Get isServer from NetworkMessage

How to identify if the message was sent by server or clinet from NetworkMessage?

I am creating a custom Spawning behaviour for the players and I want to identify a situation where I am spawning a player on a machine that is both server and client at the same time. Here is my code:

     public override void OnStartServer()
     {
         base.OnStartServer();
         NetworkServer.RegisterHandler(MsgType.AddPlayer, SpawnPlayer);
     }



     void SpawnPlayer(NetworkMessage netMsg)
     {
         AddPlayerMessage msg = netMsg.ReadMessage<AddPlayerMessage>();

         if (netMsg.conn.hostId < 0)
         {
             // Is this the right way to check if the message was sent by the server to himself?
         }
     }

As you can see from the code, right now I check if netMsg.conn.hostId < 0. Is this the right way to do this?