start_driver

# File actioncable/lib/action_cable/connection/client_socket.rb, line 57
      def start_driver
        return if @driver.nil? || @driver_started
        @stream.hijack_rack_socket

        if callback = @env["async.callback"]
          callback.call([101, {}, @stream])
        end

        @driver_started = true
        @driver.start
      end