Package io.hekate.cluster.seed.etcd

Class EtcdSeedNodeProvider

java.lang.Object

io.hekate.cluster.seed.etcd.EtcdSeedNodeProvider

All Implemented Interfaces:

SeedNodeProvider, ConfigReportSupport

public class EtcdSeedNodeProvider
extends Object
implements SeedNodeProvider, ConfigReportSupport

Etcd-based implementation of SeedNodeProvider interface.

This provider uses Etcd key-value store to keep track of active seed nodes.

When this provider start it registers the local node's address using the following key structure:
[base_path]/ [namespace]/ [node_address]

In order to find existing seed nodes this provider scans for keys that has the following prefix:
[base_path]/ [namespace]/

Please see the documentation of EtcdSeedNodeProviderConfig class for more details about the available configuration options.

See Also:

ClusterServiceFactory.setSeedNodeProvider(SeedNodeProvider), SeedNodeProvider

Constructor Summary

Constructors

Constructor	Description
EtcdSeedNodeProvider(EtcdSeedNodeProviderConfig cfg)	Constructs new instance.

Method Summary

Modifier and Type	Method	Description
String	basePath()	Returns the base path for storing seed nodes information in Etcd.
long	cleanupInterval()	Returns the time interval in milliseconds for the cluster service to perform the stale data cleaning.
List<URI>	endpoints()	Returns an immutable list of Etcd endpoints.
List<InetSocketAddress>	findSeedNodes(String namespace)	Returns the list of known seed node addresses.
void	registerRemote(String namespace, InetSocketAddress node)	Registered the specified addresses within this provider.
void	report(ConfigReporter report)	Report configuration.
void	startDiscovery(String namespace, InetSocketAddress node)	Registers the local node address and starts this provider.
void	stopDiscovery(String namespace, InetSocketAddress node)	Unregisters the local node address and stops this provider.
void	suspendDiscovery()	Suspends discovery activities.
String	toString()
void	unregisterRemote(String namespace, InetSocketAddress node)	Unregisters the specified address from this provider.

Methods inherited from class java.lang.Object

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

Constructor Detail

EtcdSeedNodeProvider

public EtcdSeedNodeProvider(EtcdSeedNodeProviderConfig cfg)

Constructs new instance.

Parameters:

cfg - Configuration.

Method Detail

report

public void report(ConfigReporter report)

Description copied from interface: ConfigReportSupport

Report configuration.

Specified by:

report in interface ConfigReportSupport

Parameters:

report - Reporter.

basePath

public String basePath()

Returns the base path for storing seed nodes information in Etcd.

Returns:

Base path for storing seed nodes information in Etcd.

See Also:

EtcdSeedNodeProviderConfig.setBasePath(String)

endpoints

public List<URI> endpoints()

Returns an immutable list of Etcd endpoints.

Returns:

immutable list of Etcd endpoints.

See Also:

EtcdSeedNodeProviderConfig.setEndpoints(List)

findSeedNodes

public List<InetSocketAddress> findSeedNodes(String namespace)
                                      throws HekateException

Description copied from interface: SeedNodeProvider

Returns the list of known seed node addresses.

Specified by:

findSeedNodes in interface SeedNodeProvider

Parameters:

namespace - Cluster namespace (see ClusterServiceFactory.setNamespace(String)).

Returns:

List of known seed node addresses.

Throws:

HekateException - if failed to provide seed node addresses information due to the system failure.

startDiscovery

public void startDiscovery(String namespace,
                           InetSocketAddress node)
                    throws HekateException

Description copied from interface: SeedNodeProvider

Registers the local node address and starts this provider.

Specified by:

startDiscovery in interface SeedNodeProvider

Parameters:

namespace - Cluster namespace (see ClusterServiceFactory.setNamespace(String)).

node - Local node address.

Throws:

HekateException - If failed to start discovery due to the system failure.

stopDiscovery

public void stopDiscovery(String namespace,
                          InetSocketAddress node)
                   throws HekateException

Description copied from interface: SeedNodeProvider

Unregisters the local node address and stops this provider.

Specified by:

stopDiscovery in interface SeedNodeProvider

Parameters:

namespace - Cluster namespace (see ClusterServiceFactory.setNamespace(String)).

node - Local node address.

Throws:

HekateException - If failed to stop discovery due to the system failure.

cleanupInterval

public long cleanupInterval()

Description copied from interface: SeedNodeProvider

Returns the time interval in milliseconds for the cluster service to perform the stale data cleaning. If the returned value if less than or equals to zero then stale data cleaning will be disabled.

Specified by:

cleanupInterval in interface SeedNodeProvider

Returns:

Time interval in milliseconds.

registerRemote

public void registerRemote(String namespace,
                           InetSocketAddress node)
                    throws HekateException

Description copied from interface: SeedNodeProvider

Registered the specified addresses within this provider.

This method is the part of a stale data cleanup activity and is performed by the cluster service if it detects that particular node is within its cluster topology but is not registered within this provider (i.e. not returned from SeedNodeProvider.findSeedNodes(String) method).

Specified by:

registerRemote in interface SeedNodeProvider

Parameters:

namespace - Cluster namespace (see ClusterServiceFactory.setNamespace(String)).

node - Node address that should be registered.

Throws:

HekateException - If node couldn't be registered due to the system failure.

unregisterRemote

public void unregisterRemote(String namespace,
                             InetSocketAddress node)
                      throws HekateException

Description copied from interface: SeedNodeProvider

Unregisters the specified address from this provider.

This method is the part of a stale data cleanup activity and is called by the cluster service if it detects that there is no cluster node running at the specified address while this address is still registered within this provider (i.e. is returned from SeedNodeProvider.findSeedNodes(String) method).

Specified by:

unregisterRemote in interface SeedNodeProvider

Parameters:

namespace - Cluster namespace (see ClusterServiceFactory.setNamespace(String)).

node - Node address that should be unregistered.

Throws:

HekateException - If node couldn't be unregistered due to the system failure.

suspendDiscovery

public void suspendDiscovery()
                      throws HekateException

Description copied from interface: SeedNodeProvider

Suspends discovery activities.

Specified by:

suspendDiscovery in interface SeedNodeProvider

Throws:

HekateException - If failed to suspend discovery activities due to some system failure.

toString

public String toString()

Overrides:

toString in class Object