SignalR Skill

ASP.NET Core SignalR implementation for real-time client-server communication. Sorcha uses two hubs: ActionsHub (Blueprint Service) for workflow notifications and RegisterHub (Register Service) for ledger events. Both use group-based broadcasting with JWT authentication via query parameters.

Quick Start

Hub Implementation

// Strongly-typed hub with client interface public class RegisterHub : Hub<IRegisterHubClient> { public async Task SubscribeToRegister(string registerId) { await Groups.AddToGroupAsync(Context.ConnectionId, $"register:{registerId}"); } }

public interface IRegisterHubClient { Task RegisterCreated(string registerId, string name); Task TransactionConfirmed(string registerId, string transactionId); }

Sending from Services

public class NotificationService { private readonly IHubContext<ActionsHub> _hubContext;

public async Task NotifyActionConfirmedAsync(ActionNotification notification, CancellationToken ct)
{
    await _hubContext.Clients
        .Group($"wallet:{notification.WalletAddress}")
        .SendAsync("ActionConfirmed", notification, ct);
}

}

Client Connection (Testing)

var connection = new HubConnectionBuilder() .WithUrl($"{baseUrl}/actionshub?access_token={jwt}") .Build();

connection.On<ActionNotification>("ActionConfirmed", notification => { /* handle */ }); await connection.StartAsync(); await connection.InvokeAsync("SubscribeToWallet", walletAddress);

Key Concepts

Concept Usage Example

Groups Route messages to subscribers wallet:{address} , register:{id} , tenant:{id}

Typed Hubs Compile-time safety Hub<IRegisterHubClient>

IHubContext Send from services Inject IHubContext<THub>

JWT Auth Query parameter auth ?access_token={jwt}

Common Patterns

Service Abstraction Over Hub

When: Decoupling business logic from SignalR implementation

// Interface in Services/Interfaces/ public interface INotificationService { Task NotifyActionAvailableAsync(ActionNotification notification, CancellationToken ct = default); }

// Register in DI builder.Services.AddScoped<INotificationService, NotificationService>();

Hub Registration in Program.cs

builder.Services.AddSignalR();

// Map after authentication middleware app.MapHub<ActionsHub>("/actionshub"); app.MapHub<RegisterHub>("/hubs/register");

See Also

• patterns - Hub patterns, group routing, typed clients

• workflows - Testing, scaling, authentication setup

Related Skills

• aspire - Service orchestration and configuration

• jwt - Authentication token setup for hub connections

• redis - Backplane configuration for scaling

• xunit - Integration testing patterns

• fluent-assertions - Test assertions for hub tests

Documentation Resources

Fetch latest SignalR documentation with Context7.

How to use Context7:

• Use mcp__context7__resolve-library-id to search for "signalr aspnetcore"

• Prefer website documentation (IDs starting with /websites/ ) over source code

• Query with mcp__context7__query-docs using the resolved library ID

Library ID: /websites/learn_microsoft_en-us_aspnet_core (ASP.NET Core docs including SignalR)

Recommended Queries:

• "SignalR hub groups authentication"

• "SignalR Redis backplane scaling"

• "SignalR strongly typed hubs"