Using rack middlewares directly from Rails actions

I have a Rack middleware that I want to embed in my Rails app. By embed, I mean injecting it into my application's layout, so that <%= yield %> contains the body of what the Rack app returns.

Here's my current solution:

def show
  result = MyRackApp.new.call(request.env)
  render :text => result[2].read, :status => result[0]
end

This is problematic, though, since result[2] does not always have a IO style read method, it might be a Rack::File for example.

So, how do I make a Rails controller render a [200, {}, some_io_object] type Rack response? Alternatively, can I do it开发者_JAVA技巧 the other way around with a Rack middleware that is able to render Rails layouts?

I'm using Rails 3.0.9.

If you want to use a rack application from Rails, you have to mount it from your router (routes.rb)

AppName::Application.routes.draw do 
  # Other routes

  mount MyRackApp => "/pathToReachIt"

  # root to: '...'
end

More info here