How do I set up advanced CORS in my Rack application?

How do I set up advanced CORS in my Rack application?

To set up advanced CORS in your Rack application, you can use the 'rack-cors' gem. First, add it to your Gemfile.

What configurations do I need to add for it to work?

You need to configure the middleware in your Rack application. Here's a basic example:

use Rack::Cors do
  allow do
    origins '*'  # Change this to your allowed origins
    resource '*', headers: :any, methods: [:get, :post, :options]
  end
end

Can I restrict CORS to specific domains?

Yes, you can specify allowed origins by replacing '*' with the specific domains you want to allow, like 'https://example.com'.

What about preflight requests?

Preflight requests are automatically handled by the 'rack-cors' gem. Just ensure your server responds to OPTIONS requests.