Package org.apache.druid.segment.metadata

Class NoopSegmentSchemaCache

java.lang.Object

org.apache.druid.segment.metadata.SegmentSchemaCache

org.apache.druid.segment.metadata.NoopSegmentSchemaCache

public class NoopSegmentSchemaCache
extends SegmentSchemaCache

No-op implementation of SegmentSchemaCache that always returns false for isEnabled() and isInitialized().

Constructor Summary

Constructors

Constructor	Description
NoopSegmentSchemaCache()

Method Summary

Modifier and Type	Method	Description
void	addRealtimeSegmentSchema(SegmentId segmentId, SchemaPayloadPlus schema)	Adds schema for a realtime segment to the cache.
void	addSchemaPendingBackfill(SegmentId segmentId, SchemaPayloadPlus schema)	Adds a temporary schema for the given segment ID to the cache.
void	awaitInitialization()	CoordinatorSegmentMetadataCache startup waits on the cache initialization.
Map<String,SchemaPayload>	getPublishedSchemaPayloadMap()
Map<SegmentId,SegmentMetadata>	getPublishedSegmentMetadataMap()
Map<String,Integer>	getStats()
boolean	isEnabled()
boolean	isInitialized()
boolean	isSchemaCached(SegmentId segmentId)	Check if the cache contains schema for the given segment ID.
void	markSchemaPersisted(SegmentId segmentId)	Marks the schema for the given segment ID as persisted to the DB.
void	onLeaderStop()	This method is called when the current node is no longer the leader.
void	realtimeSegmentRemoved(SegmentId segmentId)	Removes schema for realtime segment.
void	resetSchemaForPublishedSegments(Map<SegmentId,SegmentMetadata> usedSegmentIdToMetadata, Map<String,SchemaPayload> schemaFingerprintToPayload)	Resets the schema in the cache for published (non-realtime) segments.
void	segmentRemoved(SegmentId segmentId)	Removes schema cached for this segment ID.
void	setInitialized()

Methods inherited from class org.apache.druid.segment.metadata.SegmentSchemaCache

getSchemaForSegment

Methods inherited from class java.lang.Object

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

Constructor Details

NoopSegmentSchemaCache

public NoopSegmentSchemaCache()

Method Details

isEnabled

public boolean isEnabled()

Overrides:

isEnabled in class SegmentSchemaCache

Returns:

true if schema caching is enabled.

setInitialized

public void setInitialized()

Overrides:

setInitialized in class SegmentSchemaCache

onLeaderStop

public void onLeaderStop()

Description copied from class: SegmentSchemaCache

This method is called when the current node is no longer the leader. The schema is cleared except for realtimeSegmentSchemaMap. Realtime schema continues to be updated on both the leader and follower nodes.

Overrides:

onLeaderStop in class SegmentSchemaCache

isInitialized

public boolean isInitialized()

Overrides:

isInitialized in class SegmentSchemaCache

awaitInitialization

public void awaitInitialization()
                         throws InterruptedException

Description copied from class: SegmentSchemaCache

CoordinatorSegmentMetadataCache startup waits on the cache initialization. This is being done to ensure that we don't execute metadata query for segment with schema already present in the DB.

Overrides:

awaitInitialization in class SegmentSchemaCache

Throws:

InterruptedException

resetSchemaForPublishedSegments

public void resetSchemaForPublishedSegments(Map<SegmentId,SegmentMetadata> usedSegmentIdToMetadata,
 Map<String,SchemaPayload> schemaFingerprintToPayload)

Description copied from class: SegmentSchemaCache

Resets the schema in the cache for published (non-realtime) segments. This method is called after each successful poll of used segments and schemas from the metadata store.

Overrides:

resetSchemaForPublishedSegments in class SegmentSchemaCache

Parameters:

usedSegmentIdToMetadata - Map from used segment ID to corresponding metadata

schemaFingerprintToPayload - Map from schema fingerprint to payload

addRealtimeSegmentSchema

public void addRealtimeSegmentSchema(SegmentId segmentId,
 SchemaPayloadPlus schema)

Description copied from class: SegmentSchemaCache

Adds schema for a realtime segment to the cache.

Overrides:

addRealtimeSegmentSchema in class SegmentSchemaCache

addSchemaPendingBackfill

public void addSchemaPendingBackfill(SegmentId segmentId,
 SchemaPayloadPlus schema)

Description copied from class: SegmentSchemaCache

Adds a temporary schema for the given segment ID to the cache. This schema is typically fetched from data nodes by issuing segment metadata queries. Once this schema is persisted to DB, call SegmentSchemaCache.markSchemaPersisted(org.apache.druid.timeline.SegmentId).

Overrides:

addSchemaPendingBackfill in class SegmentSchemaCache

markSchemaPersisted

public void markSchemaPersisted(SegmentId segmentId)

Description copied from class: SegmentSchemaCache

Marks the schema for the given segment ID as persisted to the DB.

Overrides:

markSchemaPersisted in class SegmentSchemaCache

getPublishedSegmentMetadataMap

public Map<SegmentId,SegmentMetadata> getPublishedSegmentMetadataMap()

Overrides:

getPublishedSegmentMetadataMap in class SegmentSchemaCache

Returns:

Immutable map from segment ID to SegmentMetadata for all published used segments currently present in this cache.

isSchemaCached

public boolean isSchemaCached(SegmentId segmentId)

Description copied from class: SegmentSchemaCache

Check if the cache contains schema for the given segment ID.

Overrides:

isSchemaCached in class SegmentSchemaCache

getPublishedSchemaPayloadMap

public Map<String,SchemaPayload> getPublishedSchemaPayloadMap()

Overrides:

getPublishedSchemaPayloadMap in class SegmentSchemaCache

Returns:

Immutable map from schema fingerprint to SchemaPayload for all schema fingerprints currently present in this cache.

segmentRemoved

public void segmentRemoved(SegmentId segmentId)

Description copied from class: SegmentSchemaCache

Removes schema cached for this segment ID.

Overrides:

segmentRemoved in class SegmentSchemaCache

realtimeSegmentRemoved

public void realtimeSegmentRemoved(SegmentId segmentId)

Description copied from class: SegmentSchemaCache

Removes schema for realtime segment.

Overrides:

realtimeSegmentRemoved in class SegmentSchemaCache

getStats

public Map<String,Integer> getStats()

Overrides:

getStats in class SegmentSchemaCache

Returns:

Summary stats of the current contents of the cache.