Recursive directory iteration with PHP Filesystem API

I have a small stuff to do this morning related to php filesystem api, warming memcached for static files and php template to reduce I/O process overhead in front-end application

$dir = '/path/to/some/dir';
$flags = FilesystemIterator::SKIP_DOTS | FilesystemIterator::FOLLOW_SYMLINKS;
$iterator = new RecursiveDirectoryIterator($dir, $flags);
$result = array();
foreach ($iterator as $file) {
    $result[] = $file->getFilename();
}
print_r($result);

The result will be list of files and directories exist in `$dir`, somehow i need a recursive iterator, luckily php has it all, with small pimp I can have it, just before line where `$result` declaration, I add this line

$iterator = new RecursiveIteratorIterator($iterator, RecursiveIteratorIterator::SELF_FIRST);

bingo! now it running recursively, i need some filtering here since i only need files with `.txt` or `.html` files, currently it returned all files and directories exists in `$dir` so i created a new iterator filtering class as below

class FilterTxtHtml extends FilterIterator {
    public function accept() {
	$fileinfo = $this->getInnerIterator()->current();
	if (preg_match('/\.(txt|html)$/', $fileinfo)) {
	    return true;
	}
	return false;
    }   
}

save it somewhere, include it and put this line before `$result` declaration,

$iterator = new FilterTxtHtml($iterator);

final code as below:

$dir = '/path/to/some/dir';
$flags = FilesystemIterator::SKIP_DOTS | FilesystemIterator::FOLLOW_SYMLINKS;
$iterator = new RecursiveDirectoryIterator($dir, $flags);
$iterator = new RecursiveIteratorIterator($iterator, RecursiveIteratorIterator::SELF_FIRST);
$iterator = new FilterTxtHtml($iterator);
$result = array();
foreach ($iterator as $file) {
    $result[] = $file->getFilename();
}
print_r($result);

Easy enough.