/**
* Executes the current command.
*
* @param InputInterface $input An InputInterface instance
* @param OutputInterface $output An OutputInterface instance
*
* @return null|int null or 0 if everything went fine, or an error code
*/
protected function execute(InputInterface $input, OutputInterface $output)
{
$config = $this->assetic->getConfiguration();
$config->setBuildOnRequest(true);
$this->assetic->build();
$this->assetic->getAssetWriter()->writeManagerAssets($this->assetic->getAssetManager());
}