private async Task ProcessSubscriptionAysnc()
{
if (_logger.IsInfoEnabled)
{
_logger.Info($"Starting proccessing documents for subscription {SubscriptionId} received from {TcpConnection.TcpClient.Client.RemoteEndPoint}");
}
DocumentsOperationContext dbContext;
using (DisposeOnDisconnect)
using (TcpConnection.DocumentDatabase.DocumentsStorage.ContextPool.AllocateOperationContext(out dbContext))
{
long startEtag;
SubscriptionCriteria criteria;
TcpConnection.DocumentDatabase.SubscriptionStorage.GetCriteriaAndEtag(_options.SubscriptionId, dbContext,
out criteria, out startEtag);
var replyFromClientTask = TcpConnection.MultiDocumentParser.ParseToMemoryAsync("client reply");
using (RegisterForNotificationOnNewDocuments(criteria))
{
var patch = SetupFilterScript(criteria);
while (CancellationTokenSource.IsCancellationRequested == false)
{
dbContext.ResetAndRenew();
bool anyDocumentsSentInCurrentIteration = false;
using (dbContext.OpenReadTransaction())
{
var documents = TcpConnection.DocumentDatabase.DocumentsStorage.GetDocumentsFrom(dbContext,
criteria.Collection,
startEtag + 1, 0, _options.MaxDocsPerBatch);
_buffer.SetLength(0);
var docsToFlush = 0;
var sendingCurrentBatchStopwatch = Stopwatch.StartNew();
foreach (var doc in documents)
{
anyDocumentsSentInCurrentIteration = true;
startEtag = doc.Etag;
if (DocumentMatchCriteriaScript(patch, dbContext, doc) == false)
{
// make sure that if we read a lot of irrelevant documents, we send keep alive over the network
if (sendingCurrentBatchStopwatch.ElapsedMilliseconds > 1000)
{
await SendHeartBeat();
sendingCurrentBatchStopwatch.Reset();
}
continue;
}
doc.EnsureMetadata();
TcpConnection.Context.Write(_bufferedWriter, new DynamicJsonValue
{
["Type"] = "Data",
["Data"] = doc.Data
});
docsToFlush++;
// perform flush for current batch after 1000ms of running
if (sendingCurrentBatchStopwatch.ElapsedMilliseconds > 1000)
{
if (docsToFlush > 0)
{
await FlushDocsToClient(docsToFlush);
docsToFlush = 0;
sendingCurrentBatchStopwatch.Reset();
}
else
{
await SendHeartBeat();
}
}
}
if (anyDocumentsSentInCurrentIteration)
{
TcpConnection.Context.Write(_bufferedWriter, new DynamicJsonValue
{
["Type"] = "EndOfBatch"
});
await FlushDocsToClient(docsToFlush, true);
}
if (anyDocumentsSentInCurrentIteration == false)
{
if (await WaitForChangedDocuments(replyFromClientTask))
{
continue;
}
}
SubscriptionConnectionClientMessage clientReply;
while (true)
{
var result =
await Task.WhenAny(replyFromClientTask, Task.Delay(TimeSpan.FromSeconds(5), CancellationTokenSource.Token));
if (result == replyFromClientTask)
{
using (var reply = await replyFromClientTask)
{
TcpConnection.RegisterBytesReceived(reply.Size);
clientReply = JsonDeserializationServer.SubscriptionConnectionClientMessage(reply);
}
TcpConnection.ResetAndRenew();
replyFromClientTask = TcpConnection.MultiDocumentParser.ParseToMemoryAsync("client reply");
break;
}
await SendHeartBeat();
}
switch (clientReply.Type)
{
case SubscriptionConnectionClientMessage.MessageType.Acknowledge:
TcpConnection.DocumentDatabase.SubscriptionStorage.AcknowledgeBatchProcessed(_options.SubscriptionId,
clientReply.Etag);
Stats.LastAckReceivedAt = DateTime.UtcNow;
Stats.AckRate.Mark();
await WriteJsonAsync(new DynamicJsonValue
{
["Type"] = "Confirm",
["Etag"] = clientReply.Etag
});
break;
default:
throw new ArgumentException("Unknown message type from client " +
clientReply.Type);
}
}
}
}
}
}