CREATE SCHEMA _sysinternal;

CREATE OR REPLACE FUNCTION _sysinternal.create_user_mapping(
    cluster_user_row cluster_user,
    node_row         node
)
    RETURNS VOID LANGUAGE PLPGSQL VOLATILE AS
$BODY$
BEGIN

    EXECUTE format(
        $$
            CREATE USER MAPPING FOR %1$I SERVER %2$I OPTIONS (user '%1$s', password '%3$s')
        $$,
        cluster_user_row.username, node_row.server_name, cluster_user_row.password);
END
$BODY$;

CREATE OR REPLACE FUNCTION _sysinternal.create_server(
    node_row         node
)
    RETURNS VOID LANGUAGE PLPGSQL VOLATILE AS
$BODY$
BEGIN
        EXECUTE format(
            $$
                CREATE SERVER %I FOREIGN DATA WRAPPER postgres_fdw OPTIONS(host '%s', dbname '%s') ;
            $$,
         node_row.server_name, node_row.hostname, node_row.database_name);
END
$BODY$;