rack.rb

module Rack
  class Request
    def scheme
      if @env['HTTPS'] == 'on'
        'https'
      elsif @env['HTTP_X_FORWARDED_SSL'] == 'on'
        'https'
      elsif @env['HTTP_X_FORWARDED_PROTO']
        @env['HTTP_X_FORWARDED_PROTO'].split(',')[0]
      else
        @env["rack.url_scheme"]
      end
    end

    def ssl?
      scheme == 'https'
    end

    def host_with_port
      if forwarded = @env["HTTP_X_FORWARDED_HOST"]
        forwarded.split(/,\s?/).last
      else
        @env['HTTP_HOST'] || "#{@env['SERVER_NAME'] || @env['SERVER_ADDR']}:#{@env['SERVER_PORT']}"
      end
    end

    def port
      if port = host_with_port.split(/:/)[1]
        port.to_i
      elsif port = @env['HTTP_X_FORWARDED_PORT']
        port.to_i
      elsif ssl?
        443
      elsif @env.has_key?("HTTP_X_FORWARDED_HOST")
        80
      else
        @env["SERVER_PORT"].to_i
      end
    end
  end
end

rack/rack#287