private function getRootFilter(RequestInterface $request)
    {
        $filter = null;

        if ($request->getFilter()) {
            $filter = $this->queryBuilder->buildQuery($request->getFilter());
        }

        return $filter;
    }
private function getRootFilter(RequestInterface $request)
    {
        $filter = null;

        if ($request->getFilter()) {
            $filter = $this->queryBuilder->buildQuery($request->getFilter());
        }

        return $filter;
    }
private function getRootFilter ( RequestInterface $ request ) { $ filter = null ; if ( $ request -> getFilter ( ) ) { $ filter = $ this -> queryBuilder -> buildQuery ( $ request -> getFilter ( ) ) ; } return $ filter ; }
Extract and build the root filter of the search request.

@param RequestInterface $request Search request.

@return array
Extract and build the root filter of the search request .