org.apache.hadoop.hbase.master.snapshot

Class RestoreSnapshotHandler

java.lang.Object

org.apache.hadoop.hbase.executor.EventHandler

org.apache.hadoop.hbase.master.handler.TableEventHandler

org.apache.hadoop.hbase.master.snapshot.RestoreSnapshotHandler

All Implemented Interfaces:

Comparable<Runnable>, Runnable, SnapshotSentinel

@InterfaceAudience.Private
public class RestoreSnapshotHandler
extends TableEventHandler
implements SnapshotSentinel

Handler to Restore a snapshot.

Uses RestoreSnapshotHelper to replace the table content with the data available in the snapshot.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.hbase.executor.EventHandler

EventHandler.EventHandlerListener

Field Summary

Fields inherited from class org.apache.hadoop.hbase.master.handler.TableEventHandler

masterServices, tableLock, tableName

Fields inherited from class org.apache.hadoop.hbase.executor.EventHandler

eventType, seqids, server, waitingTimeForEvents

Constructor Summary

Constructors

Constructor and Description
RestoreSnapshotHandler(MasterServices masterServices, HBaseProtos.SnapshotDescription snapshot, HTableDescriptor htd)

Method Summary

Methods

Modifier and Type	Method and Description
void	cancel(String why) Actively cancel a running snapshot.
protected void	completed(Throwable exception) Called after that process() is completed.
long	getCompletionTimestamp()
ForeignException	getExceptionIfFailed() Get the exception that caused the snapshot to fail, if the snapshot has failed.
HBaseProtos.SnapshotDescription	getSnapshot()
protected void	handleTableOperation(List<HRegionInfo> hris) The restore table is executed in place.
boolean	isFinished() Check to see if the snapshot is finished, where finished may be success or failure.
RestoreSnapshotHandler	prepare() Event handlers should do all the necessary checks in this method (rather than in the constructor, or in process()) so that the caller, which is mostly executed in the ipc context can fail fast.
void	rethrowExceptionIfFailed() Rethrow the exception returned by SnapshotSentinel.getExceptionIfFailed().

Methods inherited from class org.apache.hadoop.hbase.master.handler.TableEventHandler

getTableDescriptor, prepareWithTableLock, process, releaseTableLock, reOpenAllRegions

Methods inherited from class org.apache.hadoop.hbase.executor.EventHandler

compareTo, getEventType, getInformativeName, getListener, getPriority, getSeqid, handleException, run, setListener, toString

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

RestoreSnapshotHandler

public RestoreSnapshotHandler(MasterServices masterServices,
                      HBaseProtos.SnapshotDescription snapshot,
                      HTableDescriptor htd)
                       throws IOException

Throws:

IOException

Method Detail

prepare

public RestoreSnapshotHandler prepare()
                               throws IOException

Description copied from class: EventHandler

Event handlers should do all the necessary checks in this method (rather than in the constructor, or in process()) so that the caller, which is mostly executed in the ipc context can fail fast. Process is executed async from the client ipc, so this method gives a quick chance to do some basic checks. Should be called after constructing the EventHandler, and before process().

Overrides:

prepare in class TableEventHandler

Returns:

the instance of this class

Throws:

IOException

handleTableOperation

protected void handleTableOperation(List<HRegionInfo> hris)
                             throws IOException

The restore table is executed in place. - The on-disk data will be restored - reference files are put in place without moving data - [if something fail here: you need to delete the table and re-run the restore] - hbase:meta will be updated - [if something fail here: you need to run hbck to fix hbase:meta entries] The passed in list gets changed in this method

Specified by:

handleTableOperation in class TableEventHandler

Throws:

IOException

completed

protected void completed(Throwable exception)

Description copied from class: TableEventHandler

Called after that process() is completed.

Overrides:

completed in class TableEventHandler

Parameters:

exception - null if process() is successful or not null if something has failed.

isFinished

public boolean isFinished()

Description copied from interface: SnapshotSentinel

Check to see if the snapshot is finished, where finished may be success or failure.

Specified by:

isFinished in interface SnapshotSentinel

Returns:

false if the snapshot is still in progress, true if the snapshot has finished

getCompletionTimestamp

public long getCompletionTimestamp()

Specified by:

getCompletionTimestamp in interface SnapshotSentinel

Returns:

-1 if the snapshot is in progress, otherwise the completion timestamp.

getSnapshot

public HBaseProtos.SnapshotDescription getSnapshot()

Specified by:

getSnapshot in interface SnapshotSentinel

Returns:

the description of the snapshot being run

cancel

public void cancel(String why)

Description copied from interface: SnapshotSentinel

Actively cancel a running snapshot.

Specified by:

cancel in interface SnapshotSentinel

Parameters:

why - Reason for cancellation.

getExceptionIfFailed

public ForeignException getExceptionIfFailed()

Description copied from interface: SnapshotSentinel

Get the exception that caused the snapshot to fail, if the snapshot has failed.

Specified by:

getExceptionIfFailed in interface SnapshotSentinel

Returns:

ForeignException that caused the snapshot to fail, or null if the snapshot is still in progress or has succeeded

rethrowExceptionIfFailed

public void rethrowExceptionIfFailed()
                              throws ForeignException

Description copied from interface: SnapshotSentinel

Rethrow the exception returned by SnapshotSentinel.getExceptionIfFailed(). If there is no exception this is a no-op.

Specified by:

rethrowExceptionIfFailed in interface SnapshotSentinel

Throws:

ForeignException - all exceptions from remote sources are procedure exceptions