Calling SignalR hub clients from elsewhere in system

Jordan Wallwork picture Jordan Wallwork · Oct 3, 2011 · Viewed 63.4k times · Source

I've set up a SignalR hub to communicate between the server and client. The hub server side code is stored in a class called Hooking.cs. What I want is to be able to call a method defined in Hooking.cs to allow me to broadcast messages to any connected clients from anywhere in my application. It seems that a new instance of Hooking.cs is created for every client/server call, so I had hoped that I would be able to use something like

var hooking = new Hooking();
hooking.Test();

with the method Test() defined in Hooking.cs such as

public static void Test() {
    Clients.test()
}

and with a the client side javascript

var hooking = $.connection.hooking;
hooking.test = function() { alert("test worked"); };
$.connection.hub.start()

Unfortunately it isn't that simple, as Clients is not static, so not accessible from a static method.

Looking through the SignalR source code I came across a method that looked promising, Hubs.Invoke(string hubName, string method, params object[] args), so I would hope I could use something such as Hubs.Invoke("Hooking", "Test") but I can't make it work.

Any help with this would be hugely appreciated

Answer

Paolo Moretti picture Paolo Moretti · Jun 6, 2012

This is the correct way for SignalR 2.x:

var context = GlobalHost.ConnectionManager.GetHubContext<MyHub>();
context.Clients.All.addMessage(message);

Basically, you can use the dependency resolver for the current host to resolve the IConnectionManager interface which allows you to get ahold of the context object for a hub.

Further information can be found in the official documentation.