MDL-73293 core_task: Cleanup stale adhoc task metadata

lang/en/admin.php

@@ -1327,6 +1327,7 @@ $string['task_duration'] = 'Duration';
 $string['task_dbstats'] = 'Database';
 $string['task_result'] = 'Result';
 $string['tasktype'] = 'Type';
+$string['tasklockcleanuptask'] = 'Clean up ad hoc task metadata';
 $string['taskadmintitle'] = 'Tasks';
 $string['taskanalyticscleanup'] = 'Analytics cleanup';
 $string['taskautomatedbackup'] = 'Automated backups';

lib/classes/task/manager.php

@@ -1206,6 +1206,71 @@ class manager {
         return $DB->get_records_sql($sql, $params);
     }
 
+    /**
+     * Cleanup stale task metadata.
+     */
+    public static function cleanup_metadata() {
+        global $DB;
+
+        $cronlockfactory = \core\lock\lock_config::get_lock_factory('cron');
+        $runningtasks = self::get_running_tasks();
+
+        foreach ($runningtasks as $taskrecord) {
+            if ($taskrecord->timestarted > time() - HOURSECS) {
+                continue;
+            }
+
+            if ($taskrecord->type == 'adhoc') {
+                $lock = $cronlockfactory->get_lock('adhoc_' . $taskrecord->id, 0);
+            }
+
+            if ($taskrecord->type == 'scheduled') {
+                $lock = $cronlockfactory->get_lock($taskrecord->classname, 0);
+            }
+
+            // If we got this lock it means one of three things:
+            //
+            // 1. The task was stopped abnormally and the metadata was not cleaned up
+            // 2. This is the process running the cleanup task
+            // 3. We took so long getting to it in this loop that it did finish, and we now have the lock
+            //
+            // In the case of 1. we need to make the task as failed, in the case of 2. and 3. we do nothing.
+            if (!empty($lock)) {
+                if ($taskrecord->classname == "\\" . \core\task\task_lock_cleanup_task::class) {
+                    $lock->release();
+                    continue;
+                }
+
+                // We need to get the record again to verify whether or not we are dealing with case 3.
+                $taskrecord = $DB->get_record('task_' . $taskrecord->type, ['id' => $taskrecord->id]);
+
+                if ($taskrecord->type == 'scheduled') {
+                    // Empty timestarted indicates that this task finished (case 3) and was properly cleaned up.
+                    if (empty($taskrecord->timestarted)) {
+                        $lock->release();
+                        continue;
+                    }
+
+                    $task = self::scheduled_task_from_record($taskrecord);
+                    $task->set_lock($lock);
+                    self::scheduled_task_failed($task);
+                } else if ($taskrecord->type == 'adhoc') {
+                    // Ad hoc tasks are removed from the DB if they finish successfully.
+                    // If we can't re-get this task, that means it finished and was properly
+                    // cleaned up.
+                    if (!$taskrecord) {
+                        $lock->release();
+                        continue;
+                    }
+
+                    $task = self::adhoc_task_from_record($taskrecord);
+                    $task->set_lock($lock);
+                    self::adhoc_task_failed($task);
+                }
+            }
+        }
+    }
+
     /**
      * This function is used to indicate that any long running cron processes should exit at the
      * next opportunity and restart. This is because something (e.g. DB changes) has changed and

lib/classes/task/task_lock_cleanup_task.php

@@ -0,0 +1,53 @@
+<?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/>.
+
+/**
+ * Cleanup adhoc task metadata.
+ *
+ * @package    core
+ * @copyright  2022 Catalyst IT Australia Pty Ltd
+ * @author     Cameron Ball <cameron@cameron1729.xyz>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+namespace core\task;
+
+/**
+ * Adhoc task metadata cleanup task.
+ *
+ * @package    core
+ * @copyright  2022 Catalyst IT Australia Pty Ltd
+ * @author     Cameron Ball <cameron@cameron1729.xyz>
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class task_lock_cleanup_task extends scheduled_task {
+
+    /**
+     * Get a descriptive name for this task.
+     *
+     * @return string
+     */
+    public function get_name() {
+        return get_string('tasklockcleanuptask', 'admin');
+    }
+
+    /**
+     * Processes task.
+     */
+    public function execute() {
+        \core\task\manager::cleanup_metadata();
+    }
+}

lib/db/tasks.php

@@ -428,4 +428,13 @@ $tasks = array(
         'month' => '*',
         'dayofweek' => '*',
     ),
+    [
+        'classname' => 'core\task\task_lock_cleanup_task',
+        'blocking' => 0,
+        'minute' => 'R',
+        'hour' => '0',
+        'day' => '*',
+        'dayofweek' => '*',
+        'month' => '*'
+    ]
 );

version.php

@@ -29,7 +29,7 @@
 
 defined('MOODLE_INTERNAL') || die();
 
-$version  = 2022060300.00;              // YYYYMMDD      = weekly release date of this DEV branch.
+$version  = 2022060300.01;              // YYYYMMDD      = weekly release date of this DEV branch.
                                         //         RR    = release increments - 00 in DEV branches.
                                         //           .XX = incremental changes.
 $release  = '4.1dev (Build: 20220603)'; // Human-friendly version name