public void LevelDbWriteLogTest()
{
Version version;
{
DirectoryInfo directory = TestUtils.GetTestDirectory();
var currentStream = File.OpenText(Path.Combine(directory.FullName, "CURRENT"));
string manifestFilename = currentStream.ReadLine();
currentStream.Close();
Log.Debug($"Reading manifest from {manifestFilename}");
using var reader = new LogReader(new FileInfo($@"{directory}{manifestFilename}"));
version = Manifest.ReadVersionEdit(reader);
}
// Now we want to write this version
var stream = new MemoryStream();
{
Span <byte> bytes = Manifest.EncodeVersion(version);
Log.Debug($"Manifest (length:{bytes.Length}):\n{bytes.ToArray().HexDump()}");
var writer = new LogWriter(stream);
writer.WriteData(bytes);
Log.Debug($"Manifest (length:{stream.Position}):\n{stream.ToArray().HexDump()}");
}
{
stream.Position = 0;
using var verify = new LogReader(stream);
while (true)
{
ReadOnlySpan <byte> data = verify.ReadData();
if (verify.Eof)
{
break;
}
Log.Debug($"Data:\n{data.HexDump()}");
}
stream.Position = 0;
Manifest.ReadVersionEdit(verify);
}
}
public void LevelDbReadLogTest()
{
// https://github.com/google/leveldb/blob/master/doc/log_format.md
DirectoryInfo directory = TestUtils.GetTestDirectory();
LogReader logReader = new LogReader(new FileInfo(Path.Combine(directory.FullName, "000047.log")));
BytewiseComparator comparator = new BytewiseComparator();
bool found = false;
while (true)
{
ReadOnlySpan <byte> data = logReader.ReadData();
if (logReader.Eof)
{
break;
}
var dataReader = new SpanReader(data);
long sequenceNumber = dataReader.ReadInt64();
long size = dataReader.ReadInt32();
while (!dataReader.Eof)
{
byte recType = dataReader.ReadByte();
ulong v1 = dataReader.ReadVarLong();
var currentKey = dataReader.Read(v1);
//CurrentKey = f5 ff ff ff eb ff ff ff 36
if (comparator.Compare(new byte[] { 0xf5, 0xff, 0xff, 0xff, 0xeb, 0xff, 0xff, 0xff, 0x36 }, currentKey) == 0)
{
Assert.False(found);
found = true;
}
ulong v2 = 0;
ReadOnlySpan <byte> currentVal = ReadOnlySpan <byte> .Empty;
switch (recType)
{
case 1: // value
{
if (recType == 1)
{
v2 = dataReader.ReadVarLong();
currentVal = dataReader.Read(v2);
}
break;
}
case 0: // delete
{
//Assert.Fail("Unexpected delete key");
break;
}
default:
throw new Exception("Unknown record format");
}
if (Log.IsDebugEnabled)
{
Log.Debug($"RecType={recType}, Sequence={sequenceNumber}, Size={size}, v1={v1}, v2={v2}\nCurrentKey={currentKey.HexDump(currentKey.Length, false, false)}\nCurrentVal=\n{currentVal.HexDump(cutAfterFive: true)} ");
}
}
}
Assert.True(found);
}
