Package org.apache.solr.core.snapshots

Class SolrSnapshotMetaDataManager

java.lang.Object

org.apache.solr.core.snapshots.SolrSnapshotMetaDataManager

public class SolrSnapshotMetaDataManager
extends Object

This class is responsible to manage the persistent snapshots meta-data for the Solr indexes. The persistent snapshots are implemented by relying on Lucene IndexDeletionPolicy abstraction to configure a specific IndexCommit to be retained. The IndexDeletionPolicyWrapper in Solr uses this class to create/delete the Solr index snapshots.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	SolrSnapshotMetaDataManager.SnapshotMetaData	A class defining the meta-data for a specific snapshot.

Field Summary

Fields

Modifier and Type	Field	Description
protected Map<String,SolrSnapshotMetaDataManager.SnapshotMetaData>	nameToDetailsMapping	Used to map snapshot name to snapshot meta-data.
static String	SNAPSHOT_METADATA_DIR
static String	SNAPSHOTS_PREFIX	Prefix used for the save file.

Constructor Summary

Constructors

Constructor	Description
SolrSnapshotMetaDataManager(SolrCore solrCore, org.apache.lucene.store.Directory dir)	A constructor.
SolrSnapshotMetaDataManager(SolrCore solrCore, org.apache.lucene.store.Directory dir, org.apache.lucene.index.IndexWriterConfig.OpenMode mode)	A constructor.

Method Summary

Modifier and Type	Method	Description
Optional<org.apache.lucene.index.IndexCommit>	getIndexCommitByName(String commitName)	This method returns the IndexCommit associated with the specified commitName .
Optional<SolrSnapshotMetaDataManager.SnapshotMetaData>	getSnapshotMetaData(String name)	This method returns the snapshot meta-data for the specified name (if it exists).
org.apache.lucene.store.Directory	getSnapshotsDir()
boolean	isSnapshotted(long genNumber)	This method returns if snapshot is created for the specified generation number in the *current* index directory.
boolean	isSnapshotted(String indexDirPath, long genNumber)	This method returns if snapshot is created for the specified generation number in the specified index directory.
List<String>	listSnapshots()
Collection<SolrSnapshotMetaDataManager.SnapshotMetaData>	listSnapshotsInIndexDir(String indexDirPath)	This method returns a list of snapshots created in a specified index directory.
Optional<SolrSnapshotMetaDataManager.SnapshotMetaData>	release(String name)	This method deletes a previously created snapshot (if any).
void	snapshot(String name, String indexDirPath, long gen)	This method creates a new snapshot meta-data entry.

Methods inherited from class java.lang.Object

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

Field Detail

SNAPSHOT_METADATA_DIR

public static final String SNAPSHOT_METADATA_DIR

See Also:

Constant Field Values

SNAPSHOTS_PREFIX

public static final String SNAPSHOTS_PREFIX

Prefix used for the save file.

See Also:

Constant Field Values

nameToDetailsMapping

protected final Map<String,SolrSnapshotMetaDataManager.SnapshotMetaData> nameToDetailsMapping

Used to map snapshot name to snapshot meta-data.

Constructor Detail

SolrSnapshotMetaDataManager

public SolrSnapshotMetaDataManager(SolrCore solrCore,
                                   org.apache.lucene.store.Directory dir)
                            throws IOException

A constructor.

Parameters:

dir - The directory where the snapshot meta-data should be stored. Enables updating the existing meta-data.

Throws:

IOException - in case of errors.

SolrSnapshotMetaDataManager

public SolrSnapshotMetaDataManager(SolrCore solrCore,
                                   org.apache.lucene.store.Directory dir,
                                   org.apache.lucene.index.IndexWriterConfig.OpenMode mode)
                            throws IOException

A constructor.

Parameters:

dir - The directory where the snapshot meta-data is stored.

mode - CREATE If previous meta-data should be erased. APPEND If previous meta-data should be read and updated. CREATE_OR_APPEND Creates a new meta-data structure if one does not exist Updates the existing structure if one exists.

Throws:

IOException - in case of errors.

Method Detail

getSnapshotsDir

public org.apache.lucene.store.Directory getSnapshotsDir()

Returns:

The snapshot meta-data directory

snapshot

public void snapshot(String name,
                     String indexDirPath,
                     long gen)
              throws IOException

This method creates a new snapshot meta-data entry.

Parameters:

name - The name of the snapshot.

indexDirPath - The directory path where the index files are stored.

gen - The generation number for the IndexCommit being snapshotted.

Throws:

IOException - in case of I/O errors.

release

public Optional<SolrSnapshotMetaDataManager.SnapshotMetaData> release(String name)
                                                               throws IOException

This method deletes a previously created snapshot (if any).

Parameters:

name - The name of the snapshot to be deleted.

Returns:

The snapshot meta-data if the snapshot with the snapshot name exists.

Throws:

IOException - in case of I/O error

isSnapshotted

public boolean isSnapshotted(long genNumber)

This method returns if snapshot is created for the specified generation number in the *current* index directory.

Parameters:

genNumber - The generation number for the IndexCommit to be checked.

Returns:

true if the snapshot is created. false otherwise.

isSnapshotted

public boolean isSnapshotted(String indexDirPath,
                             long genNumber)

This method returns if snapshot is created for the specified generation number in the specified index directory.

Parameters:

genNumber - The generation number for the IndexCommit to be checked.

Returns:

true if the snapshot is created. false otherwise.

getSnapshotMetaData

public Optional<SolrSnapshotMetaDataManager.SnapshotMetaData> getSnapshotMetaData(String name)

This method returns the snapshot meta-data for the specified name (if it exists).

Parameters:

name - The name of the snapshot

Returns:

The snapshot meta-data if exists.

listSnapshots

public List<String> listSnapshots()

Returns:

A list of snapshots created so far.

listSnapshotsInIndexDir

public Collection<SolrSnapshotMetaDataManager.SnapshotMetaData> listSnapshotsInIndexDir(String indexDirPath)

This method returns a list of snapshots created in a specified index directory.

Parameters:

indexDirPath - The index directory path.

Returns:

a list snapshots stored in the specified directory.

getIndexCommitByName

public Optional<org.apache.lucene.index.IndexCommit> getIndexCommitByName(String commitName)
                                                                   throws IOException

This method returns the IndexCommit associated with the specified commitName . A snapshot with specified commitName must be created before invoking this method.

Parameters:

commitName - The name of persisted commit

Returns:

the IndexCommit

Throws:

IOException - in case of I/O error.