Search moodle.org's
Developer Documentation

See Release Notes
Long Term Support Release

  • Bug fixes for general core bugs in 4.1.x will end 13 November 2023 (12 months).
  • Bug fixes for security issues in 4.1.x will end 10 November 2025 (36 months).
  • PHP version: minimum PHP 7.4.0 Note: minimum PHP version has increased since Moodle 4.0. PHP 8.0.x is supported too.
/blog/ -> rsslib.php (source)

Differences Between: [Versions 310 and 401] [Versions 39 and 401]

   1  <?php
   2  // This file is part of Moodle - http://moodle.org/
   3  //
   4  // Moodle is free software: you can redistribute it and/or modify
   5  // it under the terms of the GNU General Public License as published by
   6  // the Free Software Foundation, either version 3 of the License, or
   7  // (at your option) any later version.
   8  //
   9  // Moodle is distributed in the hope that it will be useful,
  10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  // GNU General Public License for more details.
  13  //
  14  // You should have received a copy of the GNU General Public License
  15  // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  16  
  17  /**
  18   * Blog RSS Management
  19   *
  20   * @package    core_blog
  21   * @category   rss
  22   * @copyright  2010 Andrew Davis
  23   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  24   */
  25  defined('MOODLE_INTERNAL') || die();
  26  
  27  require_once($CFG->dirroot.'/lib/rsslib.php');
  28  require_once($CFG->dirroot .'/blog/lib.php');
  29  
  30  /**
  31   * Build the URL for the RSS feed
  32   *
  33   * @param int    $contextid    The context under which the URL should be created
  34   * @param int    $userid       The id of the user requesting the RSS Feed
  35   * @param string $filtertype   The source of the RSS feed (site/course/group/user)
  36   * @param int    $filterselect The id of the item defined by $filtertype
  37   * @param int    $tagid        The id of the row in the tag table that identifies the RSS Feed
  38   * @return string
  39   */
  40  function blog_rss_get_url($contextid, $userid, $filtertype, $filterselect = 0, $tagid = 0) {
  41      $componentname = 'blog';
  42  
  43      $additionalargs = null;
  44      switch ($filtertype) {
  45          case 'site':
  46              $additionalargs = 'site/'.SITEID;
  47          break;
  48          case 'course':
  49              $additionalargs = 'course/'.$filterselect;
  50          break;
  51          case 'group':
  52              $additionalargs = 'group/'.$filterselect;
  53          break;
  54          case 'user':
  55              $additionalargs = 'user/'.$filterselect;
  56          break;
  57      }
  58  
  59      if ($tagid) {
  60          $additionalargs .= '/'.$tagid;
  61      }
  62  
  63      return rss_get_url($contextid, $userid, $componentname, $additionalargs);
  64  }
  65  
  66  /**
  67   * Print the link for the RSS feed with the correct RSS icon (Theme based)
  68   *
  69   * @param stdClass    $context      The context under which the URL should be created
  70   * @param string      $filtertype   The source of the RSS feed (site/course/group/user)
  71   * @param int         $filterselect The id of the item defined by $filtertype
  72   * @param int         $tagid        The id of the row in the tag table that identifies the RSS Feed
  73   * @param string      $tooltiptext  The tooltip to be displayed with the link
  74   */
  75  function blog_rss_print_link($context, $filtertype, $filterselect = 0, $tagid = 0, $tooltiptext = '') {
  76      global $CFG, $USER, $OUTPUT;
  77  
  78      if (!isloggedin()) {
  79          $userid = $CFG->siteguest;
  80      } else {
  81          $userid = $USER->id;
  82      }
  83  
  84      $url = blog_rss_get_url($context->id, $userid, $filtertype, $filterselect, $tagid);
  85      $rsspix = $OUTPUT->pix_icon('i/rss', get_string('rss'), 'core', array('title' => $tooltiptext));
  86      print '<div class="float-sm-right"><a href="'. $url .'">' . $rsspix . '</a></div>';
  87  }
  88  
  89  /**
  90   * Build the URL for the RSS feed amd add it as a header
  91   *
  92   * @param stdClass    $context      The context under which the URL should be created
  93   * @param string      $title        Name for the link to be added to the page header
  94   * @param string      $filtertype   The source of the RSS feed (site/course/group/user)
  95   * @param int         $filterselect The id of the item defined by $filtertype
  96   * @param int         $tagid        The id of the row in the tag table that identifies the RSS Feed
  97   */
  98  function blog_rss_add_http_header($context, $title, $filtertype, $filterselect = 0, $tagid = 0) {
  99      global $PAGE, $USER, $CFG;
 100  
 101      if (!isloggedin()) {
 102          $userid = $CFG->siteguest;
 103      } else {
 104          $userid = $USER->id;
 105      }
 106  
 107      $rsspath = blog_rss_get_url($context->id, $userid, $filtertype, $filterselect, $tagid);
 108      $PAGE->add_alternate_version($title, $rsspath, 'application/rss+xml');
 109  }
 110  
 111  /**
 112   * Utility function to extract parameters needed to generate RSS URLs from the blog filters
 113   *
 114   * @param  array $filters filters for the blog
 115   * @return array array containing the id of the user/course/group, the relevant context and the filter type: site/user/course/group
 116   */
 117  function blog_rss_get_params($filters) {
 118      $thingid = $rsscontext = $filtertype = null;
 119  
 120      $sitecontext = context_system::instance();
 121  
 122      if (!$filters) {
 123          $thingid = SITEID;
 124          $filtertype = 'site';
 125      } else if (array_key_exists('course', $filters)) {
 126          $thingid = $filters['course'];
 127          $filtertype = 'course';
 128      } else if (array_key_exists('user', $filters)) {
 129          $thingid = $filters['user'];
 130          $filtertype = 'user';
 131      } else if (array_key_exists('group', $filters)) {
 132          $thingid = $filters['group'];
 133          $filtertype = 'group';
 134      }
 135  
 136      return array($thingid, $rsscontext, $filtertype);
 137  }
 138  
 139  /**
 140   * Generate any blog RSS feed via one function
 141   *
 142   * @param stdClass $context The context of the blog for which the feed it being generated
 143   * @param array    $args    An array of arguements needed to build the feed (contextid, token, componentname, type, id, tagid)
 144   */
 145  function blog_rss_get_feed($context, $args) {
 146      global $CFG, $SITE, $DB;
 147  
 148      if (empty($CFG->enableblogs)) {
 149          debugging('Blogging disabled on this site, RSS feeds are not available');
 150          return null;
 151      }
 152  
 153      if (empty($CFG->enablerssfeeds)) {
 154          debugging('Sorry, RSS feeds are disabled on this site');
 155          return '';
 156      }
 157  
 158      if ($CFG->bloglevel == BLOG_SITE_LEVEL) {
 159          if (isguestuser()) {
 160              debugging(get_string('nopermissiontoshow', 'error'));
 161              return '';
 162          }
 163      }
 164  
 165      $sitecontext = context_system::instance();
 166      if (!has_capability('moodle/blog:view', $sitecontext)) {
 167          return null;
 168      }
 169  
 170      $type  = clean_param($args[3], PARAM_ALPHA);
 171      $id = clean_param($args[4], PARAM_INT);  // Could be groupid / courseid  / userid  depending on $type.
 172  
 173      $tagid = 0;
 174      if ($args[5] != 'rss.xml') {
 175          $tagid = clean_param($args[5], PARAM_INT);
 176      } else {
 177          $tagid = 0;
 178      }
 179  
 180      $filename = blog_rss_file_name($type, $id, $tagid);
 181  
 182      if (file_exists($filename)) {
 183          if (filemtime($filename) + 3600 > time()) {
 184              return $filename;   // It's already done so we return cached version.
 185          }
 186      }
 187  
 188      $courseid = $groupid = $userid = null;
 189      switch ($type) {
 190          case 'site':
 191              break;
 192          case 'course':
 193              $courseid = $id;
 194              break;
 195          case 'group':
 196              $groupid = $id;
 197              break;
 198          case 'user':
 199              $userid = $id;
 200              break;
 201      }
 202  
 203      // Get all the entries from the database.
 204      require_once($CFG->dirroot .'/blog/locallib.php');
 205      $blogheaders = blog_get_headers($courseid, $groupid, $userid, $tagid);
 206  
 207      $bloglisting = new blog_listing($blogheaders['filters']);
 208      $blogentries = $bloglisting->get_entries();
 209  
 210      // Now generate an array of RSS items.
 211      if ($blogentries) {
 212          $items = array();
 213          foreach ($blogentries as $blogentry) {
 214              $item = new stdClass();
 215              $item->author = fullname($DB->get_record('user', array('id' => $blogentry->userid))); // TODO: this is slow.
 216              $item->title = $blogentry->subject;
 217              $item->pubdate = $blogentry->lastmodified;
 218              $item->link = $CFG->wwwroot.'/blog/index.php?entryid='.$blogentry->id;
 219              $summary = file_rewrite_pluginfile_urls($blogentry->summary, 'pluginfile.php',
 220                  $sitecontext->id, 'blog', 'post', $blogentry->id);
 221              $item->description = format_text($summary, $blogentry->format);
 222              if ($blogtags = core_tag_tag::get_item_tags_array('core', 'post', $blogentry->id)) {
 223                  $item->tags = $blogtags;
 224                  $item->tagscheme = $CFG->wwwroot . '/tag';
 225              }
 226              $items[] = $item;
 227          }
 228          $articles = rss_add_items($items);   // Change structure to XML.
 229      } else {
 230          $articles = '';
 231      }
 232  
 233      // Get header and footer information.
 234  
 235      switch ($type) {
 236          case 'user':
 237              $userfieldsapi = \core_user\fields::for_name();
 238              $info = fullname($DB->get_record('user', array('id' => $id),
 239                      $userfieldsapi->get_sql('', false, '', '', false)->selects));
 240              break;
 241          case 'course':
 242              $info = $DB->get_field('course', 'fullname', array('id' => $id));
 243              $info = format_string($info, true, array('context' => context_course::instance($id)));
 244              break;
 245          case 'site':
 246              $info = format_string($SITE->fullname, true, array('context' => context_course::instance(SITEID)));
 247              break;
 248          case 'group':
 249              $group = groups_get_group($id);
 250              $info = $group->name; // TODO: $DB->get_field('groups', 'name', array('id' => $id)).
 251              break;
 252          default:
 253              $info = '';
 254              break;
 255      }
 256  
 257      if ($tagid) {
 258          $info .= ': '.$DB->get_field('tags', 'text', array('id' => $tagid));
 259      }
 260  
 261      $header = rss_standard_header(get_string($type.'blog', 'blog', $info),
 262                                    $CFG->wwwroot.'/blog/index.php',
 263                                    get_string('intro', 'blog'));
 264  
 265      $footer = rss_standard_footer();
 266  
 267      // Save the XML contents to file.
 268      $rssdata = $header.$articles.$footer;
 269      if (blog_rss_save_file($type, $id, $tagid, $rssdata)) {
 270          return $filename;
 271      } else {
 272          return false;   // Couldn't find it or make it.
 273      }
 274  }
 275  
 276  /**
 277   * Retrieve the location and file name of a cached RSS feed
 278   *
 279   * @param string $type  The source of the RSS feed (site/course/group/user)
 280   * @param int    $id    The id of the item defined by $type
 281   * @param int    $tagid The id of the row in the tag table that identifies the RSS Feed
 282   * @return string
 283   */
 284  function blog_rss_file_name($type, $id, $tagid = 0) {
 285      global $CFG;
 286  
 287      if ($tagid) {
 288          return "$CFG->cachedir/rss/blog/$type/$id/$tagid.xml";
 289      } else {
 290          return "$CFG->cachedir/rss/blog/$type/$id.xml";
 291      }
 292  }
 293  
 294  /**
 295   * This function saves to file the rss feed specified in the parameters
 296   *
 297   * @param string $type     The source of the RSS feed (site/course/group/user)
 298   * @param int    $id       The id of the item defined by $type
 299   * @param int    $tagid    The id of the row in the tag table that identifies the RSS Feed
 300   * @param string $contents The contents of the RSS Feed file
 301   * @return bool whether the save was successful or not
 302   */
 303  function blog_rss_save_file($type, $id, $tagid = 0, $contents = '') {
 304      global $CFG;
 305  
 306      $status = true;
 307  
 308      // Blog creates some additional dirs within the rss cache so make sure they all exist.
 309      make_cache_directory('rss/blog');
 310      make_cache_directory('rss/blog/'.$type);
 311  
 312      $filename = blog_rss_file_name($type, $id, $tagid);
 313      $expandfilename = false; // We are supplying a full file path.
 314      $status = rss_save_file('blog', $filename, $contents, $expandfilename);
 315  
 316      return $status;
 317  }
 318  
 319  /**
 320   * Delete the supplied user's cached blog post RSS feed.
 321   * Only user blogs are available by RSS.
 322   * This doesn't call rss_delete_file() as blog RSS caching uses it's own file structure.
 323   *
 324   * @param int $userid
 325   */
 326  function blog_rss_delete_file($userid) {
 327      $filename = blog_rss_file_name('user', $userid);
 328      if (file_exists($filename)) {
 329          unlink($filename);
 330      }
 331  }
 332