Search moodle.org's
Developer Documentation

See Release Notes

  • Bug fixes for general core bugs in 3.11.x will end 14 Nov 2022 (12 months plus 6 months extension).
  • Bug fixes for security issues in 3.11.x will end 13 Nov 2023 (18 months plus 12 months extension).
  • PHP version: minimum PHP 7.3.0 Note: minimum PHP version has increased since Moodle 3.10. PHP 7.4.x is supported too.
<?php

// This file is part of Moodle - http://moodle.org/
//
// Moodle is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Moodle 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 General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.

/**
 * This file adds support to rss feeds generation
 *
 * @package   mod_forum
 * @category rss
 * @copyright 2001 Eloy Lafuente (stronk7) http://contiento.com
 * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
 */

/* Include the core RSS lib */
require_once($CFG->libdir.'/rsslib.php');

/**
 * Returns the path to the cached rss feed contents. Creates/updates the cache if necessary.
 * @param stdClass $context the context
 * @param array    $args    the arguments received in the url
 * @return string the full path to the cached RSS feed directory. Null if there is a problem.
 */
function forum_rss_get_feed($context, $args) {
    global $CFG, $DB, $USER;

    $status = true;

    //are RSS feeds enabled?
    if (empty($CFG->forum_enablerssfeeds)) {
        debugging('DISABLED (module configuration)');
        return null;
    }

    $forumid  = clean_param($args[3], PARAM_INT);
    $cm = get_coursemodule_from_instance('forum', $forumid, 0, false, MUST_EXIST);
    $modcontext = context_module::instance($cm->id);

    //context id from db should match the submitted one
    if ($context->id != $modcontext->id || !has_capability('mod/forum:viewdiscussion', $modcontext)) {
        return null;
    }

    $forum = $DB->get_record('forum', array('id' => $forumid), '*', MUST_EXIST);
    if (!rss_enabled_for_mod('forum', $forum)) {
        return null;
    }

    //the sql that will retreive the data for the feed and be hashed to get the cache filename
    list($sql, $params) = forum_rss_get_sql($forum, $cm);

    // Hash the sql to get the cache file name.
    $filename = rss_get_file_name($forum, $sql, $params);
    $cachedfilepath = rss_get_file_full_name('mod_forum', $filename);

    //Is the cache out of date?
    $cachedfilelastmodified = 0;
    if (file_exists($cachedfilepath)) {
        $cachedfilelastmodified = filemtime($cachedfilepath);
    }
    // Used to determine if we need to generate a new RSS feed.
    $dontrecheckcutoff = time() - 60; // Sixty seconds ago.

    // If it hasn't been generated we need to create it.
    // Otherwise, if it has been > 60 seconds since we last updated, check for new items.
    if (($cachedfilelastmodified == 0) || (($dontrecheckcutoff > $cachedfilelastmodified) &&
        forum_rss_newstuff($forum, $cm, $cachedfilelastmodified))) {
        // Need to regenerate the cached version.
        $result = forum_rss_feed_contents($forum, $sql, $params, $modcontext);
        $status = rss_save_file('mod_forum', $filename, $result);
    }

    //return the path to the cached version
    return $cachedfilepath;
}

/**
 * Given a forum object, deletes all cached RSS files associated with it.
 *
 * @param stdClass $forum
 */
function forum_rss_delete_file($forum) {
    rss_delete_file('mod_forum', $forum);
}

///////////////////////////////////////////////////////
//Utility functions

/**
 * If there is new stuff in the forum since $time this returns true
 * Otherwise it returns false.
 *
 * @param stdClass $forum the forum object
 * @param stdClass $cm    Course Module object
 * @param int      $time  check for items since this epoch timestamp
 * @return bool True for new items
 */
function forum_rss_newstuff($forum, $cm, $time) {
    global $DB;

    list($sql, $params) = forum_rss_get_sql($forum, $cm, $time);

    return $DB->record_exists_sql($sql, $params);
}

/**
 * Determines which type of SQL query is required, one for posts or one for discussions, and returns the appropriate query
 *
 * @param stdClass $forum the forum object
 * @param stdClass $cm    Course Module object
 * @param int      $time  check for items since this epoch timestamp
 * @return string the SQL query to be used to get the Discussion/Post details from the forum table of the database
 */
function forum_rss_get_sql($forum, $cm, $time=0) {
    if ($forum->rsstype == 1) { // Discussion RSS
        return forum_rss_feed_discussions_sql($forum, $cm, $time);
    } else { // Post RSS
        return forum_rss_feed_posts_sql($forum, $cm, $time);
    }
}

/**
 * Generates the SQL query used to get the Discussion details from the forum table of the database
 *
 * @param stdClass $forum     the forum object
 * @param stdClass $cm        Course Module object
 * @param int      $newsince  check for items since this epoch timestamp
 * @return string the SQL query to be used to get the Discussion details from the forum table of the database
 */
function forum_rss_feed_discussions_sql($forum, $cm, $newsince=0) {
    global $CFG, $DB, $USER;

    $timelimit = '';

    $modcontext = null;

    $now = floor(time() / 60) * 60; // DB Cache Friendly.
    $params = array();

    $modcontext = context_module::instance($cm->id);

    if (!empty($CFG->forum_enabletimedposts)) { /// Users must fulfill timed posts
        if (!has_capability('mod/forum:viewhiddentimedposts', $modcontext)) {
            $timelimit = " AND ((d.timestart <= :now1 AND (d.timeend = 0 OR d.timeend > :now2))";
            $params['now1'] = $now;
            $params['now2'] = $now;
            if (isloggedin()) {
                $timelimit .= " OR d.userid = :userid";
                $params['userid'] = $USER->id;
            }
            $timelimit .= ")";
        }
    }

    // Do we only want new posts?
    if ($newsince) {
        $params['newsince'] = $newsince;
        $newsince = " AND p.modified > :newsince";
    } else {
        $newsince = '';
    }

    // Get group enforcing SQL.
    $groupmode = groups_get_activity_groupmode($cm);
    $currentgroup = groups_get_activity_group($cm);
    list($groupselect, $groupparams) = forum_rss_get_group_sql($cm, $groupmode, $currentgroup, $modcontext);

    // Add the groupparams to the params array.
    $params = array_merge($params, $groupparams);

    $forumsort = "d.timemodified DESC";
    $postdata = "p.id AS postid, p.subject, p.created as postcreated, p.modified, p.discussion, p.userid, p.message as postmessage, p.messageformat AS postformat, p.messagetrust AS posttrust";
< $userpicturefields = user_picture::fields('u', null, 'userid');
> $userfieldsapi = \core_user\fields::for_userpic(); > $userpicturefields = $userfieldsapi->get_sql('u', false, '', 'userid', false)->selects;
$sql = "SELECT $postdata, d.id as discussionid, d.name as discussionname, d.timemodified, d.usermodified, d.groupid, d.timestart, d.timeend, $userpicturefields FROM {forum_discussions} d JOIN {forum_posts} p ON p.discussion = d.id JOIN {user} u ON p.userid = u.id WHERE d.forum = {$forum->id} AND p.parent = 0 AND p.deleted <> 1 $timelimit $groupselect $newsince ORDER BY $forumsort"; return array($sql, $params); } /** * Generates the SQL query used to get the Post details from the forum table of the database * * @param stdClass $forum the forum object * @param stdClass $cm Course Module object * @param int $newsince check for items since this epoch timestamp * @return string the SQL query to be used to get the Post details from the forum table of the database */ function forum_rss_feed_posts_sql($forum, $cm, $newsince=0) { global $USER; $modcontext = context_module::instance($cm->id); // Get group enforcement SQL. $groupmode = groups_get_activity_groupmode($cm); $currentgroup = groups_get_activity_group($cm); $params = array(); list($groupselect, $groupparams) = forum_rss_get_group_sql($cm, $groupmode, $currentgroup, $modcontext); // Add the groupparams to the params array. $params = array_merge($params, $groupparams); // Do we only want new posts? if ($newsince) { $params['newsince'] = $newsince; $newsince = " AND p.modified > :newsince"; } else { $newsince = ''; } $canseeprivatereplies = has_capability('mod/forum:readprivatereplies', $modcontext); if (!$canseeprivatereplies) { $privatewhere = ' AND (p.privatereplyto = :currentuser1 OR p.userid = :currentuser2 OR p.privatereplyto = 0)'; $params['currentuser1'] = $USER->id; $params['currentuser2'] = $USER->id; } else { $privatewhere = ''; }
< $usernamefields = get_all_user_name_fields(true, 'u');
> $userfieldsapi = \core_user\fields::for_name(); > $usernamefields = $userfieldsapi->get_sql('u', false, '', '', false)->selects;
$sql = "SELECT p.id AS postid, d.id AS discussionid, d.name AS discussionname, d.groupid, d.timestart, d.timeend, u.id AS userid, $usernamefields, p.subject AS postsubject, p.message AS postmessage, p.created AS postcreated, p.messageformat AS postformat, p.messagetrust AS posttrust, p.parent as postparent FROM {forum_discussions} d, {forum_posts} p, {user} u WHERE d.forum = {$forum->id} AND p.discussion = d.id AND p.deleted <> 1 AND u.id = p.userid $newsince $privatewhere $groupselect ORDER BY p.created desc"; return array($sql, $params); } /** * Retrieve the correct SQL snippet for group-only forums * * @param stdClass $cm Course Module object * @param int $groupmode the mode in which the forum's groups are operating * @param bool $currentgroup true if the user is from the a group enabled on the forum * @param stdClass $modcontext The context instance of the forum module * @return string SQL Query for group details of the forum */ function forum_rss_get_group_sql($cm, $groupmode, $currentgroup, $modcontext=null) { $groupselect = ''; $params = array(); if ($groupmode) { if ($groupmode == VISIBLEGROUPS or has_capability('moodle/site:accessallgroups', $modcontext)) { if ($currentgroup) { $groupselect = "AND (d.groupid = :groupid OR d.groupid = -1)"; $params['groupid'] = $currentgroup; } } else { // Separate groups without access all. if ($currentgroup) { $groupselect = "AND (d.groupid = :groupid OR d.groupid = -1)"; $params['groupid'] = $currentgroup; } else { $groupselect = "AND d.groupid = -1"; } } } return array($groupselect, $params); } /** * This function return the XML rss contents about the forum * It returns false if something is wrong * * @param stdClass $forum the forum object * @param string $sql the SQL used to retrieve the contents from the database * @param array $params the SQL parameters used * @param object $context the context this forum relates to * @return bool|string false if the contents is empty, otherwise the contents of the feed is returned * * @Todo MDL-31129 implement post attachment handling */ function forum_rss_feed_contents($forum, $sql, $params, $context) { global $CFG, $DB, $USER; $status = true; $recs = $DB->get_recordset_sql($sql, $params, 0, $forum->rssarticles); //set a flag. Are we displaying discussions or posts? $isdiscussion = true; if (!empty($forum->rsstype) && $forum->rsstype!=1) { $isdiscussion = false; } if (!$cm = get_coursemodule_from_instance('forum', $forum->id, $forum->course)) { print_error('invalidcoursemodule'); } $formatoptions = new stdClass(); $items = array(); foreach ($recs as $rec) { $item = new stdClass(); $discussion = new stdClass(); $discussion->id = $rec->discussionid; $discussion->groupid = $rec->groupid; $discussion->timestart = $rec->timestart; $discussion->timeend = $rec->timeend; $post = null; if (!$isdiscussion) { $post = new stdClass(); $post->id = $rec->postid; $post->parent = $rec->postparent; $post->userid = $rec->userid; } if ($isdiscussion && !forum_user_can_see_discussion($forum, $discussion, $context)) { // This is a discussion which the user has no permission to view $item->title = get_string('forumsubjecthidden', 'forum'); $message = get_string('forumbodyhidden', 'forum'); $item->author = get_string('forumauthorhidden', 'forum'); } else if (!$isdiscussion && !forum_user_can_see_post($forum, $discussion, $post, $USER, $cm)) { if (forum_user_can_see_post($forum, $discussion, $post, $USER, $cm, false)) { // This is a post which the user has no permission to view. $item->title = get_string('forumsubjecthidden', 'forum'); $message = get_string('forumbodyhidden', 'forum'); $item->author = get_string('forumauthorhidden', 'forum'); } else { // This is a post which has been deleted. $item->title = get_string('privacy:request:delete:post:subject', 'mod_forum'); $message = get_string('privacy:request:delete:post:subject', 'mod_forum'); $item->author = get_string('forumauthorhidden', 'forum'); } } else { // The user must have permission to view if ($isdiscussion && !empty($rec->discussionname)) { $item->title = format_string($rec->discussionname); } else if (!empty($rec->postsubject)) { $item->title = format_string($rec->postsubject); } else { //we should have an item title by now but if we dont somehow then substitute something somewhat meaningful $item->title = format_string($forum->name.' '.userdate($rec->postcreated,get_string('strftimedatetimeshort', 'langconfig'))); } $item->author = fullname($rec); $message = file_rewrite_pluginfile_urls($rec->postmessage, 'pluginfile.php', $context->id, 'mod_forum', 'post', $rec->postid); $formatoptions->trusted = $rec->posttrust; } if ($isdiscussion) { $item->link = $CFG->wwwroot."/mod/forum/discuss.php?d=".$rec->discussionid; } else { $item->link = $CFG->wwwroot."/mod/forum/discuss.php?d=".$rec->discussionid."&parent=".$rec->postid; } $formatoptions->trusted = $rec->posttrust; $item->description = format_text($message, $rec->postformat, $formatoptions, $forum->course); //TODO: MDL-31129 implement post attachment handling /*if (!$isdiscussion) { $post_file_area_name = str_replace('//', '/', "$forum->course/$CFG->moddata/forum/$forum->id/$rec->postid"); $post_files = get_directory_list("$CFG->dataroot/$post_file_area_name"); if (!empty($post_files)) { $item->attachments = array(); } }*/ $item->pubdate = $rec->postcreated; $items[] = $item; } $recs->close(); // Create the RSS header. $header = rss_standard_header(strip_tags(format_string($forum->name,true)), $CFG->wwwroot."/mod/forum/view.php?f=".$forum->id, format_string($forum->intro,true)); // TODO: fix format // Now all the RSS items, if there are any. $articles = ''; if (!empty($items)) { $articles = rss_add_items($items); } // Create the RSS footer. $footer = rss_standard_footer(); return $header . $articles . $footer; }