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Differences Between: [Versions 310 and 311] [Versions 311 and 400] [Versions 311 and 401] [Versions 311 and 402] [Versions 311 and 403] [Versions 39 and 311]

   1  <?php
   2  
   3  // This file is part of Moodle - http://moodle.org/
   4  //
   5  // Moodle is free software: you can redistribute it and/or modify
   6  // it under the terms of the GNU General Public License as published by
   7  // the Free Software Foundation, either version 3 of the License, or
   8  // (at your option) any later version.
   9  //
  10  // Moodle is distributed in the hope that it will be useful,
  11  // but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  // GNU General Public License for more details.
  14  //
  15  // You should have received a copy of the GNU General Public License
  16  // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
  17  
  18  /**
  19   * This file contains all the common stuff to be used in RSS System
  20   *
  21   * @package    core_rss
  22   * @category   rss
  23   * @copyright  1999 onwards Martin Dougiamas  {@link http://moodle.com}
  24   * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  25   */
  26  
  27  defined('MOODLE_INTERNAL') || die();
  28  
  29  /**
  30   * Build the URL for the RSS feed and add it as a header
  31   *
  32   * @param stdClass    $context           The context under which the URL should be created
  33   * @param string      $componentname     The name of the component for which the RSS feed exists
  34   * @param stdClass    $componentinstance The instance of the component
  35   * @param string      $title             Name for the link to be added to the page header
  36   */
  37  function rss_add_http_header($context, $componentname, $componentinstance, $title) {
  38      global $PAGE, $USER;
  39  
  40      $componentid = null;
  41      if (is_object($componentinstance)) {
  42          $componentid = $componentinstance->id;
  43      } else {
  44          $componentid = $componentinstance;
  45      }
  46  
  47      $rsspath = rss_get_url($context->id, $USER->id, $componentname, $componentid);
  48      $PAGE->add_alternate_version($title, $rsspath, 'application/rss+xml');
  49   }
  50  
  51  /**
  52   * Print the link for the RSS feed with the correct RSS icon
  53   *
  54   * @param stdClass    $contextid     The id of the context under which the URL should be created
  55   * @param int         $userid        The source of the RSS feed (site/course/group/user)
  56   * @param string      $componentname The name of the component for which the feed exists
  57   * @param string      $id            The name by which to call the RSS File
  58   * @param string      $tooltiptext   The tooltip to be displayed with the link
  59   * @return string HTML output for the RSS link
  60   */
  61  function rss_get_link($contextid, $userid, $componentname, $id, $tooltiptext='') {
  62      global $OUTPUT;
  63  
  64      static $rsspath = '';
  65  
  66      $rsspath = rss_get_url($contextid, $userid, $componentname, $id);
  67  
  68      return '<a href="'. $rsspath .'">' . $OUTPUT->pix_icon('i/rss', $tooltiptext) . '</a>';
  69  }
  70  
  71  /**
  72   * This function returns the URL for the RSS XML file.
  73   *
  74   * @param int    $contextid      the course id
  75   * @param int    $userid         the current user id
  76   * @param string $componentname  the name of the current component. For example "forum"
  77   * @param string $additionalargs For modules, module instance id
  78   * @return string the url of the RSS feed
  79   */
  80  function rss_get_url($contextid, $userid, $componentname, $additionalargs) {
  81      global $CFG;
  82      if (empty($userid)) {
  83          $userid = guest_user()->id;
  84      }
  85      $usertoken = rss_get_token($userid);
  86      $url = '/rss/file.php';
  87      return moodle_url::make_file_url($url, '/'.$contextid.'/'.$usertoken.'/'.$componentname.'/'.$additionalargs.'/rss.xml');
  88  }
  89  
  90  /**
  91   * Print the link for the RSS feed with the correct RSS icon (Theme based)
  92   *
  93   * @param stdClass    $contextid     The id of the context under which the URL should be created
  94   * @param int         $userid        The source of the RSS feed (site/course/group/user)
  95   * @param string      $componentname The name of the component for which the feed exists
  96   * @param string      $id            The name by which to call the RSS File
  97   * @param string      $tooltiptext   The tooltip to be displayed with the link
  98   */
  99  function rss_print_link($contextid, $userid, $componentname, $id, $tooltiptext='') {
 100      print rss_get_link($contextid, $userid, $componentname, $id, $tooltiptext);
 101  
 102  }
 103  
 104  /**
 105   * Given an object, deletes all RSS files associated with it.
 106   *
 107   * @param string   $componentname the name of the module ie 'forum'. Used to construct the cache path.
 108   * @param stdClass $instance      An object with an id member variable ie $forum, $glossary.
 109   */
 110  function rss_delete_file($componentname, $instance) {
 111      global $CFG;
 112  
 113      $dirpath = "$CFG->cachedir/rss/$componentname";
 114      if (is_dir($dirpath)) {
 115          if (!$dh = opendir($dirpath)) {
 116              error_log("Directory permission error. RSS directory store for component '{$componentname}' exists but cannot be opened.", DEBUG_DEVELOPER);
 117              return;
 118          }
 119          while (false !== ($filename = readdir($dh))) {
 120              if ($filename!='.' && $filename!='..') {
 121                  if (preg_match("/{$instance->id}_/", $filename)) {
 122                      unlink("$dirpath/$filename");
 123                  }
 124              }
 125          }
 126      }
 127  }
 128  
 129  /**
 130   * Are RSS feeds enabled for the supplied module instance?
 131   *
 132   * @param string   $modname        The name of the module to be checked
 133   * @param stdClass $instance       An instance of an activity module ie $forum, $glossary.
 134   * @param bool     $hasrsstype     Should there be a rsstype member variable?
 135   * @param bool     $hasrssarticles Should there be a rssarticles member variable?
 136   * @return bool whether or not RSS is enabled for the module
 137   */
 138  function rss_enabled_for_mod($modname, $instance=null, $hasrsstype=true, $hasrssarticles=true) {
 139      if ($hasrsstype) {
 140          if (empty($instance->rsstype) || $instance->rsstype==0) {
 141              return false;
 142          }
 143      }
 144  
 145      //have they set the RSS feed to return 0 results?
 146      if ($hasrssarticles) {
 147          if (empty($instance->rssarticles) || $instance->rssarticles==0) {
 148              return false;
 149          }
 150      }
 151  
 152      if (!empty($instance) && !instance_is_visible($modname,$instance)) {
 153          return false;
 154      }
 155  
 156      return true;
 157  }
 158  
 159  /**
 160   * This function saves to file the rss feed specified in the parameters
 161   *
 162   * @param string $componentname  the module name ie forum. Used to create a cache directory.
 163   * @param string $filename       the name of the file to be created ie "rss.xml"
 164   * @param string $contents       the data to be written to the file
 165   * @param bool   $expandfilename whether or not the fullname of the RSS file should be used
 166   * @return bool whether the save was successful or not
 167   */
 168  function rss_save_file($componentname, $filename, $contents, $expandfilename=true) {
 169      global $CFG;
 170  
 171      $status = true;
 172  
 173      if (! $basedir = make_cache_directory ('rss/'. $componentname)) {
 174          //Cannot be created, so error
 175          $status = false;
 176      }
 177  
 178      if ($status) {
 179          $fullfilename = $filename;
 180          if ($expandfilename) {
 181              $fullfilename = rss_get_file_full_name($componentname, $filename);
 182          }
 183  
 184          $rss_file = fopen($fullfilename, "w");
 185          if ($rss_file) {
 186              $status = fwrite ($rss_file, $contents);
 187              fclose($rss_file);
 188          } else {
 189              $status = false;
 190          }
 191      }
 192      return $status;
 193  }
 194  
 195  /**
 196   * Retrieve the location and file name of a cached RSS feed
 197   *
 198   * @param string $componentname the name of the component the RSS feed is being created for
 199   * @param string $filename the name of the RSS FEED
 200   * @return string The full name and path of the RSS file
 201   */
 202  function rss_get_file_full_name($componentname, $filename) {
 203      global $CFG;
 204      return "$CFG->cachedir/rss/$componentname/$filename.xml";
 205  }
 206  
 207  /**
 208   * Construct the file name of the RSS File
 209   *
 210   * @param stdClass $instance the instance of the source of the RSS feed
 211   * @param string $sql the SQL used to produce the RSS feed
 212   * @param array $params the parameters used in the SQL query
 213   * @return string the name of the RSS file
 214   */
 215  function rss_get_file_name($instance, $sql, $params = array()) {
 216      if ($params) {
 217          // If a parameters array is passed, then we want to
 218          // serialize it and then concatenate it with the sql.
 219          // The reason for this is to generate a unique filename
 220          // for queries using the same sql but different parameters.
 221          asort($params);
 222          $serializearray = serialize($params);
 223          return $instance->id.'_'.md5($sql . $serializearray);
 224      } else {
 225          return $instance->id.'_'.md5($sql);
 226      }
 227  }
 228  
 229  /**
 230   * This function return all the common headers for every rss feed in the site
 231   *
 232   * @param string $title       the title for the RSS Feed
 233   * @param string $link        the link for the origin of the RSS feed
 234   * @param string $description the description of the contents of the RSS feed
 235   * @return bool|string the standard header for the RSS feed
 236   */
 237  function rss_standard_header($title = NULL, $link = NULL, $description = NULL) {
 238      global $CFG, $USER, $OUTPUT;
 239  
 240      $status = true;
 241      $result = "";
 242  
 243      $site = get_site();
 244  
 245      if ($status) {
 246  
 247          //Calculate title, link and description
 248          if (empty($title)) {
 249              $title = format_string($site->fullname);
 250          }
 251          if (empty($link)) {
 252              $link = $CFG->wwwroot;
 253          }
 254          if (empty($description)) {
 255              $description = $site->summary;
 256          }
 257  
 258          //xml headers
 259          $result .= "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n";
 260          $result .= "<rss version=\"2.0\">\n";
 261  
 262          //open the channel
 263          $result .= rss_start_tag('channel', 1, true);
 264  
 265          //write channel info
 266          $result .= rss_full_tag('title', 2, false, strip_tags($title));
 267          $result .= rss_full_tag('link', 2, false, $link);
 268          $result .= rss_full_tag('description', 2, false, $description);
 269          $result .= rss_full_tag('generator', 2, false, 'Moodle');
 270          if (!empty($USER->lang)) {
 271              $result .= rss_full_tag('language', 2, false, substr($USER->lang,0,2));
 272          }
 273          $today = getdate();
 274          $result .= rss_full_tag('copyright', 2, false, '(c) '. $today['year'] .' '. format_string($site->fullname));
 275          /*
 276         if (!empty($USER->email)) {
 277              $result .= rss_full_tag('managingEditor', 2, false, fullname($USER));
 278              $result .= rss_full_tag('webMaster', 2, false, fullname($USER));
 279          }
 280         */
 281  
 282          //write image info
 283          $rsspix = $OUTPUT->image_url('i/rsssitelogo');
 284  
 285          //write the info
 286          $result .= rss_start_tag('image', 2, true);
 287          $result .= rss_full_tag('url', 3, false, $rsspix);
 288          $result .= rss_full_tag('title', 3, false, 'moodle');
 289          $result .= rss_full_tag('link', 3, false, $CFG->wwwroot);
 290          $result .= rss_full_tag('width', 3, false, '140');
 291          $result .= rss_full_tag('height', 3, false, '35');
 292          $result .= rss_end_tag('image', 2, true);
 293      }
 294  
 295      if (!$status) {
 296          return false;
 297      } else {
 298          return $result;
 299      }
 300  }
 301  
 302  
 303  /**
 304   * Generates the rss XML code for every item passed in the array
 305   *
 306   * item->title: The title of the item
 307   * item->author: The author of the item. Optional !!
 308   * item->pubdate: The pubdate of the item
 309   * item->link: The link url of the item
 310   * item->description: The content of the item
 311   *
 312   * @param array $items an array of item objects
 313   * @return bool|string the rss XML code for every item passed in the array
 314   */
 315  function rss_add_items($items) {
 316      global $CFG;
 317  
 318      $result = '';
 319  
 320      if (!empty($items)) {
 321          foreach ($items as $item) {
 322              $result .= rss_start_tag('item',2,true);
 323              //Include the category if exists (some rss readers will use it to group items)
 324              if (isset($item->category)) {
 325                  $result .= rss_full_tag('category',3,false,$item->category);
 326              }
 327              if (isset($item->tags)) {
 328                  $attributes = array();
 329                  if (isset($item->tagscheme)) {
 330                      $attributes['domain'] = s($item->tagscheme);
 331                  }
 332                  foreach ($item->tags as $tag) {
 333                      $result .= rss_full_tag('category', 3, false, $tag, $attributes);
 334                  }
 335              }
 336              $result .= rss_full_tag('title',3,false,strip_tags($item->title));
 337              $result .= rss_full_tag('link',3,false,$item->link);
 338              $result .= rss_add_enclosures($item);
 339              $result .= rss_full_tag('pubDate',3,false,gmdate('D, d M Y H:i:s',$item->pubdate).' GMT');  # MDL-12563
 340              //Include the author if exists
 341              if (isset($item->author) && !empty($item->author)) {
 342                  //$result .= rss_full_tag('author',3,false,$item->author);
 343                  //We put it in the description instead because it's more important
 344                  //for moodle than most other feeds, and most rss software seems to ignore
 345                  //the author field ...
 346                  $item->description = get_string('byname','',$item->author).'. &nbsp;<p>'.$item->description.'</p>';
 347              }
 348              $result .= rss_full_tag('description',3,false,$item->description);
 349              $result .= rss_full_tag('guid',3,false,$item->link,array('isPermaLink' => 'true'));
 350              $result .= rss_end_tag('item',2,true);
 351  
 352          }
 353      } else {
 354          $result = false;
 355      }
 356      return $result;
 357  }
 358  
 359  /**
 360   * This function return all the common footers for every rss feed in the site.
 361   *
 362   * @return string
 363   */
 364  function rss_standard_footer() {
 365      $status = true;
 366      $result = '';
 367  
 368      $result .= rss_end_tag('channel', 1, true);
 369      $result .= '</rss>';
 370  
 371      return $result;
 372  }
 373  
 374  
 375  /**
 376   * This function return an error xml file (string) to be sent when a rss is required (file.php) and something goes wrong
 377   *
 378   * @param string $errortype Type of error to send, default is rsserror
 379   * @return stdClass returns a XML Feed with an error message in it
 380   */
 381  function rss_geterrorxmlfile($errortype = 'rsserror') {
 382      global $CFG;
 383  
 384      $return = '';
 385  
 386      //XML Header
 387      $return = rss_standard_header();
 388  
 389      //XML item
 390      if ($return) {
 391          $item = new stdClass();
 392          $item->title       = "RSS Error";
 393          $item->link        = $CFG->wwwroot;
 394          $item->pubdate     = time();
 395          $item->description = get_string($errortype);
 396          $return .= rss_add_items(array($item));
 397      }
 398  
 399      //XML Footer
 400      if ($return) {
 401          $return .= rss_standard_footer();
 402      }
 403  
 404      return $return;
 405  }
 406  
 407  /**
 408   * Get the ID of the user from a given RSS Token
 409   *
 410   * @param string $token the RSS token you would like to use to find the user id
 411   * @return int The user id
 412   */
 413  function rss_get_userid_from_token($token) {
 414      global $DB;
 415  
 416      $sql = 'SELECT u.id FROM {user} u
 417              JOIN {user_private_key} k ON u.id = k.userid
 418              WHERE u.deleted = 0 AND u.confirmed = 1
 419              AND u.suspended = 0 AND k.value = ?';
 420      return $DB->get_field_sql($sql, array($token), IGNORE_MISSING);
 421  }
 422  
 423  /**
 424   * Get the RSS Token from a given user id
 425   *
 426   * @param int $userid The user id
 427   * @return string the RSS token for the user
 428   */
 429  function rss_get_token($userid) {
 430      return get_user_key('rss', $userid);
 431  }
 432  
 433  /**
 434   * Removes the token for the given user from the DB
 435   * @param int $userid The user id for the token you wish to delete
 436   */
 437  function rss_delete_token($userid) {
 438      delete_user_key('rss', $userid);
 439  }
 440  
 441  /**
 442   * Return the xml start tag
 443   *
 444   * @param string $tag        the xml tag name
 445   * @param int    $level      the indentation level
 446   * @param bool   $endline    whether or not to start new tags on a new line
 447   * @param array  $attributes the attributes of the xml tag
 448   * @return string the xml start tag
 449   */
 450  function rss_start_tag($tag,$level=0,$endline=false,$attributes=null) {
 451      if ($endline) {
 452         $endchar = "\n";
 453      } else {
 454         $endchar = "";
 455      }
 456      $attrstring = '';
 457      if (!empty($attributes) && is_array($attributes)) {
 458          foreach ($attributes as $key => $value) {
 459              $attrstring .= " ".$key."=\"".$value."\"";
 460          }
 461      }
 462      return str_repeat(" ",$level*2)."<".$tag.$attrstring.">".$endchar;
 463  }
 464  
 465  /**
 466   * Return the xml end tag
 467   * @param string $tag        the xml tag name
 468   * @param int    $level      the indentation level
 469   * @param bool   $endline    whether or not to start new tags on a new line
 470   * @return string the xml end tag
 471   */
 472  function rss_end_tag($tag,$level=0,$endline=true) {
 473      if ($endline) {
 474         $endchar = "\n";
 475      } else {
 476         $endchar = "";
 477      }
 478      return str_repeat(" ",$level*2)."</".$tag.">".$endchar;
 479  }
 480  
 481  /**
 482   * Return the while xml element, including content
 483   *
 484   * @param string $tag        the xml tag name
 485   * @param int    $level      the indentation level
 486   * @param bool   $endline    whether or not to start new tags on a new line
 487   * @param string $content    the text to go inside the tag
 488   * @param array  $attributes the attributes of the xml tag
 489   * @return string the whole xml element
 490   */
 491  function rss_full_tag($tag, $level, $endline, $content, $attributes = null) {
 492      $st = rss_start_tag($tag,$level,$endline,$attributes);
 493      $co="";
 494      $co = preg_replace("/\r\n|\r/", "\n", htmlspecialchars($content));
 495      $et = rss_end_tag($tag,0,true);
 496  
 497      return $st.$co.$et;
 498  }
 499  
 500  /**
 501   * Adds RSS Media Enclosures for "podcasting" by including attachments that
 502   * are specified in the item->attachments field.
 503   *
 504   * @param stdClass $item representing an RSS item
 505   * @return string RSS enclosure tags
 506   */
 507  function rss_add_enclosures($item){
 508      global $CFG;
 509  
 510      $returnstring = '';
 511  
 512      // list of media file extensions and their respective mime types
 513      include_once($CFG->libdir.'/filelib.php');
 514      $mediafiletypes = get_mimetypes_array();
 515  
 516      // take into account attachments (e.g. from forum) - with these, we are able to know the file size
 517      if (isset($item->attachments) && is_array($item->attachments)) {
 518          foreach ($item->attachments as $attachment){
 519              $extension = strtolower(substr($attachment->url, strrpos($attachment->url, '.')+1));
 520              if (isset($mediafiletypes[$extension]['type'])) {
 521                  $type = $mediafiletypes[$extension]['type'];
 522              } else {
 523                  $type = 'document/unknown';
 524              }
 525              $returnstring .= "\n<enclosure url=\"$attachment->url\" length=\"$attachment->length\" type=\"$type\" />\n";
 526          }
 527      }
 528  
 529      return $returnstring;
 530  }