Package org.apache.pulsar.broker.service

Class HashRangeAutoSplitStickyKeyConsumerSelector

java.lang.Object

org.apache.pulsar.broker.service.HashRangeAutoSplitStickyKeyConsumerSelector

All Implemented Interfaces:

StickyKeyConsumerSelector

public class HashRangeAutoSplitStickyKeyConsumerSelector
extends Object
implements StickyKeyConsumerSelector

This is a consumer selector based fixed hash range. 1.Each consumer serves a fixed range of hash value 2.The whole range of hash value could be covered by all the consumers. 3.Once a consumer is removed, the left consumers could still serve the whole range. Initializing with a fixed hash range, by default 2 >> 15. First consumer added, hash range looks like: 0 -< 65536(consumer-1) Second consumer added, will find a biggest range to split: 0 -< 32768(consumer-2) -< 65536(consumer-1) While a consumer removed, The range for this consumer will be taken over by other consumer, consumer-2 removed: 0 -< 65536(consumer-1) In this approach use skip list map to maintain the hash range and consumers. Select consumer will return the ceiling key of message key hashcode % range size.

Field Summary

Fields inherited from interface org.apache.pulsar.broker.service.StickyKeyConsumerSelector

DEFAULT_RANGE_SIZE, STICKY_KEY_HASH_NOT_SET

Constructor Summary

Constructors

Constructor	Description
HashRangeAutoSplitStickyKeyConsumerSelector()
HashRangeAutoSplitStickyKeyConsumerSelector(boolean addOrRemoveReturnsImpactedConsumersResult)
HashRangeAutoSplitStickyKeyConsumerSelector(int rangeSize, boolean addOrRemoveReturnsImpactedConsumersResult)

Method Summary

Modifier and Type	Method	Description
CompletableFuture<Optional<ImpactedConsumersResult>>	addConsumer(Consumer consumer)	Add a new consumer.
ConsumerHashAssignmentsSnapshot	getConsumerHashAssignmentsSnapshot()	Get the current mappings of hash range to consumer.
org.apache.pulsar.client.api.Range	getKeyHashRange()	Get the full range of hash values used by this selector.
Optional<ImpactedConsumersResult>	removeConsumer(Consumer consumer)	Remove the consumer.
Consumer	select(int hash)	Select a consumer by hash.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.pulsar.broker.service.StickyKeyConsumerSelector

getConsumerKeyHashRanges, makeStickyKeyHash, select

Constructor Details

HashRangeAutoSplitStickyKeyConsumerSelector

public HashRangeAutoSplitStickyKeyConsumerSelector()

HashRangeAutoSplitStickyKeyConsumerSelector

public HashRangeAutoSplitStickyKeyConsumerSelector(boolean addOrRemoveReturnsImpactedConsumersResult)

HashRangeAutoSplitStickyKeyConsumerSelector

public HashRangeAutoSplitStickyKeyConsumerSelector(int rangeSize,
 boolean addOrRemoveReturnsImpactedConsumersResult)

Method Details

addConsumer

public CompletableFuture<Optional<ImpactedConsumersResult>> addConsumer(Consumer consumer)

Description copied from interface: StickyKeyConsumerSelector

Add a new consumer.

Specified by:

addConsumer in interface StickyKeyConsumerSelector

Parameters:

consumer - the new consumer to be added

Returns:

a CompletableFuture that completes with the result of impacted consumers. The result contains information about the existing consumers whose hash ranges were affected by the addition of the new consumer.

removeConsumer

public Optional<ImpactedConsumersResult> removeConsumer(Consumer consumer)

Description copied from interface: StickyKeyConsumerSelector

Remove the consumer.

Specified by:

removeConsumer in interface StickyKeyConsumerSelector

Parameters:

consumer - the consumer to be removed

Returns:

the result of impacted consumers. The result contains information about the existing consumers whose hash ranges were affected by the removal of the consumer.

select

public Consumer select(int hash)

Description copied from interface: StickyKeyConsumerSelector

Select a consumer by hash.

Specified by:

select in interface StickyKeyConsumerSelector

Parameters:

hash - the hash corresponding to the sticky key

Returns:

the selected consumer

getKeyHashRange

public org.apache.pulsar.client.api.Range getKeyHashRange()

Description copied from interface: StickyKeyConsumerSelector

Get the full range of hash values used by this selector. The upper bound is exclusive.

Specified by:

getKeyHashRange in interface StickyKeyConsumerSelector

Returns:

the full range of hash values

getConsumerHashAssignmentsSnapshot

public ConsumerHashAssignmentsSnapshot getConsumerHashAssignmentsSnapshot()

Description copied from interface: StickyKeyConsumerSelector

Get the current mappings of hash range to consumer.

Specified by:

getConsumerHashAssignmentsSnapshot in interface StickyKeyConsumerSelector

Returns:

a snapshot of the consumer hash assignments