request_uri

# File actionpack/lib/action_controller/request.rb, line 140
    def request_uri
      if uri = @env['REQUEST_URI']
        # Remove domain, which webrick puts into the request_uri.
        (%r{^\w+\://[^/]+(/.*|$)$} =~ uri) ? $1 : uri
      else
        # Construct IIS missing REQUEST_URI from SCRIPT_NAME and PATH_INFO.
        script_filename = @env['SCRIPT_NAME'].to_s.match(%r{[^/]+$})
        uri = @env['PATH_INFO']
        uri = uri.sub(/#{script_filename}\//, '') unless script_filename.nil?
        unless (env_qs = @env['QUERY_STRING']).nil? || env_qs.empty?
          uri << '?' << env_qs
        end
        @env['REQUEST_URI'] = uri
      end
    end