REPP: Move nameservers endpoint to Rails API format

app/controllers/repp/v1/registrar/nameservers_controller.rb

@@ -0,0 +1,40 @@
+module Repp
+  module V1
+    module Registrar
+      class NameserversController < BaseController
+        before_action :verify_nameserver_existance, only: %i[update]
+
+        def update
+          domains = current_user.registrar
+                                .replace_nameservers(hostname, hostname_params[:data][:attributes])
+
+          render_success(data: data_format_for_success(domains))
+        rescue ActiveRecord::RecordInvalid => e
+          handle_errors(e.record)
+        end
+
+        private
+
+        def data_format_for_success(affected_domains)
+          { type: 'nameserver', id: params[:data][:attributes][:hostname],
+            attributes: params[:data][:attributes], affected_domains: affected_domains }
+        end
+
+        def hostname_params
+          params.require(:data).require(%i[type id])
+          params.require(:data).require(:attributes).require(%i[hostname ipv4 ipv6])
+
+          params.permit(data: [:type, :id, attributes: [:hostname, ipv4: [], ipv6: []]])
+        end
+
+        def hostname
+          hostname_params[:data][:id]
+        end
+
+        def verify_nameserver_existance
+          current_user.registrar.nameservers.find_by!(hostname: hostname)
+        end
+      end
+    end
+  end
+end