org.apache.bookkeeper.client

Class TopologyAwareEnsemblePlacementPolicy.DNSResolverDecorator

java.lang.Object

org.apache.bookkeeper.client.TopologyAwareEnsemblePlacementPolicy.DNSResolverDecorator

All Implemented Interfaces:

org.apache.bookkeeper.net.DNSToSwitchMapping

Enclosing class:

TopologyAwareEnsemblePlacementPolicy

static class TopologyAwareEnsemblePlacementPolicy.DNSResolverDecorator
extends java.lang.Object
implements org.apache.bookkeeper.net.DNSToSwitchMapping

Decorator for any existing dsn resolver. Backfills returned data with appropriate default rack info.

Field Summary

Fields

Modifier and Type	Field and Description
(package private) java.util.function.Supplier<java.lang.String>	defaultRackSupplier
(package private) org.apache.bookkeeper.stats.Counter	failedToResolveNetworkLocationCounter
(package private) org.apache.bookkeeper.net.DNSToSwitchMapping	resolver

Constructor Summary

Constructors

Constructor and Description
DNSResolverDecorator(org.apache.bookkeeper.net.DNSToSwitchMapping resolver, java.util.function.Supplier<java.lang.String> defaultRackSupplier, org.apache.bookkeeper.stats.Counter failedToResolveNetworkLocationCounter)

Method Summary

Modifier and Type	Method and Description
void	reloadCachedMappings() Reload all of the cached mappings.
java.util.List<java.lang.String>	resolve(java.util.List<java.lang.String> names) Resolves a list of DNS-names/IP-addresses and returns back a list of switch information (network paths).
void	setBookieAddressResolver(org.apache.bookkeeper.proto.BookieAddressResolver bookieAddressResolver) Receives the current BookieAddressResolver.
boolean	useHostName() Hints what to use with implementation when InetSocketAddress is converted to String: hostname (addr.getHostName(), default) or IP address (addr.getAddress().getHostAddress()).

Methods inherited from class java.lang.Object

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

Field Detail

defaultRackSupplier

final java.util.function.Supplier<java.lang.String> defaultRackSupplier

resolver

final org.apache.bookkeeper.net.DNSToSwitchMapping resolver

failedToResolveNetworkLocationCounter

@StatsDoc(name="FAILED_TO_RESOLVE_NETWORK_LOCATION_TOTAL",
          help="total number of times Resolver failed to resolve rack information of a node")
final org.apache.bookkeeper.stats.Counter failedToResolveNetworkLocationCounter

Constructor Detail

DNSResolverDecorator

DNSResolverDecorator(org.apache.bookkeeper.net.DNSToSwitchMapping resolver,
                     java.util.function.Supplier<java.lang.String> defaultRackSupplier,
                     org.apache.bookkeeper.stats.Counter failedToResolveNetworkLocationCounter)

Method Detail

setBookieAddressResolver

public void setBookieAddressResolver(org.apache.bookkeeper.proto.BookieAddressResolver bookieAddressResolver)

Description copied from interface: org.apache.bookkeeper.net.DNSToSwitchMapping

Receives the current BookieAddressResolver.

Specified by:

setBookieAddressResolver in interface org.apache.bookkeeper.net.DNSToSwitchMapping

resolve

public java.util.List<java.lang.String> resolve(java.util.List<java.lang.String> names)

Description copied from interface: org.apache.bookkeeper.net.DNSToSwitchMapping

Resolves a list of DNS-names/IP-addresses and returns back a list of switch information (network paths). One-to-one correspondence must be maintained between the elements in the lists. Consider an element in the argument list - x.y.com. The switch information that is returned must be a network path of the form /foo/rack, where / is the root, and 'foo' is the switch where 'rack' is connected. Note the hostname/ip-address is not part of the returned path. The network topology of the cluster would determine the number of components in the network path.

If a name cannot be resolved to a rack, the implementation should return NetworkTopology.DEFAULT_REGION_AND_RACK. This is what the bundled implementations do, though it is not a formal requirement

Specified by:

resolve in interface org.apache.bookkeeper.net.DNSToSwitchMapping

Parameters:

names - the list of hosts to resolve (can be empty)

Returns:

list of resolved network paths. If names is empty, the returned list is also empty

useHostName

public boolean useHostName()

Description copied from interface: org.apache.bookkeeper.net.DNSToSwitchMapping

Hints what to use with implementation when InetSocketAddress is converted to String: hostname (addr.getHostName(), default) or IP address (addr.getAddress().getHostAddress()).

Specified by:

useHostName in interface org.apache.bookkeeper.net.DNSToSwitchMapping

Returns:

true if hostname, false if IP address. Default is true.

reloadCachedMappings

public void reloadCachedMappings()

Description copied from interface: org.apache.bookkeeper.net.DNSToSwitchMapping

Reload all of the cached mappings.

If there is a cache, this method will clear it, so that future accesses will get a chance to see the new data.

Specified by:

reloadCachedMappings in interface org.apache.bookkeeper.net.DNSToSwitchMapping