get_remote_url example

        // Transient per URL.         $cache_key = $this->build_cache_key_for_url( $url );

        // Attempt to retrieve cached response.         $cached_response = $this->get_cache( $cache_key );

        if ( ! empty( $cached_response ) ) {
            $remote_url_response = $cached_response;
        } else {
            $remote_url_response = $this->get_remote_url( $url );

            // Exit if we don't have a valid body or it's empty.             if ( is_wp_error( $remote_url_response ) || empty( $remote_url_response ) ) {
                return $remote_url_response;
            }

            // Cache the valid response.             $this->set_cache( $cache_key, $remote_url_response );
        }

        $html_head     = $this->get_document_head( $remote_url_response );