public HttpResponseMessage AddParticipation(HttpRequestMessage request, [FromBody] Participation participation)
        {
            return(Execute(request, () =>
            {
                var client = _participationService.AddParticipation(participation);

                return request.CreateResponse(HttpStatusCode.OK, client);
            }));
        }
 public IActionResult AddParticipation(ParticipationRequest request)
 {
     try
     {
         _participationService.AddParticipation(UserId, request.ActivityId);
         _hubNotifier.NotifyAboutNewParticipationRequest(request.ActivityId, UserId);
         return(Ok());
     }
     catch (ArgumentException ex)
     {
         return(BadRequest(ex.Message));
     }
 }