/question/engine/lib.php
PHP | 1229 lines | 547 code | 124 blank | 558 comment | 75 complexity | f7bcd8ac4058c9ecd7f1c9506c4268c9 MD5 | raw file
Possible License(s): BSD-3-Clause, MIT, GPL-3.0, Apache-2.0, LGPL-2.1
- <?php
- // This file is part of Moodle - http://moodle.org/
- //
- // Moodle is free software: you can redistribute it and/or modify
- // it under the terms of the GNU General Public License as published by
- // the Free Software Foundation, either version 3 of the License, or
- // (at your option) any later version.
- //
- // Moodle is distributed in the hope that it will be useful,
- // but WITHOUT ANY WARRANTY; without even the implied warranty of
- // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- // GNU General Public License for more details.
- //
- // You should have received a copy of the GNU General Public License
- // along with Moodle. If not, see <http://www.gnu.org/licenses/>.
- /**
- * This defines the core classes of the Moodle question engine.
- *
- * @package moodlecore
- * @subpackage questionengine
- * @copyright 2009 The Open University
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
- defined('MOODLE_INTERNAL') || die();
- require_once($CFG->libdir . '/filelib.php');
- require_once(__DIR__ . '/questionusage.php');
- require_once(__DIR__ . '/questionattempt.php');
- require_once(__DIR__ . '/questionattemptstep.php');
- require_once(__DIR__ . '/states.php');
- require_once(__DIR__ . '/datalib.php');
- require_once(__DIR__ . '/renderer.php');
- require_once(__DIR__ . '/bank.php');
- require_once(__DIR__ . '/../type/questiontypebase.php');
- require_once(__DIR__ . '/../type/questionbase.php');
- require_once(__DIR__ . '/../type/rendererbase.php');
- require_once(__DIR__ . '/../behaviour/behaviourtypebase.php');
- require_once(__DIR__ . '/../behaviour/behaviourbase.php');
- require_once(__DIR__ . '/../behaviour/rendererbase.php');
- require_once($CFG->libdir . '/questionlib.php');
- /**
- * This static class provides access to the other question engine classes.
- *
- * It provides functions for managing question behaviours), and for
- * creating, loading, saving and deleting {@link question_usage_by_activity}s,
- * which is the main class that is used by other code that wants to use questions.
- *
- * @copyright 2009 The Open University
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
- abstract class question_engine {
- /** @var array behaviour name => 1. Records which behaviours have been loaded. */
- private static $loadedbehaviours = array();
- /** @var array behaviour name => question_behaviour_type for this behaviour. */
- private static $behaviourtypes = array();
- /**
- * Create a new {@link question_usage_by_activity}. The usage is
- * created in memory. If you want it to persist, you will need to call
- * {@link save_questions_usage_by_activity()}.
- *
- * @param string $component the plugin creating this attempt. For example mod_quiz.
- * @param context $context the context this usage belongs to.
- * @return question_usage_by_activity the newly created object.
- */
- public static function make_questions_usage_by_activity($component, $context) {
- return new question_usage_by_activity($component, $context);
- }
- /**
- * Load a {@link question_usage_by_activity} from the database, based on its id.
- * @param int $qubaid the id of the usage to load.
- * @param moodle_database $db a database connectoin. Defaults to global $DB.
- * @return question_usage_by_activity loaded from the database.
- */
- public static function load_questions_usage_by_activity($qubaid, moodle_database $db = null) {
- $dm = new question_engine_data_mapper($db);
- return $dm->load_questions_usage_by_activity($qubaid);
- }
- /**
- * Save a {@link question_usage_by_activity} to the database. This works either
- * if the usage was newly created by {@link make_questions_usage_by_activity()}
- * or loaded from the database using {@link load_questions_usage_by_activity()}
- * @param question_usage_by_activity the usage to save.
- * @param moodle_database $db a database connectoin. Defaults to global $DB.
- */
- public static function save_questions_usage_by_activity(question_usage_by_activity $quba, moodle_database $db = null) {
- $dm = new question_engine_data_mapper($db);
- $observer = $quba->get_observer();
- if ($observer instanceof question_engine_unit_of_work) {
- $observer->save($dm);
- } else {
- $dm->insert_questions_usage_by_activity($quba);
- }
- }
- /**
- * Delete a {@link question_usage_by_activity} from the database, based on its id.
- * @param int $qubaid the id of the usage to delete.
- */
- public static function delete_questions_usage_by_activity($qubaid) {
- self::delete_questions_usage_by_activities(new qubaid_list(array($qubaid)));
- }
- /**
- * Delete {@link question_usage_by_activity}s from the database.
- * @param qubaid_condition $qubaids identifies which questions usages to delete.
- */
- public static function delete_questions_usage_by_activities(qubaid_condition $qubaids) {
- $dm = new question_engine_data_mapper();
- $dm->delete_questions_usage_by_activities($qubaids);
- }
- /**
- * Change the maxmark for the question_attempt with number in usage $slot
- * for all the specified question_attempts.
- * @param qubaid_condition $qubaids Selects which usages are updated.
- * @param int $slot the number is usage to affect.
- * @param number $newmaxmark the new max mark to set.
- */
- public static function set_max_mark_in_attempts(qubaid_condition $qubaids,
- $slot, $newmaxmark) {
- $dm = new question_engine_data_mapper();
- $dm->set_max_mark_in_attempts($qubaids, $slot, $newmaxmark);
- }
- /**
- * Validate that the manual grade submitted for a particular question is in range.
- * @param int $qubaid the question_usage id.
- * @param int $slot the slot number within the usage.
- * @return bool whether the submitted data is in range.
- */
- public static function is_manual_grade_in_range($qubaid, $slot) {
- $prefix = 'q' . $qubaid . ':' . $slot . '_';
- $mark = question_utils::optional_param_mark($prefix . '-mark');
- $maxmark = optional_param($prefix . '-maxmark', null, PARAM_FLOAT);
- $minfraction = optional_param($prefix . ':minfraction', null, PARAM_FLOAT);
- $maxfraction = optional_param($prefix . ':maxfraction', null, PARAM_FLOAT);
- return $mark === '' ||
- ($mark !== null && $mark >= $minfraction * $maxmark && $mark <= $maxfraction * $maxmark) ||
- ($mark === null && $maxmark === null);
- }
- /**
- * @param array $questionids of question ids.
- * @param qubaid_condition $qubaids ids of the usages to consider.
- * @return boolean whether any of these questions are being used by any of
- * those usages.
- */
- public static function questions_in_use(array $questionids, qubaid_condition $qubaids = null) {
- if (is_null($qubaids)) {
- return false;
- }
- $dm = new question_engine_data_mapper();
- return $dm->questions_in_use($questionids, $qubaids);
- }
- /**
- * Get the number of times each variant has been used for each question in a list
- * in a set of usages.
- * @param array $questionids of question ids.
- * @param qubaid_condition $qubaids ids of the usages to consider.
- * @return array questionid => variant number => num uses.
- */
- public static function load_used_variants(array $questionids, qubaid_condition $qubaids) {
- $dm = new question_engine_data_mapper();
- return $dm->load_used_variants($questionids, $qubaids);
- }
- /**
- * Create an archetypal behaviour for a particular question attempt.
- * Used by {@link question_definition::make_behaviour()}.
- *
- * @param string $preferredbehaviour the type of model required.
- * @param question_attempt $qa the question attempt the model will process.
- * @return question_behaviour an instance of appropriate behaviour class.
- */
- public static function make_archetypal_behaviour($preferredbehaviour, question_attempt $qa) {
- if (!self::is_behaviour_archetypal($preferredbehaviour)) {
- throw new coding_exception('The requested behaviour is not actually ' .
- 'an archetypal one.');
- }
- self::load_behaviour_class($preferredbehaviour);
- $class = 'qbehaviour_' . $preferredbehaviour;
- return new $class($qa, $preferredbehaviour);
- }
- /**
- * @param string $behaviour the name of a behaviour.
- * @return array of {@link question_display_options} field names, that are
- * not relevant to this behaviour before a 'finish' action.
- */
- public static function get_behaviour_unused_display_options($behaviour) {
- return self::get_behaviour_type($behaviour)->get_unused_display_options();
- }
- /**
- * With this behaviour, is it possible that a question might finish as the student
- * interacts with it, without a call to the {@link question_attempt::finish()} method?
- * @param string $behaviour the name of a behaviour. E.g. 'deferredfeedback'.
- * @return bool whether with this behaviour, questions may finish naturally.
- */
- public static function can_questions_finish_during_the_attempt($behaviour) {
- return self::get_behaviour_type($behaviour)->can_questions_finish_during_the_attempt();
- }
- /**
- * Create a behaviour for a particular type. If that type cannot be
- * found, return an instance of qbehaviour_missing.
- *
- * Normally you should use {@link make_archetypal_behaviour()}, or
- * call the constructor of a particular model class directly. This method
- * is only intended for use by {@link question_attempt::load_from_records()}.
- *
- * @param string $behaviour the type of model to create.
- * @param question_attempt $qa the question attempt the model will process.
- * @param string $preferredbehaviour the preferred behaviour for the containing usage.
- * @return question_behaviour an instance of appropriate behaviour class.
- */
- public static function make_behaviour($behaviour, question_attempt $qa, $preferredbehaviour) {
- try {
- self::load_behaviour_class($behaviour);
- } catch (Exception $e) {
- self::load_behaviour_class('missing');
- return new qbehaviour_missing($qa, $preferredbehaviour);
- }
- $class = 'qbehaviour_' . $behaviour;
- return new $class($qa, $preferredbehaviour);
- }
- /**
- * Load the behaviour class(es) belonging to a particular model. That is,
- * include_once('/question/behaviour/' . $behaviour . '/behaviour.php'), with a bit
- * of checking.
- * @param string $qtypename the question type name. For example 'multichoice' or 'shortanswer'.
- */
- public static function load_behaviour_class($behaviour) {
- global $CFG;
- if (isset(self::$loadedbehaviours[$behaviour])) {
- return;
- }
- $file = $CFG->dirroot . '/question/behaviour/' . $behaviour . '/behaviour.php';
- if (!is_readable($file)) {
- throw new coding_exception('Unknown question behaviour ' . $behaviour);
- }
- include_once($file);
- $class = 'qbehaviour_' . $behaviour;
- if (!class_exists($class)) {
- throw new coding_exception('Question behaviour ' . $behaviour .
- ' does not define the required class ' . $class . '.');
- }
- self::$loadedbehaviours[$behaviour] = 1;
- }
- /**
- * Create a behaviour for a particular type. If that type cannot be
- * found, return an instance of qbehaviour_missing.
- *
- * Normally you should use {@link make_archetypal_behaviour()}, or
- * call the constructor of a particular model class directly. This method
- * is only intended for use by {@link question_attempt::load_from_records()}.
- *
- * @param string $behaviour the type of model to create.
- * @param question_attempt $qa the question attempt the model will process.
- * @param string $preferredbehaviour the preferred behaviour for the containing usage.
- * @return question_behaviour_type an instance of appropriate behaviour class.
- */
- public static function get_behaviour_type($behaviour) {
- if (array_key_exists($behaviour, self::$behaviourtypes)) {
- return self::$behaviourtypes[$behaviour];
- }
- self::load_behaviour_type_class($behaviour);
- $class = 'qbehaviour_' . $behaviour . '_type';
- if (class_exists($class)) {
- self::$behaviourtypes[$behaviour] = new $class();
- } else {
- debugging('Question behaviour ' . $behaviour .
- ' does not define the required class ' . $class . '.', DEBUG_DEVELOPER);
- self::$behaviourtypes[$behaviour] = new question_behaviour_type_fallback($behaviour);
- }
- return self::$behaviourtypes[$behaviour];
- }
- /**
- * Load the behaviour type class for a particular behaviour. That is,
- * include_once('/question/behaviour/' . $behaviour . '/behaviourtype.php').
- * @param string $behaviour the behaviour name. For example 'interactive' or 'deferredfeedback'.
- */
- protected static function load_behaviour_type_class($behaviour) {
- global $CFG;
- if (isset(self::$behaviourtypes[$behaviour])) {
- return;
- }
- $file = $CFG->dirroot . '/question/behaviour/' . $behaviour . '/behaviourtype.php';
- if (!is_readable($file)) {
- debugging('Question behaviour ' . $behaviour .
- ' is missing the behaviourtype.php file.', DEBUG_DEVELOPER);
- }
- include_once($file);
- }
- /**
- * Return an array where the keys are the internal names of the archetypal
- * behaviours, and the values are a human-readable name. An
- * archetypal behaviour is one that is suitable to pass the name of to
- * {@link question_usage_by_activity::set_preferred_behaviour()}.
- *
- * @return array model name => lang string for this behaviour name.
- */
- public static function get_archetypal_behaviours() {
- $archetypes = array();
- $behaviours = core_component::get_plugin_list('qbehaviour');
- foreach ($behaviours as $behaviour => $notused) {
- if (self::is_behaviour_archetypal($behaviour)) {
- $archetypes[$behaviour] = self::get_behaviour_name($behaviour);
- }
- }
- asort($archetypes, SORT_LOCALE_STRING);
- return $archetypes;
- }
- /**
- * @param string $behaviour the name of a behaviour. E.g. 'deferredfeedback'.
- * @return bool whether this is an archetypal behaviour.
- */
- public static function is_behaviour_archetypal($behaviour) {
- return self::get_behaviour_type($behaviour)->is_archetypal();
- }
- /**
- * Return an array where the keys are the internal names of the behaviours
- * in preferred order and the values are a human-readable name.
- *
- * @param array $archetypes, array of behaviours
- * @param string $orderlist, a comma separated list of behaviour names
- * @param string $disabledlist, a comma separated list of behaviour names
- * @param string $current, current behaviour name
- * @return array model name => lang string for this behaviour name.
- */
- public static function sort_behaviours($archetypes, $orderlist, $disabledlist, $current=null) {
- // Get disabled behaviours
- if ($disabledlist) {
- $disabled = explode(',', $disabledlist);
- } else {
- $disabled = array();
- }
- if ($orderlist) {
- $order = explode(',', $orderlist);
- } else {
- $order = array();
- }
- foreach ($disabled as $behaviour) {
- if (array_key_exists($behaviour, $archetypes) && $behaviour != $current) {
- unset($archetypes[$behaviour]);
- }
- }
- // Get behaviours in preferred order
- $behaviourorder = array();
- foreach ($order as $behaviour) {
- if (array_key_exists($behaviour, $archetypes)) {
- $behaviourorder[$behaviour] = $archetypes[$behaviour];
- }
- }
- // Get the rest of behaviours and sort them alphabetically
- $leftover = array_diff_key($archetypes, $behaviourorder);
- asort($leftover, SORT_LOCALE_STRING);
- // Set up the final order to be displayed
- return $behaviourorder + $leftover;
- }
- /**
- * Return an array where the keys are the internal names of the behaviours
- * in preferred order and the values are a human-readable name.
- *
- * @param string $currentbehaviour
- * @return array model name => lang string for this behaviour name.
- */
- public static function get_behaviour_options($currentbehaviour) {
- $config = question_bank::get_config();
- $archetypes = self::get_archetypal_behaviours();
- // If no admin setting return all behavious
- if (empty($config->disabledbehaviours) && empty($config->behavioursortorder)) {
- return $archetypes;
- }
- if (empty($config->behavioursortorder)) {
- $order = '';
- } else {
- $order = $config->behavioursortorder;
- }
- if (empty($config->disabledbehaviours)) {
- $disabled = '';
- } else {
- $disabled = $config->disabledbehaviours;
- }
- return self::sort_behaviours($archetypes, $order, $disabled, $currentbehaviour);
- }
- /**
- * Get the translated name of a behaviour, for display in the UI.
- * @param string $behaviour the internal name of the model.
- * @return string name from the current language pack.
- */
- public static function get_behaviour_name($behaviour) {
- return get_string('pluginname', 'qbehaviour_' . $behaviour);
- }
- /**
- * @return array all the file area names that may contain response files.
- */
- public static function get_all_response_file_areas() {
- $variables = array();
- foreach (question_bank::get_all_qtypes() as $qtype) {
- $variables = array_merge($variables, $qtype->response_file_areas());
- }
- $areas = array();
- foreach (array_unique($variables) as $variable) {
- $areas[] = 'response_' . $variable;
- }
- return $areas;
- }
- /**
- * Returns the valid choices for the number of decimal places for showing
- * question marks. For use in the user interface.
- * @return array suitable for passing to {@link html_writer::select()} or similar.
- */
- public static function get_dp_options() {
- return question_display_options::get_dp_options();
- }
- /**
- * Initialise the JavaScript required on pages where questions will be displayed.
- *
- * @return string
- */
- public static function initialise_js() {
- return question_flags::initialise_js();
- }
- }
- /**
- * This class contains all the options that controls how a question is displayed.
- *
- * Normally, what will happen is that the calling code will set up some display
- * options to indicate what sort of question display it wants, and then before the
- * question is rendered, the behaviour will be given a chance to modify the
- * display options, so that, for example, A question that is finished will only
- * be shown read-only, and a question that has not been submitted will not have
- * any sort of feedback displayed.
- *
- * @copyright 2009 The Open University
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
- class question_display_options {
- /**#@+
- * @var integer named constants for the values that most of the options take.
- */
- const SHOW_ALL = -1;
- const HIDDEN = 0;
- const VISIBLE = 1;
- const EDITABLE = 2;
- /**#@-*/
- /**#@+ @var integer named constants for the {@link $marks} option. */
- const MAX_ONLY = 1;
- const MARK_AND_MAX = 2;
- /**#@-*/
- /**
- * @var integer maximum value for the {@link $markpd} option. This is
- * effectively set by the database structure, which uses NUMBER(12,7) columns
- * for question marks/fractions.
- */
- const MAX_DP = 7;
- /**
- * @var boolean whether the question should be displayed as a read-only review,
- * or in an active state where you can change the answer.
- */
- public $readonly = false;
- /**
- * @var boolean whether the question type should output hidden form fields
- * to reset any incorrect parts of the resonse to blank.
- */
- public $clearwrong = false;
- /**
- * Should the student have what they got right and wrong clearly indicated.
- * This includes the green/red hilighting of the bits of their response,
- * whether the one-line summary of the current state of the question says
- * correct/incorrect or just answered.
- * @var integer {@link question_display_options::HIDDEN} or
- * {@link question_display_options::VISIBLE}
- */
- public $correctness = self::VISIBLE;
- /**
- * The the mark and/or the maximum available mark for this question be visible?
- * @var integer {@link question_display_options::HIDDEN},
- * {@link question_display_options::MAX_ONLY} or {@link question_display_options::MARK_AND_MAX}
- */
- public $marks = self::MARK_AND_MAX;
- /** @var number of decimal places to use when formatting marks for output. */
- public $markdp = 2;
- /**
- * Should the flag this question UI element be visible, and if so, should the
- * flag state be changable?
- * @var integer {@link question_display_options::HIDDEN},
- * {@link question_display_options::VISIBLE} or {@link question_display_options::EDITABLE}
- */
- public $flags = self::VISIBLE;
- /**
- * Should the specific feedback be visible.
- * @var integer {@link question_display_options::HIDDEN} or
- * {@link question_display_options::VISIBLE}
- */
- public $feedback = self::VISIBLE;
- /**
- * For questions with a number of sub-parts (like matching, or
- * multiple-choice, multiple-reponse) display the number of sub-parts that
- * were correct.
- * @var integer {@link question_display_options::HIDDEN} or
- * {@link question_display_options::VISIBLE}
- */
- public $numpartscorrect = self::VISIBLE;
- /**
- * Should the general feedback be visible?
- * @var integer {@link question_display_options::HIDDEN} or
- * {@link question_display_options::VISIBLE}
- */
- public $generalfeedback = self::VISIBLE;
- /**
- * Should the automatically generated display of what the correct answer is
- * be visible?
- * @var integer {@link question_display_options::HIDDEN} or
- * {@link question_display_options::VISIBLE}
- */
- public $rightanswer = self::VISIBLE;
- /**
- * Should the manually added marker's comment be visible. Should the link for
- * adding/editing the comment be there.
- * @var integer {@link question_display_options::HIDDEN},
- * {@link question_display_options::VISIBLE}, or {@link question_display_options::EDITABLE}.
- * Editable means that form fields are displayed inline.
- */
- public $manualcomment = self::VISIBLE;
- /**
- * Should we show a 'Make comment or override grade' link?
- * @var string base URL for the edit comment script, which will be shown if
- * $manualcomment = self::VISIBLE.
- */
- public $manualcommentlink = null;
- /**
- * Used in places like the question history table, to show a link to review
- * this question in a certain state. If blank, a link is not shown.
- * @var moodle_url base URL for a review question script.
- */
- public $questionreviewlink = null;
- /**
- * Should the history of previous question states table be visible?
- * @var integer {@link question_display_options::HIDDEN} or
- * {@link question_display_options::VISIBLE}
- */
- public $history = self::HIDDEN;
- /**
- * @since 2.9
- * @var string extra HTML to include at the end of the outcome (feedback) box
- * of the question display.
- *
- * This field is now badly named. The place it included is was changed
- * (for the better) but the name was left unchanged for backwards compatibility.
- */
- public $extrainfocontent = '';
- /**
- * @since 2.9
- * @var string extra HTML to include in the history box of the question display,
- * if it is shown.
- */
- public $extrahistorycontent = '';
- /**
- * If not empty, then a link to edit the question will be included in
- * the info box for the question.
- *
- * If used, this array must contain an element courseid or cmid.
- *
- * It shoudl also contain a parameter returnurl => moodle_url giving a
- * sensible URL to go back to when the editing form is submitted or cancelled.
- *
- * @var array url parameter for the edit link. id => questiosnid will be
- * added automatically.
- */
- public $editquestionparams = array();
- /**
- * @var context the context the attempt being output belongs to.
- */
- public $context;
- /**
- * @var int The option to show the action author in the response history.
- */
- public $userinfoinhistory = self::HIDDEN;
- /**
- * Set all the feedback-related fields {@link $feedback}, {@link generalfeedback},
- * {@link rightanswer} and {@link manualcomment} to
- * {@link question_display_options::HIDDEN}.
- */
- public function hide_all_feedback() {
- $this->feedback = self::HIDDEN;
- $this->numpartscorrect = self::HIDDEN;
- $this->generalfeedback = self::HIDDEN;
- $this->rightanswer = self::HIDDEN;
- $this->manualcomment = self::HIDDEN;
- $this->correctness = self::HIDDEN;
- }
- /**
- * Returns the valid choices for the number of decimal places for showing
- * question marks. For use in the user interface.
- *
- * Calling code should probably use {@link question_engine::get_dp_options()}
- * rather than calling this method directly.
- *
- * @return array suitable for passing to {@link html_writer::select()} or similar.
- */
- public static function get_dp_options() {
- $options = array();
- for ($i = 0; $i <= self::MAX_DP; $i += 1) {
- $options[$i] = $i;
- }
- return $options;
- }
- }
- /**
- * Contains the logic for handling question flags.
- *
- * @copyright 2010 The Open University
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
- abstract class question_flags {
- /**
- * Get the checksum that validates that a toggle request is valid.
- * @param int $qubaid the question usage id.
- * @param int $questionid the question id.
- * @param int $sessionid the question_attempt id.
- * @param object $user the user. If null, defaults to $USER.
- * @return string that needs to be sent to question/toggleflag.php for it to work.
- */
- protected static function get_toggle_checksum($qubaid, $questionid,
- $qaid, $slot, $user = null) {
- if (is_null($user)) {
- global $USER;
- $user = $USER;
- }
- return md5($qubaid . "_" . $user->secret . "_" . $questionid . "_" . $qaid . "_" . $slot);
- }
- /**
- * Get the postdata that needs to be sent to question/toggleflag.php to change the flag state.
- * You need to append &newstate=0/1 to this.
- * @return the post data to send.
- */
- public static function get_postdata(question_attempt $qa) {
- $qaid = $qa->get_database_id();
- $qubaid = $qa->get_usage_id();
- $qid = $qa->get_question_id();
- $slot = $qa->get_slot();
- $checksum = self::get_toggle_checksum($qubaid, $qid, $qaid, $slot);
- return "qaid={$qaid}&qubaid={$qubaid}&qid={$qid}&slot={$slot}&checksum={$checksum}&sesskey=" .
- sesskey() . '&newstate=';
- }
- /**
- * If the request seems valid, update the flag state of a question attempt.
- * Throws exceptions if this is not a valid update request.
- * @param int $qubaid the question usage id.
- * @param int $questionid the question id.
- * @param int $sessionid the question_attempt id.
- * @param string $checksum checksum, as computed by {@link get_toggle_checksum()}
- * corresponding to the last three arguments.
- * @param bool $newstate the new state of the flag. true = flagged.
- */
- public static function update_flag($qubaid, $questionid, $qaid, $slot, $checksum, $newstate) {
- // Check the checksum - it is very hard to know who a question session belongs
- // to, so we require that checksum parameter is matches an md5 hash of the
- // three ids and the users username. Since we are only updating a flag, that
- // probably makes it sufficiently difficult for malicious users to toggle
- // other users flags.
- if ($checksum != self::get_toggle_checksum($qubaid, $questionid, $qaid, $slot)) {
- throw new moodle_exception('errorsavingflags', 'question');
- }
- $dm = new question_engine_data_mapper();
- $dm->update_question_attempt_flag($qubaid, $questionid, $qaid, $slot, $newstate);
- }
- public static function initialise_js() {
- global $CFG, $PAGE, $OUTPUT;
- static $done = false;
- if ($done) {
- return;
- }
- $module = array(
- 'name' => 'core_question_flags',
- 'fullpath' => '/question/flags.js',
- 'requires' => array('base', 'dom', 'event-delegate', 'io-base'),
- );
- $actionurl = $CFG->wwwroot . '/question/toggleflag.php';
- $flagtext = array(
- 0 => get_string('clickflag', 'question'),
- 1 => get_string('clickunflag', 'question')
- );
- $flagattributes = array(
- 0 => array(
- 'src' => $OUTPUT->image_url('i/unflagged') . '',
- 'title' => get_string('clicktoflag', 'question'),
- 'alt' => get_string('notflagged', 'question'),
- // 'text' => get_string('clickflag', 'question'),
- ),
- 1 => array(
- 'src' => $OUTPUT->image_url('i/flagged') . '',
- 'title' => get_string('clicktounflag', 'question'),
- 'alt' => get_string('flagged', 'question'),
- // 'text' => get_string('clickunflag', 'question'),
- ),
- );
- $PAGE->requires->js_init_call('M.core_question_flags.init',
- array($actionurl, $flagattributes, $flagtext), false, $module);
- $done = true;
- }
- }
- /**
- * Exception thrown when the system detects that a student has done something
- * out-of-order to a question. This can happen, for example, if they click
- * the browser's back button in a quiz, then try to submit a different response.
- *
- * @copyright 2010 The Open University
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
- class question_out_of_sequence_exception extends moodle_exception {
- public function __construct($qubaid, $slot, $postdata) {
- if ($postdata == null) {
- $postdata = data_submitted();
- }
- parent::__construct('submissionoutofsequence', 'question', '', null,
- "QUBAid: {$qubaid}, slot: {$slot}, post data: " . print_r($postdata, true));
- }
- }
- /**
- * Useful functions for writing question types and behaviours.
- *
- * @copyright 2010 The Open University
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
- abstract class question_utils {
- /**
- * @var float tolerance to use when comparing question mark/fraction values.
- *
- * When comparing floating point numbers in a computer, the representation is not
- * necessarily exact. Therefore, we need to allow a tolerance.
- * Question marks are stored in the database as decimal numbers with 7 decimal places.
- * Therefore, this is the appropriate tolerance to use.
- */
- const MARK_TOLERANCE = 0.00000005;
- /**
- * Tests to see whether two arrays have the same keys, with the same values
- * (as compared by ===) for each key. However, the order of the arrays does
- * not have to be the same.
- * @param array $array1 the first array.
- * @param array $array2 the second array.
- * @return bool whether the two arrays have the same keys with the same
- * corresponding values.
- */
- public static function arrays_have_same_keys_and_values(array $array1, array $array2) {
- if (count($array1) != count($array2)) {
- return false;
- }
- foreach ($array1 as $key => $value1) {
- if (!array_key_exists($key, $array2)) {
- return false;
- }
- if (((string) $value1) !== ((string) $array2[$key])) {
- return false;
- }
- }
- return true;
- }
- /**
- * Tests to see whether two arrays have the same value at a particular key.
- * This method will return true if:
- * 1. Neither array contains the key; or
- * 2. Both arrays contain the key, and the corresponding values compare
- * identical when cast to strings and compared with ===.
- * @param array $array1 the first array.
- * @param array $array2 the second array.
- * @param string $key an array key.
- * @return bool whether the two arrays have the same value (or lack of
- * one) for a given key.
- */
- public static function arrays_same_at_key(array $array1, array $array2, $key) {
- if (array_key_exists($key, $array1) && array_key_exists($key, $array2)) {
- return ((string) $array1[$key]) === ((string) $array2[$key]);
- }
- if (!array_key_exists($key, $array1) && !array_key_exists($key, $array2)) {
- return true;
- }
- return false;
- }
- /**
- * Tests to see whether two arrays have the same value at a particular key.
- * Missing values are replaced by '', and then the values are cast to
- * strings and compared with ===.
- * @param array $array1 the first array.
- * @param array $array2 the second array.
- * @param string $key an array key.
- * @return bool whether the two arrays have the same value (or lack of
- * one) for a given key.
- */
- public static function arrays_same_at_key_missing_is_blank(
- array $array1, array $array2, $key) {
- if (array_key_exists($key, $array1)) {
- $value1 = $array1[$key];
- } else {
- $value1 = '';
- }
- if (array_key_exists($key, $array2)) {
- $value2 = $array2[$key];
- } else {
- $value2 = '';
- }
- return ((string) $value1) === ((string) $value2);
- }
- /**
- * Tests to see whether two arrays have the same value at a particular key.
- * Missing values are replaced by 0, and then the values are cast to
- * integers and compared with ===.
- * @param array $array1 the first array.
- * @param array $array2 the second array.
- * @param string $key an array key.
- * @return bool whether the two arrays have the same value (or lack of
- * one) for a given key.
- */
- public static function arrays_same_at_key_integer(
- array $array1, array $array2, $key) {
- if (array_key_exists($key, $array1)) {
- $value1 = (int) $array1[$key];
- } else {
- $value1 = 0;
- }
- if (array_key_exists($key, $array2)) {
- $value2 = (int) $array2[$key];
- } else {
- $value2 = 0;
- }
- return $value1 === $value2;
- }
- private static $units = array('', 'i', 'ii', 'iii', 'iv', 'v', 'vi', 'vii', 'viii', 'ix');
- private static $tens = array('', 'x', 'xx', 'xxx', 'xl', 'l', 'lx', 'lxx', 'lxxx', 'xc');
- private static $hundreds = array('', 'c', 'cc', 'ccc', 'cd', 'd', 'dc', 'dcc', 'dccc', 'cm');
- private static $thousands = array('', 'm', 'mm', 'mmm');
- /**
- * Convert an integer to roman numerals.
- * @param int $number an integer between 1 and 3999 inclusive. Anything else
- * will throw an exception.
- * @return string the number converted to lower case roman numerals.
- */
- public static function int_to_roman($number) {
- if (!is_integer($number) || $number < 1 || $number > 3999) {
- throw new coding_exception('Only integers between 0 and 3999 can be ' .
- 'converted to roman numerals.', $number);
- }
- return self::$thousands[$number / 1000 % 10] . self::$hundreds[$number / 100 % 10] .
- self::$tens[$number / 10 % 10] . self::$units[$number % 10];
- }
- /**
- * Convert an integer to a letter of alphabet.
- * @param int $number an integer between 1 and 26 inclusive.
- * Anything else will throw an exception.
- * @return string the number converted to upper case letter of alphabet.
- */
- public static function int_to_letter($number) {
- $alphabet = [
- '1' => 'A',
- '2' => 'B',
- '3' => 'C',
- '4' => 'D',
- '5' => 'E',
- '6' => 'F',
- '7' => 'G',
- '8' => 'H',
- '9' => 'I',
- '10' => 'J',
- '11' => 'K',
- '12' => 'L',
- '13' => 'M',
- '14' => 'N',
- '15' => 'O',
- '16' => 'P',
- '17' => 'Q',
- '18' => 'R',
- '19' => 'S',
- '20' => 'T',
- '21' => 'U',
- '22' => 'V',
- '23' => 'W',
- '24' => 'X',
- '25' => 'Y',
- '26' => 'Z'
- ];
- if (!is_integer($number) || $number < 1 || $number > count($alphabet)) {
- throw new coding_exception('Only integers between 1 and 26 can be converted to letters.', $number);
- }
- return $alphabet[$number];
- }
- /**
- * Typically, $mark will have come from optional_param($name, null, PARAM_RAW_TRIMMED).
- * This method copes with:
- * - keeping null or '' input unchanged - important to let teaches set a question back to requries grading.
- * - numbers that were typed as either 1.00 or 1,00 form.
- * - invalid things, which get turned into null.
- *
- * @param string|null $mark raw use input of a mark.
- * @return float|string|null cleaned mark as a float if possible. Otherwise '' or null.
- */
- public static function clean_param_mark($mark) {
- if ($mark === '' || is_null($mark)) {
- return $mark;
- }
- $mark = str_replace(',', '.', $mark);
- // This regexp should match the one in validate_param.
- if (!preg_match('/^[\+-]?[0-9]*\.?[0-9]*(e[-+]?[0-9]+)?$/i', $mark)) {
- return null;
- }
- return clean_param($mark, PARAM_FLOAT);
- }
- /**
- * Get a sumitted variable (from the GET or POST data) that is a mark.
- * @param string $parname the submitted variable name.
- * @return float|string|null cleaned mark as a float if possible. Otherwise '' or null.
- */
- public static function optional_param_mark($parname) {
- return self::clean_param_mark(
- optional_param($parname, null, PARAM_RAW_TRIMMED));
- }
- /**
- * Convert part of some question content to plain text.
- * @param string $text the text.
- * @param int $format the text format.
- * @param array $options formatting options. Passed to {@link format_text}.
- * @return float|string|null cleaned mark as a float if possible. Otherwise '' or null.
- */
- public static function to_plain_text($text, $format, $options = array('noclean' => 'true')) {
- // The following call to html_to_text uses the option that strips out
- // all URLs, but format_text complains if it finds @@PLUGINFILE@@ tokens.
- // So, we need to replace @@PLUGINFILE@@ with a real URL, but it doesn't
- // matter what. We use http://example.com/.
- $text = str_replace('@@PLUGINFILE@@/', 'http://example.com/', $text);
- return html_to_text(format_text($text, $format, $options), 0, false);
- }
- /**
- * Get the options required to configure the filepicker for one of the editor
- * toolbar buttons.
- *
- * @param mixed $acceptedtypes array of types of '*'.
- * @param int $draftitemid the draft area item id.
- * @param context $context the context.
- * @return object the required options.
- */
- protected static function specific_filepicker_options($acceptedtypes, $draftitemid, $context) {
- $filepickeroptions = new stdClass();
- $filepickeroptions->accepted_types = $acceptedtypes;
- $filepickeroptions->return_types = FILE_INTERNAL | FILE_EXTERNAL;
- $filepickeroptions->context = $context;
- $filepickeroptions->env = 'filepicker';
- $options = initialise_filepicker($filepickeroptions);
- $options->context = $context;
- $options->client_id = uniqid();
- $options->env = 'editor';
- $options->itemid = $draftitemid;
- return $options;
- }
- /**
- * Get filepicker options for question related text areas.
- *
- * @param context $context the context.
- * @param int $draftitemid the draft area item id.
- * @return array An array of options
- */
- public static function get_filepicker_options($context, $draftitemid) {
- return [
- 'image' => self::specific_filepicker_options(['image'], $draftitemid, $context),
- 'media' => self::specific_filepicker_options(['video', 'audio'], $draftitemid, $context),
- 'link' => self::specific_filepicker_options('*', $draftitemid, $context),
- ];
- }
- /**
- * Get editor options for question related text areas.
- *
- * @param context $context the context.
- * @return array An array of options
- */
- public static function get_editor_options($context) {
- global $CFG;
- $editoroptions = [
- 'subdirs' => 0,
- 'context' => $context,
- 'maxfiles' => EDITOR_UNLIMITED_FILES,
- 'maxbytes' => $CFG->maxbytes,
- 'noclean' => 0,
- 'trusttext' => 0,
- 'autosave' => false
- ];
- return $editoroptions;
- }
- }
- /**
- * The interface for strategies for controlling which variant of each question is used.
- *
- * @copyright 2011 The Open University
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
- interface question_variant_selection_strategy {
- /**
- * @param int $maxvariants the num
- * @param string $seed data that can be used to controls how the variant is selected
- * in a semi-random way.
- * @return int the variant to use, a number betweeb 1 and $maxvariants inclusive.
- */
- public function choose_variant($maxvariants, $seed);
- }
- /**
- * A {@link question_variant_selection_strategy} that is completely random.
- *
- * @copyright 2011 The Open University
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
- class question_variant_random_strategy implements question_variant_selection_strategy {
- public function choose_variant($maxvariants, $seed) {
- return rand(1, $maxvariants);
- }
- }
- /**
- * A {@link question_variant_selection_strategy} that is effectively random
- * for the first attempt, and then after that cycles through the available
- * variants so that the students will not get a repeated variant until they have
- * seen them all.
- *
- * @copyright 2011 The Open University
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
- class question_variant_pseudorandom_no_repeats_strategy
- implements question_variant_selection_strategy {
- /** @var int the number of attempts this users has had, including the curent one. */
- protected $attemptno;
- /** @var int the user id the attempt belongs to. */
- protected $userid;
- /** @var string extra input fed into the pseudo-random code. */
- protected $extrarandomness = '';
- /**
- * Constructor.
- * @param int $attemptno The attempt number.
- * @param int $userid the user the attempt is for (defaults to $USER->id).
- */
- public function __construct($attemptno, $userid = null, $extrarandomness = '') {
- $this->attemptno = $attemptno;
- if (is_null($userid)) {
- global $USER;
- $this->userid = $USER->id;
- } else {
- $this->userid = $userid;
- }
- if ($extrarandomness) {
- $this->extrarandomness = '|' . $extrarandomness;
- }
- }
- public function choose_variant($maxvariants, $seed) {
- if ($maxvariants == 1) {
- return 1;
- }
- $hash = sha1($seed . '|user' . $this->userid . $this->extrarandomness);
- $randint = hexdec(substr($hash, 17, 7));
- return ($randint + $this->attemptno) % $maxvariants + 1;
- }
- }
- /**
- * A {@link question_variant_selection_strategy} designed ONLY for testing.
- * For selected questions it wil return a specific variants. For the other
- * slots it will use a fallback strategy.
- *
- * @copyright 2013 The Open University
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- */
- class question_variant_forced_choices_selection_strategy
- implements question_variant_selection_strategy {
- /** @var array seed => variant to select. */
- protected $forcedchoices;
- /** @var question_variant_selection_strategy strategy used to make the non-forced choices. */
- protected $basestrategy;
- /**
- * Constructor.
- * @param array $forcedchoices array seed => variant to select.
- * @param question_variant_selection_strategy $basestrategy strategy used
- * to make the non-forced choices.
- */
- public function __construct(array $forcedchoices, question_variant_selection_strategy $basestrategy) {
- $this->forcedchoices = $forcedchoices;
- $this->basestrategy = $basestrategy;
- }
- public function choose_variant($maxvariants, $seed) {
- if (array_key_exists($seed, $this->forcedchoices)) {
- if ($this->forcedchoices[$seed] > $maxvariants) {
- throw new coding_exception('Forced variant out of range.');
- }
- return $this->forcedchoices[$seed];
- } else {
- return $this->basestrategy->choose_variant($maxvariants, $seed);
- }
- }
- /**
- * Helper method for preparing the $forcedchoices array.
- * @param array $variantsbyslot slot number => variant to select.
- * @param question_usage_by_activity $quba the question usage we need a strategy for.
- * @throws coding_exception when variant cannot be forced as doesn't work.
- * @return array that can be passed to the constructor as $forcedchoices.
- */
- public static function prepare_forced_choices_array(array $variantsbyslot,
- question_usage_by_activity $quba) {
- $forcedchoices = array();
- foreach ($variantsbyslot as $slot => $varianttochoose) {
- $question = $quba->get_question($slot);
- $seed = $question->get_variants_selection_seed();
- if (array_key_exists($seed, $forcedchoices) && $forcedchoices[$seed] != $varianttochoose) {
- throw new coding_exception('Inconsistent forced variant detected at slot ' . $slot);
- }
- if ($varianttochoose > $question->get_num_variants()) {
- throw new coding_exception('Forced variant out of range at slot ' . $slot);
- }
- $forcedchoices[$seed] = $varianttochoose;
- }
- return $forcedchoices;
- }
- }