How to send files to logz.io kibana and have properties accepted as fields

KibanaClient.cs

using System;
using System.Net;
using RestSharp;

namespace Alexw.ParkingAvailable
{
    public class KibanaClient
    {
        private readonly IRestClient _client;
        private readonly string _token;

        public KibanaClient(IRestClient client, string token)
        {
            _client = client;
            _token = token;
        }

        public void Upload<T>(params T[] objectsToUpload)
        {
            if(objectsToUpload == null)
                throw new ArgumentOutOfRangeException("objectsToUpload");

            var relativeUrl = "";

            if (!string.IsNullOrEmpty(_token))
            {
                relativeUrl += relativeUrl.Contains("?") ? "&" : "?";
                relativeUrl += "token=" + _token;
            }

            foreach (var element in objectsToUpload)
            {
                var request = new RestRequest(relativeUrl);
                request.AddJsonBody(element);

                var response = _client.Post(request);
                if (response.StatusCode != HttpStatusCode.OK)
                {
                    throw new Exception(response.ErrorMessage);
                }
            }
        }
    }
}