org.apache.directory.mitosis.service
Class ReplicationInterceptor

java.lang.Object
  org.apache.directory.server.core.interceptor.BaseInterceptor
      org.apache.directory.mitosis.service.ReplicationInterceptor

All Implemented Interfaces:

Interceptor

public class ReplicationInterceptor
extends BaseInterceptor

An Interceptor that intercepts LDAP operations and propagates the changes occurred by the operations into other ReplicaIds so the DIT of each ReplicaId in the cluster has the same content without any conflict.

Once an operation is invoked, this interceptor transforms it into one or more operations that makes the requested operation more proper and robust for replication. The transformation process is actually just calling a respective factory method in OperationFactory. The methods in OperationFactory returns a new Operation instance.

The newly created Operation is used for three purposes.

• To perform the requested operation to the local PartitionNexus
• To store the created Operation itself to ReplicationStore so that it can be retrieved later by ReplicationLogCleanJob and ReplicationClientContextHandler
• To transfer itself to other ReplicaIds via TCP/IP communication between ReplicationClientContextHandler and ReplicationServerContextHandler

The first two actions (modifying the local DIT and storing the Operation to ReplicationStore) are performed automatically when Operation#execute(PartitionNexus, ReplicationStore, Registries) method is invoked. ReplicationInterceptor always call it instead of forwarding the requested operation to the next Interceptor.

The last action takes place by ReplicationClientContextHandler, which handles TCP/IP connection managed by ClientConnectionManager.

There are two special attributes in the entries to be replicated:

• entryCSN - stores CSN of the entry. This attribute is used to compare the incoming operation from other replica is still valid. If the local entryCSN value is bigger then that of the incoming operation, it means conflict, and therefore an appropriate conflict resolution mechanism should get engaged.
• entryDeleted - is TRUE if and only if the entry is deleted. The entry is not deleted immediately by a delete operation because entryCSN attribute should be retained for certain amount of time to determine whether the incoming change LOG, which affects an entry with the same DN, is a conflict (modification on a deleted entry) or not (creation of a new entry). You can purge old deleted entries and related change logs in ReplicationStore by calling purgeAgedData(), or they will be purged automatically by periodic manner as you configured with ReplicationConfiguration. by calling ReplicationConfiguration.setLogMaxAge(int). Because of this attribute, lookup and search operations are overrided to ignore entries with entryDeleted set to TRUE.

Version:

$Rev$, $Date$

Author:

The Apache Directory Project (dev@directory.apache.org)

XBean

Field Summary

static java.lang.String

DEFAULT_SERVICE_NAME The service name

Constructor Summary

ReplicationInterceptor()
Creates a new instance of ReplicationInterceptor.

Method Summary

void	add(NextInterceptor nextInterceptor, AddOperationContext addContext) Filters Partition.add( AddOperationContext ) call.
void	delete(NextInterceptor next, DeleteOperationContext deleteContext) Filters Partition.delete( DeleteOperationContext ) call.
void	destroy() This method does nothing by default.
ReplicationConfiguration	getConfiguration()
DirectoryService	getDirectoryService()
java.lang.String	getName() This interceptor has configuration so it might be useful to allow several instances in a chain.
boolean	hasEntry(NextInterceptor nextInterceptor, EntryOperationContext entryContext) Filters Partition.hasEntry( EntryOperationContext ) call.
void	init(DirectoryService directoryService) Initialize the Replication service.
void	interruptConnectors() Wake the sleeping (unconnected) replicas.
EntryFilteringCursor	list(NextInterceptor nextInterceptor, ListOperationContext opContext) Filters Partition.list( ListOperationContext ) call.
ClonedServerEntry	lookup(NextInterceptor nextInterceptor, LookupOperationContext lookupContext) Filters Partition.lookup( LookupOperationContext ) call.
void	modify(NextInterceptor next, ModifyOperationContext modifyContext) Filters Partition.modify( ModifyOperationContext ) call.
void	move(NextInterceptor next, MoveOperationContext moveOpContext) Filters Partition.move( MoveOperationContext ) call.
void	moveAndRename(NextInterceptor next, MoveAndRenameOperationContext moveAndRenameOpContext) Filters Partition.moveAndRename( MoveAndRenameOperationContext) call.
void	purgeAgedData() Purges old replication logs and the old entries marked as 'deleted' (i.e.
void	rename(NextInterceptor next, RenameOperationContext renameOpContext) Filters Partition.rename( RenameOperationContext ) call.
void	replicate() Forces this context to send replication data to the peer replica immediately.
EntryFilteringCursor	search(NextInterceptor nextInterceptor, SearchOperationContext opContext) Filters Partition.search( SearchOperationContext ) call.
void	setConfiguration(ReplicationConfiguration configuration)
void	setName(java.lang.String name) Set the name for this service instance

Methods inherited from class org.apache.directory.server.core.interceptor.BaseInterceptor

addContextPartition, bind, compare, getContext, getMatchedName, getPrincipal, getRootDSE, getSuffix, listSuffixes, removeContextPartition, unbind

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_SERVICE_NAME

public static final java.lang.String DEFAULT_SERVICE_NAME

The service name

See Also:

Constant Field Values

Constructor Detail

ReplicationInterceptor

public ReplicationInterceptor()

Creates a new instance of ReplicationInterceptor.

Method Detail

getName

public java.lang.String getName()

This interceptor has configuration so it might be useful to allow several instances in a chain.

Specified by:

getName in interface Interceptor

Overrides:

getName in class BaseInterceptor

Returns:

configured name for this interceptor.

setName

public void setName(java.lang.String name)

Set the name for this service instance

Parameters:

name - The new name

getConfiguration

public ReplicationConfiguration getConfiguration()

setConfiguration

public void setConfiguration(ReplicationConfiguration configuration)

init

public void init(DirectoryService directoryService)
          throws java.lang.Exception

Initialize the Replication service. We have to check that the configuration is valid, initialize a store for pending operations, and start the communication with the other LDAP servers.

Specified by:

init in interface Interceptor

Overrides:

init in class BaseInterceptor

Parameters:

directoryService - the DirectoryService instance

Throws:

java.lang.Exception

destroy

public void destroy()

Description copied from class: BaseInterceptor

This method does nothing by default.

Specified by:

destroy in interface Interceptor

Overrides:

destroy in class BaseInterceptor

replicate

public void replicate()

Forces this context to send replication data to the peer replica immediately.

interruptConnectors

public void interruptConnectors()

Wake the sleeping (unconnected) replicas.

purgeAgedData

public void purgeAgedData()
                   throws java.lang.Exception

Purges old replication logs and the old entries marked as 'deleted' (i.e. Constants.ENTRY_DELETED is TRUE). This method should be called periodically to make sure the size of the DIT and ReplicationStore increase limitlessly.

Throws:

javax.naming.NamingException - on error

java.lang.Exception

See Also:

ReplicationConfiguration.setLogMaxAge(int), ReplicationLogCleanJob

add

public void add(NextInterceptor nextInterceptor,
                AddOperationContext addContext)
         throws java.lang.Exception

Description copied from interface: Interceptor

Filters Partition.add( AddOperationContext ) call.

Specified by:

add in interface Interceptor

Overrides:

add in class BaseInterceptor

Throws:

java.lang.Exception

delete

public void delete(NextInterceptor next,
                   DeleteOperationContext deleteContext)
            throws java.lang.Exception

Description copied from interface: Interceptor

Filters Partition.delete( DeleteOperationContext ) call.

Specified by:

delete in interface Interceptor

Overrides:

delete in class BaseInterceptor

Throws:

java.lang.Exception

modify

public void modify(NextInterceptor next,
                   ModifyOperationContext modifyContext)
            throws java.lang.Exception

Description copied from interface: Interceptor

Filters Partition.modify( ModifyOperationContext ) call.

Specified by:

modify in interface Interceptor

Overrides:

modify in class BaseInterceptor

Throws:

java.lang.Exception

move

public void move(NextInterceptor next,
                 MoveOperationContext moveOpContext)
          throws java.lang.Exception

Description copied from interface: Interceptor

Filters Partition.move( MoveOperationContext ) call.

Specified by:

move in interface Interceptor

Overrides:

move in class BaseInterceptor

Throws:

java.lang.Exception

moveAndRename

public void moveAndRename(NextInterceptor next,
                          MoveAndRenameOperationContext moveAndRenameOpContext)
                   throws java.lang.Exception

Description copied from interface: Interceptor

Filters Partition.moveAndRename( MoveAndRenameOperationContext) call.

Specified by:

moveAndRename in interface Interceptor

Overrides:

moveAndRename in class BaseInterceptor

Throws:

java.lang.Exception

rename

public void rename(NextInterceptor next,
                   RenameOperationContext renameOpContext)
            throws java.lang.Exception

Description copied from interface: Interceptor

Filters Partition.rename( RenameOperationContext ) call.

Specified by:

rename in interface Interceptor

Overrides:

rename in class BaseInterceptor

Throws:

java.lang.Exception

hasEntry

public boolean hasEntry(NextInterceptor nextInterceptor,
                        EntryOperationContext entryContext)
                 throws java.lang.Exception

Description copied from interface: Interceptor

Filters Partition.hasEntry( EntryOperationContext ) call.

Specified by:

hasEntry in interface Interceptor

Overrides:

hasEntry in class BaseInterceptor

Throws:

java.lang.Exception

lookup

public ClonedServerEntry lookup(NextInterceptor nextInterceptor,
                                LookupOperationContext lookupContext)
                         throws java.lang.Exception

Description copied from interface: Interceptor

Filters Partition.lookup( LookupOperationContext ) call.

Specified by:

lookup in interface Interceptor

Overrides:

lookup in class BaseInterceptor

Throws:

java.lang.Exception

list

public EntryFilteringCursor list(NextInterceptor nextInterceptor,
                                 ListOperationContext opContext)
                          throws java.lang.Exception

Description copied from interface: Interceptor

Filters Partition.list( ListOperationContext ) call.

Specified by:

list in interface Interceptor

Overrides:

list in class BaseInterceptor

Throws:

java.lang.Exception

search

public EntryFilteringCursor search(NextInterceptor nextInterceptor,
                                   SearchOperationContext opContext)
                            throws java.lang.Exception

Description copied from interface: Interceptor

Filters Partition.search( SearchOperationContext ) call.

Specified by:

search in interface Interceptor

Overrides:

search in class BaseInterceptor

Throws:

java.lang.Exception

getDirectoryService

public DirectoryService getDirectoryService()