/**
* Create a question_attempt_step from records loaded from the database.
*
* For internal use only.
*
* @param Iterator $records Raw records loaded from the database.
* @param int $questionattemptid The id of the question_attempt to extract.
* @return question_attempt The newly constructed question_attempt.
*/
public static function load_from_records($records, $questionattemptid, question_usage_observer $observer, $preferredbehaviour)
{
$record = $records->current();
while ($record->questionattemptid != $questionattemptid) {
$record = $records->next();
if (!$records->valid()) {
throw new coding_exception("Question attempt {$questionattemptid} not found in the database.");
}
$record = $records->current();
}
try {
$question = question_bank::load_question($record->questionid);
} catch (Exception $e) {
// The question must have been deleted somehow. Create a missing
// question to use in its place.
$question = question_bank::get_qtype('missingtype')->make_deleted_instance($record->questionid, $record->maxmark + 0);
}
$qa = new question_attempt($question, $record->questionusageid, null, $record->maxmark + 0);
$qa->set_database_id($record->questionattemptid);
$qa->set_slot($record->slot);
$qa->variant = $record->variant + 0;
$qa->minfraction = $record->minfraction + 0;
$qa->maxfraction = $record->maxfraction + 0;
$qa->set_flagged($record->flagged);
$qa->questionsummary = $record->questionsummary;
$qa->rightanswer = $record->rightanswer;
$qa->responsesummary = $record->responsesummary;
$qa->timemodified = $record->timemodified;
$qa->behaviour = question_engine::make_behaviour($record->behaviour, $qa, $preferredbehaviour);
$qa->observer = $observer;
// If attemptstepid is null (which should not happen, but has happened
// due to corrupt data, see MDL-34251) then the current pointer in $records
// will not be advanced in the while loop below, and we get stuck in an
// infinite loop, since this method is supposed to always consume at
// least one record. Therefore, in this case, advance the record here.
if (is_null($record->attemptstepid)) {
$records->next();
}
$i = 0;
$autosavedstep = null;
$autosavedsequencenumber = null;
while ($record && $record->questionattemptid == $questionattemptid && !is_null($record->attemptstepid)) {
$sequencenumber = $record->sequencenumber;
$nextstep = question_attempt_step::load_from_records($records, $record->attemptstepid, $qa->get_question()->get_type_name());
if ($sequencenumber < 0) {
if (!$autosavedstep) {
$autosavedstep = $nextstep;
$autosavedsequencenumber = -$sequencenumber;
} else {
// Old redundant data. Mark it for deletion.
$qa->observer->notify_step_deleted($nextstep, $qa);
}
} else {
$qa->steps[$i] = $nextstep;
if ($i == 0) {
$question->apply_attempt_state($qa->steps[0]);
}
$i++;
}
if ($records->valid()) {
$record = $records->current();
} else {
$record = false;
}
}
if ($autosavedstep) {
if ($autosavedsequencenumber >= $i) {
$qa->autosavedstep = $autosavedstep;
$qa->steps[$i] = $qa->autosavedstep;
} else {
$qa->observer->notify_step_deleted($autosavedstep, $qa);
}
}
return $qa;
}
/**
* Store an entire {@link question_attempt} in the database,
* including all the question_attempt_steps that comprise it.
* @param question_attempt $qa the question attempt to store.
* @param context $context the context of the owning question_usage_by_activity.
*/
public function insert_question_attempt(question_attempt $qa, $context)
{
$record = new stdClass();
$record->questionusageid = $qa->get_usage_id();
$record->slot = $qa->get_slot();
$record->behaviour = $qa->get_behaviour_name();
$record->questionid = $qa->get_question()->id;
$record->variant = $qa->get_variant();
$record->maxmark = $qa->get_max_mark();
$record->minfraction = $qa->get_min_fraction();
$record->maxfraction = $qa->get_max_fraction();
$record->flagged = $qa->is_flagged();
$record->questionsummary = $qa->get_question_summary();
if (core_text::strlen($record->questionsummary) > question_bank::MAX_SUMMARY_LENGTH) {
// It seems some people write very long quesions! MDL-30760
$record->questionsummary = core_text::substr($record->questionsummary, 0, question_bank::MAX_SUMMARY_LENGTH - 3) . '...';
}
$record->rightanswer = $qa->get_right_answer_summary();
$record->responsesummary = $qa->get_response_summary();
$record->timemodified = time();
$record->id = $this->db->insert_record('question_attempts', $record);
$qa->set_database_id($record->id);
foreach ($qa->get_step_iterator() as $seq => $step) {
$this->insert_question_attempt_step($step, $record->id, $seq, $context);
}
}
/**
* Create a question_attempt_step from records loaded from the database.
*
* For internal use only.
*
* @param Iterator $records Raw records loaded from the database.
* @param int $questionattemptid The id of the question_attempt to extract.
* @return question_attempt The newly constructed question_attempt.
*/
public static function load_from_records($records, $questionattemptid,
question_usage_observer $observer, $preferredbehaviour) {
$record = $records->current();
while ($record->questionattemptid != $questionattemptid) {
$record = $records->next();
if (!$records->valid()) {
throw new coding_exception("Question attempt $questionattemptid not found in the database.");
}
$record = $records->current();
}
try {
$question = question_bank::load_question($record->questionid);
} catch (Exception $e) {
// The question must have been deleted somehow. Create a missing
// question to use in its place.
$question = question_bank::get_qtype('missingtype')->make_deleted_instance(
$record->questionid, $record->maxmark + 0);
}
$qa = new question_attempt($question, $record->questionusageid,
null, $record->maxmark + 0);
$qa->set_database_id($record->questionattemptid);
$qa->set_slot($record->slot);
$qa->variant = $record->variant + 0;
$qa->minfraction = $record->minfraction + 0;
$qa->set_flagged($record->flagged);
$qa->questionsummary = $record->questionsummary;
$qa->rightanswer = $record->rightanswer;
$qa->responsesummary = $record->responsesummary;
$qa->timemodified = $record->timemodified;
$qa->behaviour = question_engine::make_behaviour(
$record->behaviour, $qa, $preferredbehaviour);
$i = 0;
while ($record && $record->questionattemptid == $questionattemptid && !is_null($record->attemptstepid)) {
$qa->steps[$i] = question_attempt_step::load_from_records($records, $record->attemptstepid);
if ($i == 0) {
$question->apply_attempt_state($qa->steps[0]);
}
$i++;
if ($records->valid()) {
$record = $records->current();
} else {
$record = false;
}
}
$qa->observer = $observer;
return $qa;
}
/**
* Regrade a question in this usage. This replays the sequence of submitted
* actions to recompute the outcomes.
* @param int $slot the number used to identify this question within this usage.
* @param bool $finished whether the question attempt should be forced to be finished
* after the regrade, or whether it may still be in progress (default false).
* @param number $newmaxmark (optional) if given, will change the max mark while regrading.
*/
public function regrade_question($slot, $finished = false, $newmaxmark = null) {
$oldqa = $this->get_question_attempt($slot);
if (is_null($newmaxmark)) {
$newmaxmark = $oldqa->get_max_mark();
}
$newqa = new question_attempt($oldqa->get_question(), $oldqa->get_usage_id(),
$this->observer, $newmaxmark);
$newqa->set_database_id($oldqa->get_database_id());
$newqa->set_slot($oldqa->get_slot());
$newqa->regrade($oldqa, $finished);
$this->questionattempts[$slot] = $newqa;
$this->observer->notify_attempt_modified($newqa);
}
/**
* Store an entire {@link question_attempt} in the database,
* including all the question_attempt_steps that comprise it.
*
* You should not call this method directly. You should use
* @link question_engine::save_questions_usage_by_activity()}.
*
* @param question_attempt $qa the question attempt to store.
* @param context $context the context of the owning question_usage_by_activity.
* @return array of question_attempt_step_data rows, that still need to be inserted.
*/
public function insert_question_attempt(question_attempt $qa, $context)
{
$record = new stdClass();
$record->questionusageid = $qa->get_usage_id();
$record->slot = $qa->get_slot();
$record->behaviour = $qa->get_behaviour_name();
$record->questionid = $qa->get_question()->id;
$record->variant = $qa->get_variant();
$record->maxmark = $qa->get_max_mark();
$record->minfraction = $qa->get_min_fraction();
$record->maxfraction = $qa->get_max_fraction();
$record->flagged = $qa->is_flagged();
$record->questionsummary = $qa->get_question_summary();
if (core_text::strlen($record->questionsummary) > question_bank::MAX_SUMMARY_LENGTH) {
// It seems some people write very long quesions! MDL-30760
$record->questionsummary = core_text::substr($record->questionsummary, 0, question_bank::MAX_SUMMARY_LENGTH - 3) . '...';
}
$record->rightanswer = $qa->get_right_answer_summary();
$record->responsesummary = $qa->get_response_summary();
$record->timemodified = time();
$record->id = $this->db->insert_record('question_attempts', $record);
$qa->set_database_id($record->id);
// Initially an array of array of question_attempt_step_objects.
// Built as a nested array for efficiency, then flattened.
$stepdata = array();
foreach ($qa->get_step_iterator() as $seq => $step) {
$stepdata[] = $this->insert_question_attempt_step($step, $record->id, $seq, $context);
}
return call_user_func_array('array_merge', $stepdata);
}
