private async Task DoLongPollingRefresh(string appId, string cluster, string dataCenter, CancellationToken cancellationToken)
{
var random = new Random();
ServiceDto lastServiceDto = null;
while (!cancellationToken.IsCancellationRequested)
{
var sleepTime = 50; //default 50 ms
string url = null;
try
{
if (lastServiceDto == null)
{
var configServices = await _serviceLocator.GetConfigServices().ConfigureAwait(false);
lastServiceDto = configServices[random.Next(configServices.Count)];
}
url = AssembleLongPollRefreshUrl(lastServiceDto.HomepageUrl, appId, cluster, dataCenter);
Logger().Debug($"Long polling from {url}");
var response = await _httpUtil.DoGetAsync <IList <ApolloConfigNotification> >(url, 600000).ConfigureAwait(false);
Logger().Debug($"Long polling response: {response.StatusCode}, url: {url}");
if (response.StatusCode == HttpStatusCode.OK && response.Body != null)
{
UpdateNotifications(response.Body);
UpdateRemoteNotifications(response.Body);
Notify(lastServiceDto, response.Body);
_longPollSuccessSchedulePolicyInMs.Success();
}
else
{
sleepTime = _longPollSuccessSchedulePolicyInMs.Fail();
}
//try to load balance
if (response.StatusCode == HttpStatusCode.NotModified && random.NextDouble() >= 0.5)
{
lastServiceDto = null;
}
_longPollFailSchedulePolicyInSecond.Success();
}
catch (Exception ex)
{
lastServiceDto = null;
var sleepTimeInSecond = _longPollFailSchedulePolicyInSecond.Fail();
Logger().Warn($"Long polling failed, will retry in {sleepTimeInSecond} seconds. appId: {appId}, cluster: {cluster}, namespace: {string.Join(ConfigConsts.ClusterNamespaceSeparator, _longPollNamespaces.Keys)}, long polling url: {url}, reason: {ex.GetDetailMessage()}");
sleepTime = sleepTimeInSecond * 1000;
}
finally
{
await Task.Delay(sleepTime, cancellationToken).ConfigureAwait(false);
}
}
}
private async Task <ApolloConfig?> LoadApolloConfig(bool isFirst)
{
var appId = _options.AppId;
var cluster = _options.Cluster;
var dataCenter = _options.DataCenter;
var configServices = await _serviceLocator.GetConfigServices().ConfigureAwait(false);
Exception?exception = null;
string? url = null;
var notFound = false;
for (var i = 0; i < (isFirst ? 1 : 2); i++)
{
IList <ServiceDto> randomConfigServices = new List <ServiceDto>(configServices);
randomConfigServices.Shuffle();
//Access the server which notifies the client first
var longPollServiceDto = Interlocked.Exchange(ref _longPollServiceDto, null);
if (longPollServiceDto != null)
{
randomConfigServices.Insert(0, longPollServiceDto);
}
foreach (var configService in randomConfigServices)
{
url = AssembleQueryConfigUrl(configService.HomepageUrl, appId, cluster, Namespace, dataCenter, _remoteMessages !, _configCache !);
Logger().Debug($"Loading config from {url}");
try
{
var response = await _httpUtil.DoGetAsync <ApolloConfig>(url).ConfigureAwait(false);
if (response.StatusCode == HttpStatusCode.NotModified)
{
Logger().Debug("Config server responds with 304 HTTP status code.");
return(_configCache !);
}
var result = response.Body;
Logger().Debug(
$"Loaded config for {Namespace}: {result?.Configurations?.Count ?? 0}");
return(result);
}
catch (ApolloConfigStatusCodeException ex)
{
var statusCodeException = ex;
//config not found
if (ex.StatusCode == HttpStatusCode.NotFound)
{
notFound = true;
var message = $"Could not find config for namespace - appId: {appId}, cluster: {cluster}, namespace: {Namespace}, please check whether the configs are released in Apollo!";
statusCodeException = new ApolloConfigStatusCodeException(ex.StatusCode, message);
}
Logger().Warn(statusCodeException);
exception = statusCodeException;
}
catch (Exception ex)
{
Logger().Warn(ex);
exception = ex;
}
}
#if NET40
await TaskEx.Delay(1000).ConfigureAwait(false);
#else
await Task.Delay(1000).ConfigureAwait(false);
#endif
}
if (notFound)
{
return(null);
}
var fallbackMessage = $"Load Apollo Config failed - appId: {appId}, cluster: {cluster}, namespace: {Namespace}, url: {url}";
throw new ApolloConfigException(fallbackMessage, exception !);
}