fn get():
    | path == "/" -> list:
        service.get_all()
    | path == "/{uuid}" -> Customer?:
        service.get(uuid)?
    | path == "/" && query.firstname -> Customer?:
        service.get_by_firstname(fname)?
    | path == "/" && query.last_name -> Customer?
        service.get_by_lastname(lname)?
    | 404

fn post(customer: Customer):
    service.add(customer)


fn put(customer: Customer):
    service.update(customer)