org.apache.ignite.internal.processors.cache.persistence.snapshot

Class AbstractSnapshotVerificationTask

java.lang.Object

org.apache.ignite.compute.ComputeTaskAdapter<SnapshotPartitionsVerifyTaskArg,SnapshotPartitionsVerifyTaskResult>

org.apache.ignite.internal.processors.cache.persistence.snapshot.AbstractSnapshotVerificationTask

All Implemented Interfaces:

Serializable, ComputeTask<SnapshotPartitionsVerifyTaskArg,SnapshotPartitionsVerifyTaskResult>

Direct Known Subclasses:

IncrementalSnapshotVerificationTask, SnapshotHandlerRestoreTask, SnapshotPartitionsVerifyTask

public abstract class AbstractSnapshotVerificationTask
extends ComputeTaskAdapter<SnapshotPartitionsVerifyTaskArg,SnapshotPartitionsVerifyTaskResult>

The task for checking the consistency of snapshots in the cluster.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected IgniteEx	ignite Ignite instance.
protected Map<ClusterNode,List<SnapshotMetadata>>	metas Map of snapshot metadata information found on each cluster node.

Constructor Summary

Constructors

Constructor and Description
AbstractSnapshotVerificationTask()

Method Summary

Modifier and Type	Method and Description
static void	checkMissedMetadata(Collection<SnapshotMetadata> clusterMetas) Ensures that all parts of the snapshot are available according to the metadata.
protected abstract ComputeJob	createJob(String name, @Nullable String path, int incIdx, String constId, Collection<String> groups, boolean check)
Map<ComputeJob,ClusterNode>	map(List<ClusterNode> subgrid, SnapshotPartitionsVerifyTaskArg arg) This method is called to map or split grid task into multiple grid jobs.
ComputeJobResultPolicy	result(ComputeJobResult res, List<ComputeJobResult> rcvd) Default implementation which will wait for all jobs to complete before calling ComputeTask.reduce(List) method.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.ignite.compute.ComputeTask

reduce

Field Detail

metas

protected final Map<ClusterNode,List<SnapshotMetadata>> metas

Map of snapshot metadata information found on each cluster node.

ignite

@IgniteInstanceResource
protected IgniteEx ignite

Ignite instance.

Constructor Detail

AbstractSnapshotVerificationTask

public AbstractSnapshotVerificationTask()

Method Detail

map

public Map<ComputeJob,ClusterNode> map(List<ClusterNode> subgrid,
                                       SnapshotPartitionsVerifyTaskArg arg)

This method is called to map or split grid task into multiple grid jobs. This is the first method that gets called when task execution starts.

Parameters:

subgrid - Nodes available for this task execution. Note that order of nodes is guaranteed to be randomized by container. This ensures that every time you simply iterate through grid nodes, the order of nodes will be random which over time should result into all nodes being used equally.

arg - Task execution argument. Can be null. This is the same argument as the one passed into Grid#execute(...) methods.

Returns:

Map of grid jobs assigned to subgrid node. Unless ComputeTaskContinuousMapper is injected into task, if null or empty map is returned, exception will be thrown.

result

public ComputeJobResultPolicy result(ComputeJobResult res,
                                     List<ComputeJobResult> rcvd)
                              throws IgniteException

Default implementation which will wait for all jobs to complete before calling ComputeTask.reduce(List) method.

If remote job resulted in exception (ComputeJobResult.getException() is not null), then ComputeJobResultPolicy.FAILOVER policy will be returned if the exception is instance of ClusterTopologyException or ComputeExecutionRejectedException, which means that remote node either failed or job execution was rejected before it got a chance to start. In all other cases the exception will be rethrown which will ultimately cause task to fail.

Specified by:

result in interface ComputeTask<SnapshotPartitionsVerifyTaskArg,SnapshotPartitionsVerifyTaskResult>

Overrides:

result in class ComputeTaskAdapter<SnapshotPartitionsVerifyTaskArg,SnapshotPartitionsVerifyTaskResult>

Parameters:

res - Received remote grid executable result.

rcvd - All previously received results.

Returns:

Result policy that dictates how to process further upcoming job results.

Throws:

IgniteException - If handling a job result caused an error effectively rejecting a failover. This exception will be thrown out of ComputeTaskFuture.get() method.

checkMissedMetadata

public static void checkMissedMetadata(Collection<SnapshotMetadata> clusterMetas)
                                throws IgniteCheckedException

Ensures that all parts of the snapshot are available according to the metadata.

Parameters:

clusterMetas - List of snapshot metadata found in the cluster.

Throws:

IgniteCheckedException - If some metadata is missing.

createJob

protected abstract ComputeJob createJob(String name,
                                        @Nullable
                                        @Nullable String path,
                                        int incIdx,
                                        String constId,
                                        Collection<String> groups,
                                        boolean check)

Parameters:

name - Snapshot name.

path - Snapshot directory path.

incIdx - Incremental snapshot index.

constId - Snapshot metadata file name.

groups - Cache groups to be restored from the snapshot. May be empty if all cache groups are being restored.

check - If true check snapshot before restore.

Returns:

Compute job.