/// <exception cref="Javax.Servlet.ServletException"/>
/// <exception cref="System.IO.IOException"/>
protected override void DoGet(HttpServletRequest request, HttpServletResponse response
)
{
FileInputStream editFileIn = null;
try
{
ServletContext context = GetServletContext();
Configuration conf = (Configuration)GetServletContext().GetAttribute(JspHelper.CurrentConf
);
string journalId = request.GetParameter(JournalIdParam);
QuorumJournalManager.CheckJournalId(journalId);
JNStorage storage = JournalNodeHttpServer.GetJournalFromContext(context, journalId
).GetStorage();
// Check security
if (!CheckRequestorOrSendError(conf, request, response))
{
return;
}
// Check that the namespace info is correct
if (!CheckStorageInfoOrSendError(storage, request, response))
{
return;
}
long segmentTxId = ServletUtil.ParseLongParam(request, SegmentTxidParam);
FileJournalManager fjm = storage.GetJournalManager();
FilePath editFile;
lock (fjm)
{
// Synchronize on the FJM so that the file doesn't get finalized
// out from underneath us while we're in the process of opening
// it up.
FileJournalManager.EditLogFile elf = fjm.GetLogFile(segmentTxId);
if (elf == null)
{
response.SendError(HttpServletResponse.ScNotFound, "No edit log found starting at txid "
+ segmentTxId);
return;
}
editFile = elf.GetFile();
ImageServlet.SetVerificationHeadersForGet(response, editFile);
ImageServlet.SetFileNameHeaders(response, editFile);
editFileIn = new FileInputStream(editFile);
}
DataTransferThrottler throttler = ImageServlet.GetThrottler(conf);
// send edits
TransferFsImage.CopyFileToStream(response.GetOutputStream(), editFile, editFileIn
, throttler);
}
catch (Exception t)
{
string errMsg = "getedit failed. " + StringUtils.StringifyException(t);
response.SendError(HttpServletResponse.ScInternalServerError, errMsg);
throw new IOException(errMsg);
}
finally
{
IOUtils.CloseStream(editFileIn);
}
}
/// <exception cref="System.IO.IOException"/>
internal virtual Journal GetOrCreateJournal(string jid, HdfsServerConstants.StartupOption
startOpt)
{
lock (this)
{
QuorumJournalManager.CheckJournalId(jid);
Journal journal = journalsById[jid];
if (journal == null)
{
FilePath logDir = GetLogDir(jid);
Log.Info("Initializing journal in directory " + logDir);
journal = new Journal(conf, logDir, jid, startOpt, new JournalNode.ErrorReporter(
this));
journalsById[jid] = journal;
}
return(journal);
}
}
/// <exception cref="System.IO.IOException"/>
public static EditLogOutputStream WriteSegment(MiniJournalCluster cluster, QuorumJournalManager
qjm, long startTxId, int numTxns, bool finalize)
{
EditLogOutputStream stm = qjm.StartLogSegment(startTxId, NameNodeLayoutVersion.CurrentLayoutVersion
);
// Should create in-progress
AssertExistsInQuorum(cluster, NNStorage.GetInProgressEditsFileName(startTxId));
WriteTxns(stm, startTxId, numTxns);
if (finalize)
{
stm.Close();
qjm.FinalizeLogSegment(startTxId, startTxId + numTxns - 1);
return(null);
}
else
{
return(stm);
}
}
/// <exception cref="System.IO.IOException"/>
public static long RecoverAndReturnLastTxn(QuorumJournalManager qjm)
{
qjm.RecoverUnfinalizedSegments();
long lastRecoveredTxn = 0;
IList <EditLogInputStream> streams = Lists.NewArrayList();
try
{
qjm.SelectInputStreams(streams, 0, false);
foreach (EditLogInputStream elis in streams)
{
NUnit.Framework.Assert.IsTrue(elis.GetFirstTxId() > lastRecoveredTxn);
lastRecoveredTxn = elis.GetLastTxId();
}
}
finally
{
IOUtils.Cleanup(null, Sharpen.Collections.ToArray(streams, new IDisposable[0]));
}
return(lastRecoveredTxn);
}