/// <summary>
/// Creates a stream
/// </summary>
/// <param name="streamId">Stream Id</param>
public StorageStream CreateStream(Guid streamId, int tag = 0)
{
CheckClosed();
if (SystemStreamId.IsSystemStreamId(streamId))
{
throw new InvalidStreamIdException();
}
if (ContainsStream(streamId))
{
throw new StreamExistsException();
}
StartTransaction();
try
{
streamTable.Add(streamId, tag);
CommitTransaction();
streamsCreatedDuringTransaction.Add(streamId);
}
catch
{
RollbackTransaction();
throw;
}
return(OpenStream(streamId));
}
internal void StreamChanged(StorageStreamChangeType changeType, StorageStream stream)
{
if (!SystemStreamId.IsSystemStreamId(stream.StreamId) || stream.StreamId == SystemStreamId.EmptySpace)
{
switch (changeType)
{
case StorageStreamChangeType.SegmentsAndMetadata:
if (!streamsChangedDuringTransaction.Contains(stream))
{
streamsChangedDuringTransaction.Add(stream);
}
break;
case StorageStreamChangeType.Closing:
if (streamsChangedDuringTransaction.Contains(stream))
{
streamsChangedDuringTransaction.Remove(stream);
}
openedStreams.Remove(stream.StreamId);
//e.Stream.Changed -= StorageStream_Changed;
break;
}
}
}
/// <summary>
/// Gets all of the stream Id's
/// </summary>
/// <param name="tag">If specified, only streams with specified tag are returned</param>
public IEnumerable <Guid> GetStreams(int?tag)
{
return(streamTable.Get()
.Where(x => !SystemStreamId.IsSystemStreamId(x.StreamId))
.Where(x => !tag.HasValue || x.Tag == tag.Value)
.Select(x => x.StreamId)
.ToList());
}
/// <summary>
/// Checks if storage contains specified stream
/// </summary>
public bool ContainsStream(Guid streamId)
{
CheckClosed();
if (SystemStreamId.IsSystemStreamId(streamId))
{
throw new InvalidStreamIdException();
}
return(streamTable.Contains(streamId));
}
/// <summary>
/// Opens a stream
/// </summary>
/// <param name="streamId">Stream Id</param>
public StorageStream OpenStream(Guid streamId)
{
CheckClosed();
if (SystemStreamId.IsSystemStreamId(streamId))
{
throw new InvalidStreamIdException();
}
StartTransaction();
try
{
StorageStream tmpStream = null;
WeakReference <StorageStream> streamRef;
// Check if stream is already opened
if (openedStreams.TryGetValue(streamId, out streamRef))
{
if (!streamRef.TryGetTarget(out tmpStream))
{
tmpStream = null;
openedStreams.Remove(streamId);
}
}
// Open stream
if (tmpStream == null)
{
var streamMetadata = streamTable.Get(streamId);
if (streamMetadata == null)
{
throw new StreamNotFoundException();
}
tmpStream = new StorageStream(streamMetadata, this);
//tmpStream.Changed += StorageStream_Changed;
openedStreams.Add(streamId, new WeakReference <StorageStream>(tmpStream));
}
tmpStream.Position = 0;
CommitTransaction();
return(tmpStream);
}
catch
{
RollbackTransaction();
throw;
}
}
/// <summary>
/// Gets areas where specified stream segments are located
/// </summary>
public List <SegmentExtent> GetStreamExtents(Guid streamId)
{
CheckClosed();
if (SystemStreamId.IsSystemStreamId(streamId))
{
throw new InvalidStreamIdException();
}
StorageStream stream = OpenStream(streamId);
return(stream.GetStreamExtents());
}
/// <summary>
/// Deletes a stream
/// </summary>
/// <param name="streamId">Stream Id</param>
public void DeleteStream(Guid streamId)
{
CheckClosed();
if (SystemStreamId.IsSystemStreamId(streamId))
{
throw new InvalidStreamIdException();
}
StartTransaction();
try
{
// Before deleting, set stream size to zero to deallocate all of the space it occupies
StorageStream tmpStream = OpenStream(streamId);
tmpStream.SetLength(0);
tmpStream.Close();
openedStreams.Remove(streamId);
streamTable.Remove(streamId);
// Remove stream from list of changed streams
tmpStream = streamsChangedDuringTransaction.SingleOrDefault(x => x.StreamId == streamId);
if (tmpStream != null)
{
streamsChangedDuringTransaction.Remove(tmpStream);
}
// Remove stream from list of created streams
if (streamsCreatedDuringTransaction.Contains(streamId))
{
streamsCreatedDuringTransaction.Remove(streamId);
}
CommitTransaction();
}
catch
{
RollbackTransaction();
throw;
}
}
