org.hawkular.alerts.engine.service

Interface PartitionTriggerListener

All Known Implementing Classes:

AlertsEngineImpl

public interface PartitionTriggerListener

A listener for reacting to partition events related to triggers. We have two main types of partition events: - Trigger changes: node-a changes a trigger that is being computed in node-c, so in this case a partition event is sent to make node-c reload/remove trigger depending of the type of operation (add, update, remove). - Partition changes: a topology is re-configured adding/removing nodes, in this case, a partition could re-organize the triggers across nodes. A node receive a list of old entries, and new entries to maintain the existing ones, remove the moved entries and reload the new ones.

Author:

Jay Shaughnessy, Lucas Ponce

Method Summary

Modifier and Type	Method and Description
void	onPartitionChange(Map<String,List<String>> partition, Map<String,List<String>> removed, Map<String,List<String>> added) Invoked when the topology has changed in the partition.
void	onTriggerChange(PartitionManager.Operation operation, String tenantId, String triggerId) Invoked on the node that holds the trigger when a trigger has been added, modified or removed.

Method Detail

onTriggerChange

void onTriggerChange(PartitionManager.Operation operation,
                     String tenantId,
                     String triggerId)

Invoked on the node that holds the trigger when a trigger has been added, modified or removed.

Parameters:

operation - the operation performed on the Trigger

tenantId - Tenant where Trigger is stored

triggerId - Trigger id

onPartitionChange

void onPartitionChange(Map<String,List<String>> partition,
                       Map<String,List<String>> removed,
                       Map<String,List<String>> added)

Invoked when the topology has changed in the partition. It updates the local partition after re-calculate triggers distribution across the partition. A local partition has the following structure: Map>: { "tenant1": ["trigger1","trigger2","trigger3"], "tenant2": ["trigger4","trigger5","trigger6"] }

Parameters:

partition - a Map with the local partition of triggers hold by this node after calculation

removed - a Map with the triggers removed from an old partition after calculation

added - a Map with the triggers added from an old partition after calculation