Calling SignalR hub clients from elsewhere in system
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
Solution 1:
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.
Solution 2:
Hub.GetClients has disappeared in version 0.4.0.
From the wiki you can now use:
IConnectionManager connectionManager = AspNetHost.DependencyResolver.Resolve<IConnectionManager>();
dynamic clients = connectionManager.GetClients<MyHub>();
Solution 3:
You can easily use a hub by following this 2 step-
-
Instantiating by dependency injection like this-
public class ClassName { ........ ........ private IHubContext _hub; public BulletinSenderController(IConnectionManager connectionManager) { _hub = connectionManager.GetHubContext<McpHub>(); ........ ........ } ............ ............ }
2.Using the hub
object like this-
_hub.Clients.All.onBulletinSent(bulletinToSend);
More can be found here.
Example code can be found in this git repo.