/* checking types: */
SELECT t.typname FROM pg_type t join pg_namespace ns ON t.typnamespace=ns.oid WHERE ns.nspname=current_schema() AND t.typname='wwwfdwoptions';
 typname 
---------
(0 rows)

SELECT t.typname FROM pg_type t join pg_namespace ns ON t.typnamespace=ns.oid WHERE ns.nspname=current_schema() AND t.typname='wwwfdwpostparameters';
 typname 
---------
(0 rows)

/* check exension: */
CREATE EXTENSION www_fdw;
CREATE SERVER www_fdw_server FOREIGN DATA WRAPPER www_fdw;
CREATE USER MAPPING FOR current_user SERVER www_fdw_server;
DROP EXTENSION www_fdw CASCADE;
NOTICE:  drop cascades to 2 other objects
DETAIL:  drop cascades to server www_fdw_server
drop cascades to user mapping for postgres