Rails 3, How to get Application URL inside routes

Question

I thkink this is a easy question, but I didn't find the solution. In Rails, How can I get my application URL inside routes?

Something like:

get '/foo', to: redirect("http://whatheverurl.com/?bar=#{MY_APPLICATION_URL}")

Answer 1

  match '/foo', :to => redirect { |params, request|
    "http://whatheverurl.com/?bar=#{request.env['HTTP_HOST']}"
  }

Answer 2

You could do something like this:

  match "/web_site", :to => proc { |env|
    [301, { 
      'Location' => "http://www.greenviewdata.com?from=#{env['HTTP_HOST']}" 
    }, ["Go here instead: http://www.greenviewdata.com?from=#{env['HTTP_HOST']}"]]
  }