/*
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* The contents of this file are subject to the terms of the Common Development and
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* Distribution License (the License). You may not use this file except in compliance with the
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* License.
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*
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* You can obtain a copy of the License at legal/CDDLv1.0.txt. See the License for the
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* specific language governing permission and limitations under the License.
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*
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* When distributing Covered Software, include this CDDL Header Notice in each file and include
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* the License file at legal/CDDLv1.0.txt. If applicable, add the following below the CDDL
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* Header, with the fields enclosed by brackets [] replaced by your own identifying
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* information: "Portions Copyright [year] [name of copyright owner]".
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*
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* Copyright 2007-2009 Sun Microsystems, Inc.
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* Portions Copyright 2013-2016 ForgeRock AS.
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* Portions Copyright 2026 3A Systems, LLC.
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*/
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package org.opends.server.replication.plugin;
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import java.util.Iterator;
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import java.util.NoSuchElementException;
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import java.util.SortedMap;
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import java.util.SortedSet;
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import java.util.TreeMap;
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import java.util.TreeSet;
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import java.util.concurrent.ConcurrentHashMap;
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import java.util.concurrent.ConcurrentMap;
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import java.util.concurrent.ConcurrentSkipListSet;
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import java.util.concurrent.locks.ReentrantLock;
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import java.util.concurrent.locks.ReentrantReadWriteLock;
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import net.jcip.annotations.GuardedBy;
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import org.forgerock.opendj.ldap.DN;
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import org.opends.server.core.AddOperation;
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import org.opends.server.core.DeleteOperation;
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import org.opends.server.core.ModifyDNOperationBasis;
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import org.opends.server.core.ModifyOperation;
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import org.opends.server.replication.common.CSN;
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import org.opends.server.replication.common.ServerState;
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import org.opends.server.replication.protocol.AddMsg;
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import org.opends.server.replication.protocol.DeleteMsg;
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import org.opends.server.replication.protocol.LDAPUpdateMsg;
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import org.opends.server.replication.protocol.ModifyDNMsg;
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import org.opends.server.replication.protocol.ModifyMsg;
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import org.opends.server.replication.protocol.OperationContext;
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import org.opends.server.types.Operation;
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/**
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* This class is used to store the list of remote changes received
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* from a replication server and that are either currently being replayed
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* or that are waiting for being replayed.
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*
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* It is used to know when the ServerState must be updated and to compute
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* the dependencies between operations.
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*
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* One of this object is instantiated for each ReplicationDomain.
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*/
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final class RemotePendingChanges
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{
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/** A map used to store the pending changes. */
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@GuardedBy("pendingChangesLock")
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private final SortedMap<CSN, PendingChange> pendingChanges = new TreeMap<>();
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/**
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* A sorted set containing the list of PendingChanges that have
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* not been replayed correctly because they are dependent on
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* another change to be completed.
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*/
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@GuardedBy("dependentChangesLock")
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private final SortedSet<PendingChange> dependentChanges = new TreeSet<>();
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/**
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* {@code activeAndDependentChanges} also contains changes discovered to be dependent
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* on currently in progress changes.
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*/
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private final ConcurrentSkipListSet<PendingChange> activeAndDependentChanges = new ConcurrentSkipListSet<>();
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/**
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* The change each replay thread is replaying right now, read by the give-back on the way
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* out of a replay which was unwound.
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* <p>
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* It is an index of what {@link PendingChange#isOwnedBy(Thread)} already says rather than
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* a second copy of it: it is written in the same locked step wherever a change is taken
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* over or given back, and every road which acts on what it answers checks the ownership
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* of the change again. What it buys is the read. That read is made on a road an
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* {@code OutOfMemoryError} leads to, and looking the change up by walking the pending
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* changes takes two locks and allocates an iterator - an allocation a JVM which has just
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* refused one may well refuse again, and the change would then be left listed,
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* uncommitted and owned by a thread which is not replaying it anymore, which is the wedge
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* this issue is about (issue #922).
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* <p>
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* A thread is entered here when it takes a change over and removed when it gives it back,
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* applies it, or parks it as waiting for another change - the parked ones are handed to
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* whichever thread clears what they wait for, so they are not this one's to give back.
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* <p>
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* The entry of a thread is written by that thread and by nobody else, and that - not the
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* lock - is what keeps the writes apart: the park in {@link #addDependency(PendingChange)}
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* clears it under the read lock, where every other writer holds the write lock, and it
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* races nothing for it. {@link #clear()} is the one writer of every entry, and it holds
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* both locks.
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*/
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private final ConcurrentMap<Thread, CSN> changeBeingReplayed = new ConcurrentHashMap<>();
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private final ReentrantReadWriteLock pendingChangesLock = new ReentrantReadWriteLock(true);
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private final ReentrantReadWriteLock.ReadLock pendingChangesReadLock = pendingChangesLock.readLock();
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private final ReentrantReadWriteLock.WriteLock pendingChangesWriteLock = pendingChangesLock.writeLock();
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private final ReentrantLock dependentChangesLock = new ReentrantLock();
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/** The ServerState that will be updated when LDAPUpdateMsg are fully replayed. */
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private final ServerState state;
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/**
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* How many of the changes listed here have a replay failure recorded against them.
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* <p>
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* A change is counted from its first failed replay until it leaves this map, and it is
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* what tells a change which can not be applied from a backend which is serving again:
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* an outage fails everything in flight, while a change which can never be applied here
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* fails alone, among changes which replay perfectly well. The session restart backoff
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* reads it, so that the successful replays which surround a failing change do not keep
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* resetting the wait this domain has reached on it (issue #889).
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*/
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@GuardedBy("pendingChangesLock")
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private int failingChanges;
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/**
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* Creates a new RemotePendingChanges using the provided ServerState.
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*
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* @param state The ServerState that will be updated when LDAPUpdateMsg
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* have been fully replayed.
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*/
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public RemotePendingChanges(ServerState state)
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{
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this.state = state;
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}
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/**
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* Returns the number of changes waiting to be replayed.
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*
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* @return The number of changes waiting to be replayed
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*/
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public int getQueueSize()
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{
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pendingChangesReadLock.lock();
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try
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{
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return pendingChanges.size();
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}
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finally
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{
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pendingChangesReadLock.unlock();
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}
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}
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/**
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* Returns the number of changes actively being replayed.
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* <p>
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* A change whose replay failed counts here until it is applied or given up on: it stays
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* a dependency of the changes which follow it, since a change which is not in the data
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* is exactly what they must wait for, and the delivery which comes next takes it over.
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*
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* @return the number of changes actively being replayed.
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*/
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public int changesInProgressSize()
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{
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return activeAndDependentChanges.size();
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}
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/**
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* Returns the number of changes depending on other changes.
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*
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* @return the number of changes depending on other changes.
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*/
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public int getDependentChangesSize()
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{
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dependentChangesLock.lock();
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try
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{
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return dependentChanges.size();
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}
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finally
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{
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dependentChangesLock.unlock();
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}
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}
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/**
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* Add a new LDAPUpdateMsg that was received from the replication server
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* to the pendingList.
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* <p>
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* A change which is already listed and which a replay thread owns - it is being
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* replayed, it waits for the change it depends on, or it has been replayed and waits
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* for the changes before it - is left alone: that copy knows what this one does not,
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* and replaying it again is exactly what the duplicate check is there to prevent
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* (OPENDJ-1115).
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* <p>
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* A change which is listed but which no replay thread owns is taken over by this
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* delivery: it is the one to replay, and the copy which may still wait in the replay
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* queue is dropped by {@link #markInProgress(LDAPUpdateMsg)}. That is a change whose
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* replay failed - it is deliberately left out of the ServerState, so the replication
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* server sends it again over the session which was restarted (issue #889) - and it is
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* also, harmlessly, a change which was listed a moment ago by a delivery no replay
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* thread has picked up yet: the two deliveries carry the same change, and the last one
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* listed is the one replayed.
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* <p>
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* The failures the change went through are kept, whichever delivery replays it: they
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* are what has this replica eventually give up on a change it can not apply.
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*
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* @param update The LDAPUpdateMsg that was received from the replication
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* server and that will be added to the pending list.
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* @return {@code false} if the update was already registered in the pending
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* changes and is owned by a replay thread.
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*/
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public boolean putRemoteUpdate(LDAPUpdateMsg update)
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{
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pendingChangesWriteLock.lock();
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try
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{
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final CSN csn = update.getCSN();
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final PendingChange listed = pendingChanges.get(csn);
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if (listed == null)
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{
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pendingChanges.put(csn, new PendingChange(csn, null, update));
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return true;
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}
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if (listed.isCommitted() || listed.isOwned())
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{
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return false;
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}
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listed.setMsg(update);
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return true;
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}
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finally
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{
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pendingChangesWriteLock.unlock();
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}
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}
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/**
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* Mark an update message as committed.
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* <p>
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* A change another replay thread owns is not this thread's to record: it is reported as
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* a change which is not here, the way one which is not listed anymore is. A thread
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* decides that a change is in the data, or that it is to be given up on, and records
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* that decision a turn of this lock later - long enough for the change to have been
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* handed back, delivered again and taken over in between. Recording it then would
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* advance the ServerState over a change which is not in the data yet (issue #889) and
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* have the thread which is applying it right now fail to commit.
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* <p>
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* The give-back on the way out of an unwound replay is what makes this reachable: it
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* runs wherever the replay was left, so the checks which keep it from taking a change
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* away from the thread which owns it now belong on every road which reads ownership,
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* not only on {@link #replayFailed(CSN)} (issue #922).
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*
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* @param csn
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* The CSN of the update message that must be set as committed.
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* @throws NoSuchElementException
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* if there is no change with that CSN for this thread to record: it is not
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* listed as pending anymore, or another replay thread owns it
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*/
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public void commit(CSN csn)
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{
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pendingChangesWriteLock.lock();
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try
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{
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PendingChange curChange = pendingChanges.get(csn);
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if (curChange == null
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|| (curChange.isOwned() && !curChange.isOwnedBy(Thread.currentThread())))
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{
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throw new NoSuchElementException();
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}
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curChange.setCommitted(true);
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curChange.setOwner(null);
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changeBeingReplayed.remove(Thread.currentThread(), csn);
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activeAndDependentChanges.remove(curChange);
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final Iterator<PendingChange> it = pendingChanges.values().iterator();
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while (it.hasNext())
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{
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PendingChange pendingChange = it.next();
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if (!pendingChange.isCommitted())
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{
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break;
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}
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if (pendingChange.getMsg().contributesToDomainState())
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{
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state.update(pendingChange.getCSN());
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}
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if (pendingChange.getReplayFailures() > 0)
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{
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// The change is leaving this map, so it is not one of the failing ones anymore.
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failingChanges--;
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}
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it.remove();
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}
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}
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finally
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{
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pendingChangesWriteLock.unlock();
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}
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}
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/**
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* Gives up the ownership a replay thread had on the change with the provided CSN,
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* whose replay failed.
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* <p>
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* The change stays listed here and stays uncommitted: it is the barrier which keeps
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* the ServerState - and every change which follows it - from moving past a change
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* which is not in the data (issue #889), and it is what has the replication server
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* send it again over the restarted session. Only the mark which says a replay thread
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* owns it is dropped, so that {@link #putRemoteUpdate(LDAPUpdateMsg)} takes the next
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* delivery instead of discarding it as a duplicate.
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* <p>
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* It also stays listed among the changes the newer ones are checked against: a change
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* which is not in the data yet is exactly what the changes which follow it must depend
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* on, whether or not a replay thread owns it right now.
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* <p>
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* The changes another replay thread is applying right now are left alone: they are
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* about to commit, and forgetting them would have their {@code commit()} fail, the
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* ServerState stay behind them and the replication server replay them a second time.
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* <p>
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* Only the thread which owns the change gives it back. A release which arrives from
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* another one is a release of a change which has been taken over since - the failure of
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* a delivery is reported after the change it carried was handed to the delivery which
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* follows it - and taking the change away from the thread which is replaying it right
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* now is the double replay the ownership is there to prevent (issue #922).
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*
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* @param csn the CSN of the change whose replay failed
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*/
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public void replayFailed(CSN csn)
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{
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pendingChangesWriteLock.lock();
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try
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{
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final PendingChange change = pendingChanges.get(csn);
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if (change != null && !change.isCommitted() && change.isOwnedBy(Thread.currentThread()))
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{
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change.setOwner(null);
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changeBeingReplayed.remove(Thread.currentThread(), csn);
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}
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}
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finally
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{
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pendingChangesWriteLock.unlock();
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}
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}
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/** How long, and how many times, the replay of one change has been failing. */
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static final class ReplayFailure
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{
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private final int attempts;
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private final long failingForMs;
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private ReplayFailure(int attempts, long failingForMs)
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{
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this.attempts = attempts;
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this.failingForMs = failingForMs;
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}
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/**
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* Returns how many deliveries of the change failed to replay it in a row. A delivery
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* is attempted several times in place before it is counted here, so this is a count
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* of deliveries rather than of attempts made on the backend.
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*
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* @return the number of failed deliveries, at least 1
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*/
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int getAttempts()
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{
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return attempts;
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}
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/**
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* Returns how long the replay of the change has been failing, that is the time
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* between its first failure and the one which was just recorded.
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*
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* @return the duration in milliseconds, 0 for a first failure
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*/
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long getFailingForMs()
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{
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return failingForMs;
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}
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}
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/**
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* Records that the replay of the change with the provided CSN failed once more.
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* <p>
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* The failures are kept on the change itself, which stays listed for as long as it has
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* not been applied, so a change which keeps failing keeps its give-up budget across the
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* deliveries which take over from one another, and a change which is replayed or given
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* up on takes its failures away with it (issue #889).
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*
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* @param csn
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* the CSN of the change whose replay failed
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* @param nowMs
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* when it failed, on a clock which only moves forward
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* @return the failures of the change, or {@code null} when there is no change left here
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* for this thread to give up on: it is not listed as an uncommitted change
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* anymore, which happens when the domain was disabled while it was being
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* replayed, or another replay thread owns it, which is that change having been
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* delivered again and taken over while this thread was on its way to reporting
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* on it. Spending the give-up budget of a change another thread is applying
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* would have this replica skip a change which is being written (issue #922)
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*/
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public ReplayFailure recordReplayFailure(CSN csn, long nowMs)
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{
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pendingChangesWriteLock.lock();
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try
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{
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final PendingChange change = pendingChanges.get(csn);
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if (change == null || change.isCommitted()
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|| (change.isOwned() && !change.isOwnedBy(Thread.currentThread())))
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{
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return null;
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}
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if (change.getReplayFailures() == 0)
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{
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// Its first failure: this change joins the ones which are failing right now.
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failingChanges++;
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}
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change.recordReplayFailure(nowMs);
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return new ReplayFailure(change.getReplayFailures(), change.getReplayFailingForMs(nowMs));
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}
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finally
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{
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pendingChangesWriteLock.unlock();
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}
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}
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/**
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* Returns whether the replay of any change listed here is failing right now.
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* <p>
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* A change is failing from its first failed replay until it leaves this map, whether
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* it leaves it applied or given up on. The session restart backoff reads this: a
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* change which was replayed only says that this backend is serving again when it is
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* the last one which was failing, and the successful replays which surround a change
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* this replica can not apply must not keep resetting the wait it has reached on it.
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*
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* @return {@code true} while at least one listed change has a failed replay recorded
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* against it
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*/
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boolean hasFailingChanges()
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{
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pendingChangesReadLock.lock();
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try
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{
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return failingChanges > 0;
|
}
|
finally
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{
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pendingChangesReadLock.unlock();
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}
|
}
|
|
/**
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* Returns how many of the listed changes have a failed replay recorded against them.
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* <p>
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* A change is counted from its first failed replay until it leaves this map, whether it
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* leaves it applied or given up on. It is what tells that the replay of this domain is
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* stuck: a domain whose {@code replay-give-up-delay} is unlimited never gives up, so it
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* never counts a failed change either, and the changes it keeps asking for are only
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* visible here.
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*
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* @return the number of listed changes with a failed replay recorded against them
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*/
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public int getFailingChangesSize()
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{
|
pendingChangesReadLock.lock();
|
try
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{
|
return failingChanges;
|
}
|
finally
|
{
|
pendingChangesReadLock.unlock();
|
}
|
}
|
|
/**
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* Forgets every change listed here, without updating the ServerState.
|
* <p>
|
* Called when the domain is disabled: its ServerState is saved and cleared from
|
* memory, and it is loaded again from the backend when the domain is enabled back, so
|
* the bookkeeping which goes with it must not outlive it. A change which stayed here
|
* would be discarded as a duplicate when the replication server sends it again, and
|
* nothing would ever replay it or record it in the ServerState.
|
*/
|
public void clear()
|
{
|
pendingChangesWriteLock.lock();
|
dependentChangesLock.lock();
|
try
|
{
|
pendingChanges.clear();
|
dependentChanges.clear();
|
activeAndDependentChanges.clear();
|
changeBeingReplayed.clear();
|
failingChanges = 0;
|
}
|
finally
|
{
|
dependentChangesLock.unlock();
|
pendingChangesWriteLock.unlock();
|
}
|
}
|
|
/**
|
* Marks the change of the provided message as being replayed.
|
*
|
* @param msg
|
* the message whose change is being replayed
|
* @return {@code false} if this message is not the delivery which is listed as
|
* pending, which happens when the session was restarted after a failed replay
|
* while this message was still waiting in the replay queue: the replication
|
* server delivered the change again and that delivery took over from this one,
|
* or the domain was disabled and forgot the change, so this copy must not be
|
* replayed.
|
*/
|
public boolean markInProgress(LDAPUpdateMsg msg)
|
{
|
pendingChangesWriteLock.lock();
|
try
|
{
|
final PendingChange change = pendingChanges.get(msg.getCSN());
|
if (change == null || change.isCommitted() || change.getLDAPUpdateMsg() != msg)
|
{
|
return false;
|
}
|
/*
|
* Listed as being replayed before it is owned, and not the other way round: the
|
* caller enters the replay - where the give-back on the way out lives - once this
|
* returns, so nothing which allocates must run between the owner being stamped and
|
* that. A change listed here without an owner is the state a failed replay leaves
|
* behind, and the dependency checks which read this set do not read the owner.
|
*/
|
activeAndDependentChanges.add(change);
|
changeBeingReplayed.put(Thread.currentThread(), change.getCSN());
|
change.setOwner(Thread.currentThread());
|
return true;
|
}
|
finally
|
{
|
pendingChangesWriteLock.unlock();
|
}
|
}
|
/**
|
* Returns the CSN of the change the calling thread is replaying, when it still owns one.
|
* <p>
|
* A thread owns the change it is replaying and the ones it parked as waiting for another
|
* change. The parked ones are left out: they are handed to whichever thread clears the
|
* change they are waiting for, and that thread takes them over, so giving one back here
|
* would have the same change handed to two threads (issue #922).
|
* <p>
|
* It is a plain read of {@link #changeBeingReplayed}: no lock is taken and nothing is
|
* allocated. This is what the give-back on the way out of an unwound replay asks first,
|
* and it runs on a road an {@code OutOfMemoryError} leads to - a lookup which allocated
|
* could be refused in its turn, and a give-back which does not know which change to give
|
* back leaves it listed, uncommitted and owned by a thread which is not replaying it
|
* anymore, which is the wedge this issue is about.
|
* <p>
|
* An answer which is out of date is safe: every road which acts on it - {@code commit()},
|
* {@link #recordReplayFailure(CSN, long)} and {@link #replayFailed(CSN)} - checks the
|
* ownership of the change again under the write lock, and is a no-op for a change this
|
* thread does not own anymore.
|
*
|
* @return the CSN of the change this thread is replaying, or {@code null} when it does
|
* not own one anymore - the road its replay took gave it back, or it was applied
|
*/
|
CSN getChangeOwnedByCurrentThread()
|
{
|
return changeBeingReplayed.get(Thread.currentThread());
|
}
|
|
/**
|
* Get the first update in the list that have some dependencies cleared.
|
* <p>
|
* The change is handed to the calling thread, which owns it from then on: it is
|
* replayed by whichever replay thread cleared the change it was waiting for rather than
|
* by the one which parked it, and a change is given back by the thread which owns it
|
* and by nobody else (issue #922).
|
*
|
* @return The LDAPUpdateMsg to be handled.
|
*/
|
public LDAPUpdateMsg getNextUpdate()
|
{
|
pendingChangesReadLock.lock();
|
dependentChangesLock.lock();
|
try
|
{
|
if (!hasChangeToHandOut())
|
{
|
/*
|
* Nothing is waiting, or what waits is still held back by the changes before it.
|
* This is called at the end of every replay, by every replay thread, so the answer
|
* is looked for under the read lock: taking the write lock here would have a
|
* backlog of waiting changes serialize the replay of the changes which have none.
|
*/
|
return null;
|
}
|
}
|
finally
|
{
|
dependentChangesLock.unlock();
|
pendingChangesReadLock.unlock();
|
}
|
|
/*
|
* There is one to hand out, and handing it out writes its owner, which is written
|
* under the write lock as the rest of the state of a change is. It is looked for again
|
* under that lock: another replay thread may have been handed it in between.
|
*/
|
pendingChangesWriteLock.lock();
|
dependentChangesLock.lock();
|
try
|
{
|
if (hasChangeToHandOut())
|
{
|
final PendingChange firstDependentChange = dependentChanges.first();
|
/*
|
* Entered as the change this thread is replaying before it is taken out of the
|
* ones which are waiting, for the same reason markInProgress() enters it before it
|
* stamps the owner: an allocation which fails here must leave the change where it
|
* was rather than take it out of the hands which would hand it out again.
|
*/
|
changeBeingReplayed.put(Thread.currentThread(), firstDependentChange.getCSN());
|
dependentChanges.remove(firstDependentChange);
|
firstDependentChange.setOwner(Thread.currentThread());
|
return firstDependentChange.getLDAPUpdateMsg();
|
}
|
return null;
|
}
|
finally
|
{
|
dependentChangesLock.unlock();
|
pendingChangesWriteLock.unlock();
|
}
|
}
|
|
/**
|
* Returns whether the first change waiting for another one can be replayed now, that is
|
* whether every change before it has left the pending changes.
|
*/
|
@GuardedBy("pendingChangesLock, dependentChangesLock")
|
private boolean hasChangeToHandOut()
|
{
|
return !dependentChanges.isEmpty()
|
&& !pendingChanges.isEmpty()
|
&& pendingChanges.firstKey().isNewerThanOrEqualTo(dependentChanges.first().getCSN());
|
}
|
|
/**
|
* Mark the first pendingChange as dependent on the second PendingChange.
|
* @param dependentChange The PendingChange that depend on the second
|
* PendingChange.
|
*/
|
private void addDependency(PendingChange dependentChange)
|
{
|
pendingChangesReadLock.lock();
|
dependentChangesLock.lock();
|
try
|
{
|
/*
|
* A change which is not listed as pending anymore - the domain was disabled while
|
* its dependencies were computed - must not be listed as dependent either:
|
* getNextUpdate() reads both and would hand out a change nothing owns. The
|
* replication server sends it again when the domain is enabled back.
|
*/
|
if (pendingChanges.containsKey(dependentChange.getCSN()))
|
{
|
dependentChanges.add(dependentChange);
|
}
|
/*
|
* Whichever of the two it was, this thread is not replaying that change anymore: a
|
* parked one is handed to the thread which clears what it waits for, and one which is
|
* not listed here anymore is gone with the pending changes of a domain which was
|
* disabled. The owner stays as it is - it is what has getNextUpdate() hand the change
|
* over rather than leave it to nobody - and the give-back on the way out of an
|
* unwound replay leaves it alone (issue #922).
|
*/
|
changeBeingReplayed.remove(Thread.currentThread(), dependentChange.getCSN());
|
}
|
finally
|
{
|
dependentChangesLock.unlock();
|
pendingChangesReadLock.unlock();
|
}
|
}
|
|
private PendingChange getPendingChange(CSN csn)
|
{
|
pendingChangesReadLock.lock();
|
try
|
{
|
return pendingChanges.get(csn);
|
}
|
finally
|
{
|
pendingChangesReadLock.unlock();
|
}
|
}
|
|
/**
|
* Check if the given AddOperation has some dependencies on any
|
* currently running previous operation.
|
* Update the dependency list in the associated PendingChange if
|
* there are some dependencies.
|
* AddOperation depends on
|
*
|
* - DeleteOperation done on the same DN
|
* - ModifyDnOperation with the same target DN as the ADD DN
|
* - ModifyDnOperation with new DN equals to the ADD DN parent
|
* - AddOperation done on the parent DN of the ADD DN
|
*
|
* @param op The AddOperation to be checked.
|
*
|
* @return A boolean indicating if this operation has some dependencies.
|
*/
|
public boolean checkDependencies(AddOperation op)
|
{
|
final CSN csn = OperationContext.getCSN(op);
|
final PendingChange change = getPendingChange(csn);
|
if (change == null)
|
{
|
return false;
|
}
|
|
boolean hasDependencies = false;
|
final DN targetDN = op.getEntryDN();
|
for (PendingChange pendingChange : activeAndDependentChanges)
|
{
|
if (pendingChange.getCSN().isNewerThanOrEqualTo(csn))
|
{
|
// From now on, the dependency should be for newer changes to be dependent on this one, so we can stop for now.
|
break;
|
}
|
final LDAPUpdateMsg pendingMsg = pendingChange.getLDAPUpdateMsg();
|
if (pendingMsg instanceof DeleteMsg)
|
{
|
if (pendingMsg.getDN().equals(targetDN))
|
{
|
// it is a deleteOperation on the same DN
|
hasDependencies = true;
|
addDependency(change);
|
}
|
}
|
else if (pendingMsg instanceof AddMsg)
|
{
|
if (pendingMsg.getDN().isSuperiorOrEqualTo(targetDN))
|
{
|
// it is an addOperation on a parent of the current AddOperation
|
hasDependencies = true;
|
addDependency(change);
|
}
|
}
|
else if (pendingMsg instanceof ModifyDNMsg)
|
{
|
// it is a ModifyDnOperation with the same target DN as the ADD DN
|
// or a ModifyDnOperation with new DN equals to the ADD DN parent?
|
if (pendingMsg.getDN().equals(targetDN))
|
{
|
hasDependencies = true;
|
addDependency(change);
|
}
|
else
|
{
|
final ModifyDNMsg pendingModDn = (ModifyDNMsg) pendingMsg;
|
if (pendingModDn.newDNIsParent(targetDN))
|
{
|
hasDependencies = true;
|
addDependency(change);
|
}
|
}
|
}
|
}
|
return hasDependencies;
|
}
|
|
/**
|
* Check if the given ModifyOperation has some dependencies on any
|
* currently running previous operation.
|
* Update the dependency list in the associated PendingChange if
|
* there are some dependencies.
|
*
|
* ModifyOperation depends on
|
* - AddOperation done on the same DN
|
* - ModifyDNOperation having newDN the same as targetDN
|
*
|
* @param op The ModifyOperation to be checked.
|
*
|
* @return A boolean indicating if this operation has some dependencies.
|
*/
|
public boolean checkDependencies(ModifyOperation op)
|
{
|
final CSN csn = OperationContext.getCSN(op);
|
final PendingChange change = getPendingChange(csn);
|
if (change == null)
|
{
|
return false;
|
}
|
|
boolean hasDependencies = false;
|
final DN targetDN = change.getLDAPUpdateMsg().getDN();
|
for (PendingChange pendingChange : activeAndDependentChanges)
|
{
|
if (pendingChange.getCSN().isNewerThanOrEqualTo(csn))
|
{
|
// From now on, the dependency should be for newer changes to be dependent on this one, so we can stop for now.
|
break;
|
}
|
final LDAPUpdateMsg pendingMsg = pendingChange.getLDAPUpdateMsg();
|
if (pendingMsg instanceof AddMsg)
|
{
|
if (pendingMsg.getDN().equals(targetDN))
|
{
|
// it is an addOperation on a same DN
|
hasDependencies = true;
|
addDependency(change);
|
}
|
}
|
else if (pendingMsg instanceof ModifyDNMsg)
|
{
|
if (((ModifyDNMsg) pendingMsg).newDNIsEqual(targetDN))
|
{
|
hasDependencies = true;
|
addDependency(change);
|
}
|
}
|
else if (pendingMsg instanceof ModifyMsg)
|
{
|
if (pendingMsg.getDN().equals(targetDN))
|
{
|
// it is another modify on the same DN, they depend
|
hasDependencies = true;
|
addDependency(change);
|
}
|
}
|
}
|
return hasDependencies;
|
}
|
|
/**
|
* Check if the given ModifyDNMsg has some dependencies on any
|
* currently running previous operation.
|
* Update the dependency list in the associated PendingChange if
|
* there are some dependencies.
|
*
|
* Modify DN Operation depends on
|
* - AddOperation done on the same DN as the target DN of the MODDN operation
|
* - AddOperation done on the new parent of the MODDN operation
|
* - DeleteOperation done on the new DN of the MODDN operation
|
* - ModifyDNOperation done from the new DN of the MODDN operation
|
*
|
* TODO: Consider cases where there is a rename A -> B then rename B -> C. Second change depends on first
|
*
|
* @param msg The ModifyDNMsg to be checked.
|
*
|
* @return A boolean indicating if this operation has some dependencies.
|
*/
|
public boolean checkDependencies(ModifyDNMsg msg)
|
{
|
final CSN csn = msg.getCSN();
|
final PendingChange change = getPendingChange(csn);
|
if (change == null)
|
{
|
return false;
|
}
|
|
boolean hasDependencies = false;
|
final DN targetDN = change.getLDAPUpdateMsg().getDN();
|
for (PendingChange pendingChange : activeAndDependentChanges)
|
{
|
if (pendingChange.getCSN().isNewerThanOrEqualTo(csn))
|
{
|
// From now on, the dependency should be for newer changes to be dependent on this one, so we can stop for now.
|
break;
|
}
|
final LDAPUpdateMsg pendingMsg = pendingChange.getLDAPUpdateMsg();
|
if (pendingMsg instanceof DeleteMsg)
|
{
|
// Check if the target of the Delete is the same
|
// as the new DN of this ModifyDN
|
if (msg.newDNIsEqual(pendingMsg.getDN()))
|
{
|
hasDependencies = true;
|
addDependency(change);
|
}
|
}
|
else if (pendingMsg instanceof AddMsg)
|
{
|
// Check if the Add Operation was done on the new parent of
|
// the MODDN operation
|
if (msg.newParentIsEqual(pendingMsg.getDN()))
|
{
|
hasDependencies = true;
|
addDependency(change);
|
}
|
// Check if the AddOperation was done on the same DN as the
|
// target DN of the MODDN operation
|
if (pendingMsg.getDN().equals(targetDN))
|
{
|
hasDependencies = true;
|
addDependency(change);
|
}
|
}
|
else if (pendingMsg instanceof ModifyDNMsg)
|
{
|
if (msg.newDNIsEqual(pendingMsg.getDN()))
|
{
|
// the ModifyDNOperation was done from the new DN of the MODDN operation
|
hasDependencies = true;
|
addDependency(change);
|
}
|
}
|
}
|
return hasDependencies;
|
}
|
|
/**
|
* Check if the given DeleteOperation has some dependencies on any
|
* currently running previous operation.
|
* Update the dependency list in the associated PendingChange if
|
* there are some dependencies.
|
*
|
* DeleteOperation depends on
|
* - DeleteOperation done on children DN
|
* - ModifyDnOperation with target DN that are children of the DEL DN
|
* - AddOperation done on the same DN
|
*
|
*
|
* @param op The DeleteOperation to be checked.
|
*
|
* @return A boolean indicating if this operation has some dependencies.
|
*/
|
public boolean checkDependencies(DeleteOperation op)
|
{
|
final CSN csn = OperationContext.getCSN(op);
|
final PendingChange change = getPendingChange(csn);
|
if (change == null)
|
{
|
return false;
|
}
|
|
boolean hasDependencies = false;
|
final DN targetDN = op.getEntryDN();
|
for (PendingChange pendingChange : activeAndDependentChanges)
|
{
|
if (pendingChange.getCSN().isNewerThanOrEqualTo(csn))
|
{
|
// From now on, the dependency should be for newer changes to be dependent on this one, so we can stop for now.
|
break;
|
}
|
final LDAPUpdateMsg pendingMsg = pendingChange.getLDAPUpdateMsg();
|
if (pendingMsg instanceof DeleteMsg)
|
{
|
/*
|
* Check if the operation to be run is a deleteOperation on a
|
* children of the current DeleteOperation.
|
*/
|
if (pendingMsg.getDN().isSubordinateOrEqualTo(targetDN))
|
{
|
hasDependencies = true;
|
addDependency(change);
|
}
|
}
|
else if (pendingMsg instanceof AddMsg)
|
{
|
/*
|
* Check if the operation to be run is an addOperation on a
|
* parent of the current DeleteOperation.
|
*/
|
if (pendingMsg.getDN().equals(targetDN))
|
{
|
hasDependencies = true;
|
addDependency(change);
|
}
|
}
|
else if (pendingMsg instanceof ModifyDNMsg)
|
{
|
final ModifyDNMsg pendingModDn = (ModifyDNMsg) pendingMsg;
|
/*
|
* Check if the operation to be run is an ModifyDNOperation
|
* on a children of the current DeleteOperation
|
*/
|
if (pendingMsg.getDN().isSubordinateOrEqualTo(targetDN) || pendingModDn.newDNIsParent(targetDN))
|
{
|
hasDependencies = true;
|
addDependency(change);
|
}
|
}
|
}
|
return hasDependencies;
|
}
|
|
/**
|
* Check the dependencies of a given Operation/UpdateMsg.
|
*
|
* @param op The Operation for which dependencies must be checked.
|
* @param msg The LocalizableMessage for which dependencies must be checked.
|
* @return A boolean indicating if an operation cannot be replayed
|
* because of dependencies.
|
*/
|
public boolean checkDependencies(Operation op, LDAPUpdateMsg msg)
|
{
|
if (op instanceof ModifyOperation)
|
{
|
return checkDependencies((ModifyOperation) op);
|
}
|
else if (op instanceof DeleteOperation)
|
{
|
return checkDependencies((DeleteOperation) op);
|
}
|
else if (op instanceof AddOperation)
|
{
|
return checkDependencies((AddOperation) op);
|
}
|
else if (op instanceof ModifyDNOperationBasis)
|
{
|
return checkDependencies((ModifyDNMsg) msg);
|
}
|
else
|
{
|
return true; // unknown type of operation ?!
|
}
|
}
|
}
|
