/**
* 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;
}
/**
* Load a {@link question_attempt_step} from the database.
* @param int $stepid the id of the step to load.
* @param question_attempt_step the step that was loaded.
*/
public function load_question_attempt_step($stepid)
{
$records = $this->db->get_recordset_sql("\nSELECT\n quba.contextid,\n COALLESCE(q.qtype, 'missingtype') AS qtype,\n qas.id AS attemptstepid,\n qas.questionattemptid,\n qas.sequencenumber,\n qas.state,\n qas.fraction,\n qas.timecreated,\n qas.userid,\n qasd.name,\n qasd.value\n\nFROM {question_attempt_steps} qas\nJOIN {question_attempts} qa ON qa.id = qas.questionattemptid\nJOIN {question_usages} quba ON quba.id = qa.questionusageid\nLEFT JOIN {question} q ON q.id = qa.questionid\nLEFT JOIN {question_attempt_step_data} qasd ON qasd.attemptstepid = qas.id\n\nWHERE\n qas.id = :stepid\n ", array('stepid' => $stepid));
if (!$records->valid()) {
throw new coding_exception('Failed to load question_attempt_step ' . $stepid);
}
$step = question_attempt_step::load_from_records($records, $stepid);
$records->close();
return $step;
}
/**
* 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;
}
public function test_load_dont_be_too_greedy()
{
$records = new question_test_recordset(array(array('attemptstepid', 'questionattemptid', 'sequencenumber', 'state', 'fraction', 'timecreated', 'userid', 'name', 'value', 'contextid'), array(1, 1, 0, 'todo', null, 1256228502, 13, 'x', 'right', 1), array(2, 2, 0, 'complete', null, 1256228505, 13, 'x', 'wrong', 1)));
$step = question_attempt_step::load_from_records($records, 1, 'description');
$this->assertEquals(array('x' => 'right'), $step->get_all_data());
}
/**
* Load a {@link question_attempt_step} from the database.
* @param int $stepid the id of the step to load.
* @param question_attempt_step the step that was loaded.
*/
public function load_question_attempt_step($stepid) {
$records = $this->db->get_recordset_sql("
SELECT
qas.id AS attemptstepid,
qas.questionattemptid,
qas.sequencenumber,
qas.state,
qas.fraction,
qas.timecreated,
qas.userid,
qasd.name,
qasd.value
FROM {question_attempt_steps} qas
LEFT JOIN {question_attempt_step_data} qasd ON qasd.attemptstepid = qas.id
WHERE
qas.id = :stepid
", array('stepid' => $stepid));
if (!$records->valid()) {
throw new coding_exception('Failed to load question_attempt_step ' . $stepid);
}
$step = question_attempt_step::load_from_records($records, $stepid);
$records->close();
return $step;
}
