org.apache.ignite.spi.discovery.tcp.ipfinder.kubernetes

Class TcpDiscoveryKubernetesIpFinder

java.lang.Object

org.apache.ignite.spi.discovery.tcp.ipfinder.TcpDiscoveryIpFinderAdapter

org.apache.ignite.spi.discovery.tcp.ipfinder.kubernetes.TcpDiscoveryKubernetesIpFinder

All Implemented Interfaces:

TcpDiscoveryIpFinder

public class TcpDiscoveryKubernetesIpFinder
extends TcpDiscoveryIpFinderAdapter

IP finder for automatic lookup of Ignite nodes running in Kubernetes environment. All Ignite nodes have to deployed as Kubernetes pods in order to be discovered. An application that uses Ignite client nodes as a gateway to the cluster is required to be containerized as well. Applications and Ignite nodes running outside of Kubernetes will not be able to reach the containerized counterparts.

The implementation is based on a distinct Kubernetes service that has to be created and should be deployed prior Ignite nodes startup. The service will maintain a list of all endpoints (internal IP addresses) of all containerized Ignite pods running so far. The name of the service must be equal to setServiceName(String) which is `ignite` by default.

As for Ignite pods, it's recommended to label them in such a way that the service will use the label in its selector configuration excluding endpoints of irrelevant Kubernetes pods running in parallel.

The IP finder, in its turn, will call this service to retrieve Ignite pods IP addresses. The port will be either the one that is set with TcpDiscoverySpi.setLocalPort(int) or TcpDiscoverySpi.DFLT_PORT. Make sure that all Ignite pods occupy a similar discovery port, otherwise they will not be able to discover each other using this IP finder.

Optional configuration

• The Kubernetes service name for IP addresses lookup (see setServiceName(String))
• The Kubernetes service namespace for IP addresses lookup (see setNamespace(String)
• The host name of the Kubernetes API server (see setMasterUrl(String))
• Path to the service token (see setAccountToken(String)

Both registerAddresses(Collection) and unregisterAddresses(Collection) have no effect.

Note, this IP finder is only workable when it used in Kubernetes environment. Choose another implementation of TcpDiscoveryIpFinder for local or home network tests.

Field Summary

Fields inherited from class org.apache.ignite.spi.discovery.tcp.ipfinder.TcpDiscoveryIpFinderAdapter

ignite

Constructor Summary

Constructors

Constructor and Description
TcpDiscoveryKubernetesIpFinder() Creates an instance of Kubernetes IP finder.

Method Summary

Modifier and Type	Method and Description
Collection<InetSocketAddress>	getRegisteredAddresses() Gets all addresses registered in this finder.
void	registerAddresses(Collection<InetSocketAddress> addrs) Registers new addresses.
void	setAccountToken(String accountToken) Specifies the path to the service token file.
void	setMasterUrl(String master) Sets the host name of the Kubernetes API server.
void	setNamespace(String namespace) Sets the namespace the Kubernetes service belongs to.
void	setServiceName(String service) Sets the name of Kubernetes service for Ignite pods' IP addresses lookup.
void	unregisterAddresses(Collection<InetSocketAddress> addrs) Unregisters provided addresses.

Methods inherited from class org.apache.ignite.spi.discovery.tcp.ipfinder.TcpDiscoveryIpFinderAdapter

close, discoveryClientMode, initializeLocalAddresses, isShared, onSpiContextDestroyed, onSpiContextInitialized, setShared, spiContext, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

TcpDiscoveryKubernetesIpFinder

public TcpDiscoveryKubernetesIpFinder()

Creates an instance of Kubernetes IP finder.

Method Detail

getRegisteredAddresses

public Collection<InetSocketAddress> getRegisteredAddresses()
                                                     throws IgniteSpiException

Gets all addresses registered in this finder.

Returns:

All known addresses, potentially empty, but never null.

Throws:

IgniteSpiException - In case of error.

registerAddresses

public void registerAddresses(Collection<InetSocketAddress> addrs)
                       throws IgniteSpiException

Registers new addresses.

Implementation should accept duplicates quietly, but should not register address if it is already registered.

Parameters:

addrs - Addresses to register. Not null and not empty.

Throws:

IgniteSpiException - In case of error.

unregisterAddresses

public void unregisterAddresses(Collection<InetSocketAddress> addrs)
                         throws IgniteSpiException

Unregisters provided addresses.

Implementation should accept addresses that are currently not registered quietly (just no-op).

Parameters:

addrs - Addresses to unregister. Not null and not empty.

Throws:

IgniteSpiException - In case of error.

setServiceName

public void setServiceName(String service)

Sets the name of Kubernetes service for Ignite pods' IP addresses lookup. The name of the service must be equal to the name set in service's Kubernetes configuration. If this parameter is not changed then the name of the service has to be set to 'ignite' in the corresponding Kubernetes configuration.

Parameters:

service - Kubernetes service name for IP addresses lookup. If it's not set then 'ignite' is used by default.

setNamespace

public void setNamespace(String namespace)

Sets the namespace the Kubernetes service belongs to. By default, it's supposed that the service is running under Kubernetes `default` namespace.

Parameters:

namespace - The Kubernetes service namespace for IP addresses lookup.

setMasterUrl

public void setMasterUrl(String master)

Sets the host name of the Kubernetes API server. By default the following host name is used: 'https://kubernetes.default.svc.cluster.local:443'.

Parameters:

master - The host name of the Kubernetes API server.

setAccountToken

public void setAccountToken(String accountToken)

Specifies the path to the service token file. By default the following account token is used: '/var/run/secrets/kubernetes.io/serviceaccount/token'.

Parameters:

accountToken - The path to the service token file.