SignalR Protocol

The Bielu.AspNetCore.AsyncApi.Extensions.Protocols.SignalR package adds support for documenting ASP.NET Core SignalR hubs using the custom signalr protocol.

Installation

dotnet add package Bielu.AspNetCore.AsyncApi.Extensions.Protocols.SignalR

Configuration

builder.Services.AddAsyncApi(options =>
{
    options.AddChannelBinding("chatHub", new SignalRChannelBinding
    {
        Hub = "/chatHub",
        Transports = { SignalRProtocol.Transports.WebSockets, SignalRProtocol.Transports.LongPolling },
        Protocols = { SignalRProtocol.HubProtocols.Json, SignalRProtocol.HubProtocols.MessagePack },
    });

    options.AddOperationBinding("sendMessage", new SignalROperationBinding
    {
        Target = "SendMessage",
        Direction = SignalRProtocol.Directions.ClientToServer,
        CallType = SignalRProtocol.CallTypes.Invocation,
    });
});

Hub Annotation

Annotate your hub class and its methods:

[AsyncApi]
[Channel("chatHub", BindingsRef = "chatHub")]
public class ChatHub : Hub
{
    [PublishOperation(typeof(ChatMessage), BindingsRef = "sendMessage")]
    public Task SendMessage(ChatMessage message) => Clients.All.SendAsync("ReceiveMessage", message);
}

Message Types

SignalR messages have specific types corresponding to the hub protocol:

Token	Wire id	Meaning
`invocation`	1	Client/server invokes a method
`streamItem`	2	A single item of a stream
`completion`	3	Result/error of an invocation
`streamInvocation`	4	Invokes a streaming method
`cancelInvocation`	5	Cancels a streaming invocation
`ping`	6	Keep-alive
`close`	7	Connection closing

Interactive Console