public static IApplicationBuilder MapWebSocketManager(this IApplicationBuilder app,
                                                       PathString path,
                                                       WebSocketHandler handler)
 {
     return(app.Map(path, (_app) => _app.UseMiddleware <WebSocketManagerMiddleware>(handler)));
 }
 public WebSocketManagerMiddleware(RequestDelegate next,
                                   WebSocketHandler webSocketHandler)
 {
     _next             = next;
     _webSocketHandler = webSocketHandler;
 }