private void HandleTimeSyncResponses(IBeaconSendingContext context, TimeSyncRequestsResponse response)
{
// time sync requests were *not* successful
// -OR-
// time sync requests are not supported by the server (e.g. AppMon)
// -> use 0 as cluster time offset
if (response.timeSyncOffsets.Count < TIME_SYNC_REQUESTS)
{
HandleErroneousTimeSyncRequest(context, response.response);
return;
}
//sanity check to catch case with div/0
var calculatedOffset = ComputeClusterTimeOffset(response.timeSyncOffsets);
if (calculatedOffset < 0)
{
return;
}
// initialize time provider with cluster time offset
context.InitializeTimeSync(calculatedOffset, true);
// update the last sync time
context.LastTimeSyncTime = context.CurrentTimestamp;
// perform transition to next state
SetNextState(context);
}
private TimeSyncRequestsResponse ExecuteTimeSyncRequests(IBeaconSendingContext context)
{
var response = new TimeSyncRequestsResponse();
var retry = 0;
var sleepTimeInMillis = INITIAL_RETRY_SLEEP_TIME_MILLISECONDS;
// no check for shutdown here, time sync has to be completed
while (response.timeSyncOffsets.Count < TIME_SYNC_REQUESTS && !context.IsShutdownRequested)
{
// doExecute time-sync request and take timestamps
var requestSendTime = context.CurrentTimestamp;
var timeSyncResponse = context.GetHTTPClient().SendTimeSyncRequest();
var responseReceiveTime = context.CurrentTimestamp;
if (BeaconSendingResponseUtil.IsSuccessfulResponse(timeSyncResponse))
{
var requestReceiveTime = timeSyncResponse.RequestReceiveTime;
var responseSendTime = timeSyncResponse.ResponseSendTime;
// check both timestamps for being > 0
if ((requestReceiveTime > 0) && (responseSendTime > 0))
{
// if yes -> continue time-sync
var offset = ((requestReceiveTime - requestSendTime) + (responseSendTime - responseReceiveTime)) / 2;
response.timeSyncOffsets.Add(offset);
retry = 0; // on successful response reset the retry count & initial sleep time
sleepTimeInMillis = INITIAL_RETRY_SLEEP_TIME_MILLISECONDS;
}
else
{
// if no -> stop time sync, it's not supported
context.DisableTimeSyncSupport();
break;
}
}
else if (retry >= TIME_SYNC_RETRY_COUNT)
{
// retry limit reached
break;
}
else if (BeaconSendingResponseUtil.IsTooManyRequestsResponse(timeSyncResponse))
{
// special handling for too many requests
// clear all time sync offsets captured so far and store the response, which is handled later
response.timeSyncOffsets.Clear();
response.response = timeSyncResponse;
break;
}
else
{
context.Sleep(sleepTimeInMillis);
sleepTimeInMillis *= 2;
retry++;
}
}
return(response);
}
