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Diffstat (limited to 'classes/Scheduler.php')
| -rw-r--r-- | classes/Scheduler.php | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/classes/Scheduler.php b/classes/Scheduler.php new file mode 100644 index 000000000..f0ca38303 --- /dev/null +++ b/classes/Scheduler.php @@ -0,0 +1,124 @@ +<?php +class Scheduler { + private static ?Scheduler $instance = null; + + const TASK_RC_EXCEPTION = -100; + + /** @var array<string, mixed> */ + private array $scheduled_tasks = []; + + public static function getInstance(): Scheduler { + if (self::$instance == null) + self::$instance = new self(); + + return self::$instance; + } + + /** + * Adds a backend scheduled task which will be executed by updater (if due) during housekeeping. + * + * The granularity is not strictly guaranteed, housekeeping is invoked several times per hour + * depending on how fast feed batch was processed, but no more than once per minute. + * + * Tasks do not run in user context. Task names may not overlap. Plugins should register tasks + * via PluginHost methods (to be implemented later). + * + * Tasks should return an integer value (return code) which is stored in the database, a value of + * 0 is considered successful. + * + * @param string $task_name unique name for this task, plugins should prefix this with plugin name + * @param string $cron_expression schedule for this task in cron format + * @param Closure $callback task code that gets executed + */ + function add_scheduled_task(string $task_name, string $cron_expression, Closure $callback) : bool { + $task_name = strtolower($task_name); + + if (isset($this->scheduled_tasks[$task_name])) { + user_error("Attempted to override already registered scheduled task $task_name", E_USER_WARNING); + return false; + } else { + try { + $cron = new Cron\CronExpression($cron_expression); + } catch (InvalidArgumentException $e) { + user_error("Attempt to register scheduled task $task_name failed: " . $e->getMessage(), E_USER_WARNING); + return false; + } + + $this->scheduled_tasks[$task_name] = [ + "cron" => $cron, + "callback" => $callback, + ]; + return true; + } + } + + /** + * Execute scheduled tasks which are due to run and record last run timestamps. + */ + function run_due_tasks() : void { + Debug::log('Processing all scheduled tasks...'); + + $tasks_succeeded = 0; + $tasks_failed = 0; + + foreach ($this->scheduled_tasks as $task_name => $task) { + $task_record = ORM::for_table('ttrss_scheduled_tasks') + ->where('task_name', $task_name) + ->find_one(); + + if ($task_record) + $last_run = $task_record->last_run; + else + $last_run = '1970-01-01 00:00'; + + // because we don't schedule tasks every minute, we assume that task is due if its + // next estimated run based on previous timestamp is in the past + if ($task['cron']->getNextRunDate($last_run)->getTimestamp() - time() < 0) { + Debug::log("Task $task_name is due, executing..."); + + $task_started = time(); + + try { + $rc = (int) $task['callback'](); + } catch (Exception $e) { + user_error("Scheduled task $task_name failed with exception: " . $e->getMessage(), E_USER_WARNING); + + $rc = self::TASK_RC_EXCEPTION; + } + + $task_duration = time() - $task_started; + + if ($rc === 0) { + ++$tasks_succeeded; + Debug::log("Task $task_name has finished in $task_duration seconds."); + } else { + $tasks_failed++; + Debug::log("Task $task_name has failed with RC: $rc after $task_duration seconds."); + } + + if ($task_record) { + $task_record->last_run = Db::NOW(); + $task_record->last_duration = $task_duration; + $task_record->last_rc = $rc; + + $task_record->save(); + } else { + $task_record = ORM::for_table('ttrss_scheduled_tasks')->create(); + + $task_record->set([ + 'task_name' => $task_name, + 'last_duration' => $task_duration, + 'last_rc' => $rc, + 'last_run' => Db::NOW(), + ]); + + $task_record->save(); + } + } + } + + Debug::log("Finished with $tasks_succeeded tasks succeeded and $tasks_failed tasks failed."); + } + + // TODO implement some sort of automatic cleanup for orphan task execution records +}
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