private async Task SubscribeToStreamAsync()
{
if (!ShouldStop)
{
if (Verbose)
{
Log.Debug("Catch-up Subscription {0} to {1}: subscribing...", SubscriptionName, IsSubscribedToAll ? "<all>" : StreamId);
}
StreamSubscription storeSubscription;
if (StreamId == string.Empty)
{
storeSubscription = _connection.SubscribeToAll(EnqueuePushedEvent, ServerSubscriptionDropped, _userCredentials);
}
else
{
storeSubscription = _connection.SubscribeToStream(StreamId, EnqueuePushedEvent, ServerSubscriptionDropped, _userCredentials);
}
_subscription = storeSubscription;
await ReadMissedHistoricEventsAsync().ConfigureAwait(false);
}
else
{
DropSubscription(SubscriptionDropReason.UserInitiated, null);
}
}
private void EnqueuePushedEvent(StreamSubscription subscription, RecordedEvent e)
{
if (Verbose)
{
Log.Debug($"Catch-up Subscription {SubscriptionName} to {(IsSubscribedToAll ? "<all>" : StreamId)}: event appeared ({e.EventStreamId}, {e.EventNumber}, {e.EventType}).");
}
if (_liveQueue.Count >= MaxPushQueueSize)
{
EnqueueSubscriptionDropNotification(SubscriptionDropReason.ProcessingQueueOverflow, null);
subscription.Unsubscribe();
}
_liveQueue.Enqueue(e);
if (_allowProcessing)
{
EnsureProcessingPushQueue();
}
}
internal void DropSubscription(SubscriptionDropReason reason, Exception error)
{
if (Interlocked.CompareExchange(ref _isDropped, 1, 0) != 0)
{
return;
}
if (Verbose)
{
Log.Debug("Catch-up Subscription {0} to {1}: dropping subscription, reason: {2} {3}.", SubscriptionName, IsSubscribedToAll ? "<all>" : StreamId, reason, error == null ? string.Empty : error.ToString());
}
StreamSubscription subscription = _subscription;
if (subscription != null)
{
subscription.Unsubscribe();
}
Action <CatchUpSubscription, SubscriptionDropReason, Exception> subscriptionDropped = _subscriptionDropped;
if (subscriptionDropped != null)
{
subscriptionDropped(this, reason, error);
}
_stopped.Set();
}
private void ServerSubscriptionDropped(StreamSubscription subscription, SubscriptionDropReason reason, Exception exc)
{
EnqueueSubscriptionDropNotification(reason, exc);
}