Handling CORS in Rails app

Ruby cors

module Userapi
  class Application < Rails::Application
    
    #...
    
    #Rails 3/4
    config.middleware.insert_before 0, "Rack::Cors" do
      allow do
        origins '*'
        resource '*', :headers => :any, :methods => [:get, :post, :options]
      end
    end
    
    #Rails 5/6
    config.middleware.insert_before 0, Rack::Cors do
      allow do
        origins '*'
        resource '*', :headers => :any, :methods => [:get, :post, :options]
      end
    end

  end
end