private void StreamToClient(long id, SubscriptionActions subscriptions, Stream stream)
{
var sentDocuments = false;
var bufferStream = new BufferedStream(stream, 1024 * 64);
var lastBatchSentTime = Stopwatch.StartNew();
using (var writer = new JsonTextWriter(new StreamWriter(bufferStream)))
{
var options = subscriptions.GetBatchOptions(id);
writer.WriteStartObject();
writer.WritePropertyName("Results");
writer.WriteStartArray();
using (var cts = new CancellationTokenSource())
using (var timeout = cts.TimeoutAfter(DatabasesLandlord.SystemConfiguration.DatabaseOperationTimeout))
{
Etag lastProcessedDocEtag = null;
var batchSize = 0;
var batchDocCount = 0;
var processedDocumentsCount = 0;
var hasMoreDocs = false;
var config = subscriptions.GetSubscriptionConfig(id);
var startEtag = config.AckEtag;
var criteria = config.Criteria;
bool isPrefixCriteria = !string.IsNullOrWhiteSpace(criteria.KeyStartsWith);
Func<JsonDocument, bool> addDocument = doc =>
{
timeout.Delay();
if (doc == null)
{
// we only have this heartbeat when the streaming has gone on for a long time
// and we haven't sent anything to the user in a while (because of filtering, skipping, etc).
writer.WriteRaw(Environment.NewLine);
writer.Flush();
if (lastBatchSentTime.ElapsedMilliseconds > 30000)
return false;
return true;
}
processedDocumentsCount++;
// We cant continue because we have already maxed out the batch bytes size.
if (options.MaxSize.HasValue && batchSize >= options.MaxSize)
return false;
// We cant continue because we have already maxed out the amount of documents to send.
if (batchDocCount >= options.MaxDocCount)
return false;
// We can continue because we are ignoring system documents.
if (doc.Key.StartsWith("Raven/", StringComparison.InvariantCultureIgnoreCase))
return true;
// We can continue because we are ignoring the document as it doesn't fit the criteria.
if (MatchCriteria(criteria, doc) == false)
return true;
doc.ToJson().WriteTo(writer);
writer.WriteRaw(Environment.NewLine);
batchSize += doc.SerializedSizeOnDisk;
batchDocCount++;
return true; // We get the next document
};
var retries = 0;
do
{
var lastProcessedDocumentsCount = processedDocumentsCount;
Database.TransactionalStorage.Batch(accessor =>
{
// we may be sending a LOT of documents to the user, and most
// of them aren't going to be relevant for other ops, so we are going to skip
// the cache for that, to avoid filling it up very quickly
using (DocumentCacher.SkipSetAndGetDocumentsInDocumentCache())
{
if (isPrefixCriteria)
{
// If we don't get any document from GetDocumentsWithIdStartingWith it could be that we are in presence of a lagoon of uninteresting documents, so we are hitting a timeout.
lastProcessedDocEtag = Database.Documents.GetDocumentsWithIdStartingWith(criteria.KeyStartsWith, options.MaxDocCount - batchDocCount, startEtag, cts.Token, addDocument);
hasMoreDocs = false;
}
else
{
// It doesn't matter if we match the criteria or not, the document has been already processed.
lastProcessedDocEtag = Database.Documents.GetDocuments(-1, options.MaxDocCount - batchDocCount, startEtag, cts.Token, addDocument);
// If we don't get any document from GetDocuments it may be a signal that something is wrong.
if (lastProcessedDocEtag == null)
{
hasMoreDocs = false;
}
else
{
var lastDocEtag = accessor.Staleness.GetMostRecentDocumentEtag();
hasMoreDocs = EtagUtil.IsGreaterThan(lastDocEtag, lastProcessedDocEtag);
startEtag = lastProcessedDocEtag;
}
retries = lastProcessedDocumentsCount == batchDocCount ? retries : 0;
}
}
});
if (lastBatchSentTime.ElapsedMilliseconds >= 30000)
{
if (batchDocCount == 0)
log.Warn("Subscription filtered out all possible documents for {0:#,#;;0} seconds in a row, stopping operation", lastBatchSentTime.Elapsed.TotalSeconds);
break;
}
if (lastProcessedDocumentsCount == processedDocumentsCount)
{
if (retries == 3)
{
log.Warn("Subscription processing did not end up replicating any documents for 3 times in a row, stopping operation", retries);
}
else
{
log.Warn("Subscription processing did not end up replicating any documents, due to possible storage error, retry number: {0}", retries);
}
retries++;
}
} while (retries < 3 && hasMoreDocs && batchDocCount < options.MaxDocCount && (options.MaxSize.HasValue == false || batchSize < options.MaxSize));
writer.WriteEndArray();
if (batchDocCount > 0 || processedDocumentsCount > 0 || isPrefixCriteria)
{
writer.WritePropertyName("LastProcessedEtag");
writer.WriteValue(lastProcessedDocEtag.ToString());
sentDocuments = true;
}
writer.WriteEndObject();
writer.Flush();
bufferStream.Flush();
}
}
if (sentDocuments)
subscriptions.UpdateBatchSentTime(id);
}
private void StreamToClient(long id, SubscriptionActions subscriptions, Stream stream)
{
var sentDocuments = false;
using (var streamWriter = new StreamWriter(stream))
using (var writer = new JsonTextWriter(streamWriter))
{
var options = subscriptions.GetBatchOptions(id);
writer.WriteStartObject();
writer.WritePropertyName("Results");
writer.WriteStartArray();
using (var cts = new CancellationTokenSource())
using (var timeout = cts.TimeoutAfter(DatabasesLandlord.SystemConfiguration.DatabaseOperationTimeout))
{
Etag lastProcessedDocEtag = null;
var batchSize = 0;
var batchDocCount = 0;
var hasMoreDocs = false;
var config = subscriptions.GetSubscriptionConfig(id);
var startEtag = config.AckEtag;
var criteria = config.Criteria;
Action<JsonDocument> addDocument = doc =>
{
timeout.Delay();
if (options.MaxSize.HasValue && batchSize >= options.MaxSize)
return;
if (batchDocCount >= options.MaxDocCount)
return;
lastProcessedDocEtag = doc.Etag;
if (doc.Key.StartsWith("Raven/", StringComparison.InvariantCultureIgnoreCase))
return;
if (MatchCriteria(criteria, doc) == false)
return;
doc.ToJson().WriteTo(writer);
writer.WriteRaw(Environment.NewLine);
batchSize += doc.SerializedSizeOnDisk;
batchDocCount++;
};
int nextStart = 0;
do
{
Database.TransactionalStorage.Batch(accessor =>
{
// we may be sending a LOT of documents to the user, and most
// of them aren't going to be relevant for other ops, so we are going to skip
// the cache for that, to avoid filling it up very quickly
using (DocumentCacher.SkipSettingDocumentsInDocumentCache())
{
if (!string.IsNullOrWhiteSpace(criteria.KeyStartsWith))
{
Database.Documents.GetDocumentsWithIdStartingWith(criteria.KeyStartsWith, options.MaxDocCount - batchDocCount, startEtag, cts.Token, addDocument);
}
else
{
Database.Documents.GetDocuments(-1, options.MaxDocCount - batchDocCount, startEtag, cts.Token, addDocument);
}
}
if (lastProcessedDocEtag == null)
hasMoreDocs = false;
else
{
var lastDocEtag = accessor.Staleness.GetMostRecentDocumentEtag();
hasMoreDocs = EtagUtil.IsGreaterThan(lastDocEtag, lastProcessedDocEtag);
startEtag = lastProcessedDocEtag;
}
});
} while (hasMoreDocs && batchDocCount < options.MaxDocCount && (options.MaxSize.HasValue == false || batchSize < options.MaxSize));
writer.WriteEndArray();
if (batchDocCount > 0)
{
writer.WritePropertyName("LastProcessedEtag");
writer.WriteValue(lastProcessedDocEtag.ToString());
sentDocuments = true;
}
writer.WriteEndObject();
writer.Flush();
}
}
if (sentDocuments)
subscriptions.UpdateBatchSentTime(id);
}