/// <summary>Delete a snapshot for a snapshottable directory</summary>
/// <param name="snapshotName">Name of the snapshot to be deleted</param>
/// <param name="collectedBlocks">Used to collect information to update blocksMap</param>
/// <exception cref="System.IO.IOException"/>
public virtual void DeleteSnapshot(INodesInPath iip, string snapshotName, INode.BlocksMapUpdateInfo
collectedBlocks, IList <INode> removedINodes)
{
INodeDirectory srcRoot = GetSnapshottableRoot(iip);
srcRoot.RemoveSnapshot(fsdir.GetBlockStoragePolicySuite(), snapshotName, collectedBlocks
, removedINodes);
numSnapshots.GetAndDecrement();
}
/// <summary>
/// Find the source root directory where the snapshot will be taken
/// for a given path.
/// </summary>
/// <returns>Snapshottable directory.</returns>
/// <exception cref="System.IO.IOException">
/// Throw IOException when the given path does not lead to an
/// existing snapshottable directory.
/// </exception>
public virtual INodeDirectory GetSnapshottableRoot(INodesInPath iip)
{
string path = iip.GetPath();
INodeDirectory dir = INodeDirectory.ValueOf(iip.GetLastINode(), path);
if (!dir.IsSnapshottable())
{
throw new SnapshotException("Directory is not a snapshottable directory: " + path
);
}
return(dir);
}
/// <summary>Test that the global limit on snapshots is honored.</summary>
/// <exception cref="System.Exception"/>
public virtual void TestSnapshotLimits()
{
// Setup mock objects for SnapshotManager.createSnapshot.
//
INodeDirectory ids = Org.Mockito.Mockito.Mock <INodeDirectory>();
FSDirectory fsdir = Org.Mockito.Mockito.Mock <FSDirectory>();
INodesInPath iip = Org.Mockito.Mockito.Mock <INodesInPath>();
SnapshotManager sm = Org.Mockito.Mockito.Spy(new SnapshotManager(fsdir));
Org.Mockito.Mockito.DoReturn(ids).When(sm).GetSnapshottableRoot((INodesInPath)Matchers.AnyObject
());
Org.Mockito.Mockito.DoReturn(testMaxSnapshotLimit).When(sm).GetMaxSnapshotID();
// Create testMaxSnapshotLimit snapshots. These should all succeed.
//
for (int i = 0; i < testMaxSnapshotLimit; ++i)
{
sm.CreateSnapshot(iip, "dummy", i.ToString());
}
// Attempt to create one more snapshot. This should fail due to snapshot
// ID rollover.
//
try
{
sm.CreateSnapshot(iip, "dummy", "shouldFailSnapshot");
NUnit.Framework.Assert.Fail("Expected SnapshotException not thrown");
}
catch (SnapshotException se)
{
NUnit.Framework.Assert.IsTrue(StringUtils.ToLowerCase(se.Message).Contains("rollover"
));
}
// Delete a snapshot to free up a slot.
//
sm.DeleteSnapshot(iip, string.Empty, Org.Mockito.Mockito.Mock <INode.BlocksMapUpdateInfo
>(), new AList <INode>());
// Attempt to create a snapshot again. It should still fail due
// to snapshot ID rollover.
//
try
{
sm.CreateSnapshot(iip, "dummy", "shouldFailSnapshot2");
NUnit.Framework.Assert.Fail("Expected SnapshotException not thrown");
}
catch (SnapshotException se)
{
NUnit.Framework.Assert.IsTrue(StringUtils.ToLowerCase(se.Message).Contains("rollover"
));
}
}
/// <summary>
/// Compute the difference between two snapshots of a directory, or between a
/// snapshot of the directory and its current tree.
/// </summary>
/// <exception cref="System.IO.IOException"/>
public virtual SnapshotDiffReport Diff(INodesInPath iip, string snapshotRootPath,
string from, string to)
{
// Find the source root directory path where the snapshots were taken.
// All the check for path has been included in the valueOf method.
INodeDirectory snapshotRoot = GetSnapshottableRoot(iip);
if ((from == null || from.IsEmpty()) && (to == null || to.IsEmpty()))
{
// both fromSnapshot and toSnapshot indicate the current tree
return(new SnapshotDiffReport(snapshotRootPath, from, to, Sharpen.Collections.EmptyList
<SnapshotDiffReport.DiffReportEntry>()));
}
SnapshotDiffInfo diffs = snapshotRoot.GetDirectorySnapshottableFeature().ComputeDiff
(snapshotRoot, from, to);
return(diffs != null?diffs.GenerateReport() : new SnapshotDiffReport(snapshotRootPath
, from, to, Sharpen.Collections.EmptyList <SnapshotDiffReport.DiffReportEntry>()));
}
/// <summary>Set the given directory as a snapshottable directory.</summary>
/// <remarks>
/// Set the given directory as a snapshottable directory.
/// If the path is already a snapshottable directory, update the quota.
/// </remarks>
/// <exception cref="System.IO.IOException"/>
public virtual void SetSnapshottable(string path, bool checkNestedSnapshottable)
{
INodesInPath iip = fsdir.GetINodesInPath4Write(path);
INodeDirectory d = INodeDirectory.ValueOf(iip.GetLastINode(), path);
if (checkNestedSnapshottable)
{
CheckNestedSnapshottable(d, path);
}
if (d.IsSnapshottable())
{
//The directory is already a snapshottable directory.
d.SetSnapshotQuota(DirectorySnapshottableFeature.SnapshotLimit);
}
else
{
d.AddSnapshottableFeature();
}
AddSnapshottable(d);
}
/// <summary>Check the replication for both the current file and all its prior snapshots
/// </summary>
/// <param name="currentFile">the Path of the current file</param>
/// <param name="snapshotRepMap">
/// A map maintaining all the snapshots of the current file, as well
/// as their expected replication number stored in their corresponding
/// INodes
/// </param>
/// <param name="expectedBlockRep">The expected replication number</param>
/// <exception cref="System.Exception"/>
private void CheckSnapshotFileReplication(Path currentFile, IDictionary <Path, short
> snapshotRepMap, short expectedBlockRep)
{
// First check the getBlockReplication for the INode of the currentFile
INodeFile inodeOfCurrentFile = GetINodeFile(currentFile);
NUnit.Framework.Assert.AreEqual(expectedBlockRep, inodeOfCurrentFile.GetBlockReplication
());
// Then check replication for every snapshot
foreach (Path ss in snapshotRepMap.Keys)
{
INodesInPath iip = fsdir.GetINodesInPath(ss.ToString(), true);
INodeFile ssInode = iip.GetLastINode().AsFile();
// The replication number derived from the
// INodeFileWithLink#getBlockReplication should always == expectedBlockRep
NUnit.Framework.Assert.AreEqual(expectedBlockRep, ssInode.GetBlockReplication());
// Also check the number derived from INodeFile#getFileReplication
NUnit.Framework.Assert.AreEqual(snapshotRepMap[ss], ssInode.GetFileReplication(iip
.GetPathSnapshotId()));
}
}
/// <summary>Create a snapshot of the given path.</summary>
/// <remarks>
/// Create a snapshot of the given path.
/// It is assumed that the caller will perform synchronization.
/// </remarks>
/// <param name="iip">the INodes resolved from the snapshottable directory's path</param>
/// <param name="snapshotName">The name of the snapshot.</param>
/// <exception cref="System.IO.IOException">
/// Throw IOException when 1) the given path does not lead to an
/// existing snapshottable directory, and/or 2) there exists a
/// snapshot with the given name for the directory, and/or 3)
/// snapshot number exceeds quota
/// </exception>
public virtual string CreateSnapshot(INodesInPath iip, string snapshotRoot, string
snapshotName)
{
INodeDirectory srcRoot = GetSnapshottableRoot(iip);
if (snapshotCounter == GetMaxSnapshotID())
{
// We have reached the maximum allowable snapshot ID and since we don't
// handle rollover we will fail all subsequent snapshot creation
// requests.
//
throw new SnapshotException("Failed to create the snapshot. The FileSystem has run out of "
+ "snapshot IDs and ID rollover is not supported.");
}
srcRoot.AddSnapshot(snapshotCounter, snapshotName);
//create success, update id
snapshotCounter++;
numSnapshots.GetAndIncrement();
return(Org.Apache.Hadoop.Hdfs.Server.Namenode.Snapshot.Snapshot.GetSnapshotPath(snapshotRoot
, snapshotName));
}
