org.apache.hadoop.registry.server.dns

Class RegistryDNS

java.lang.Object

org.apache.hadoop.service.AbstractService

org.apache.hadoop.registry.server.dns.RegistryDNS

All Implemented Interfaces:

Closeable, AutoCloseable, DNSOperations, ZoneSelector, org.apache.hadoop.service.Service

public class RegistryDNS
extends org.apache.hadoop.service.AbstractService
implements DNSOperations, ZoneSelector

A DNS service reflecting the state of the YARN registry. Records are created based on service records available in the YARN ZK-based registry.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	RegistryDNS.CloseableLock An implementation allowing for obtaining and releasing a lock.

Nested classes/interfaces inherited from interface org.apache.hadoop.service.Service

org.apache.hadoop.service.Service.STATE

Field Summary

Fields

Modifier and Type	Field and Description
static String	CONTAINER
static String	IN_ADDR_ARPA
static String	ZONE_SUFFIX

Constructor Summary

Constructors

Constructor and Description
RegistryDNS(String name) Construct the service.

Method Summary

Modifier and Type	Method and Description
void	addNIOTCP(InetAddress addr, int port) Create the thread (Callable) monitoring the TCP listener.
void	addNIOUDP(InetAddress addr, int port) Create the thread monitoring the socket for inbound UDP requests.
protected void	addSplitReverseZones(org.apache.hadoop.conf.Configuration conf, int subnetCount) Create the zones based on the zone count.
void	delete(String path, ServiceRecord record) Delete the DNS records generated by the provided service record.
byte[]	errorMessage(org.xbill.DNS.Message query, int rcode) Generate an error message based on inbound query.
org.xbill.DNS.Zone	findBestZone(org.xbill.DNS.Name name) Find the zone that correlates to the provided name.
org.xbill.DNS.RRset	findExactMatch(org.xbill.DNS.Name name, int type) Find the record set that matches the requested name and type.
byte[]	formErrorMessage(byte[] in) Creates a DNS error response.
protected org.xbill.DNS.Record[]	getRecords(org.xbill.DNS.Name name, int type) Requests records for the given resource name.
protected org.xbill.DNS.Name	getReverseZoneName(org.apache.hadoop.conf.Configuration conf) Returns the list of reverse lookup zones.
protected int	getZoneCount() Return the number of zones in the map.
void	initializeChannels(org.apache.hadoop.conf.Configuration conf)
void	nioTCPClient(SocketChannel ch) Process a TCP request.
void	register(String path, ServiceRecord record) Register DNS records based on the provided service record.
void	serveNIOTCP(ServerSocketChannel serverSocketChannel, InetAddress addr, int port) Monitor the TCP socket for inbound requests.
protected void	serviceInit(org.apache.hadoop.conf.Configuration conf) Initializes the registry.
protected void	serviceStop() Stops the registry.
protected void	setDNSSECEnabled(org.apache.hadoop.conf.Configuration conf) Set the value of the DNSSEC enabled property.
protected void	stopExecutor() Shuts down the leveraged executor service.

Methods inherited from class org.apache.hadoop.service.AbstractService

close, getBlockers, getConfig, getFailureCause, getFailureState, getLifecycleHistory, getName, getServiceState, getStartTime, init, isInState, noteFailure, putBlocker, registerGlobalListener, registerServiceListener, removeBlocker, serviceStart, setConfig, start, stop, toString, unregisterGlobalListener, unregisterServiceListener, waitForServiceToStop

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.hadoop.service.Service

close, getBlockers, getConfig, getFailureCause, getFailureState, getLifecycleHistory, getName, getServiceState, getStartTime, init, isInState, registerServiceListener, start, stop, unregisterServiceListener, waitForServiceToStop

Field Detail

CONTAINER

public static final String CONTAINER

See Also:

Constant Field Values

IN_ADDR_ARPA

public static final String IN_ADDR_ARPA

See Also:

Constant Field Values

ZONE_SUFFIX

public static final String ZONE_SUFFIX

See Also:

Constant Field Values

Constructor Detail

RegistryDNS

public RegistryDNS(String name)

Construct the service.

Parameters:

name - service name

Method Detail

initializeChannels

public void initializeChannels(org.apache.hadoop.conf.Configuration conf)
                        throws Exception

Throws:

Exception

serviceInit

protected void serviceInit(org.apache.hadoop.conf.Configuration conf)
                    throws Exception

Initializes the registry.

Overrides:

serviceInit in class org.apache.hadoop.service.AbstractService

Parameters:

conf - the hadoop configuration

Throws:

Exception - if there are tcp/udp issues

getZoneCount

protected int getZoneCount()

Return the number of zones in the map.

Returns:

number of zones in the map

addSplitReverseZones

protected void addSplitReverseZones(org.apache.hadoop.conf.Configuration conf,
                                    int subnetCount)
                             throws IOException

Create the zones based on the zone count.

Parameters:

conf - the Hadoop configuration.

subnetCount - number of subnets to create reverse zones for.

Throws:

IOException - if the DNSSEC key can not be read.

getReverseZoneName

protected org.xbill.DNS.Name getReverseZoneName(org.apache.hadoop.conf.Configuration conf)

Returns the list of reverse lookup zones.

Parameters:

conf - the hadoop configuration.

Returns:

the list of reverse zone names required based on the configuration properties.

setDNSSECEnabled

protected void setDNSSECEnabled(org.apache.hadoop.conf.Configuration conf)

Set the value of the DNSSEC enabled property.

Parameters:

conf - the Hadoop configuration.

serviceStop

protected void serviceStop()
                    throws Exception

Stops the registry.

Overrides:

serviceStop in class org.apache.hadoop.service.AbstractService

Throws:

Exception - if the service stop generates an issue.

stopExecutor

protected void stopExecutor()

Shuts down the leveraged executor service.

formErrorMessage

public byte[] formErrorMessage(byte[] in)

Creates a DNS error response.

Parameters:

in - the byte array detailing the error.

Returns:

the error message, in bytes

nioTCPClient

public void nioTCPClient(SocketChannel ch)
                  throws IOException

Process a TCP request.

Parameters:

ch - the socket channel for the request.

Throws:

IOException - if the tcp processing generates an issue.

serveNIOTCP

public void serveNIOTCP(ServerSocketChannel serverSocketChannel,
                        InetAddress addr,
                        int port)
                 throws Exception

Monitor the TCP socket for inbound requests.

Parameters:

serverSocketChannel - the server socket channel

addr - the local inet address

port - the listener (local) port

Throws:

Exception - if the tcp processing fails.

addNIOTCP

public void addNIOTCP(InetAddress addr,
                      int port)
               throws Exception

Create the thread (Callable) monitoring the TCP listener.

Parameters:

addr - host address.

port - host port.

Throws:

Exception - if the tcp listener generates an error.

addNIOUDP

public void addNIOUDP(InetAddress addr,
                      int port)
               throws Exception

Create the thread monitoring the socket for inbound UDP requests.

Parameters:

addr - host address.

port - host port.

Throws:

Exception - if the UDP listener creation generates an error.

errorMessage

public byte[] errorMessage(org.xbill.DNS.Message query,
                           int rcode)

Generate an error message based on inbound query.

Parameters:

query - the query.

rcode - the response code for the specific error.

Returns:

the error message.

getRecords

protected org.xbill.DNS.Record[] getRecords(org.xbill.DNS.Name name,
                                            int type)

Requests records for the given resource name.

Parameters:

name - - query string

type - - type of DNS record to lookup

Returns:

DNS records

findExactMatch

public org.xbill.DNS.RRset findExactMatch(org.xbill.DNS.Name name,
                                          int type)

Find the record set that matches the requested name and type.

Parameters:

name - the requested name.

type - the record type.

Returns:

the set of records with the given name and type.

findBestZone

public org.xbill.DNS.Zone findBestZone(org.xbill.DNS.Name name)

Find the zone that correlates to the provided name.

Specified by:

findBestZone in interface ZoneSelector

Parameters:

name - the name to be matched to a zone.

Returns:

the zone.

register

public void register(String path,
                     ServiceRecord record)
              throws IOException

Register DNS records based on the provided service record.

Specified by:

register in interface DNSOperations

Parameters:

path - the ZK path of the service record.

record - record providing DNS registration info.

Throws:

IOException - if registration causes an error.

delete

public void delete(String path,
                   ServiceRecord record)
            throws IOException

Delete the DNS records generated by the provided service record.

Specified by:

delete in interface DNSOperations

Parameters:

path - the ZK path for the given record.

record - the service record

Throws:

IOException - if deletion causes and error.