code: public function enqueue(CommandInterface $command)
      {
          $serializedCommand = serialize($command);
          $hash = md5($serializedCommand);
  
          if ($this->entryExists($hash)) {
              return;
          }
  
          $this->connection->insert($this->table, [
              'payload' => $serializedCommand,
              'hash' => $hash,
              'priority' => $command->getPriority(),
              'time' => (new DateTime('now'))->format(DATE_W3C),
              'status' => BacklogService::STATUS_OPEN,
          ]);
      }
docs: {@inheritdoc}