*
	 * @param WP_REST_Request $request Full details about the request.
	 * @return WP_Error|WP_REST_Response
	 */
	public function get_content_items( $request ) {

		$this->content_controller->set_parent_id( $request['id'] );
		$result = $this->content_controller->get_items( $request );

		// Specs require 404 when no section's lessons are found.
		if ( ! is_wp_error( $result ) && empty( $result->data ) ) {
			return llms_rest_not_found_error();
		}