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The DDK provides for mechanisms to define one’s own signalR hubs that are then discovered and bundled into the framework.

 

This can be done by the following:

 

1. Install signalR Nuget package.

 

dotnet add package Microsoft.AspNetCore.SignalR

 

To create a signalR hub simply implement the Hub class from Microsoft.AspNetCore.SignalR library.

 

using Microsoft.AspNetCore.SignalR;
 
namespace FrameworkTest
{
  public class LiveUpdateHub : Hub
   {
      public async Task SendUpdate(string message)
       {
           await Clients.All.SendAsync("ReceiveUpdate", message);
       }
   }
}

 

The hub will be discovered at runtime and configured into the application’s life-cycle and be available for use.

The hub url will automatically be the same as the hub name.

 

2. Retrieving a hub.

 

To retrieve a hub from the framework, use the static GetHub<T> method on the static HubsLocator class.

This method should be called after successful initialization and completion of BncsFramework .

 

using BNCS.Core.DriverFramework;
using BNCS.Core.DriverFramework.SignalR;
using Microsoft.AspNetCore.SignalR;
 
internal class Program
{
  private static IHubContext<LiveUpdateHub> hub;
   
  static void Main(string[] args)
  {
     BncsFramework.Init();
     
      //After succesful initialization of BncsFramework, retrieve the specific hub
     hub = HubsLocator.GetHub<LiveUpdateHub>();
     
 
  }
 
  //Event occured that requires notifying the connected clients
    private static void TestDriver_StatusChangedEvent(object? sender, string e)
    {
        //call methods on the hub to notify connected clients
        hub!.Clients.All.SendAsync("broadcast message!", $"{e}");
    }
}

 

3. Register the external assembly.

 

Automatic hub discovery requires the hubs to be in the assembly configured at BncsFramework.Init ()

 

namespace FrameworkTest
{
  BncsFramework.Init(...
  //the hubs should be in a namespace within the assembly injected here
   externalAssembly: typeof(Program).Assembly,
   );
}

 

Framework Behavior Notes:

 

Automatic hub discovery requires classes to:

 

Inherit from Microsoft.AspNetCore.SignalR.Hub

Endpoint url naming convention: /hubname (same name as class name)