Вызов внешней функции из админки - Разработка расширений для Joomla 3.x

function getFile() {
	$referer = JRequest::getString('HTTP_REFERER', null, 'SERVER');
	$file = './media/com_vmtoxls/price.xlsx';
	$this->getXLS($file);
		
	if (JFile::exists($file)) {
		header("Content-Type: application/octet-stream");
		header("Accept-Ranges: bytes");
		header("Content-Length: ".filesize($file)); 
		header("Content-Disposition: attachment; filename=" . JFile::stripExt(JFile::getName($file)). '_' . date("d-m-Y"). '.' . JFile::getExt($file));  
		readfile($file);
			
	}
	else {
		JFactory::getApplication()->redirect($referer, JText::_('COM_VMTOXLS_NOTICE_FILE_NOT_EXISTS'), error);
	}
	return true;
}

public function update() {
	$router 	= 	JRouter::getInstance('site');
	$router	->	setMode(JROUTER_MODE_SEF);
	$update 	= 	new VMtoXLSModelGetXLS();
	$update 	-> 	getFile();
	$this->setRedirect(JRoute::_('index.php?option=com_vmtoxls&view=products', false));
}

if ($app->isAdmin()) {
	$uri = $router->build(JURI::root(). JRoute::_($link, true));
	$path = str_replace(array('http:/', '/administrator', '/index.php'), array('http://', '', ''), $uri->getPath());
	$uri->setPath($path);
	$url = JURI::root(). $uri->toString(array('path', 'query', 'fragment'));
}
else {
	$uri = JURI::root(). JRoute::_($link, true);
	$url = str_replace(array('//', 'http:/', '/index.php', '/component/vmtoxls'), array('/', 'http://', '', ''), $uri);
}