/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.jackrabbit.core.cluster;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.atomic.AtomicInteger;
import javax.jcr.RepositoryException;
import org.apache.jackrabbit.core.cluster.WorkspaceRecord.CreateWorkspaceAction;
import org.apache.jackrabbit.core.config.ClusterConfig;
import org.apache.jackrabbit.core.id.NodeId;
import org.apache.jackrabbit.core.journal.AbstractJournal;
import org.apache.jackrabbit.core.journal.InstanceRevision;
import org.apache.jackrabbit.core.journal.Journal;
import org.apache.jackrabbit.core.journal.JournalException;
import org.apache.jackrabbit.core.journal.Record;
import org.apache.jackrabbit.core.journal.RecordConsumer;
import org.apache.jackrabbit.core.journal.RecordProducer;
import org.apache.jackrabbit.core.nodetype.InvalidNodeTypeDefException;
import org.apache.jackrabbit.core.observation.EventState;
import org.apache.jackrabbit.core.state.ChangeLog;
import org.apache.jackrabbit.core.version.InternalVersionManagerImpl;
import org.apache.jackrabbit.core.xml.ClonedInputSource;
import org.apache.jackrabbit.spi.QNodeTypeDefinition;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import EDU.oswego.cs.dl.util.concurrent.Latch;
import EDU.oswego.cs.dl.util.concurrent.Mutex;
/**
* Default clustered node implementation.
*/
public class ClusterNode implements Runnable,
NamespaceEventChannel, NodeTypeEventChannel, RecordConsumer,
ClusterRecordProcessor, WorkspaceEventChannel {
/**
* System property specifying a node id to use.
*/
public static final String SYSTEM_PROPERTY_NODE_ID = "org.apache.jackrabbit.core.cluster.node_id";
/**
* Producer identifier.
*/
private static final String PRODUCER_ID = "JR";
/**
* Status constant.
*/
private static final int NONE = 0;
/**
* Status constant.
*/
private static final int STARTED = 1;
/**
* Status constant.
*/
private static final int STOPPED = 2;
/**
* Logger.
*/
private static Logger log = LoggerFactory.getLogger(ClusterNode.class);
/**
* Cluster context.
*/
private ClusterContext clusterContext;
/**
* Cluster node id.
*/
private String clusterNodeId;
/**
* Synchronization delay, in milliseconds.
*/
private long syncDelay;
/**
* Stop delay, in milliseconds.
*/
private long stopDelay;
/**
* Journal used.
*/
private Journal journal;
/**
* Synchronization thread.
*/
private Thread syncThread;
/**
* Mutex used when syncing.
*/
private final Mutex syncLock = new Mutex();
/**
* Latch used to communicate a stop request to the synchronization thread.
*/
private final Latch stopLatch = new Latch();
/**
* Sync counter, used to avoid repeated sync() calls from piling up.
* Only updated within the critical section guarded by {@link #syncLock}.
*
* @since Apache Jackrabbit 1.6
* @see <a href="https://issues.apache.org/jira/browse/JCR-1753">JCR-1753</a>
*/
private AtomicInteger syncCount = new AtomicInteger();
/**
* Status flag, one of {@link #NONE}, {@link #STARTED} or {@link #STOPPED}.
*/
private int status;
/**
* Map of available lock listeners, indexed by workspace name.
*/
private final Map<String, LockEventListener> wspLockListeners = new HashMap<String, LockEventListener>();
/**
* Map of available update listeners, indexed by workspace name.
*/
private final Map<String, UpdateEventListener> wspUpdateListeners = new HashMap<String, UpdateEventListener>();
/**
* Versioning update listener.
*/
private UpdateEventListener versionUpdateListener;
/**
* Namespace listener.
*/
private NamespaceEventListener namespaceListener;
/**
* Create workspace listener
*/
private WorkspaceListener createWorkspaceListener;
/**
* Node type listener.
*/
private NodeTypeEventListener nodeTypeListener;
/**
* Instance revision manager.
*/
private InstanceRevision instanceRevision;
/**
* Our record producer.
*/
private RecordProducer producer;
/**
* Record deserializer.
*/
private ClusterRecordDeserializer deserializer = new ClusterRecordDeserializer();
/**
* Initialize this cluster node.
*
* @throws ClusterException if an error occurs
*/
public void init(ClusterContext clusterContext) throws ClusterException {
this.clusterContext = clusterContext;
init();
}
/**
* Initialize this cluster node (overridable).
*
* @throws ClusterException if an error occurs
*/
protected void init() throws ClusterException {
ClusterConfig cc = clusterContext.getClusterConfig();
clusterNodeId = cc.getId();
syncDelay = cc.getSyncDelay();
try {
journal = cc.getJournal(clusterContext.getNamespaceResolver());
instanceRevision = journal.getInstanceRevision();
journal.register(this);
producer = journal.getProducer(PRODUCER_ID);
} catch (RepositoryException e) {
throw new ClusterException(
"Cluster initialization failed: " + this, e);
} catch (JournalException e) {
throw new ClusterException(
"Journal initialization failed: " + this, e);
}
}
/**
* Set the stop delay, i.e. number of millseconds to wait for the
* synchronization thread to stop.
*
* @param stopDelay stop delay in milliseconds
*/
public void setStopDelay(long stopDelay) {
this.stopDelay = stopDelay;
}
/**
* Return the stop delay.
*
* @return stop delay
* @see #setStopDelay(long)
*/
public long getStopDelay() {
return stopDelay;
}
/**
* Starts this cluster node.
*
* @throws ClusterException if an error occurs
*/
public synchronized void start() throws ClusterException {
if (status == NONE) {
sync();
Thread t = new Thread(this, "ClusterNode-" + clusterNodeId);
t.setDaemon(true);
t.start();
syncThread = t;
status = STARTED;
}
}
/**
* Run loop that will sync this node after some delay.
*/
public void run() {
for (;;) {
try {
if (stopLatch.attempt(syncDelay)) {
break;
}
} catch (InterruptedException e) {
String msg = "Interrupted while waiting for stop latch.";
log.warn(msg);
}
try {
sync();
} catch (ClusterException e) {
String msg = "Periodic sync of journal failed: " + e.getMessage();
log.error(msg, e);
} catch (Exception e) {
String msg = "Unexpected error while syncing of journal: " + e.getMessage();
log.error(msg, e);
} catch (Error e) {
String msg = "Unexpected error while syncing of journal: " + e.getMessage();
log.error(msg, e);
throw e;
}
}
}
/**
* Synchronize contents from journal.
*
* @throws ClusterException if an error occurs
*/
public void sync() throws ClusterException {
int count = syncCount.get();
try {
syncLock.acquire();
} catch (InterruptedException e) {
String msg = "Interrupted while waiting for mutex.";
throw new ClusterException(msg);
}
try {
// JCR-1753: Only synchronize if no other thread already did so
// while we were waiting to acquire the syncLock.
if (count == syncCount.get()) {
syncCount.incrementAndGet();
journal.sync();
}
} catch (JournalException e) {
throw new ClusterException(e.getMessage(), e.getCause());
} finally {
syncLock.release();
}
}
/**
* Stops this cluster node.
*/
public synchronized void stop() {
if (status != STOPPED) {
status = STOPPED;
stopLatch.release();
// Give synchronization thread some time to finish properly before
// closing down the journal (see JCR-1553)
if (syncThread != null) {
try {
syncThread.join(stopDelay);
} catch (InterruptedException e) {
String msg = "Interrupted while joining synchronization thread.";
log.warn(msg);
}
}
if (journal != null) {
journal.close();
}
if (instanceRevision != null) {
instanceRevision.close();
}
}
}
/**
* Create an {@link UpdateEventChannel} for some workspace.
*
* @param workspace workspace name
* @return lock event channel
*/
public UpdateEventChannel createUpdateChannel(String workspace) {
return new WorkspaceUpdateChannel(workspace);
}
/**
* Create a {@link LockEventChannel} for some workspace.
*
* @param workspace workspace name
* @return lock event channel
*/
public LockEventChannel createLockChannel(String workspace) {
return new WorkspaceLockChannel(workspace);
}
/**
* Return the journal created by this cluster node.
*
* @return journal
*/
public Journal getJournal() {
return journal;
}
//-----------------------------------------------< NamespaceEventListener >
/**
* {@inheritDoc}
*/
public void remapped(String oldPrefix, String newPrefix, String uri) {
if (status != STARTED) {
log.info("not started: namespace operation ignored.");
return;
}
ClusterRecord record = null;
boolean succeeded = false;
try {
record = new NamespaceRecord(oldPrefix, newPrefix, uri, producer.append());
record.write();
record.update();
setRevision(record.getRevision());
succeeded = true;
} catch (JournalException e) {
String msg = "Unable to create log entry: " + e.getMessage();
log.error(msg);
} catch (Throwable e) {
String msg = "Unexpected error while creating log entry.";
log.error(msg, e);
} finally {
if (!succeeded && record != null) {
record.cancelUpdate();
}
}
}
public void setListener(NamespaceEventListener listener) {
namespaceListener = listener;
}
//------------------------------------------------< NodeTypeEventListener >
/**
* {@inheritDoc}
*/
public void registered(Collection ntDefs) {
if (status != STARTED) {
log.info("not started: nodetype operation ignored.");
return;
}
ClusterRecord record = null;
boolean succeeded = false;
try {
record = new NodeTypeRecord(ntDefs, true, producer.append());
record.write();
record.update();
setRevision(record.getRevision());
succeeded = true;
} catch (JournalException e) {
String msg = "Unable to create log entry: " + e.getMessage();
log.error(msg);
} catch (Throwable e) {
String msg = "Unexpected error while creating log entry.";
log.error(msg, e);
} finally {
if (!succeeded && record != null) {
record.cancelUpdate();
}
}
}
/**
* {@inheritDoc}
*/
public void reregistered(QNodeTypeDefinition ntDef) {
if (status != STARTED) {
log.info("not started: nodetype operation ignored.");
return;
}
ClusterRecord record = null;
boolean succeeded = false;
try {
record = new NodeTypeRecord(ntDef, producer.append());
record.write();
record.update();
setRevision(record.getRevision());
succeeded = true;
} catch (JournalException e) {
String msg = "Unable to create log entry: " + e.getMessage();
log.error(msg);
} catch (Throwable e) {
String msg = "Unexpected error while creating log entry.";
log.error(msg, e);
} finally {
if (!succeeded && record != null) {
record.cancelUpdate();
}
}
}
/**
* {@inheritDoc}
*/
public void unregistered(Collection qnames) {
if (status != STARTED) {
log.info("not started: nodetype operation ignored.");
return;
}
ClusterRecord record = null;
boolean succeeded = false;
try {
record = new NodeTypeRecord(qnames, false, producer.append());
record.write();
record.update();
setRevision(record.getRevision());
succeeded = true;
} catch (JournalException e) {
String msg = "Unable to create log entry: " + e.getMessage();
log.error(msg);
} catch (Throwable e) {
String msg = "Unexpected error while creating log entry.";
log.error(msg, e);
} finally {
if (!succeeded && record != null) {
record.cancelUpdate();
}
}
}
/**
* {@inheritDoc}
*/
public void setListener(NodeTypeEventListener listener) {
nodeTypeListener = listener;
}
/**
* Workspace update channel.
*/
class WorkspaceUpdateChannel implements UpdateEventChannel {
/**
* Attribute name used to store record.
*/
private static final String ATTRIBUTE_RECORD = "record";
/**
* Workspace name.
*/
private final String workspace;
/**
* Create a new instance of this class.
*
* @param workspace workspace name
*/
public WorkspaceUpdateChannel(String workspace) {
this.workspace = workspace;
}
/**
* {@inheritDoc}
*/
public void updateCreated(Update update) {
if (status != STARTED) {
log.info("not started: update create ignored.");
return;
}
try {
Record record = producer.append();
update.setAttribute(ATTRIBUTE_RECORD, record);
} catch (JournalException e) {
String msg = "Unable to create log entry.";
log.error(msg, e);
} catch (Throwable e) {
String msg = "Unexpected error while creating log entry.";
log.error(msg, e);
}
}
/**
* {@inheritDoc}
*/
public void updatePrepared(Update update) {
if (status != STARTED) {
log.info("not started: update prepare ignored.");
return;
}
Record record = (Record) update.getAttribute(ATTRIBUTE_RECORD);
if (record == null) {
String msg = "No record created.";
log.warn(msg);
return;
}
List<EventState> events = update.getEvents();
ChangeLog changes = update.getChanges();
boolean succeeded = false;
try {
ChangeLogRecord clr = new ChangeLogRecord(changes, events,
record, workspace, update.getTimestamp(),
update.getUserData());
clr.write();
succeeded = true;
} catch (JournalException e) {
String msg = "Unable to create log entry: " + e.getMessage();
log.error(msg);
} catch (Throwable e) {
String msg = "Unexpected error while preparing log entry.";
log.error(msg, e);
} finally {
if (!succeeded && record != null) {
record.cancelUpdate();
update.setAttribute(ATTRIBUTE_RECORD, null);
}
}
}
/**
* {@inheritDoc}
*/
public void updateCommitted(Update update, String path) {
if (status != STARTED) {
log.info("not started: update commit ignored.");
return;
}
Record record = (Record) update.getAttribute(ATTRIBUTE_RECORD);
if (record == null) {
String msg = "No record prepared.";
log.warn(msg);
return;
}
try {
record.update();
setRevision(record.getRevision());
log.debug("revision {} {}", new Long(record.getRevision()), path);
} catch (JournalException e) {
String msg = "Unable to commit log entry.";
log.error(msg, e);
} catch (Throwable e) {
String msg = "Unexpected error while committing log entry.";
log.error(msg, e);
} finally {
update.setAttribute(ATTRIBUTE_RECORD, null);
}
}
/**
* {@inheritDoc}
*/
public void updateCancelled(Update update) {
if (status != STARTED) {
log.info("not started: update cancel ignored.");
return;
}
Record record = (Record) update.getAttribute(ATTRIBUTE_RECORD);
if (record != null) {
record.cancelUpdate();
update.setAttribute(ATTRIBUTE_RECORD, null);
}
}
/**
* {@inheritDoc}
*/
public void setListener(UpdateEventListener listener) {
if (workspace == null) {
versionUpdateListener = listener;
if (journal instanceof AbstractJournal &&
versionUpdateListener instanceof InternalVersionManagerImpl) {
((AbstractJournal) journal).setInternalVersionManager(
(InternalVersionManagerImpl) versionUpdateListener);
}
} else {
wspUpdateListeners.remove(workspace);
if (listener != null) {
wspUpdateListeners.put(workspace, listener);
}
}
}
}
/**
* Workspace lock channel.
*/
class WorkspaceLockChannel implements LockEventChannel {
/**
* Workspace name.
*/
private final String workspace;
/**
* Create a new instance of this class.
*
* @param workspace workspace name
*/
public WorkspaceLockChannel(String workspace) {
this.workspace = workspace;
}
/**
* {@inheritDoc}
*/
public ClusterOperation create(NodeId nodeId, boolean deep, String owner) {
if (status != STARTED) {
log.info("not started: lock operation ignored.");
return null;
}
try {
ClusterRecord record = new LockRecord(nodeId, deep, owner,
producer.append(), workspace);
return new DefaultClusterOperation(ClusterNode.this, record);
} catch (JournalException e) {
String msg = "Unable to create log entry: " + e.getMessage();
log.error(msg);
return null;
} catch (Throwable e) {
String msg = "Unexpected error while creating log entry.";
log.error(msg, e);
return null;
}
}
/**
* {@inheritDoc}
*/
public ClusterOperation create(NodeId nodeId) {
if (status != STARTED) {
log.info("not started: unlock operation ignored.");
return null;
}
try {
ClusterRecord record = new LockRecord(nodeId, producer.append(),
workspace);
return new DefaultClusterOperation(ClusterNode.this, record);
} catch (JournalException e) {
String msg = "Unable to create log entry: " + e.getMessage();
log.error(msg);
return null;
} catch (Throwable e) {
String msg = "Unexpected error while creating log entry.";
log.error(msg, e);
return null;
}
}
/**
* {@inheritDoc}
*/
public void setListener(LockEventListener listener) {
wspLockListeners.remove(workspace);
if (listener != null) {
wspLockListeners.put(workspace, listener);
}
}
}
//-------------------------------------------------------< RecordConsumer >
/**
* {@inheritDoc}
*/
public String getId() {
return PRODUCER_ID;
}
/**
* {@inheritDoc}
*/
public long getRevision() {
try {
return instanceRevision.get();
} catch (JournalException e) {
log.warn("Unable to return current revision.", e);
return Long.MAX_VALUE;
}
}
/**
* {@inheritDoc}
*/
public void consume(Record record) {
log.info("Processing revision: " + record.getRevision());
try {
deserializer.deserialize(record).process(this);
} catch (JournalException e) {
String msg = "Unable to read revision '" + record.getRevision() + "'.";
log.error(msg, e);
}
}
/**
* {@inheritDoc}
*/
public void setRevision(long revision) {
try {
instanceRevision.set(revision);
} catch (JournalException e) {
log.warn("Unable to set current revision to " + revision + ".", e);
}
}
//--------------------------------------------------- ClusterRecordProcessor
/**
* {@inheritDoc}
*/
public void process(ChangeLogRecord record) {
String workspace = record.getWorkspace();
UpdateEventListener listener = null;
if (workspace != null) {
listener = wspUpdateListeners.get(workspace);
if (listener == null) {
try {
clusterContext.updateEventsReady(workspace);
} catch (RepositoryException e) {
String msg = "Error making update listener for workspace " +
workspace + " online: " + e.getMessage();
log.warn(msg);
}
listener = wspUpdateListeners.get(workspace);
if (listener == null) {
String msg = "Update listener unavailable for workspace: " + workspace;
log.error(msg);
return;
}
}
} else {
if (versionUpdateListener != null) {
listener = versionUpdateListener;
} else {
String msg = "Version update listener unavailable.";
log.error(msg);
return;
}
}
try {
listener.externalUpdate(record.getChanges(), record.getEvents(),
record.getTimestamp(), record.getUserData());
} catch (RepositoryException e) {
String msg = "Unable to deliver update events: " + e.getMessage();
log.error(msg);
if (e.getCause() instanceof IllegalStateException) {
throw (IllegalStateException) e.getCause();
}
}
}
/**
* {@inheritDoc}
*/
public void process(LockRecord record) {
String workspace = record.getWorkspace();
LockEventListener listener = wspLockListeners.get(workspace);
if (listener == null) {
try {
clusterContext.lockEventsReady(workspace);
} catch (RepositoryException e) {
String msg = "Unable to make lock listener for workspace " +
workspace + " online: " + e.getMessage();
log.warn(msg);
}
listener = wspLockListeners.get(workspace);
if (listener == null) {
String msg = "Lock channel unavailable for workspace: " + workspace;
log.error(msg);
return;
}
}
try {
if (record.isLock()) {
listener.externalLock(record.getNodeId(), record.isDeep(),
record.getOwner());
} else {
listener.externalUnlock(record.getNodeId());
}
} catch (RepositoryException e) {
String msg = "Unable to deliver lock event: " + e.getMessage();
log.error(msg);
if (e.getCause() instanceof IllegalStateException) {
throw (IllegalStateException) e.getCause();
}
}
}
/**
* {@inheritDoc}
*/
public void process(NamespaceRecord record) {
if (namespaceListener == null) {
String msg = "Namespace listener unavailable.";
log.error(msg);
return;
}
try {
namespaceListener.externalRemap(record.getOldPrefix(),
record.getNewPrefix(), record.getUri());
} catch (RepositoryException e) {
String msg = "Unable to deliver namespace operation: " + e.getMessage();
log.error(msg);
}
}
/**
* {@inheritDoc}
*/
public void process(NodeTypeRecord record) {
if (nodeTypeListener == null) {
String msg = "NodeType listener unavailable.";
log.error(msg);
return;
}
Collection coll = record.getCollection();
try {
switch (record.getOperation()) {
case NodeTypeRecord.REGISTER:
nodeTypeListener.externalRegistered(coll);
break;
case NodeTypeRecord.UNREGISTER:
nodeTypeListener.externalUnregistered(coll);
break;
case NodeTypeRecord.REREGISTER:
QNodeTypeDefinition ntd = (QNodeTypeDefinition) coll.iterator().next();
nodeTypeListener.externalReregistered(ntd);
break;
}
} catch (InvalidNodeTypeDefException e) {
String msg = "Unable to deliver node type operation: " + e.getMessage();
log.error(msg);
} catch (RepositoryException e) {
String msg = "Unable to deliver node type operation: " + e.getMessage();
log.error(msg);
}
}
public void process(WorkspaceRecord record) {
if (createWorkspaceListener == null) {
String msg = "Create Workspace listener unavailable.";
log.error(msg);
return;
}
try {
if (record.getActionType() == WorkspaceRecord.CREATE_WORKSPACE_ACTION_TYPE) {
CreateWorkspaceAction action = record.getCreateWorkspaceAction();
createWorkspaceListener.externalWorkspaceCreated(record.getWorkspace(), action.getInputSource());
}
} catch (RepositoryException e) {
String msg = "Unable to create workspace: "
+ e.getMessage();
log.error(msg);
}
}
// -----------------------------------------------< CreateWorkspaceChannel >
public void setListener(WorkspaceListener listener) {
createWorkspaceListener = listener;
}
public void workspaceCreated(String workspaceName,
ClonedInputSource inputSource) {
if (status != STARTED) {
log.info("not started: namespace operation ignored.");
return;
}
ClusterRecord record = null;
boolean succeeded = false;
try {
record = new WorkspaceRecord(workspaceName, inputSource, producer.append());
record.write();
record.update();
setRevision(record.getRevision());
succeeded = true;
} catch (JournalException e) {
String msg = "Unable to create log entry: " + e.getMessage();
log.error(msg);
} catch (Throwable e) {
String msg = "Unexpected error while creating log entry.";
log.error(msg, e);
} finally {
if (!succeeded && record != null) {
record.cancelUpdate();
}
}
}
/**
* Invoked when a cluster operation has ended. If <code>successful</code>,
* attempts to fill the journal record and update it, otherwise cancels
* the update.
*
* @param operation cluster operation
* @param successful <code>true</code> if the operation was successful and
* the journal record should be updated;
* <code>false</code> to revoke changes
*/
public void ended(DefaultClusterOperation operation, boolean successful) {
ClusterRecord record = operation.getRecord();
boolean succeeded = false;
try {
if (successful) {
record.write();
record.update();
setRevision(record.getRevision());
succeeded = true;
}
} catch (JournalException e) {
String msg = "Unable to create log entry: " + e.getMessage();
log.error(msg);
} catch (Throwable e) {
String msg = "Unexpected error while creating log entry.";
log.error(msg, e);
} finally {
if (!succeeded) {
record.cancelUpdate();
}
}
}
}