question/backuplib.php

   1 <?php //$Id$
   2 /**
   3  * Question bank backup code.
   4  *
   5  * @license http://www.gnu.org/copyleft/gpl.html GNU Public License
   6  * @package questionbank
   7  *//** */
   8
   9 //This is the "graphical" structure of the question database:
  10     //To see, put your terminal to 160cc
  11
  12     // The following holds student-independent information about the questions
  13     //
  14     //          question_categories
  15     //             (CL,pk->id)
  16     //                  |
  17     //                  |
  18     //                  |.......................................
  19     //                  |                                      .
  20     //                  |                                      .
  21     //                  |    -------question_datasets------    .
  22     //                  |    |  (CL,pk->id,fk->question,  |    .
  23     //                  |    |   fk->dataset_definition)  |    .
  24     //                  |    |                            |    .
  25     //                  |    |                            |    .
  26     //                  |    |                            |    .
  27     //                  |    |                    question_dataset_definitions
  28     //                  |    |                      (CL,pk->id,fk->category)
  29     //              question                                   |
  30     //        (CL,pk->id,fk->category,files)                   |
  31     //                  |                             question_dataset_items
  32     //                  |                          (CL,pk->id,fk->definition)
  33     //                  |                                                                                                           question_rqp_type
  34     //                  |                                                                                                            (SL,pk->id)
  35     //                  |                                                                                                                  |
  36     //             --------------------------------------------------------------------------------------------------------------          |
  37     //             |             |              |              |                       |                  |                     |        question_rqp
  38     //             |             |              |              |                       |                  |                     |--(CL,pk->id,fk->question)
  39     //             |             |              |              |             question_calculated          |                     |
  40     //      question_truefalse   |     question_multichoice    |          (CL,pl->id,fk->question)        |                     |
  41     // (CL,pk->id,fk->question)  |   (CL,pk->id,fk->question)  |                       .                  |                     |  question_randomsamatch
  42     //             .             |              .              |                       .                  |                     |--(CL,pk->id,fk->question)
  43     //             .    question_shortanswer    .      question_numerical              .         question_multianswer.          |
  44     //             .  (CL,pk->id,fk->question)  .  (CL,pk->id,fk->question)            .        (CL,pk->id,fk->question)        |
  45     //             .             .              .              .                       .                  .                     |       question_match
  46     //             .             .              .              .                       .                  .                     |--(CL,pk->id,fk->question)
  47     //             .             .              .              .                       .                  .                     |             .
  48     //             .             .              .              .                       .                  .                     |             .
  49     //             .             .              .              .                       .                  .                     |             .
  50     //             .             .              .              .                       .                  .                     |    question_match_sub
  51     //             ........................................................................................                     |--(CL,pk->id,fk->question)
  52     //                                                   .                                                                      |
  53     //                                                   .                                                                      |
  54     //                                                   .                                                                      |  question_numerical_units
  55     //                                             question_answers                                                             |--(CL,pk->id,fk->question)
  56     //                                         (CL,pk->id,fk->question)----------------------------------------------------------
  57     //
  58     //
  59     // The following holds the information about student interaction with the questions
  60     //
  61     //             question_sessions
  62     //      (UL,pk->id,fk->attempt,question)
  63     //                    .
  64     //                    .
  65     //             question_states
  66     //       (UL,pk->id,fk->attempt,question)
  67     //                |
  68     //           question_rqp_states
  69     //        (UL,pk->id,fk->stateid)
  70     //
  71     // Meaning: pk->primary key field of the table
  72     //          fk->foreign key to link with parent
  73     //          nt->nested field (recursive data)
  74     //          SL->site level info
  75     //          CL->course level info
  76     //          UL->user level info
  77     //          files->table may have files
  78     //
  79     //-----------------------------------------------------------
  80
  81     require_once("$CFG->libdir/questionlib.php");
  82
  83     function backup_question_categories($bf,$preferences) {
  84
  85         global $CFG;
  86
  87         $status = true;
  88
  89         //First, we get the used categories from backup_ids
  90         $categories = question_category_ids_by_backup ($preferences->backup_unique_code);
  91
  92         //If we've categories
  93         if ($categories) {
  94              //Write start tag
  95              $status = fwrite($bf,start_tag("QUESTION_CATEGORIES",2,true));
  96              //Iterate over each category
  97             foreach ($categories as $cat) {
  98                 //Start category
  99                 $status = fwrite ($bf,start_tag("QUESTION_CATEGORY",3,true));
 100                 //Get category data from question_categories
 101                 $category = get_record ("question_categories","id",$cat->old_id);
 102                 //Print category contents
 103                 fwrite($bf,full_tag("ID",4,false,$category->id));
 104                 fwrite($bf,full_tag("NAME",4,false,$category->name));
 105                 fwrite($bf,full_tag("INFO",4,false,$category->info));
 106                 fwrite($bf,full_tag("PUBLISH",4,false,$category->publish));
 107                 fwrite($bf,full_tag("STAMP",4,false,$category->stamp));
 108                 fwrite($bf,full_tag("PARENT",4,false,$category->parent));
 109                 fwrite($bf,full_tag("SORTORDER",4,false,$category->sortorder));
 110                 //Now, backup their questions
 111                 $status = backup_question($bf,$preferences,$category->id);
 112                 //End category
 113                 $status = fwrite ($bf,end_tag("QUESTION_CATEGORY",3,true));
 114             }
 115             //Write end tag
 116             $status = fwrite ($bf,end_tag("QUESTION_CATEGORIES",2,true));
 117         }
 118
 119         return $status;
 120     }
 121
 122     //This function backups all the questions in selected category and their
 123     //asociated data
 124     function backup_question($bf,$preferences,$category, $level = 4) {
 125
 126         global $CFG, $QTYPES;
 127
 128         $status = true;
 129
 130         // We'll fetch the questions sorted by parent so that questions with no parents
 131         // (these are the ones which could be parents themselves) are backed up first. This
 132         // is important for the recoding of the parent field during the restore process
 133         $questions = get_records("question","category",$category,"parent ASC, id");
 134         //If there are questions
 135         if ($questions) {
 136             //Write start tag
 137             $status = fwrite ($bf,start_tag("QUESTIONS",$level,true));
 138             $counter = 0;
 139             //Iterate over each question
 140             foreach ($questions as $question) {
 141                 //Start question
 142                 $status = fwrite ($bf,start_tag("QUESTION",$level + 1,true));
 143                 //Print question contents
 144                 fwrite ($bf,full_tag("ID",$level + 2,false,$question->id));
 145                 fwrite ($bf,full_tag("PARENT",$level + 2,false,$question->parent));
 146                 fwrite ($bf,full_tag("NAME",$level + 2,false,$question->name));
 147                 fwrite ($bf,full_tag("QUESTIONTEXT",$level + 2,false,$question->questiontext));
 148                 fwrite ($bf,full_tag("QUESTIONTEXTFORMAT",$level + 2,false,$question->questiontextformat));
 149                 fwrite ($bf,full_tag("IMAGE",$level + 2,false,$question->image));
 150                 fwrite ($bf,full_tag("GENERALFEEDBACK",$level + 2,false,$question->generalfeedback));
 151                 fwrite ($bf,full_tag("DEFAULTGRADE",$level + 2,false,$question->defaultgrade));
 152                 fwrite ($bf,full_tag("PENALTY",$level + 2,false,$question->penalty));
 153                 fwrite ($bf,full_tag("QTYPE",$level + 2,false,$question->qtype));
 154                 fwrite ($bf,full_tag("LENGTH",$level + 2,false,$question->length));
 155                 fwrite ($bf,full_tag("STAMP",$level + 2,false,$question->stamp));
 156                 fwrite ($bf,full_tag("VERSION",$level + 2,false,$question->version));
 157                 fwrite ($bf,full_tag("HIDDEN",$level + 2,false,$question->hidden));
 158                 // Backup question type specific data
 159                 $status = $QTYPES[$question->qtype]->backup($bf,$preferences,$question->id, $level + 2);
 160                 //End question
 161                 $status = fwrite ($bf,end_tag("QUESTION",$level + 1,true));
 162                 //Do some output
 163                 $counter++;
 164                 if ($counter % 10 == 0) {
 165                     echo ".";
 166                     if ($counter % 200 == 0) {
 167                         echo "<br />";
 168                     }
 169                     backup_flush(300);
 170                 }
 171             }
 172             //Write end tag
 173             $status = fwrite ($bf,end_tag("QUESTIONS",$level,true));
 174         }
 175         return $status;
 176     }
 177
 178     //This function backups the answers data in some question types
 179     //(truefalse, shortanswer,multichoice,numerical,calculated)
 180     function question_backup_answers($bf,$preferences,$question, $level = 6) {
 181
 182         global $CFG;
 183
 184         $status = true;
 185
 186         $answers = get_records("question_answers","question",$question,"id");
 187         //If there are answers
 188         if ($answers) {
 189             $status = fwrite ($bf,start_tag("ANSWERS",$level,true));
 190             //Iterate over each answer
 191             foreach ($answers as $answer) {
 192                 $status = fwrite ($bf,start_tag("ANSWER",$level + 1,true));
 193                 //Print answer contents
 194                 fwrite ($bf,full_tag("ID",$level + 2,false,$answer->id));
 195                 fwrite ($bf,full_tag("ANSWER_TEXT",$level + 2,false,$answer->answer));
 196                 fwrite ($bf,full_tag("FRACTION",$level + 2,false,$answer->fraction));
 197                 fwrite ($bf,full_tag("FEEDBACK",$level + 2,false,$answer->feedback));
 198                 $status = fwrite ($bf,end_tag("ANSWER",$level + 1,true));
 199             }
 200             $status = fwrite ($bf,end_tag("ANSWERS",$level,true));
 201         }
 202         return $status;
 203     }
 204
 205     //This function backups question_numerical_units from different question types
 206     function question_backup_numerical_units($bf,$preferences,$question,$level=7) {
 207
 208         global $CFG;
 209
 210         $status = true;
 211
 212         $numerical_units = get_records("question_numerical_units","question",$question,"id");
 213         //If there are numericals_units
 214         if ($numerical_units) {
 215             $status = fwrite ($bf,start_tag("NUMERICAL_UNITS",$level,true));
 216             //Iterate over each numerical_unit
 217             foreach ($numerical_units as $numerical_unit) {
 218                 $status = fwrite ($bf,start_tag("NUMERICAL_UNIT",$level+1,true));
 219                 //Print numerical_unit contents
 220                 fwrite ($bf,full_tag("MULTIPLIER",$level+2,false,$numerical_unit->multiplier));
 221                 fwrite ($bf,full_tag("UNIT",$level+2,false,$numerical_unit->unit));
 222                 //Now backup numerical_units
 223                 $status = fwrite ($bf,end_tag("NUMERICAL_UNIT",$level+1,true));
 224             }
 225             $status = fwrite ($bf,end_tag("NUMERICAL_UNITS",$level,true));
 226         }
 227
 228         return $status;
 229
 230     }
 231
 232     //This function backups dataset_definitions (via question_datasets) from different question types
 233     function question_backup_datasets($bf,$preferences,$question,$level=7) {
 234
 235         global $CFG;
 236
 237         $status = true;
 238
 239         //First, we get the used datasets for this question
 240         $question_datasets = get_records("question_datasets","question",$question,"id");
 241         //If there are question_datasets
 242         if ($question_datasets) {
 243             $status = $status &&fwrite ($bf,start_tag("DATASET_DEFINITIONS",$level,true));
 244             //Iterate over each question_dataset
 245             foreach ($question_datasets as $question_dataset) {
 246                 $def = NULL;
 247                 //Get dataset_definition
 248                 if ($def = get_record("question_dataset_definitions","id",$question_dataset->datasetdefinition)) {;
 249                     $status = $status &&fwrite ($bf,start_tag("DATASET_DEFINITION",$level+1,true));
 250                     //Print question_dataset contents
 251                     fwrite ($bf,full_tag("CATEGORY",$level+2,false,$def->category));
 252                     fwrite ($bf,full_tag("NAME",$level+2,false,$def->name));
 253                     fwrite ($bf,full_tag("TYPE",$level+2,false,$def->type));
 254                     fwrite ($bf,full_tag("OPTIONS",$level+2,false,$def->options));
 255                     fwrite ($bf,full_tag("ITEMCOUNT",$level+2,false,$def->itemcount));
 256                     //Now backup dataset_entries
 257                     $status = question_backup_dataset_items($bf,$preferences,$def->id,$level+2);
 258                     //End dataset definition
 259                     $status = $status &&fwrite ($bf,end_tag("DATASET_DEFINITION",$level+1,true));
 260                 }
 261             }
 262             $status = $status &&fwrite ($bf,end_tag("DATASET_DEFINITIONS",$level,true));
 263         }
 264
 265         return $status;
 266
 267     }
 268
 269     //This function backups datases_items from dataset_definitions
 270     function question_backup_dataset_items($bf,$preferences,$datasetdefinition,$level=9) {
 271
 272         global $CFG;
 273
 274         $status = true;
 275
 276         //First, we get the datasets_items for this dataset_definition
 277         $dataset_items = get_records("question_dataset_items","definition",$datasetdefinition,"id");
 278         //If there are dataset_items
 279         if ($dataset_items) {
 280             $status = $status &&fwrite ($bf,start_tag("DATASET_ITEMS",$level,true));
 281             //Iterate over each dataset_item
 282             foreach ($dataset_items as $dataset_item) {
 283                 $status = $status &&fwrite ($bf,start_tag("DATASET_ITEM",$level+1,true));
 284                 //Print question_dataset contents
 285                 fwrite ($bf,full_tag("NUMBER",$level+2,false,$dataset_item->itemnumber));
 286                 fwrite ($bf,full_tag("VALUE",$level+2,false,$dataset_item->value));
 287                 //End dataset definition
 288                 $status = $status &&fwrite ($bf,end_tag("DATASET_ITEM",$level+1,true));
 289             }
 290             $status = $status &&fwrite ($bf,end_tag("DATASET_ITEMS",$level,true));
 291         }
 292
 293         return $status;
 294
 295     }
 296
 297
 298     //Backup question_states contents (executed from backup_quiz_attempts)
 299     function backup_question_states ($bf,$preferences,$attempt, $level = 6) {
 300
 301         global $CFG;
 302
 303         $status = true;
 304
 305         $question_states = get_records("question_states","attempt",$attempt,"id");
 306         //If there are states
 307         if ($question_states) {
 308             //Write start tag
 309             $status = fwrite ($bf,start_tag("STATES",$level,true));
 310             //Iterate over each state
 311             foreach ($question_states as $state) {
 312                 //Start state
 313                 $status = fwrite ($bf,start_tag("STATE",$level + 1,true));
 314                 //Print state contents
 315                 fwrite ($bf,full_tag("ID",$level + 2,false,$state->id));
 316                 fwrite ($bf,full_tag("QUESTION",$level + 2,false,$state->question));
 317                 fwrite ($bf,full_tag("ORIGINALQUESTION",$level + 2,false,$state->originalquestion));
 318                 fwrite ($bf,full_tag("SEQ_NUMBER",$level + 2,false,$state->seq_number));
 319                 fwrite ($bf,full_tag("ANSWER",$level + 2,false,$state->answer));
 320                 fwrite ($bf,full_tag("TIMESTAMP",$level + 2,false,$state->timestamp));
 321                 fwrite ($bf,full_tag("EVENT",$level + 2,false,$state->event));
 322                 fwrite ($bf,full_tag("GRADE",$level + 2,false,$state->grade));
 323                 fwrite ($bf,full_tag("RAW_GRADE",$level + 2,false,$state->raw_grade));
 324                 fwrite ($bf,full_tag("PENALTY",$level + 2,false,$state->penalty));
 325                 // now back up question type specific state information
 326                 $status = backup_question_rqp_state ($bf,$preferences,$state->id, $level + 2);
 327                 //End state
 328                 $status = fwrite ($bf,end_tag("STATE",$level + 1,true));
 329             }
 330             //Write end tag
 331             $status = fwrite ($bf,end_tag("STATES",$level,true));
 332         }
 333     }
 334
 335     //Backup question_sessions contents (executed from backup_quiz_attempts)
 336     function backup_question_sessions ($bf,$preferences,$attempt, $level = 6) {
 337         global $CFG;
 338
 339         $status = true;
 340
 341         $question_sessions = get_records("question_sessions","attemptid",$attempt,"id");
 342         //If there are sessions
 343         if ($question_sessions) {
 344             //Write start tag (the funny name 'newest states' has historical reasons)
 345             $status = fwrite ($bf,start_tag("NEWEST_STATES",$level,true));
 346             //Iterate over each newest_state
 347             foreach ($question_sessions as $newest_state) {
 348                 //Start newest_state
 349                 $status = fwrite ($bf,start_tag("NEWEST_STATE",$level + 1,true));
 350                 //Print newest_state contents
 351                 fwrite ($bf,full_tag("ID",$level + 2,false,$newest_state->id));
 352                 fwrite ($bf,full_tag("QUESTIONID",$level + 2,false,$newest_state->questionid));
 353                 fwrite ($bf,full_tag("NEWEST",$level + 2,false,$newest_state->newest));
 354                 fwrite ($bf,full_tag("NEWGRADED",$level + 2,false,$newest_state->newgraded));
 355                 fwrite ($bf,full_tag("SUMPENALTY",$level + 2,false,$newest_state->sumpenalty));
 356                 fwrite ($bf,full_tag("MANUALCOMMENT",$level + 2,false,$newest_state->manualcomment));
 357                 //End newest_state
 358                 $status = fwrite ($bf,end_tag("NEWEST_STATE",$level + 1,true));
 359             }
 360             //Write end tag
 361             $status = fwrite ($bf,end_tag("NEWEST_STATES",$level,true));
 362         }
 363         return $status;
 364     }
 365
 366     //Backup question_rqp_state contents (executed from backup_question_states)
 367     function backup_question_rqp_state ($bf,$preferences,$state, $level = 8) {
 368
 369         global $CFG;
 370
 371         $status = true;
 372
 373         $rqp_state = get_record("question_rqp_states","stateid",$state);
 374         //If there is a state
 375         if ($rqp_state) {
 376             //Write start tag
 377             $status = fwrite ($bf,start_tag("RQP_STATE",$level,true));
 378             //Print state contents
 379             fwrite ($bf,full_tag("RESPONSES",$level + 1,false,$rqp_state->responses));
 380             fwrite ($bf,full_tag("PERSISTENT_DATA",$level + 1,false,$rqp_state->persistent_data));
 381             fwrite ($bf,full_tag("TEMPLATE_VARS",$level + 1,false,$rqp_state->template_vars));
 382             //Write end tag
 383             $status = fwrite ($bf,end_tag("RQP_STATE",$level,true));
 384         }
 385         return $status;
 386     }
 387
 388     //Returns an array of categories id
 389     function question_category_ids_by_backup ($backup_unique_code) {
 390
 391         global $CFG;
 392
 393         return get_records_sql ("SELECT a.old_id, a.backup_code
 394                                  FROM {$CFG->prefix}backup_ids a
 395                                  WHERE a.backup_code = '$backup_unique_code' AND
 396                                        a.table_name = 'question_categories'");
 397     }
 398
 399     function question_ids_by_backup ($backup_unique_code) {
 400
 401         global $CFG;
 402
 403         return get_records_sql ("SELECT q.id, q.category
 404                                  FROM {$CFG->prefix}backup_ids a,
 405                                       {$CFG->prefix}question q
 406                                  WHERE a.backup_code = '$backup_unique_code' AND
 407                                        q.category = a.old_id AND
 408                                        a.table_name = 'question_categories'");
 409     }
 410
 411     //Delete category ids from backup_ids table
 412     function delete_category_ids ($backup_unique_code) {
 413         global $CFG;
 414         $status = true;
 415         $status = execute_sql("DELETE FROM {$CFG->prefix}backup_ids
 416                                WHERE backup_code = '$backup_unique_code'",false);
 417         return $status;
 418     }
 419
 420 ?>