RSpec request spec post an empty array

I am current developing an API endpoint in rails. I want to be sure the endpoint response with the correct error status if the data I need is invalid. I need an array of ids. One of the invalid values is an empty array. Valid { vendor_district_ids: [2, 4, 5, 6]} Invalid { vendor_district_ids: []} Request Spec with RSpec So I want to have a request spec to control my behaviour. require 'rails_helpe