question/upgrade.php

   1 <?php // $Id$
   2 /**
   3  * This file contains dtabase upgrade code that is called from lib/db/upgrade.php,
   4  * and also check methods that can be used for pre-install checks via
   5  * admin/environment.php and lib/environmentlib.php.
   6  *
   7  * @copyright &copy; 2007 The Open University
   8  * @author T.J.Hunt@open.ac.uk
   9  * @license http://www.gnu.org/copyleft/gpl.html GNU Public License
  10  * @package questionbank
  11  */
  12
  13 /**
  14  * This test is becuase the RQP question type was included in core
  15  * up to and including Moodle 1.8, and was removed before Moodle 1.9.
  16  *
  17  * Therefore, we want to check whether any rqp questions exist in the database
  18  * before doing the upgrade. However, the check is not relevant if that
  19  * question type was never installed, or if the person has chosen to
  20  * manually reinstall the rqp question type from contrib.
  21  *
  22  * @param $result the result object that can be modified.
  23  * @return null if the test is irrelevant, or true or false depending on whether the test passes.
  24  */
  25 function question_check_no_rqp_questions($result) {
  26     global $CFG;
  27
  28     if (empty($CFG->qtype_rqp_version) || is_dir($CFG->dirroot . '/question/type/rqp')) {
  29         return null;
  30     } else {
  31         $result->setStatus(count_records('question', 'qtype', 'rqp') == 0);
  32     }
  33     return $result;
  34 }
  35
  36 function question_remove_rqp_qtype() {
  37     global $CFG;
  38
  39     $result = true;
  40
  41     // Only remove the question type if the code is gone.
  42     if (!is_dir($CFG->dirroot . '/question/type/rqp')) {
  43         $table = new XMLDBTable('question_rqp_states');
  44         $result = $result && drop_table($table);
  45
  46         $table = new XMLDBTable('question_rqp');
  47         $result = $result && drop_table($table);
  48
  49         $table = new XMLDBTable('question_rqp_types');
  50         $result = $result && drop_table($table);
  51
  52         $table = new XMLDBTable('question_rqp_servers');
  53         $result = $result && drop_table($table);
  54
  55         $result = $result && unset_config('qtype_rqp_version');
  56     }
  57
  58     return $result;
  59 }
  60
  61 function question_remove_rqp_qtype_config_string() {
  62     global $CFG;
  63
  64     $result = true;
  65
  66     // An earlier, buggy version of the previous function missed out the unset_config call.
  67     if (!empty($CFG->qtype_rqp_version) && !is_dir($CFG->dirroot . '/question/type/rqp')) {
  68         $result = $result && unset_config('qtype_rqp_version');
  69     }
  70
  71     return $result;
  72 }
  73
  74 /**
  75  * @param $result the result object that can be modified.
  76  * @return null if the test is irrelevant, or true or false depending on whether the test passes.
  77  */
  78 function question_random_check($result){
  79     global $CFG;
  80     if (!empty($CFG->running_installer) //no test on first installation, no questions to test yet
  81             || $CFG->version >= 2007081000){//no test after upgrade seperates question cats into contexts.
  82         return null;
  83     }
  84     if (!$toupdate = question_cwqpfs_to_update()){
  85         $result->setStatus(true);//pass test
  86     } else {
  87         //set the feedback string here and not in xml file since we need something
  88         //more complex than just a string picked from admin.php lang file
  89         $a = new object();
  90         $a->reporturl = "{$CFG->wwwroot}/{$CFG->admin}/report/question/";
  91         $lang = str_replace('_utf8', '', current_language());
  92         $a->docsurl = "{$CFG->docroot}/$lang/admin/report/question/index";
  93         $result->setFeedbackStr(array('questioncwqpfscheck', 'admin', $a));
  94         $result->setStatus(false);//fail test
  95     }
  96     return $result;
  97 }
  98 /*
  99  * Delete all 'random' questions that are not been used in a quiz.
 100  */
 101 function question_delete_unused_random(){
 102     global $CFG;
 103     $tofix = array();
 104     $result = true;
 105     //delete all 'random' questions that are not been used in a quiz.
 106     if ($qqis = get_records_sql("SELECT q.* FROM {$CFG->prefix}question q LEFT JOIN ".
 107                                     "{$CFG->prefix}quiz_question_instances qqi ".
 108                                     "ON q.id = qqi.question WHERE q.qtype='random' AND qqi.question IS NULL")){
 109         $qqilist = join(array_keys($qqis), ',');
 110         $result = $result && delete_records_select('question', "id IN ($qqilist)");
 111     }
 112     return $result;
 113 }
 114 function question_cwqpfs_to_update($categories = null){
 115     global $CFG;
 116
 117     $tofix = array();
 118     $result = true;
 119
 120     //any cats with questions picking from subcats?
 121     if (!$cwqpfs = get_records_sql_menu("SELECT DISTINCT qc.id, 1 ".
 122                                     "FROM {$CFG->prefix}question q, {$CFG->prefix}question_categories qc ".
 123                                     "WHERE q.qtype='random' AND qc.id = q.category AND ".
 124                                      sql_compare_text('q.questiontext'). " = '1'")){
 125         return array();
 126     } else {
 127         if ($categories === null){
 128             $categories = get_records('question_categories');
 129         }
 130         $categorychildparents = array();
 131         foreach ($categories as $id => $category){
 132             $categorychildparents[$category->course][$id] = $category->parent;
 133         }
 134         foreach ($categories as $id => $category){
 135             if (FALSE !== array_key_exists($category->parent, $categorychildparents[$category->course])){
 136                 //this is not a top level cat
 137                 continue;//go to next category
 138             } else{
 139                 $tofix += question_cwqpfs_check_children($id, $categories, $categorychildparents[$category->course], $cwqpfs);
 140             }
 141         }
 142     }
 143
 144     return $tofix;
 145 }
 146
 147 function question_cwqpfs_check_children($checkid, $categories, $categorychildparents, $cwqpfs){
 148     $tofix = array();
 149     if (array_key_exists($checkid, $cwqpfs)){//cwqpfs in this cat
 150         $getchildren = array();
 151         $getchildren[] = $checkid;
 152         //search down tree and find all children
 153         while ($nextid = array_shift($getchildren)){//repeat until $getchildren
 154                                                     //empty;
 155             $childids = array_keys($categorychildparents, $nextid);
 156             foreach ($childids as $childid){
 157                 if ($categories[$childid]->publish != $categories[$checkid]->publish){
 158                     $tofix[$childid] = $categories[$checkid]->publish;
 159                 }
 160             }
 161             $getchildren = array_merge($getchildren, $childids);
 162         }
 163     } else { // check children for cwqpfs
 164         $childrentocheck = array_keys($categorychildparents, $checkid);
 165         foreach ($childrentocheck as $childtocheck){
 166             $tofix += question_cwqpfs_check_children($childtocheck, $categories, $categorychildparents, $cwqpfs);
 167         }
 168     }
 169     return $tofix;
 170 }
 171
 172 function question_category_next_parent_in($contextid, $question_categories, $id, $already_seen = array()){
 173     // Recursively look for an ancestor category of the given category that
 174     // belongs to context $contextid. (In a lot of cases, the parent will be
 175     // the one.) If there is none, return 0, meaning the top level.
 176     $already_seen[] = $id;
 177
 178     $nextparent = $question_categories[$id]->parent;
 179     if ($nextparent == 0) {
 180         // Hit the top level, we are done.
 181         return 0;
 182     } else if (!array_key_exists($nextparent, $question_categories)) {
 183         // The category hierarchy must have been screwed up before, in that
 184         // we have run out of categories to search, but without reaching the
 185         // top level. Repair the situation by returning 0, meaning top level.
 186         notify(get_string('upgradeproblemunknowncategory', 'question', $question_categories[$id]));
 187         return 0;
 188     } else if (in_array($nextparent, $already_seen)) {
 189         // The category hierarchy must have been screwed up before, in that
 190         // we have just found a loop in the category 'tree'. That should,
 191         // of course, be impossible, but it did acutally happen in at least once.
 192         // Repair the situation by returning 0, meaning top level.
 193         notify(get_string('upgradeproblemcategoryloop', 'question', implode(', ', $already_seen)));
 194         return 0;
 195     } else if ($contextid == $question_categories[$nextparent]->contextid) {
 196         // Found a suitable category, we are done.
 197         return $nextparent;
 198     } else {
 199         // The immediate parent is not in the same context, so look further up.
 200         return question_category_next_parent_in($contextid, $question_categories, $nextparent, $already_seen);
 201     }
 202 }
 203
 204 /**
 205  * Check that either category parent is 0 or a category shared in the same context.
 206  * Fix any categories to point to grand or grand grand parent etc in the same context or 0.
 207  */
 208 function question_category_checking($question_categories){
 209     //make an array that is easier to search
 210     $newparents = array();
 211     foreach ($question_categories as $id => $category){
 212         $newparents[$id] = question_category_next_parent_in($category->contextid, $question_categories, $id);
 213     }
 214     foreach (array_keys($question_categories) as $id){
 215         $question_categories[$id]->parent = $newparents[$id];
 216     }
 217     return $question_categories;
 218 }
 219
 220 function question_upgrade_context_etc(){
 221     global $CFG;
 222     $result = true;
 223     $result = $result && question_delete_unused_random();
 224
 225     $question_categories = get_records('question_categories');
 226     if ($question_categories) {
 227         //prepare content for new db structure
 228         $tofix = question_cwqpfs_to_update($question_categories);
 229         foreach ($tofix as $catid => $publish){
 230             $question_categories[$catid]->publish = $publish;
 231         }
 232
 233         foreach ($question_categories as $id => $question_category){
 234             $course = $question_categories[$id]->course;
 235             unset($question_categories[$id]->course);
 236             if ($question_categories[$id]->publish){
 237                 $context = get_context_instance(CONTEXT_SYSTEM);
 238                 //new name with old course name in brackets
 239                 $coursename = get_field('course', 'shortname', 'id', $course);
 240                 $question_categories[$id]->name .= " ($coursename)";
 241             } else {
 242                 $context = get_context_instance(CONTEXT_COURSE, $course);
 243             }
 244             $question_categories[$id]->contextid = $context->id;
 245             unset($question_categories[$id]->publish);
 246         }
 247
 248         $question_categories = question_category_checking($question_categories);
 249     }
 250
 251 /// Define index course (not unique) to be dropped form question_categories
 252     $table = new XMLDBTable('question_categories');
 253     $index = new XMLDBIndex('course');
 254     $index->setAttributes(XMLDB_INDEX_NOTUNIQUE, array('course'));
 255
 256 /// Launch drop index course
 257     $result = $result && drop_index($table, $index);
 258
 259 /// Define field course to be dropped from question_categories
 260     $field = new XMLDBField('course');
 261
 262 /// Launch drop field course
 263     $result = $result && drop_field($table, $field);
 264
 265 /// Define field context to be added to question_categories
 266     $field = new XMLDBField('contextid');
 267     $field->setAttributes(XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, null, null, '0', 'name');
 268     $field->comment = 'context that this category is shared in';
 269
 270 /// Launch add field context
 271     $result = $result && add_field($table, $field);
 272
 273 /// Define index context (not unique) to be added to question_categories
 274     $index = new XMLDBIndex('contextid');
 275     $index->setAttributes(XMLDB_INDEX_NOTUNIQUE, array('contextid'));
 276     $index->comment = 'links to context table';
 277
 278 /// Launch add index context
 279     $result = $result && add_index($table, $index);
 280
 281     $field = new XMLDBField('publish');
 282
 283 /// Launch drop field publish
 284     $result = $result && drop_field($table, $field);
 285
 286
 287     /// update table contents with previously calculated new contents.
 288     if ($question_categories) {
 289         foreach ($question_categories as $question_category) {
 290             $question_category->name = addslashes($question_category->name);
 291             $question_category->info = addslashes($question_category->info);
 292             if (!$result = $result && update_record('question_categories', $question_category)){
 293                 notify(get_string('upgradeproblemcouldnotupdatecategory', 'question', $question_category));
 294             }
 295         }
 296     }
 297
 298 /// Define field timecreated to be added to question
 299     $table = new XMLDBTable('question');
 300     $field = new XMLDBField('timecreated');
 301     $field->setAttributes(XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, null, null, '0', 'hidden');
 302
 303 /// Launch add field timecreated
 304     $result = $result && add_field($table, $field);
 305
 306 /// Define field timemodified to be added to question
 307     $table = new XMLDBTable('question');
 308     $field = new XMLDBField('timemodified');
 309     $field->setAttributes(XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED, XMLDB_NOTNULL, null, null, null, '0', 'timecreated');
 310
 311 /// Launch add field timemodified
 312     $result = $result && add_field($table, $field);
 313
 314 /// Define field createdby to be added to question
 315     $table = new XMLDBTable('question');
 316     $field = new XMLDBField('createdby');
 317     $field->setAttributes(XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED, null, null, null, null, null, 'timemodified');
 318
 319 /// Launch add field createdby
 320     $result = $result && add_field($table, $field);
 321
 322 /// Define field modifiedby to be added to question
 323     $table = new XMLDBTable('question');
 324     $field = new XMLDBField('modifiedby');
 325     $field->setAttributes(XMLDB_TYPE_INTEGER, '10', XMLDB_UNSIGNED, null, null, null, null, null, 'createdby');
 326
 327 /// Launch add field modifiedby
 328     $result = $result && add_field($table, $field);
 329
 330 /// Define key createdby (foreign) to be added to question
 331     $table = new XMLDBTable('question');
 332     $key = new XMLDBKey('createdby');
 333     $key->setAttributes(XMLDB_KEY_FOREIGN, array('createdby'), 'user', array('id'));
 334
 335 /// Launch add key createdby
 336     $result = $result && add_key($table, $key);
 337
 338 /// Define key modifiedby (foreign) to be added to question
 339     $table = new XMLDBTable('question');
 340     $key = new XMLDBKey('modifiedby');
 341     $key->setAttributes(XMLDB_KEY_FOREIGN, array('modifiedby'), 'user', array('id'));
 342
 343 /// Launch add key modifiedby
 344     $result = $result && add_key($table, $key);
 345
 346     return $result;
 347 }
 348
 349 /**
 350  * In Moodle, all random questions should have question.parent set to be the same
 351  * as question.id. One effect of MDL-5482 is that this will not be true for questions that
 352  * were backed up then restored. The probably does not cause many problems, except occasionally,
 353  * if the bogus question.parent happens to point to a multianswer question type, or when you
 354  * try to do a subsequent backup. Anyway, these question.parent values should be fixed, and
 355  * that is what this update does.
 356  */
 357 function question_fix_random_question_parents() {
 358     global $CFG;
 359     return execute_sql('UPDATE ' . $CFG->prefix . 'question SET parent = id ' .
 360             "WHERE qtype = 'random' AND parent <> id");
 361 }
 362
 363 ?>