public function execute()
    {
        if (!defined('ENABLE_SHELL_PLUGIN') || !ENABLE_SHELL_PLUGIN) {
            throw new \Exception(Lang::get('shell_not_enabled'));
        }

        $success = true;

        foreach ($this->commands as $command) {
            $command = $this->phpci->interpolate($command);

            if (!$this->phpci->executeCommand($command)) {
                $success = false;
            }
        }

        return $success;
    }