search/documents/forum_document.php

   1 <?php
   2 /**
   3 * Global Search Engine for Moodle
   4 * Michael Champanis (mchampan) [cynnical@gmail.com]
   5 * review 1.8+ : Valery Fremaux [valery.fremaux@club-internet.fr]
   6 * 2007/08/02
   7 *
   8 * document handling for forum activity module
   9 * This file contains the mapping between a forum post and it's indexable counterpart,
  10 *
  11 * Functions for iterating and retrieving the necessary records are now also included
  12 * in this file, rather than mod/forum/lib.php
  13 **/
  14 /* see wiki_document.php for descriptions */
  15
  16 require_once("$CFG->dirroot/search/documents/document.php");
  17 require_once("$CFG->dirroot/mod/forum/lib.php");
  18
  19 /*
  20 * a class for representing searchable information
  21 *
  22 **/
  23 class ForumSearchDocument extends SearchDocument {
  24
  25     /**
  26     * constructor
  27     *
  28     */
  29     public function __construct(&$post, $forum_id, $course_id, $itemtype, $context_id) {
  30         // generic information
  31         $doc->docid        = $post['id'];
  32         $doc->documenttype = SEARCH_TYPE_FORUM;
  33         $doc->itemtype     = $itemtype;
  34         $doc->contextid    = $context_id;
  35
  36         $doc->title        = $post['subject'];
  37         $doc->author       = $post['firstname']." ".$post['lastname'];
  38         $doc->contents     = $post['message'];
  39         $doc->date         = $post['created'];
  40         $doc->url          = forum_make_link($post['discussion'], $post['id']);
  41
  42         // module specific information
  43         $data->forum      = $forum_id;
  44         $data->discussion = $post['discussion'];
  45
  46         parent::__construct($doc, $data, $course_id, $post['groupid'], $post['userid'], PATH_FOR_SEARCH_TYPE_FORUM);
  47     } //constructor
  48 } //ForumSearchDocument
  49
  50 /**
  51 * constructs a valid link to a chat content
  52 * @param discussion_id the discussion
  53 * @param post_id the id of a single post
  54 * @return a well formed link to forum message display
  55 */
  56 function forum_make_link($discussion_id, $post_id) {
  57     global $CFG;
  58
  59     return $CFG->wwwroot.'/mod/forum/discuss.php?d='.$discussion_id.'#'.$post_id;
  60 } //forum_make_link
  61
  62 /**
  63 * search standard API
  64 *
  65 */
  66 function forum_iterator() {
  67     $forums = get_records('forum');
  68     return $forums;
  69 } //forum_iterator
  70
  71 /**
  72 * search standard API
  73 * @param forum a forum instance
  74 * @return an array of searchable documents
  75 */
  76 function forum_get_content_for_index(&$forum) {
  77
  78     $documents = array();
  79     if (!$forum) return $documents;
  80
  81     $posts = forum_get_discussions_fast($forum->id);
  82     if (!$posts) return $documents;
  83
  84     $coursemodule = get_field('modules', 'id', 'name', 'forum');
  85     $cm = get_record('course_modules', 'course', $forum->course, 'module', $coursemodule, 'instance', $forum->id);
  86     $context = get_context_instance(CONTEXT_MODULE, $cm->id);
  87
  88     foreach($posts as $aPost) {
  89         $aPost->itemtype = 'head';
  90         if ($aPost) {
  91             if (strlen($aPost->message) > 0) {
  92                 $documents[] = new ForumSearchDocument(get_object_vars($aPost), $forum->id, $forum->course, 'head', $context->id);
  93             }
  94             if ($children = forum_get_child_posts_fast($aPost->id, $forum->id)) {
  95                 foreach($children as $aChild) {
  96                     $aChild->itemtype = 'post';
  97                     if (strlen($aChild->message) > 0) {
  98                         $documents[] = new ForumSearchDocument(get_object_vars($child), $forum->id, $forum->course, 'post', $context->id);
  99                     }
 100                 }
 101             }
 102         }
 103     }
 104     return $documents;
 105 } //forum_get_content_for_index
 106
 107 /**
 108 * returns a single forum search document based on a forum entry id
 109 * @param id an id for a single information stub
 110 * @param itemtype the type of information
 111 */
 112 function forum_single_document($id, $itemtype) {
 113
 114     // both known item types are posts so get them the same way
 115     $post = get_record('forum_posts', 'id', $id);
 116     $discussion = get_record('forum_discussions', 'id', $post->discussion);
 117     $coursemodule = get_field('modules', 'id', 'name', 'forum');
 118     $cm = get_record('course_modules', 'course', $discussion->course, 'module', $coursemodule, 'instance', $discussion->forum);
 119     $context = get_context_instance(CONTEXT_MODULE, $cm->id);
 120     return new ForumSearchDocument(get_object_vars($post), $discussion->forum, $discussion->course, $itemtype, $context->id);
 121 } //forum_single_document
 122
 123 /**
 124 * dummy delete function that aggregates id with itemtype.
 125 * this was here for a reason, but I can't remember it at the moment.
 126 *
 127 */
 128 function forum_delete($info, $itemtype) {
 129     $object->id = $info;
 130     $object->itemtype = $itemtype;
 131     return $object;
 132 } //forum_delete
 133
 134 /**
 135 * returns the var names needed to build a sql query for addition/deletions
 136 *
 137 */
 138 function forum_db_names() {
 139     //[primary id], [table name], [time created field name], [time modified field name]
 140     return array(
 141         array('id', 'forum_posts', 'created', 'modified', 'head', 'parent = 0'),
 142         array('id', 'forum_posts', 'created', 'modified', 'post', 'parent != 0')
 143     );
 144 } //forum_db_names
 145
 146 /**
 147 * reworked faster version from /mod/forum/lib.php
 148 * @param forum_id a forum identifier
 149 * @return an array of posts
 150 */
 151 function forum_get_discussions_fast($forum_id) {
 152     global $CFG, $USER;
 153
 154     $timelimit='';
 155     if (!empty($CFG->forum_enabletimedposts)) {
 156         if (!((isadmin() and !empty($CFG->admineditalways)) || isteacher(get_field('forum', 'course', 'id', $forum_id)))) {
 157             $now = time();
 158             $timelimit = " AND ((d.timestart = 0 OR d.timestart <= '$now') AND (d.timeend = 0 OR d.timeend > '$now')";
 159             if (!empty($USER->id)) {
 160                 $timelimit .= " OR d.userid = '$USER->id'";
 161             }
 162             $timelimit .= ')';
 163         }
 164     }
 165
 166     $query = "
 167         SELECT
 168             p.id,
 169             p.subject,
 170             p.discussion,
 171             p.message,
 172             p.created,
 173             d.groupid,
 174             p.userid,
 175             u.firstname,
 176             u.lastname
 177         FROM
 178             {$CFG->prefix}forum_discussions d
 179         JOIN
 180             {$CFG->prefix}forum_posts p
 181         ON
 182             p.discussion = d.id
 183         JOIN
 184             {$CFG->prefix}user u
 185         ON
 186             p.userid = u.id
 187         WHERE
 188             d.forum = '{$forum_id}' AND
 189             p.parent = 0
 190             $timelimit
 191         ORDER BY
 192             d.timemodified DESC
 193     ";
 194     return get_records_sql($query);
 195 } //forum_get_discussions_fast
 196
 197 /**
 198 * reworked faster version from /mod/forum/lib.php
 199 * @param parent the id of the first post within the discussion
 200 * @param forum_id the forum identifier
 201 * @return an array of posts
 202 */
 203 function forum_get_child_posts_fast($parent, $forum_id) {
 204     global $CFG;
 205
 206     $query = "
 207         SELECT
 208             p.id,
 209             p.subject,
 210             p.discussion,
 211             p.message,
 212             p.created,
 213             {$forum_id} AS forum,
 214             p.userid,
 215             u.firstname,
 216             u.lastname
 217         FROM
 218             {$CFG->prefix}forum_posts p
 219         LEFT JOIN
 220             {$CFG->prefix}user u
 221         ON
 222             p.userid = u.id
 223         WHERE
 224             p.parent = '{$parent}'
 225         ORDER BY
 226             p.created ASC
 227     ";
 228     return get_records_sql($query);
 229 } //forum_get_child_posts_fast
 230
 231 /**
 232 * this function handles the access policy to contents indexed as searchable documents. If this
 233 * function does not exist, the search engine assumes access is allowed.
 234 * When this point is reached, we already know that :
 235 * - user is legitimate in the surrounding context
 236 * - user may be guest and guest access is allowed to the module
 237 * - the function may perform local checks within the module information logic
 238 * @param path the access path to the module script code
 239 * @param itemtype the information subclassing (usefull for complex modules, defaults to 'standard')
 240 * @param this_id the item id within the information class denoted by itemtype. In forums, this id
 241 * points out the individual post.
 242 * @param user the user record denoting the user who searches
 243 * @param group_id the current group used by the user when searching
 244 * @return true if access is allowed, false elsewhere
 245 */
 246 function forum_check_text_access($path, $itemtype, $this_id, $user, $group_id){
 247     global $CFG;
 248
 249     include_once("{$CFG->dirroot}/{$path}/lib.php");
 250
 251     // get the glossary object and all related stuff
 252     $post = get_record('forum_posts', 'id', $this_id);
 253     $dicussion = get_record('forum_discussion', 'id', $post->discussion);
 254     $course = get_record('course', 'id', $discussion->course);
 255     $context_module = get_record('context', 'id', $context_id);
 256     $cm = get_record('course_modules', 'id', $context_module->instanceid);
 257     if (!$cm->visible and !has_capability('moodle/course:viewhiddenactivities', $context_module)) return false;
 258
 259     // approval check : entries should be approved for being viewed, or belongs to the user
 260     if (!$post->mailed && !has_capability('mod/forum:viewhiddentimeposts')) return false;
 261
 262     // group check : entries should be in accessible groups
 263     $current_group = get_current_group($course->id);
 264     if ((groupmode($course, $cm)  == SEPARATEGROUPS) && ($group_id != $current_group) && !has_capability('mod/forum:viewdiscussionsfromallgroups')) return false;
 265
 266     return true;
 267 } //forum_check_text_access
 268
 269 ?>