Rails CORS (Ruby on Rails Cross-Origin Resource Sharing)

application.rb

module Carservice
  class Application < Rails::Application
    config.middleware.insert_before 0, "Rack::Cors" do
      allow do
        origins '*'
        resource '*', headers: :any, methods: [:get, :post, :options]
      end
    end

Gemfile

gem 'rack-cors'