org.threadly.db.aurora

Class AuroraClusterMonitor

java.lang.Object

org.threadly.db.aurora.AuroraClusterMonitor

public class AuroraClusterMonitor
extends java.lang.Object

Class which monitors a "cluster" of aurora servers. It is expected that for each given cluster there is exactly one master server, and zero or more secondary servers which can be used for reads. This class will monitor those clusters, providing a monitor through getMonitor(Set).

Currently there is no way to stop monitoring a cluster. So changes (both additions and removals) of aurora clusters will currently need a JVM restart in order to have the new monitoring behave correctly.

Method Summary

Modifier and Type	Method and Description
void	expediteServerCheck(AuroraServer auroraServer) Indicate a given server should be expedited in checking its current state.
AuroraServer	getCurrentMaster() Returns the current cluster master which can accept writes.
static AuroraClusterMonitor	getMonitor(java.util.Set<AuroraServer> servers) Return a monitor instance for a given set of servers.
AuroraServer	getRandomReadReplica() Return a random read only replica server.

Methods inherited from class java.lang.Object

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

Method Detail

getMonitor

public static AuroraClusterMonitor getMonitor(java.util.Set<AuroraServer> servers)

Return a monitor instance for a given set of servers. This instance will be consistent as long as an equivalent servers set is provided.

Parameters:

servers - Set of servers within the cluster

Returns:

Monitor to select healthy and well balanced cluster servers

getRandomReadReplica

public AuroraServer getRandomReadReplica()

Return a random read only replica server.

Returns:

Random read only replica server, or null if no servers are healthy

getCurrentMaster

public AuroraServer getCurrentMaster()

Returns the current cluster master which can accept writes. May be null if there is not currently any healthy cluster members which can accept writes.

Returns:

Current writable server or null if no known one exists

expediteServerCheck

public void expediteServerCheck(AuroraServer auroraServer)

Indicate a given server should be expedited in checking its current state. If a given connection finds issues with a suggested server informing the monitor of the issues can ensure that everyone using this cluster can be informed of the state quicker.

Parameters:

auroraServer - Server identifier to be checked