camper/deploy/ensure_role_exists.sql

-- Deploy camper:ensure_role_exists to pg
-- requires: roles
-- requires: schema_camper
-- requires: company_user

begin;

set search_path to camper, public;

create or replace function ensure_role_exists() returns trigger as
$$
begin
	if not exists (select 1 from pg_roles where rolname = new.role) then
		raise foreign_key_violation using message = 'role not found: ' || new.role;
	end if;
	return new;
end;
$$
language plpgsql;

comment on function ensure_role_exists() is
'Makes sure that a role given to a user is a valid, existing role in the cluster.';

revoke execute on function ensure_role_exists() from public;

create trigger ensure_role_exists
after insert or update
on company_user
for each row
execute procedure ensure_role_exists();


commit;