/**
* Delete the specified snapshot
*
* @param snapshot
* @throws SnapshotDoesNotExistException If the specified snapshot does not exist.
* @throws IOException For filesystem IOExceptions
*/
public void deleteSnapshot(SnapshotDescription snapshot)
throws SnapshotDoesNotExistException, IOException {
// check to see if it is completed
if (!isSnapshotCompleted(snapshot)) {
throw new SnapshotDoesNotExistException(ProtobufUtil.createSnapshotDesc(snapshot));
}
String snapshotName = snapshot.getName();
// first create the snapshot description and check to see if it exists
FileSystem fs = master.getMasterFileSystem().getFileSystem();
Path snapshotDir = SnapshotDescriptionUtils.getCompletedSnapshotDir(snapshotName, rootDir);
// Get snapshot info from file system. The one passed as parameter is a "fake" snapshotInfo with
// just the "name" and it does not contains the "real" snapshot information
snapshot = SnapshotDescriptionUtils.readSnapshotInfo(fs, snapshotDir);
// call coproc pre hook
MasterCoprocessorHost cpHost = master.getMasterCoprocessorHost();
if (cpHost != null) {
cpHost.preDeleteSnapshot(snapshot);
}
LOG.debug("Deleting snapshot: " + snapshotName);
// delete the existing snapshot
if (!fs.delete(snapshotDir, true)) {
throw new HBaseSnapshotException("Failed to delete snapshot directory: " + snapshotDir);
}
// call coproc post hook
if (cpHost != null) {
cpHost.postDeleteSnapshot(snapshot);
}
}
/**
* @param snapshot descriptor of the snapshot to take
* @param masterServices master services provider
*/
public TakeSnapshotHandler(SnapshotDescription snapshot, final MasterServices masterServices) {
super(masterServices, EventType.C_M_SNAPSHOT_TABLE);
assert snapshot != null : "SnapshotDescription must not be nul1";
assert masterServices != null : "MasterServices must not be nul1";
this.master = masterServices;
this.snapshot = snapshot;
this.snapshotTable = TableName.valueOf(snapshot.getTable());
this.conf = this.master.getConfiguration();
this.fs = this.master.getMasterFileSystem().getFileSystem();
this.rootDir = this.master.getMasterFileSystem().getRootDir();
this.snapshotDir = SnapshotDescriptionUtils.getCompletedSnapshotDir(snapshot, rootDir);
this.workingDir = SnapshotDescriptionUtils.getWorkingSnapshotDir(snapshot, rootDir);
this.monitor = new ForeignExceptionDispatcher(snapshot.getName());
this.snapshotManifest = SnapshotManifest.create(conf, fs, workingDir, snapshot, monitor);
this.tableLockManager = master.getTableLockManager();
this.tableLock =
this.tableLockManager.writeLock(snapshotTable, EventType.C_M_SNAPSHOT_TABLE.toString());
// prepare the verify
this.verifier = new MasterSnapshotVerifier(masterServices, snapshot, rootDir);
// update the running tasks
this.status =
TaskMonitor.get()
.createStatus("Taking " + snapshot.getType() + " snapshot on table: " + snapshotTable);
}
/**
* Check to see if the snapshot is one of the currently completed snapshots Returns true if the
* snapshot exists in the "completed snapshots folder".
*
* @param snapshot expected snapshot to check
* @return <tt>true</tt> if the snapshot is stored on the {@link FileSystem}, <tt>false</tt> if is
* not stored
* @throws IOException if the filesystem throws an unexpected exception,
* @throws IllegalArgumentException if snapshot name is invalid.
*/
private boolean isSnapshotCompleted(SnapshotDescription snapshot) throws IOException {
try {
final Path snapshotDir = SnapshotDescriptionUtils.getCompletedSnapshotDir(snapshot, rootDir);
FileSystem fs = master.getMasterFileSystem().getFileSystem();
// check to see if the snapshot already exists
return fs.exists(snapshotDir);
} catch (IllegalArgumentException iae) {
throw new UnknownSnapshotException("Unexpected exception thrown", iae);
}
}
/**
* Restore or Clone the specified snapshot
*
* @param reqSnapshot
* @param nonceGroup unique value to prevent duplicated RPC
* @param nonce unique value to prevent duplicated RPC
* @throws IOException
*/
public long restoreOrCloneSnapshot(
SnapshotDescription reqSnapshot, final long nonceGroup, final long nonce) throws IOException {
FileSystem fs = master.getMasterFileSystem().getFileSystem();
Path snapshotDir = SnapshotDescriptionUtils.getCompletedSnapshotDir(reqSnapshot, rootDir);
// check if the snapshot exists
if (!fs.exists(snapshotDir)) {
LOG.error("A Snapshot named '" + reqSnapshot.getName() + "' does not exist.");
throw new SnapshotDoesNotExistException(ProtobufUtil.createSnapshotDesc(reqSnapshot));
}
// Get snapshot info from file system. The reqSnapshot is a "fake" snapshotInfo with
// just the snapshot "name" and table name to restore. It does not contains the "real" snapshot
// information.
SnapshotDescription snapshot = SnapshotDescriptionUtils.readSnapshotInfo(fs, snapshotDir);
SnapshotManifest manifest =
SnapshotManifest.open(master.getConfiguration(), fs, snapshotDir, snapshot);
HTableDescriptor snapshotTableDesc = manifest.getTableDescriptor();
TableName tableName = TableName.valueOf(reqSnapshot.getTable());
// stop tracking "abandoned" handlers
cleanupSentinels();
// Verify snapshot validity
SnapshotReferenceUtil.verifySnapshot(master.getConfiguration(), fs, manifest);
// Execute the restore/clone operation
long procId;
if (MetaTableAccessor.tableExists(master.getConnection(), tableName)) {
procId =
restoreSnapshot(reqSnapshot, tableName, snapshot, snapshotTableDesc, nonceGroup, nonce);
} else {
procId =
cloneSnapshot(reqSnapshot, tableName, snapshot, snapshotTableDesc, nonceGroup, nonce);
}
return procId;
}