private ClientMessage.ReadAllEventsBackwardCompleted NoData(ClientMessage.ReadAllEventsBackward msg,
ReadAllResult result, TFPos pos, long lastCommitPosition, string error = null)
{
return(new ClientMessage.ReadAllEventsBackwardCompleted(
msg.CorrelationId, result, error, ResolvedEvent.EmptyArray, null, false,
msg.MaxCount, pos, TFPos.Invalid, TFPos.Invalid, lastCommitPosition));
}
public static ClientMessage.ReadAllEventsBackwardCompleted ReadAllEventsBackward(MiniClusterNode node,
long position)
{
ClientMessage.ReadAllEventsBackwardCompleted readResult = null;
var resetEvent = new ManualResetEventSlim();
var done = false;
while (!done)
{
resetEvent.Reset();
var read = new ClientMessage.ReadAllEventsBackward(Guid.NewGuid(), Guid.NewGuid(), new CallbackEnvelope(
msg => {
readResult = (ClientMessage.ReadAllEventsBackwardCompleted)msg;
resetEvent.Set();
}),
-1, -1, 100, false, false, null, SystemAccount.Principal);
node.Node.MainQueue.Publish(read);
if (!resetEvent.Wait(_timeout))
{
Assert.Fail("Timed out waiting for events to be read backward");
return(null);
}
if (readResult.Result == ReadAllResult.Error)
{
Assert.Fail("Failed to read backwards. Read result error: {0}", readResult.Error);
return(null);
}
done = readResult.NextPos.CommitPosition < position;
}
return(readResult);
}
void IHandle <ClientMessage.ReadAllEventsBackward> .Handle(ClientMessage.ReadAllEventsBackward msg)
{
if (msg.Expires < DateTime.Now)
{
return;
}
msg.Envelope.ReplyWith(ReadAllEventsBackward(msg));
}
void IHandle <ClientMessage.ReadAllEventsBackward> .Handle(ClientMessage.ReadAllEventsBackward msg)
{
if (msg.Expires < DateTime.UtcNow)
{
Log.Debug("Read All Stream Events Backward operation has expired for C:{0}/P:{1}. Operation Expired at {2}", msg.CommitPosition, msg.PreparePosition, msg.Expires);
return;
}
msg.Envelope.ReplyWith(ReadAllEventsBackward(msg));
}
public TcpPackage CreateNetworkPackage()
{
lock (_corrIdLock)
{
var dto = new ClientMessage.ReadAllEventsBackward(_position.CommitPosition,
_position.PreparePosition,
_maxCount,
_resolveLinkTos);
return(new TcpPackage(TcpCommand.ReadAllEventsBackward, _corrId, dto.Serialize()));
}
}
private ClientMessage.ReadAllEventsBackwardCompleted ReadAllEventsBackward(ClientMessage.ReadAllEventsBackward msg)
{
using (HistogramService.Measure(_readerAllRangeHistogram))
{
var pos = new TFPos(msg.CommitPosition, msg.PreparePosition);
var lastCommitPosition = _readIndex.LastReplicatedPosition;
try
{
if (msg.MaxCount > MaxPageSize)
{
throw new ArgumentException(string.Format("Read size too big, should be less than {0} items",
MaxPageSize));
}
if (pos == TFPos.HeadOfTf)
{
var checkpoint = _writerCheckpoint.Read();
pos = new TFPos(checkpoint, checkpoint);
}
if (pos.CommitPosition < 0 || pos.PreparePosition < 0)
{
return(NoData(msg, ReadAllResult.Error, pos, lastCommitPosition, "Invalid position."));
}
if (msg.ValidationTfLastCommitPosition == lastCommitPosition)
{
return(NoData(msg, ReadAllResult.NotModified, pos, lastCommitPosition));
}
var access = _readIndex.CheckStreamAccess(SystemStreams.AllStream, StreamAccessType.Read, msg.User);
if (!access.Granted)
{
return(NoData(msg, ReadAllResult.AccessDenied, pos, lastCommitPosition));
}
var res = _readIndex.ReadAllEventsBackward(pos, msg.MaxCount);
var resolved = ResolveReadAllResult(res.Records, msg.ResolveLinkTos, msg.User);
if (resolved == null)
{
return(NoData(msg, ReadAllResult.AccessDenied, pos, lastCommitPosition));
}
var metadata = _readIndex.GetStreamMetadata(SystemStreams.AllStream);
return(new ClientMessage.ReadAllEventsBackwardCompleted(
msg.CorrelationId, ReadAllResult.Success, null, resolved, metadata, access.Public, msg.MaxCount,
res.CurrentPos, res.NextPos, res.PrevPos, lastCommitPosition));
}
catch (Exception exc)
{
Log.ErrorException(exc, "Error during processing ReadAllEventsBackward request.");
return(NoData(msg, ReadAllResult.Error, pos, lastCommitPosition, exc.Message));
}
}
}
void IHandle <ClientMessage.ReadAllEventsBackward> .Handle(ClientMessage.ReadAllEventsBackward message)
{
var pos = new TFPos(message.CommitPosition, message.PreparePosition);
if (pos == new TFPos(-1, -1))
{
var checkpoint = _writerCheckpoint.Read();
pos = new TFPos(checkpoint, checkpoint);
}
var result = _readIndex.ReadAllEventsBackward(pos, message.MaxCount, message.ResolveLinks);
message.Envelope.ReplyWith(new ClientMessage.ReadAllEventsBackwardCompleted(message.CorrelationId, result));
}
public Task <AllEventsSlice> ReadAllEventsBackwardAsync(Position position, int maxCount, bool resolveLinkTos, UserCredentials userCredentials = null)
{
Ensure.Positive(maxCount, "maxCount");
var source = new TaskCompletionSource <AllEventsSlice>();
var envelope = new EmbeddedResponseEnvelope(new EmbeddedResponders.ReadAllEventsBackward(source));
Guid corrId = Guid.NewGuid();
var message = new ClientMessage.ReadAllEventsBackward(corrId, corrId, envelope,
position.CommitPosition,
position.PreparePosition, maxCount, resolveLinkTos, false, null, SystemAccount.Principal);
_publisher.Publish(message);
return(source.Task);
}
private void HandleAsNonMaster(ClientMessage.ReadAllEventsBackward message)
{
if (message.RequireMaster)
{
if (_master == null)
{
DenyRequestBecauseNotReady(message.Envelope, message.CorrelationId);
}
else
{
DenyRequestBecauseNotMaster(message.CorrelationId, message.Envelope);
}
}
else
{
_outputBus.Publish(message);
}
}
private ClientMessage.ReadAllEventsBackwardCompleted ReadAllEventsBackward(ClientMessage.ReadAllEventsBackward msg)
{
var pos = new TFPos(msg.CommitPosition, msg.PreparePosition);
try
{
if (pos == TFPos.HeadOfTf)
{
var checkpoint = _writerCheckpoint.Read();
pos = new TFPos(checkpoint, checkpoint);
}
if (pos.CommitPosition < 0 || pos.PreparePosition < 0)
{
return(NoData(msg, ReadAllResult.Error, pos, "Invalid position."));
}
if (msg.ValidationTfEofPosition.HasValue && _readIndex.LastCommitPosition == msg.ValidationTfEofPosition.Value)
{
return(NoData(msg, ReadAllResult.NotModified, pos));
}
var access = _readIndex.CheckStreamAccess(SystemStreams.AllStream, StreamAccessType.Read, msg.User);
if (!access.Granted)
{
return(NoData(msg, ReadAllResult.AccessDenied, pos));
}
var res = _readIndex.ReadAllEventsBackward(pos, msg.MaxCount);
var resolved = ResolveReadAllResult(res.Records, msg.ResolveLinkTos, msg.User);
if (resolved == null)
{
return(NoData(msg, ReadAllResult.AccessDenied, pos));
}
return(new ClientMessage.ReadAllEventsBackwardCompleted(
msg.CorrelationId, ReadAllResult.Success, null, resolved, res.Metadata, access.Public, msg.MaxCount,
res.CurrentPos, res.NextPos, res.PrevPos, res.TfEofPosition));
}
catch (Exception exc)
{
Log.ErrorException(exc, "Error during processing ReadAllEventsBackward request.");
return(NoData(msg, ReadAllResult.Error, pos, exc.Message));
}
}
void IHandle <ClientMessage.ReadAllEventsBackward> .Handle(ClientMessage.ReadAllEventsBackward msg)
{
msg.Envelope.ReplyWith(ReadAllEventsBackward(msg));
}
