asp.net core 2.1 - ConfigureServices - How to build-up MQTT Server Options

Considering this code:

            var mqttServerOptions = new MqttServerOptionsBuilder()
                .WithDefaultEndpoint()
                .WithDefaultEndpointPort(9876)
                .WithConnectionValidator((ctx) =>
                {
                    var mediator = serviceProvider.GetService<IMediator>();
                    if (await mediator.Send(new AuthenticateTerminalForMqttCommand(ctx.Username, ctx.Password)))
                    {
                        logger.LogInformation("Client {0} has connected.", ctx.ClientId);
                        ctx.ReturnCode = MqttConnectReturnCode.ConnectionAccepted;
                        return;
                    }

                    logger.LogInformation("Client {0} has failed to authenticate.", ctx.ClientId);
                    ctx.ReturnCode = MqttConnectReturnCode.ConnectionRefusedBadUsernameOrPassword;
                })
                .Build();

We cannot pull anything into ConfigureServices() but the IServiceCollection object. So, with asp.net core 2.1, how do we provide a connection validator, among other items? When I look at the main Configure() method, although we can do app.UseMqttServer((mqttServer) => { ... custom code here ... });, it does not seem to let us assign a custom connection validator, as the property is marked as ReadOnly at this point.

Any suggestions/ideas for how to overcome this want/need would be great.

[JanEggers]

the problem is that the new pipeline does not yet support encrypted communication. (there is no tls connection middleware yet and using sslstream negates all the performance benefits)

so you should remove

        o.ListenAnyIP(9010, l => l.UseMqtt()); // mqtt pipeline
        services.AddMqttConnectionHandler();

and instead add the old tcp server adapter with

  services.AddMqttTcpServerAdapter();

[dealproc]

That’s pretty much what I wound up with. I now need to go through the bowels of the wire-up and see if its going to be possible or not to build an orleans backplane for this, so that we can host this within a web farm environment. I know others have advised against this, but I’m trying to keep our stack as compact as possible until we hit a critical mass.