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The msm core, provides java serialization strategy.
/*
* Copyright 2011 Martin Grotzke
*
* Licensed 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 de.javakaffee.web.msm;
import static de.javakaffee.web.msm.Configurations.NODE_AVAILABILITY_CACHE_TTL_KEY;
import static de.javakaffee.web.msm.Configurations.getSystemProperty;
import java.net.InetSocketAddress;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import javax.annotation.CheckForNull;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import org.apache.juli.logging.Log;
import org.apache.juli.logging.LogFactory;
import de.javakaffee.web.msm.NodeAvailabilityCache.CacheLoader;
/**
*
* @author Martin Grotzke
*/
public class MemcachedNodesManager {
/**
* Provides queries to memcached.
*/
public static interface MemcachedClientCallback {
/**
* Must query the given key in memcached.
*/
@Nullable
Object get(@Nonnull String key);
}
private static final Log LOG = LogFactory.getLog(MemcachedNodesManager.class);
private static final String NODE_REGEX = "([\\w]+):([^:]+):([\\d]+)";
private static final Pattern NODE_PATTERN = Pattern.compile( NODE_REGEX );
private static final String NODES_REGEX = NODE_REGEX + "(?:(?:\\s+|,)" + NODE_REGEX + ")*";
private static final Pattern NODES_PATTERN = Pattern.compile( NODES_REGEX );
private static final String SINGLE_NODE_REGEX = "([^:]+):([\\d]+)";
private static final Pattern SINGLE_NODE_PATTERN = Pattern.compile( SINGLE_NODE_REGEX );
private static final String COUCHBASE_BUCKET_NODE_REGEX = "http://([^:]+):([\\d]+)/[\\w]+";
private static final Pattern COUCHBASE_BUCKET_NODE_PATTERN = Pattern.compile( COUCHBASE_BUCKET_NODE_REGEX );
private static final String COUCHBASE_BUCKET_NODES_REGEX = COUCHBASE_BUCKET_NODE_REGEX + "(?:(?:\\s+|,)" + COUCHBASE_BUCKET_NODE_REGEX + ")*";
private static final Pattern COUCHBASE_BUCKET_NODES_PATTERN = Pattern.compile( COUCHBASE_BUCKET_NODES_REGEX );
private static final int NODE_AVAILABILITY_CACHE_TTL = getSystemProperty(NODE_AVAILABILITY_CACHE_TTL_KEY, 1000);
private final String _memcachedNodes;
private final NodeIdList _primaryNodeIds;
private final List _failoverNodeIds;
private final LinkedHashMap _address2Ids;
private final boolean _encodeNodeIdInSessionId;
private final StorageKeyFormat _storageKeyFormat;
@Nullable
private NodeIdService _nodeIdService;
private SessionIdFormat _sessionIdFormat;
/**
*
* @param memcachedNodes the original memcachedNodes configuration string
* @param primaryNodeIds the list of primary node ids (memcachedNodes without failoverNodes).
* @param failoverNodeIds the configured failover node ids.
* @param address2Ids a mapping of inet addresses from the memcachedNodes configuration to their node ids.
* @param storageKeyFormat the storage key format
* @param memcachedClientCallback a callback to memcached, can only be null if the memcachedNodes config
* contains a single node without node id.
*/
public MemcachedNodesManager(final String memcachedNodes, @Nonnull final NodeIdList primaryNodeIds, @Nonnull final List failoverNodeIds,
@Nonnull final LinkedHashMap address2Ids,
@Nullable final StorageKeyFormat storageKeyFormat, @Nullable final MemcachedClientCallback memcachedClientCallback) {
_memcachedNodes = memcachedNodes;
_primaryNodeIds = primaryNodeIds;
_failoverNodeIds = failoverNodeIds;
_address2Ids = address2Ids;
_storageKeyFormat = storageKeyFormat;
_encodeNodeIdInSessionId = !((getCountNodes() <= 1 || isCouchbaseConfig(memcachedNodes)) && _primaryNodeIds.isEmpty());
if (_encodeNodeIdInSessionId) {
if (memcachedClientCallback == null) {
throw new IllegalArgumentException("The MemcachedClientCallback must not be null.");
}
_sessionIdFormat = new SessionIdFormat(storageKeyFormat);
_nodeIdService = new NodeIdService( createNodeAvailabilityCache( getCountNodes(), NODE_AVAILABILITY_CACHE_TTL, memcachedClientCallback ),
primaryNodeIds, failoverNodeIds );
}
else {
_sessionIdFormat = new SessionIdFormat(storageKeyFormat) {
@Override
public boolean isValid(final String sessionId) {
return sessionId != null;
}
@Override
public String createBackupKey(final String origKey) {
throw new UnsupportedOperationException("Not supported for single node configuration without node id.");
}
@Override
public String createSessionId(final String sessionId, final String memcachedId) {
return sessionId;
}
@Override
public String extractMemcachedId(final String sessionId) {
throw new UnsupportedOperationException("Not supported for single node configuration without node id.");
}
};
_nodeIdService = null;
}
}
private boolean isCouchbaseConfig(final String memcachedNodes) {
return memcachedNodes.startsWith("http://");
}
protected NodeAvailabilityCache createNodeAvailabilityCache( final int size, final long ttlInMillis,
@Nonnull final MemcachedClientCallback memcachedClientCallback ) {
return new NodeAvailabilityCache( size, ttlInMillis, new CacheLoader() {
@Override
public boolean isNodeAvailable( final String key ) {
try {
memcachedClientCallback.get(_sessionIdFormat.createSessionId( "ping", key ) );
return true;
} catch ( final Exception e ) {
return false;
}
}
} );
}
/**
* Parses the given memcachedNodes definition and returns of {@link MemcachedNodesManager}.
* Supported memcachedNodes formats:
*
* <hostOrIPAddress>:<port> - e.g. localhost:11211<http://hostOrIPAddress>:<port>/<path> - e.g. http://localhost:8091/pools<nodeId>:<hostOrIPAddress>:<port> - e.g. n1:localhost:11211<nodeId>:<hostOrIPAddress>:<port>([ ,]<nodeId>:<hostOrIPAddress>:<port>)+ - e.g.
*
* n1:localhost:11211,n2:localhost:11212n1:localhost:11211 n2:localhost:11212
*
* @param memcachedNodes
* @param failoverNodes TODO
* @param storageKeyPrefix TODO
* @param memcachedClientCallback TODO
* @return
*/
@Nonnull
public static MemcachedNodesManager createFor(final String memcachedNodes, final String failoverNodes, final StorageKeyFormat storageKeyFormat,
final MemcachedClientCallback memcachedClientCallback) {
if ( memcachedNodes == null || memcachedNodes.trim().isEmpty() ) {
throw new IllegalArgumentException("null or empty memcachedNodes not allowed.");
}
if ( !NODES_PATTERN.matcher( memcachedNodes ).matches() && !SINGLE_NODE_PATTERN.matcher(memcachedNodes).matches()
&& !COUCHBASE_BUCKET_NODES_PATTERN.matcher(memcachedNodes).matches()) {
throw new IllegalArgumentException( "Configured memcachedNodes attribute has wrong format, must match " + NODES_REGEX );
}
final Matcher singleNodeMatcher = SINGLE_NODE_PATTERN.matcher(memcachedNodes);
// we have a linked hashmap to have insertion order for addresses
final LinkedHashMap address2Ids = new LinkedHashMap(1);
/**
* If mutliple nodes are configured
*/
if (singleNodeMatcher.matches()) { // for single
address2Ids.put(getSingleShortNodeDefinition(singleNodeMatcher), null);
}
else if (COUCHBASE_BUCKET_NODES_PATTERN.matcher(memcachedNodes).matches()) { // for couchbase
final Matcher matcher = COUCHBASE_BUCKET_NODE_PATTERN.matcher(memcachedNodes);
while (matcher.find()) {
final String hostname = matcher.group( 1 );
final int port = Integer.parseInt( matcher.group( 2 ) );
address2Ids.put(new InetSocketAddress( hostname, port ), null);
}
if (address2Ids.isEmpty()) {
throw new IllegalArgumentException("All nodes are also configured as failover nodes,"
+ " this is a configuration failure. In this case, you probably want to leave out the failoverNodes.");
}
}
else { // If mutliple nodes are configured
final Matcher matcher = NODE_PATTERN.matcher( memcachedNodes);
while (matcher.find()) {
final Pair nodeInfo = getRegularNodeDefinition(matcher);
address2Ids.put(nodeInfo.getSecond(), nodeInfo.getFirst());
}
if (address2Ids.isEmpty()) {
throw new IllegalArgumentException("All nodes are also configured as failover nodes,"
+ " this is a configuration failure. In this case, you probably want to leave out the failoverNodes.");
}
}
final List failoverNodeIds = initFailoverNodes(failoverNodes, address2Ids.values());
// validate that for a single node there's no failover node specified as this does not make sense.
if(address2Ids.size() == 1 && failoverNodeIds.size() >= 1) {
throw new IllegalArgumentException("For a single memcached node there should/must no failoverNodes be specified.");
}
final NodeIdList primaryNodeIds = new NodeIdList();
for(final Map.Entry address2Id : address2Ids.entrySet()) {
final String nodeId = address2Id.getValue();
if (nodeId != null && !failoverNodeIds.contains(nodeId) ) {
primaryNodeIds.add(nodeId);
}
}
return new MemcachedNodesManager(memcachedNodes, primaryNodeIds, failoverNodeIds, address2Ids, storageKeyFormat, memcachedClientCallback);
}
private static InetSocketAddress getSingleShortNodeDefinition(final Matcher singleNodeMatcher) {
final String hostname = singleNodeMatcher.group(1);
final int port = Integer.parseInt(singleNodeMatcher.group(2));
return new InetSocketAddress(hostname, port);
}
private static Pair getRegularNodeDefinition(final Matcher matcher) {
final String nodeId = matcher.group( 1 );
final String hostname = matcher.group( 2 );
final int port = Integer.parseInt( matcher.group( 3 ) );
final InetSocketAddress address = new InetSocketAddress( hostname, port );
return Pair.of(nodeId, address);
}
private static List initFailoverNodes(final String failoverNodes, final Collection allNodeIds) {
final List failoverNodeIds = new ArrayList();
if ( failoverNodes != null && failoverNodes.trim().length() != 0 ) {
final String[] failoverNodesArray = failoverNodes.split( " |," );
for ( final String failoverNodeId : failoverNodesArray ) {
final String failoverNodeIdTrimmed = failoverNodeId.trim();
if ( !allNodeIds.contains( failoverNodeIdTrimmed ) ) {
throw new IllegalArgumentException( "Invalid failover node id " + failoverNodeIdTrimmed + ": "
+ "not existing in memcachedNodes '" + allNodeIds + "'." );
}
failoverNodeIds.add( failoverNodeIdTrimmed );
}
}
return failoverNodeIds;
}
/**
* Provides the original memcachedNodes configuration string.
*/
public String getMemcachedNodes() {
return _memcachedNodes;
}
/**
* Returns the number of memcached nodes.
*/
public int getCountNodes() {
return _address2Ids.size();
}
/**
* Returns the primary node ids, which are the memcachedNodes that are not specified in failoverNodes.
*/
@Nonnull
public NodeIdList getPrimaryNodeIds() {
return _primaryNodeIds;
}
/**
* Returns the failover node ids as specified by failoverNodes in the config.
*/
@Nonnull
public List getFailoverNodeIds() {
return _failoverNodeIds;
}
/**
* Specifies if the memcached node id shall be encoded in the sessionId. This is only false
* for a single memcachedNode definition without a nodeId (e.g. localhost:11211)
* or for couchbase REST URIs (one or more of e.g. http://10.10.0.1:8091/pools).
*/
public boolean isEncodeNodeIdInSessionId() {
return _encodeNodeIdInSessionId;
}
/**
* Return the nodeId for the given socket address. Returns null
* if the socket address is not known.
* @throws IllegalArgumentException thrown when the socketAddress is null or not registered with this {@link MemcachedNodesManager}.
*/
@Nonnull
public String getNodeId(final InetSocketAddress socketAddress) throws IllegalArgumentException {
if ( socketAddress == null ) {
throw new IllegalArgumentException("SocketAddress must not be null.");
}
final String result = _address2Ids.get( socketAddress );
if ( result == null ) {
throw new IllegalArgumentException("SocketAddress " + socketAddress + " not known (registered addresses: " + _address2Ids.keySet() + ").");
}
return result;
}
/**
* Get the next node id for the given one, based on the primary node ids (memcachedNodes without failoverNodes).
* For the last node id the first one is returned.
* If this list contains only a single node, conceptionally there's no next node
* so that null is returned.
* @return the next node id or null if there's no next node id.
* @throws IllegalArgumentException thrown if the given nodeId is not part of this list.
*/
@CheckForNull
public String getNextPrimaryNodeId(final String nodeId) {
return _primaryNodeIds.getNextNodeId(nodeId);
}
/**
* Get the next available node id for the given one, based on the primary node ids
* (memcachedNodes without failoverNodes). For the last node id the first one is returned.
* If this list contains only a single node, conceptionally there's no next node
* so that null is returned.
* @return the next available node id or null if there's no next available node id.
* @see #getNextPrimaryNodeId(String)
* @see #isNodeAvailable(String)
*/
public String getNextAvailableNodeId(final String nodeId) {
String result = nodeId;
do {
result = _primaryNodeIds.getNextNodeId(result);
if(result != null && result.equals(nodeId)) {
result = null;
}
} while(result != null && !isNodeAvailable(result));
return result;
}
/**
* Provides access to the {@link SessionIdFormat} handling sessionIds for this memcached Nodes configuration.
*/
@Nonnull
public SessionIdFormat getSessionIdFormat() {
return _sessionIdFormat;
}
/**
* Provides the {@link StorageKeyFormat} to create the storage key.
*/
@Nonnull
public StorageKeyFormat getStorageKeyFormat() {
return _storageKeyFormat;
}
/**
* Must return all known memcached addresses.
*/
@Nonnull
public List getAllMemcachedAddresses() {
return new ArrayList( _address2Ids.keySet() );
}
/**
* Creates a new sessionId based on the given one, usually by appending a randomly selected memcached node id.
* If the memcachedNodes were configured using a single node without nodeId, the sessionId is returned unchanged.
*/
@Nonnull
public String createSessionId( @Nonnull final String sessionId ) {
return isEncodeNodeIdInSessionId() ? _sessionIdFormat.createSessionId(sessionId, _nodeIdService.getMemcachedNodeId() ) : sessionId;
}
/**
* Mark the given nodeId as available as specified.
* @param nodeId the nodeId to update
* @param available specifies if the node was abailable or not
*/
public void setNodeAvailable(@Nullable final String nodeId, final boolean available) {
if ( _nodeIdService != null ) {
_nodeIdService.setNodeAvailable(nodeId, available);
}
}
/**
* Determines, if the given nodeId is available.
* @param nodeId the node to check, not null.
* @return true, if the node is marked as available
*/
public boolean isNodeAvailable(final String nodeId) {
return _nodeIdService.isNodeAvailable(nodeId);
}
/**
* Can be used to determine if the given sessionId can be used to interact with memcached.
* @see #canHitMemcached(String)
*/
public boolean isValidForMemcached(final String sessionId) {
if ( isEncodeNodeIdInSessionId() ) {
final String nodeId = _sessionIdFormat.extractMemcachedId( sessionId );
if ( nodeId == null ) {
LOG.debug( "The sessionId does not contain a nodeId so that the memcached node could not be identified." );
return false;
}
}
return true;
}
/**
* Can be used to determine if the given sessionId can be used to interact with memcached.
* This also checks if the related memcached is available.
* @see #isValidForMemcached(String)
*/
public boolean canHitMemcached(final String sessionId) {
if ( isEncodeNodeIdInSessionId() ) {
final String nodeId = _sessionIdFormat.extractMemcachedId( sessionId );
if ( nodeId == null ) {
LOG.debug( "The sessionId does not contain a nodeId so that the memcached node could not be identified." );
return false;
}
if ( !_nodeIdService.isNodeAvailable( nodeId ) ) {
LOG.debug( "The node "+ nodeId +" is not available, therefore " + sessionId + " cannot be loaded from this memcached." );
return false;
}
}
return true;
}
public void onLoadFromMemcachedSuccess(final String sessionId) {
setNodeAvailableForSessionId(sessionId, true);
}
public void onLoadFromMemcachedFailure(final String sessionId) {
setNodeAvailableForSessionId(sessionId, false);
}
/**
* Mark the memcached node encoded in the given sessionId as available or not. If nodeIds shall
* not be encoded in the sessionId or if the given sessionId does not contain a nodeId no
* action will be taken.
*
* @param sessionId the sessionId that may contain a node id.
* @param available specifies if the possibly referenced node is available or not.
*
* @return the extracted nodeId or null.
*
* @see #isEncodeNodeIdInSessionId()
*/
public String setNodeAvailableForSessionId(final String sessionId, final boolean available) {
if ( _nodeIdService != null && isEncodeNodeIdInSessionId() ) {
final String nodeId = _sessionIdFormat.extractMemcachedId(sessionId);
if ( nodeId != null ) {
_nodeIdService.setNodeAvailable(nodeId, available);
return nodeId;
}
else {
LOG.warn("Got sessionId without nodeId: " + sessionId);
}
}
return null;
}
/**
* Returns a new session id if node information shall be encoded in the session id
* and the encoded nodeId given one is null or not available.
* @param sessionId the session id that is checked.
* @return a new session id or null.
*/
public String getNewSessionIdIfNodeFromSessionIdUnavailable( @Nonnull final String sessionId ) {
if ( isEncodeNodeIdInSessionId() ) {
final String nodeId = _sessionIdFormat.extractMemcachedId( sessionId );
final String newNodeId = _nodeIdService.getNewNodeIdIfUnavailable( nodeId );
if ( newNodeId != null ) {
return _sessionIdFormat.createNewSessionId( sessionId, newNodeId);
}
}
return null;
}
/**
* Changes the sessionId by setting the given jvmRoute and replacing the memcachedNodeId if it's currently
* set to a failoverNodeId.
* @param sessionId the current session id
* @param jvmRoute the new jvmRoute to set.
* @return the session id with maybe new jvmRoute and/or new memcachedId.
*/
public String changeSessionIdForTomcatFailover( @Nonnull final String sessionId, final String jvmRoute ) {
final String newSessionId = jvmRoute != null && !jvmRoute.trim().isEmpty()
? _sessionIdFormat.changeJvmRoute( sessionId, jvmRoute )
: _sessionIdFormat.stripJvmRoute(sessionId);
if ( isEncodeNodeIdInSessionId() ) {
final String nodeId = _sessionIdFormat.extractMemcachedId( newSessionId );
if(_failoverNodeIds != null && _failoverNodeIds.contains(nodeId)) {
final String newNodeId = _nodeIdService.getAvailableNodeId( nodeId );
if ( newNodeId != null ) {
return _sessionIdFormat.createNewSessionId( newSessionId, newNodeId);
}
}
}
return newSessionId;
}
/**
* Determines, if the current memcachedNodes configuration is a couchbase bucket configuration
* (like e.g. http://10.10.0.1:8091/pools).
*/
public boolean isCouchbaseBucketConfig() {
return COUCHBASE_BUCKET_NODES_PATTERN.matcher(_memcachedNodes).matches();
}
/**
* Returns a list of couchbase REST interface uris if the current configuration is
* a couchbase bucket configuration.
* @see #isCouchbaseBucketConfig()
*/
public List getCouchbaseBucketURIs() {
if(!isCouchbaseBucketConfig())
throw new IllegalStateException("This is not a couchbase bucket configuration.");
final List result = new ArrayList(_address2Ids.size());
final Matcher matcher = COUCHBASE_BUCKET_NODE_PATTERN.matcher(_memcachedNodes);
while (matcher.find()) {
try {
result.add(new URI(matcher.group()));
} catch (final URISyntaxException e) {
throw new RuntimeException(e);
}
}
return result;
}
}