel['url']));
 347         $this->elementEnd('sioc:space_of');
 348         $this->elementEnd('sioc:Site');
 349     }
 350
 351     function endRss()
 352     {
 353         $this->elementEnd('rdf:RDF');
 354     }
 355
 356     /**
 357      * When was this page last modified?
 358      *
 359      */
 360
 361     function lastModified()
 362     {
 363         if (empty($this->notices)) {
 364             return null;
 365         }
 366
 367         if (count($this->notices) == 0) {
 368             return null;
 369         }
 370
 371         // FIXME: doesn't handle modified profiles, avatars, deleted notices
 372
 373         return strtotime($this->notices[0]->created);
 374     }
 375 }
 376