MDL-71410 mod_lesson: Cache user and group overrides

mod/lesson/classes/cache/overrides.php

@@ -0,0 +1,110 @@
+<?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/>.
+
+/**
+ * Cache data source for the lesson overrides.
+ *
+ * @package   mod_lesson
+ * @copyright 2021 Shamim Rezaie <shamim@moodle.com>
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+declare(strict_types=1);
+
+namespace mod_lesson\cache;
+
+use cache_definition;
+
+/**
+ * Class lesson_overrides
+ *
+ * @package   mod_lesson
+ * @copyright 2021 Shamim Rezaie <shamim@moodle.com>
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class overrides implements \cache_data_source {
+
+    /** @var overrides the singleton instance of this class. */
+    protected static $instance = null;
+
+    /**
+     * Returns an instance of the data source class that the cache can use for loading data using the other methods
+     * specified by this interface.
+     *
+     * @param cache_definition $definition
+     * @return object
+     */
+    public static function get_instance_for_cache(cache_definition $definition): overrides {
+        if (is_null(self::$instance)) {
+            self::$instance = new overrides();
+        }
+        return self::$instance;
+    }
+
+    /**
+     * Loads the data for the key provided ready formatted for caching.
+     *
+     * @param string|int $key The key to load.
+     * @return mixed What ever data should be returned, or false if it can't be loaded.
+     * @throws \coding_exception
+     */
+    public function load_for_cache($key) {
+        global $DB;
+
+        [$lessonid, $ug, $ugid] = explode('_', $key);
+        $lessonid = (int) $lessonid;
+
+        switch ($ug) {
+            case 'u':
+                $userid = (int) $ugid;
+                $override = $DB->get_record(
+                    'lesson_overrides',
+                    ['lessonid' => $lessonid, 'userid' => $userid],
+                    'available, deadline, timelimit, review, maxattempts, retake, password'
+                );
+                break;
+            case 'g':
+                $groupid = (int) $ugid;
+                $override = $DB->get_record(
+                    'lesson_overrides',
+                    ['lessonid' => $lessonid, 'groupid' => $groupid],
+                    'available, deadline, timelimit, review, maxattempts, retake, password'
+                );
+                break;
+            default:
+                throw new \coding_exception('Invalid cache key');
+        }
+
+        // Return null instead of false, because false will not be cached.
+        return $override ?: null;
+    }
+
+    /**
+     * Loads several keys for the cache.
+     *
+     * @param array $keys An array of keys each of which will be string|int.
+     * @return array An array of matching data items.
+     */
+    public function load_many_for_cache(array $keys) {
+        $results = [];
+
+        foreach ($keys as $key) {
+            $results[] = $this->load_for_cache($key);
+        }
+
+        return $results;
+    }
+}

mod/lesson/db/caches.php

@@ -0,0 +1,35 @@
+<?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/>.
+
+/**
+ * Defined caches used internally by the plugin.
+ *
+ * @package   mod_lesson
+ * @copyright 2021 Shamim Rezaie <shamim@moodle.com>
+ * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+declare(strict_types=1);
+
+defined('MOODLE_INTERNAL') || die();
+
+$definitions = [
+    'overrides' => [
+        'mode' => cache_store::MODE_APPLICATION,
+        'simplekeys' => true,
+        'datasource' => '\mod_lesson\cache\overrides',
+    ],
+];

mod/lesson/lang/en/lesson.php

@@ -83,6 +83,7 @@ $string['averagescore'] = 'Average score';
 $string['averagetime'] = 'Average time';
 $string['branch'] = 'Content';
 $string['branchtable'] = 'Content';
+$string['cachedef_overrides'] = 'User and group override information';
 $string['cancel'] = 'Cancel';
 $string['cannotfindanswer'] = 'Error: could not find answer';
 $string['cannotfindattempt'] = 'Error: could not find attempt';

mod/lesson/lib.php

@@ -924,23 +924,27 @@ function lesson_reset_userdata($data) {
         $status[] = array('component'=>$componentstr, 'item'=>get_string('deleteallattempts', 'lesson'), 'error'=>false);
     }
 
+    $purgeoverrides = false;
+
     // Remove user overrides.
     if (!empty($data->reset_lesson_user_overrides)) {
         $DB->delete_records_select('lesson_overrides',
                 'lessonid IN (SELECT id FROM {lesson} WHERE course = ?) AND userid IS NOT NULL', array($data->courseid));
         $status[] = array(
-        'component' => $componentstr,
-        'item' => get_string('useroverridesdeleted', 'lesson'),
-        'error' => false);
+            'component' => $componentstr,
+            'item' => get_string('useroverridesdeleted', 'lesson'),
+            'error' => false);
+        $purgeoverrides = true;
     }
     // Remove group overrides.
     if (!empty($data->reset_lesson_group_overrides)) {
         $DB->delete_records_select('lesson_overrides',
         'lessonid IN (SELECT id FROM {lesson} WHERE course = ?) AND groupid IS NOT NULL', array($data->courseid));
         $status[] = array(
-        'component' => $componentstr,
-        'item' => get_string('groupoverridesdeleted', 'lesson'),
-        'error' => false);
+            'component' => $componentstr,
+            'item' => get_string('groupoverridesdeleted', 'lesson'),
+            'error' => false);
+        $purgeoverrides = true;
     }
     /// updating dates - shift may be negative too
     if ($data->timeshift) {
@@ -953,12 +957,18 @@ function lesson_reset_userdata($data) {
                        WHERE lessonid IN (SELECT id FROM {lesson} WHERE course = ?)
                          AND deadline <> 0", array($data->timeshift, $data->courseid));
 
+        $purgeoverrides = true;
+
         // Any changes to the list of dates that needs to be rolled should be same during course restore and course reset.
         // See MDL-9367.
         shift_course_mod_dates('lesson', array('available', 'deadline'), $data->timeshift, $data->courseid);
         $status[] = array('component'=>$componentstr, 'item'=>get_string('datechanged'), 'error'=>false);
     }
 
+    if ($purgeoverrides) {
+        cache::make('mod_lesson', 'overrides')->purge();
+    }
+
     return $status;
 }
 

mod/lesson/locallib.php

@@ -657,14 +657,14 @@ function lesson_process_group_deleted_in_course($courseid, $groupid = null) {
     if ($groupid) {
         $params['groupid'] = $groupid;
         // We just update the group that was deleted.
-        $sql = "SELECT o.id, o.lessonid
+        $sql = "SELECT o.id, o.lessonid, o.groupid
                   FROM {lesson_overrides} o
                   JOIN {lesson} lesson ON lesson.id = o.lessonid
                  WHERE lesson.course = :courseid
                    AND o.groupid = :groupid";
     } else {
         // No groupid, we update all orphaned group overrides for all lessons in course.
-        $sql = "SELECT o.id, o.lessonid
+        $sql = "SELECT o.id, o.lessonid, o.groupid
                   FROM {lesson_overrides} o
                   JOIN {lesson} lesson ON lesson.id = o.lessonid
              LEFT JOIN {groups} grp ON grp.id = o.groupid
@@ -672,11 +672,15 @@ function lesson_process_group_deleted_in_course($courseid, $groupid = null) {
                    AND o.groupid IS NOT NULL
                    AND grp.id IS NULL";
     }
-    $records = $DB->get_records_sql_menu($sql, $params);
+    $records = $DB->get_records_sql($sql, $params);
     if (!$records) {
         return; // Nothing to do.
     }
     $DB->delete_records_list('lesson_overrides', 'id', array_keys($records));
+    $cache = cache::make('mod_lesson', 'overrides');
+    foreach ($records as $record) {
+        $cache->delete("{$record->lessonid}_g_{$record->groupid}");
+    }
 }
 
 /**
@@ -1740,8 +1744,10 @@ class lesson extends lesson_base {
                 'instance' => $this->properties->id);
         if (isset($override->userid)) {
             $conds['userid'] = $override->userid;
+            $cachekey = "{$cm->instance}_u_{$override->userid}";
         } else {
             $conds['groupid'] = $override->groupid;
+            $cachekey = "{$cm->instance}_g_{$override->groupid}";
         }
         $events = $DB->get_records('event', $conds);
         foreach ($events as $event) {
@@ -1750,6 +1756,7 @@ class lesson extends lesson_base {
         }
 
         $DB->delete_records('lesson_overrides', array('id' => $overrideid));
+        cache::make('mod_lesson', 'overrides')->delete($cachekey);
 
         // Set the common parameters for one of the events we will be triggering.
         $params = array(

mod/lesson/overrideedit.php

@@ -175,6 +175,8 @@ if ($mform->is_cancelled()) {
     if (!empty($override->id)) {
         $fromform->id = $override->id;
         $DB->update_record('lesson_overrides', $fromform);
+        $cachekey = $groupmode ? "{$fromform->lessonid}_g_{$fromform->groupid}" : "{$fromform->lessonid}_u_{$fromform->userid}";
+        cache::make('mod_lesson', 'overrides')->delete($cachekey);
 
         // Determine which override updated event to fire.
         $params['objectid'] = $override->id;
@@ -191,6 +193,8 @@ if ($mform->is_cancelled()) {
     } else {
         unset($fromform->id);
         $fromform->id = $DB->insert_record('lesson_overrides', $fromform);
+        $cachekey = $groupmode ? "{$fromform->lessonid}_g_{$fromform->groupid}" : "{$fromform->lessonid}_u_{$fromform->userid}";
+        cache::make('mod_lesson', 'overrides')->delete($cachekey);
 
         // Determine which override created event to fire.
         $params['objectid'] = $fromform->id;

mod/lesson/version.php

@@ -24,7 +24,7 @@
 
 defined('MOODLE_INTERNAL') || die();
 
-$plugin->version   = 2021052500;     // The current module version (Date: YYYYMMDDXX)
+$plugin->version   = 2021052501;     // The current module version (Date: YYYYMMDDXX)
 $plugin->requires  = 2021052500;    // Requires this Moodle version
 $plugin->component = 'mod_lesson'; // Full name of the plugin (used for diagnostics)
 $plugin->cron      = 0;