fancier way of creating type

tools/captiveportal.pgsql

@@ -1,7 +1,15 @@
-create type inet_protocol as enum ('tcp', 'udp');
+-- create type inet_protocol as enum ('tcp', 'udp');
+
+DO $$
+BEGIN
+    IF NOT EXISTS (SELECT 1 FROM pg_type WHERE typname = 'inet_protocol') THEN
+        CREATE TYPE inet_protocol AS enum ('tcp', 'udp');
+    END IF;
+    --more types here...
+END$$;
 
 create table if not exists client (
- client_id uuid NOT NULL primary key unique,
+ client_id uuid NOT NULL unique,
  created timestamp NOT NULL,
  ip_address inet NOT NULL,
  protocol inet_protocol NOT NULL,