Sinatra access-control-allow-origin for sinatra public folder

Question

How do I set up Sinatra so that static files in the public folder are returned with the response Access-Control-Allow-Origin = \"*\" ?

Answer 1

I did this on a server side, my file was called server.rb:

before do
   content_type :json    
   headers 'Access-Control-Allow-Origin' => '*', 
            'Access-Control-Allow-Methods' => ['OPTIONS', 'GET', 'POST']  
end