$:.push 'examples'; require 'helper' class Customer < RestModel property :login property :password property :description, if: proc {password == "abc"} end @root_with_description = Customer.from_source!({ login: 2000, password: "abc", description: "description"}).first inspect_rest_model(@root_with_description) @root_without_description = Customer.from_source!({ login: 2000, password: "abcd", description: "some text II"}).first inspect_rest_model(@root_without_description)