/// <summary>
    /// Telemetry logging handler.
    /// </summary>
    public class TelemetryLoggingHandler : RequestHandler
    {
               /// <summary>
              /// Executes the request on CosmosDB and record telemetry.
             /// </summary>
             /// <param name="request">Request to execute.</param>
             /// <param name="cancellationToken">Cancellation token.</param>
             /// <returns>Task tracking operation.</returns>
             public override async Task<ResponseMessage> SendAsync(RequestMessage request, CancellationToken cancellationToken)
             {
                  ResponseMessage response = await base.SendAsync(request, cancellationToken).ConfigureAwait(false);
                  ServerSideCumulativeMetrics queryMetrics = response.Diagnostics?.GetQueryMetrics();
                  // queryMetrics is null here, even though Diagnostics isnt
             }
    }