api.cs

[WebSocketAuth]
public class TXWebSocketController : ApiController {
    public HttpResponseMessage Get() {
     if (HttpContext.Current.IsWebSocketRequest) {
        var wsHandler = new WebSocketHandler();
        wsHandler.ProcessRequest(HttpContext.Current);
        return new HttpResponseMessage(HttpStatusCode.SwitchingProtocols);
     }
     return new HttpResponseMessage(HttpStatusCode.OK);
  }
}