Dragonfly and RefineryCMS resources authentification

[Boris]

Hi,

I would like to control resource access based on Devise user
authentification. I am aware of Dragonfly's option to override
responses:

app.configure do |c|
c.server.before_serve do |job, env|
throw :halt, [200, {'Content-type' => 'text/plain'}, ['hello']]
end
end

However, I am unsure how to use this hook in order to apply a session-
based access control.

I have tried the following paths:

1. Getting hold of the current user within the before_serve callback
(env, Thread), without success.
2. Putting a new rack middleware in front of the Dragonfly rack. This
seemed unfavorable as it affected any http request and thus the
overall performance of the application. Further, I have not managed to
disable caching of Dragonfly assets which rendered the authentication
rack pointless.
3. I added a new route which handled the authentication in the
controller before redirecting to the original Dragonfly resource.
However, I could not prevent the original route from being still
publicly accessible which again rendered the authentication step
useless.

I am a little desperate with this would appreciate any useful hint in
this matter.

Thanks,
Boris