title: Signalr hub get caller client from controller
body: <p>How can i get the caller client (the client which is requesting the current action) from controller.</p>
  
  <p>something like the following:</p>
  
  <pre><code>  public class ChatController : EntityController
    {
        public void RegisterClientAsAvailable()
        {
            var hub=Microsoft.AspNet.SignalR.GlobalHost.ConnectionManager.GetHubContext&lt;ChatHub&gt;();
  
            var callingClient = hub.Clients.Caller;
  
  //And I want to pass additional parameters(which the client doesnt know about them) from `EntityController (base)` to this method:
  
            hub.RegisterClient(base.UserId,Session["something"],callingClient);
            //OR:
            hub.SayHelloToClient(base.UserId,Session["something"],callingClient);
        }
    }
  </code></pre>