public IObservable <IEnumerable <string> > Listen()
{
CreateStoresIfNotExistsAsync().Wait();
var stream = Observable.Create <IEnumerable <string> >(obs =>
{
var factory = new SampleObserverFactory(obs);
var processor = new ChangeFeedProcessorBuilder()
.WithFeedCollection(new DocumentCollectionInfo {
Uri = CosmosUri, MasterKey = CosmosKey, DatabaseName = DatabaseName, CollectionName = MonitoredCollection
})
.WithLeaseCollection(new DocumentCollectionInfo {
Uri = CosmosUri, MasterKey = CosmosKey, DatabaseName = DatabaseName, CollectionName = LeaseCollection
})
.WithHostName("SampleHost")
.WithObserverFactory(factory)
/* the explicit checkpoint is important because otherwise when the stream blows, it still checkpoints, and we 'lose' the message */
.WithProcessorOptions(new ChangeFeedProcessorOptions {
MaxItemCount = 2, CheckpointFrequency = new CheckpointFrequency {
ExplicitCheckpoint = true
}
})
.BuildAsync().Result;
processor.StartAsync().Wait();
var sub = Tuple.Create(obs, processor);
Subscriptions.Add(sub);
return(Disposable.Create(() =>
{
// the ConfigureAwait(false) is *critical* to ensure the processor stops!
processor.StopAsync().ConfigureAwait(false).AsTask().Wait();
Subscriptions.Remove(sub);
Log.Warning("Disposable run for subscription");
}));
});
Log.Information("Subscription created");
return(stream);
}