Soenneker.SignalR.Web.Client 4.0.808

Soenneker.SignalR.Web.Client

A SignalR client wrapper that retries initial connections, recovers closed connections, and exposes callbacks for restoring application state after a connection returns.

Installation

dotnet add package Soenneker.SignalR.Web.Client

Usage

using Microsoft.AspNetCore.Http.Connections;
using Soenneker.SignalR.Web.Client;
using Soenneker.SignalR.Web.Client.Options;

var options = new SignalRWebClientOptions
{
    HubUrl = "https://api.example.com/hubs/updates",
    AccessTokenProvider = () => Task.FromResult(accessToken),
    TransportType = HttpTransportType.WebSockets,
    ConnectionRestored = async context =>
    {
        // Reload authoritative state after the initial connection or a reconnect.
        await SynchronizeAsync(context.IsReconnect);
    },
    RetriesExhausted = () => NotifyConnectionFailure()
};

await using var client = new SignalRWebClient(options);

client.Connection.On<OrderUpdated>("OrderUpdated", update =>
{
    Apply(update);
});

await client.StartConnection(cancellationToken);
await client.Connection.InvokeAsync("Subscribe", accountId, cancellationToken);

The wrapper owns its HubConnection; dispose the wrapper when the connection is no longer needed. Use Connection to register handlers with On(...) and call hub methods with InvokeAsync(...).

Reconnection behavior

Each connection cycle retries a failed start up to MaxRetryAttempts times using exponential backoff. After an unexpected close, ReconnectIndefinitely starts another cycle after InitialRetryDelay; set it to false to stop after the first exhausted cycle. RetriesExhausted is invoked when recovery stops, and ConnectionRestored runs after both an initial connection and a successful recovery.

Enable StatefulReconnect only when the server supports it. StatefulReconnectBufferSize controls the client-side buffered message bytes used by that mode.

Call StopConnection for an intentional disconnect. This suppresses closed-connection recovery until StartConnection is called again.

Authentication and headers

AccessTokenProvider is evaluated by SignalR when it needs a bearer token. Static request headers can be supplied through Headers; avoid placing secrets in headers that may be sent by transports or intermediaries you do not control.