/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at legal-notices/CDDLv1_0.txt
* or http://forgerock.org/license/CDDLv1.0.html.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at legal-notices/CDDLv1_0.txt.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information:
* Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*
*
* Copyright 2006-2010 Sun Microsystems, Inc.
* Portions Copyright 2011-2015 ForgeRock AS
*/
package org.opends.server.replication.server;
import java.net.SocketException;
import org.forgerock.i18n.LocalizableMessage;
import org.opends.server.api.DirectoryThread;
import org.forgerock.i18n.slf4j.LocalizedLogger;
import org.opends.server.replication.common.ServerStatus;
import org.opends.server.replication.protocol.*;
import static org.opends.messages.ReplicationMessages.*;
import static org.opends.server.replication.common.ServerStatus.*;
import static org.opends.server.util.StaticUtils.*;
/**
* This class implement the part of the replicationServer that is reading
* the connection from the LDAP servers to get all the updates that
* were done on this replica and forward them to other servers.
*
* A single thread is dedicated to this work.
* It waits in a blocking mode on the connection from the LDAP server
* and upon receiving an update puts in into the replicationServer cache
* from where the other servers will grab it.
*/
public class ServerReader extends DirectoryThread
{
private static final LocalizedLogger logger = LocalizedLogger.getLoggerForThisClass();
private final Session session;
private final ServerHandler handler;
/**
* Constructor for the LDAP server reader part of the replicationServer.
*
* @param session
* The Session from which to read the data.
* @param handler
* The server handler for this server reader.
*/
public ServerReader(Session session, ServerHandler handler)
{
super("Replication server RS(" + handler.getReplicationServerId()
+ ") reading from " + handler + " at "
+ session.getReadableRemoteAddress());
this.session = session;
this.handler = handler;
}
/**
* Create a loop that reads changes and hands them off to be processed.
*/
@Override
public void run()
{
if (logger.isTraceEnabled())
{
logger.trace(getName() + " starting");
}
/*
* wait on input stream
* grab all incoming messages and publish them to the
* replicationServerDomain
*/
LocalizableMessage errMessage = null;
try
{
while (true)
{
try
{
final ReplicationMsg msg = session.receive();
if (logger.isTraceEnabled())
{
logger.trace("In " + getName() + " receives " + msg);
}
if (msg instanceof AckMsg)
{
handler.checkWindow();
handler.processAck((AckMsg) msg);
}
else if (msg instanceof UpdateMsg)
{
final UpdateMsg updateMsg = (UpdateMsg) msg;
if (!isUpdateMsgFiltered(updateMsg))
{
handler.put(updateMsg);
}
}
else if (msg instanceof WindowMsg)
{
handler.updateWindow((WindowMsg) msg);
}
else if (msg instanceof MonitorRequestMsg)
{
handler.processMonitorRequestMsg((MonitorRequestMsg) msg);
}
else if (msg instanceof MonitorMsg)
{
handler.processMonitorMsg((MonitorMsg) msg);
}
else if (msg instanceof RoutableMsg)
{
/*
* Note that we handle monitor messages separately since they in
* fact never need "routing" and are instead sent directly between
* connected peers. Doing so allows us to more clearly decouple
* write IO from the reader thread (see OPENDJ-1354).
*/
handler.process((RoutableMsg) msg);
}
else if (msg instanceof ResetGenerationIdMsg)
{
handler.processResetGenId((ResetGenerationIdMsg) msg);
}
else if (msg instanceof WindowProbeMsg)
{
handler.replyToWindowProbe();
}
else if (msg instanceof TopologyMsg)
{
ReplicationServerHandler rsh = (ReplicationServerHandler) handler;
rsh.receiveTopoInfoFromRS((TopologyMsg) msg);
}
else if (msg instanceof ChangeStatusMsg)
{
ChangeStatusMsg csMsg = (ChangeStatusMsg) msg;
try
{
DataServerHandler dsh = (DataServerHandler) handler;
dsh.receiveNewStatus(csMsg);
}
catch (Exception e)
{
errMessage = ERR_RECEIVED_CHANGE_STATUS_NOT_FROM_DS.get(
handler.getBaseDN(), handler.getServerId(), csMsg);
logger.error(errMessage);
}
}
else if (msg instanceof ChangeTimeHeartbeatMsg)
{
handler.process((ChangeTimeHeartbeatMsg) msg);
}
else if (msg instanceof StopMsg)
{
/*
* Peer server is properly disconnecting: go out of here to properly
* close the server handler going to finally block.
*/
if (logger.isTraceEnabled())
{
logger.trace(handler
+ " has properly disconnected from this replication server "
+ handler.getReplicationServerId());
}
return;
}
else if (msg == null)
{
/*
* The remote server has sent an unknown message, close the
* connection.
*/
errMessage = NOTE_READER_NULL_MSG.get(handler);
logger.info(errMessage);
return;
}
}
catch (NotSupportedOldVersionPDUException e)
{
/*
* Received a V1 PDU we do not need to support: we just trash the
* message and log the event for debug purpose, then continue
* receiving messages.
*/
logException(e);
}
}
}
catch (SocketException e)
{
/*
* The connection has been broken Log a message and exit from this loop So
* that this handler is stopped.
*/
logException(e);
if (!handler.shuttingDown())
{
errMessage = handler.getBadlyDisconnectedErrorMessage();
logger.error(errMessage);
}
}
catch (Exception e)
{
/*
* The remote server has sent an unknown message, close the connection.
*/
errMessage = NOTE_READER_EXCEPTION.get(handler,
stackTraceToSingleLineString(e));
logger.info(errMessage);
}
finally
{
/*
* The thread only exits the loop above if some error condition happen.
* Attempt to close the socket and stop the server handler.
*/
if (logger.isTraceEnabled())
{
logger.trace("In " + getName() + " closing the session");
}
session.close();
handler.doStop();
if (logger.isTraceEnabled())
{
logger.trace(getName() + " stopped: " + errMessage);
}
}
}
/**
* Returns whether the update message is filtered in one of those cases:
* <ul>
* <li>Ignore updates from DS in bad BAD_GENID_STATUS or FULL_UPDATE_STATUS</li>
* <li>Ignore updates from RS with bad gen id</li>
* </ul>
*/
private boolean isUpdateMsgFiltered(UpdateMsg updateMsg)
{
if (handler.isDataServer())
{
/**
* Ignore updates from DS in bad BAD_GENID_STATUS or
* FULL_UPDATE_STATUS
*
* The RSD lock should not be taken here as it is acceptable to
* have a delay between the time the server has a wrong status and
* the fact we detect it: the updates that succeed to pass during
* this time will have no impact on remote server. But it is
* interesting to not saturate uselessly the network if the
* updates are not necessary so this check to stop sending updates
* is interesting anyway. Not taking the RSD lock allows to have
* better performances in normal mode (most of the time).
*/
final ServerStatus dsStatus = handler.getStatus();
if (dsStatus == BAD_GEN_ID_STATUS)
{
logger.warn(WARN_IGNORING_UPDATE_FROM_DS_BADGENID,
handler.getReplicationServerId(), updateMsg.getCSN(),
handler.getBaseDN(), handler.getServerId(),
session.getReadableRemoteAddress(),
handler.getGenerationId(), handler.getReferenceGenId());
return true;
}
else if (dsStatus == FULL_UPDATE_STATUS)
{
logger.warn(WARN_IGNORING_UPDATE_FROM_DS_FULLUP,
handler.getReplicationServerId(), updateMsg.getCSN(),
handler.getBaseDN(), handler.getServerId(),
session.getReadableRemoteAddress());
return true;
}
}
else
{
/**
* Ignore updates from RS with bad gen id
* (no system managed status for a RS)
*/
long referenceGenerationId = handler.getReferenceGenId();
if (referenceGenerationId > 0
&& referenceGenerationId != handler.getGenerationId())
{
logger.error(WARN_IGNORING_UPDATE_FROM_RS,
handler.getReplicationServerId(), updateMsg.getCSN(),
handler.getBaseDN(), handler.getServerId(),
session.getReadableRemoteAddress(),
handler.getGenerationId(), referenceGenerationId);
return true;
}
}
return false;
}
private void logException(Exception e)
{
if (logger.isTraceEnabled())
{
logger.trace("In " + getName() + " " + stackTraceToSingleLineString(e));
}
}
}