SignalR and MiddleWare

CustomMiddleWare.cs

public class CustomMiddleWare : OwinMiddleware
{
	public CustomMiddleWare(OwinMiddleware next)
            : base(next)  { }
        
        public override Task Invoke(IOwinContext context)
        {
            try
            {
                if (context.Request.QueryString.HasValue)
                {
                	// access the query with context.Request.Query.Get
                	// set a custom user with context.Request.User = new CustomUser()
                }
            }
            catch (Exception ex)
            {
                // handle
            }
           
            return this.Next.Invoke(context);
        }
}

Startup.cs

class Startup
    {
        public void Configuration(IAppBuilder app)
        {
            app.Use(typeof(CustomMiddleWare));
            app.MapSignalR();
        }
    }