public IObservable <ResourceEvent <TResource> > GetResource(ResourceStreamType type, TOptions options)
{
if (!_sharedInformers.TryGetValue(options, out var sharedInformer))
{
var optionLockedMasterInformer = _masterInformer.WithOptions(options);
sharedInformer = _sharedInformerFactory(optionLockedMasterInformer);
_sharedInformers.Add(options, sharedInformer);
}
return(sharedInformer.GetResource(type));
}
/// <inheritdoc cref="IKubernetesInformer{TResource}"/>
public IObservable <ResourceEvent <TResource> > GetResource(ResourceStreamType type) => base.GetResource(type, KubernetesInformerOptions.Default);
public KubernetesInformerEmitter(KubernetesInformer <TResource> parent, KubernetesInformerOptions options, ResourceStreamType type)
{
_parent = parent;
_options = options;
_type = type;
}
public IObservable <ResourceEvent <TResource> > GetResource(ResourceStreamType type, KubernetesInformerOptions options)
{
return(new KubernetesInformerEmitter(this, options, type).GetObservable());
}
public IObservable <ResourceEvent <TResource> > GetResource(ResourceStreamType type)
{
var childScheduler = new EventLoopScheduler(); // dedicated thread for the child on which all messages are syncrhonized
return(Observable.Defer(async() =>
{
AddSubscriber();
_logger.LogTrace("Subscriber awaiting cache synchronization before attaching");
var isCacheSynchronized = await _cacheSynchronized.Task;
if (!isCacheSynchronized) // really this only happens if the reset is the master completes before first reset, in which case the downstream subscriber gets nothing
{
return Observable.Empty <ResourceEvent <TResource> >();
}
// we use lock to pause any processing of the broadcaster while we're attaching to the stream so proper alignment can be made
_logger.LogTrace("Subscriber attaching to broadcaster");
return Observable.Create <ResourceEvent <TResource> >(observer =>
{
var broadcasterAttachment = Disposable.Empty;
var cacheSnapshot = _cache.Snapshot();
if (type.HasFlag(ResourceStreamType.List))
{
_logger.LogTrace($"Flushing contents of cache version {cacheSnapshot.Version}");
_cache.Values
.ToReset(type == ResourceStreamType.ListWatch)
.ToObservable()
.Concat(Observable.Never <ResourceEvent <TResource> >())
.ObserveOn(Scheduler.Immediate)
.Subscribe(observer);
}
if (type.HasFlag(ResourceStreamType.Watch))
{
broadcasterAttachment = _masterObservable
// we could be ahead of broadcaster because we initialized from cache which gets updated before the message are sent to broadcaster
// this logic realigns us at the correct point with the broadcaster
.Do(x => _logger.LogTrace($"Received from broadcaster {x}"))
.SkipWhile(x => x.MessageNumber <= cacheSnapshot.Version)
.Select(x => x.Value)
.Do(x => _logger.LogTrace($"Aligned with broadcaster {x}"))
.SubscribeOn(_masterScheduler)
.ObserveOn(childScheduler)
.Subscribe(observer, () =>
{
_logger.LogTrace("Child OnComplete");
RemoveSubscriber();
});
}
else
{
observer.OnCompleted();
}
// let broadcaster know we're done attaching to stream so it can resume it's regular work
_logger.LogTrace("Finished attaching to stream - signalling to resume");
lock (_lock)
{
_waitingSubscribers.Signal();
}
return broadcasterAttachment;
})
.ObserveOn(childScheduler)
.SubscribeOn(childScheduler);
})
.SubscribeOn(childScheduler) // ensures that when we attach master observer it's done on child thread, as we plan on awaiting cache synchronization
.Do(_ => _logger.LogTrace($"Shared informer out: {_}")));
}
public IObservable <ResourceEvent <TResource> > GetResource(ResourceStreamType type) => _informer.GetResource(type, _options);
