Exemple #1
0
 /**
  * Executes the following:
  *  - Attempts to update task object's row as processing
  *  - If successful, Begins a database transaction
  *  - Attempts to select that row for update
  *  - If successful, attempts to execute method callback defined in row, returning a result object
  *  - Updates the task object based on the resulting object
  *  - Commits the database transaction
  *
  * @param Reverb_ProcessQueue_Model_Task_Interface $processQueueTaskObject
  */
 public function processQueueTask(Reverb_ProcessQueue_Model_Task_Interface $processQueueTaskObject)
 {
     try {
         $able_to_lock_for_processing = $processQueueTaskObject->attemptUpdatingRowAsProcessing();
         if (!$able_to_lock_for_processing) {
             // Assume another thread of execution is already processing this task
             return;
         }
     } catch (Exception $e) {
         $error_message = $this->__(self::EXCEPTION_UPDATE_AS_PROCESSING, $processQueueTaskObject->getId(), $e->getMessage());
         $this->_logError($error_message);
         return;
     }
     // At this point, start transaction and lock row for update to ensure exclusive access
     $taskResourceSingleton = $processQueueTaskObject->getResource();
     $taskResourceSingleton->beginTransaction();
     try {
         $selected = $processQueueTaskObject->selectForUpdate();
         if (!$selected) {
             // Assume another thread has already locked this task object's row, although this shouldn't happen
             $taskResourceSingleton->rollBack();
             $error_message = $this->__(self::ERROR_FAILED_TO_SELECT_FOR_UPDATE, $processQueueTaskObject->getId());
             $this->_logError($error_message);
             return;
         }
     } catch (Exception $e) {
         $taskResourceSingleton->rollBack();
         $error_message = $this->__(self::EXCEPTION_SELECT_FOR_UPDATE, $processQueueTaskObject->getId(), $e->getMessage());
         $this->_logError($error_message);
         return;
     }
     try {
         $taskExecutionResult = $processQueueTaskObject->executeTask();
     } catch (Exception $e) {
         $taskResourceSingleton->rollBack();
         $error_message = $this->__(self::EXCEPTION_EXECUTING_TASK, $processQueueTaskObject->getId(), $e->getMessage());
         $processQueueTaskObject->setTaskAsErrored($error_message);
         $this->_logError($error_message);
         return;
     }
     try {
         $processQueueTaskObject->actOnTaskResult($taskExecutionResult);
     } catch (Exception $e) {
         // At this point, we would assume that the task has been performed successfully since executeTask() did not
         //  throw any exceptions. As such, log the exception but commit the transaction. Even if this leaves a row
         //  in the PROCESSING state, it's better than leaving parts of the database out of sync with external resources
         $error_message = $this->__(self::EXCEPTION_ACTING_ON_TASK_RESULT, $processQueueTaskObject->getId(), $e->getMessage());
         $this->_logError($error_message);
     }
     try {
         $taskResourceSingleton->commit();
     } catch (Exception $e) {
         // If an exception occurs here, rollback
         $taskResourceSingleton->rollback();
         $processQueueTaskObject->setTaskAsErrored();
         $error_message = $this->__(self::EXCEPTION_COMMITTING_TRANSACTION, $processQueueTaskObject->getId(), $e->getMessage());
         $this->_logError($error_message);
     }
 }
Exemple #2
0
 public function setExecutionStatusForTask($execution_status, Reverb_ProcessQueue_Model_Task_Interface $taskObject, $status_message = null)
 {
     $task_id = $taskObject->getId();
     if (empty($task_id)) {
         // TODO Some logging here
         return 0;
     }
     if ($taskObject->isStatusValid($execution_status)) {
         $update_bind_array = array('status' => $execution_status);
         if (!is_null($status_message)) {
             $update_bind_array['status_message'] = $status_message;
         }
         $task_id = $taskObject->getId();
         $where_conditions_array = array('task_id=?' => $task_id);
         $rows_updated = $this->_getWriteAdapter()->update($this->getMainTable(), $update_bind_array, $where_conditions_array);
         return $rows_updated;
     }
     // TODO Log error in this case
     return 0;
 }