instance method restart

# File actioncable/lib/action_cable/server/base.rb, line 74
      def restart
        each_connection do |connection|
          connection.close(reason: ActionCable::INTERNAL[:disconnect_reasons][:server_restart])
        end

        @mutex.synchronize do
          # Drop the closed connections. remove_connection normally runs on the
          # worker pool, which we halt below, so the entries would otherwise leak.
          connections_map.clear

          # Shutdown the heartbeat timer
          @heartbeat_timer.shutdown if @heartbeat_timer
          @heartbeat_timer = nil

          # Shutdown the worker pool
          @worker_pool.halt if @worker_pool
          @worker_pool = nil

          # Shutdown the executor
          @executor.shutdown if @executor
          @executor = nil

          # Shutdown the pub/sub adapter
          @pubsub.shutdown if @pubsub
          @pubsub = nil
        end
      end