public async Task <long> GetLastDocId()
{
if (_file.Length == 0)
{
return(0);
}
var initialPos = _file.Position;
try
{
var compression = new CompressionUtils();
var segment = await compression.ReadWithDecompressionFromRightToLeft(_file);
using (var ms = new MemoryStream(segment.Array, segment.Offset, segment.Count))
{
var batch = await DocumentSerializer.DeserializeBatch(ms).ConfigureAwait(false);
return(batch.Last().Id);
}
}
finally
{
_file.Position = initialPos;
}
}
public async Task <List <Document> > GetChunk(long offset)
{
var compression = new CompressionUtils();
if (offset >= _file.Length)
{
// should NEVER happen
throw new InvalidOperationException("Specified position doesn't exist in data file");
}
using (var file = new FileStream(_filePath, FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
{
var segment = await compression.ReadWithDecompression(file, offset);
using (var ms = new MemoryStream(segment.Array, segment.Offset, segment.Count))
{
var batch = await DocumentSerializer.DeserializeBatch(ms).ConfigureAwait(false);
return(batch);
}
}
}