/**
* 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.zookeeper.server;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.nio.ByteBuffer;
import org.apache.jute.Index;
import org.apache.jute.InputArchive;
import org.apache.jute.OutputArchive;
import org.apache.jute.Record;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.apache.zookeeper.KeeperException;
import org.apache.zookeeper.Quotas;
import org.apache.zookeeper.StatsTrack;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.KeeperException.Code;
import org.apache.zookeeper.KeeperException.NoNodeException;
import org.apache.zookeeper.Watcher.Event;
import org.apache.zookeeper.Watcher.Event.EventType;
import org.apache.zookeeper.Watcher.Event.KeeperState;
import org.apache.zookeeper.ZooDefs.Ids;
import org.apache.zookeeper.ZooDefs.OpCode;
import org.apache.zookeeper.common.PathTrie;
import org.apache.zookeeper.data.ACL;
import org.apache.zookeeper.data.Stat;
import org.apache.zookeeper.data.StatPersisted;
import org.apache.zookeeper.txn.CreateTxn;
import org.apache.zookeeper.txn.DeleteTxn;
import org.apache.zookeeper.txn.ErrorTxn;
import org.apache.zookeeper.txn.SetACLTxn;
import org.apache.zookeeper.txn.SetDataTxn;
import org.apache.zookeeper.txn.CheckVersionTxn;
import org.apache.zookeeper.txn.Txn;
import org.apache.zookeeper.txn.MultiTxn;
import org.apache.zookeeper.txn.TxnHeader;
import org.apache.zookeeper.proto.CreateRequest;
import org.apache.zookeeper.proto.DeleteRequest;
import org.apache.zookeeper.proto.SetACLRequest;
import org.apache.zookeeper.proto.SetDataRequest;
/**
* This class maintains the tree data structure. It doesn't have any networking
* or client connection code in it so that it can be tested in a stand alone
* way.
* <p>
* The tree maintains two parallel data structures: a hashtable that maps from
* full paths to DataNodes and a tree of DataNodes. All accesses to a path is
* through the hashtable. The tree is traversed only when serializing to disk.
*/
public class DataTree {
private static final Logger LOG = LoggerFactory.getLogger(DataTree.class);
/**
* This hashtable provides a fast lookup to the datanodes. The tree is the
* source of truth and is where all the locking occurs
*/
private final ConcurrentHashMap<String, DataNode> nodes =
new ConcurrentHashMap<String, DataNode>();
private final WatchManager dataWatches = new WatchManager();
private final WatchManager childWatches = new WatchManager();
/** the root of zookeeper tree */
private static final String rootZookeeper = "/";
/** the zookeeper nodes that acts as the management and status node **/
private static final String procZookeeper = Quotas.procZookeeper;
/** this will be the string thats stored as a child of root */
private static final String procChildZookeeper = procZookeeper.substring(1);
/**
* the zookeeper quota node that acts as the quota management node for
* zookeeper
*/
private static final String quotaZookeeper = Quotas.quotaZookeeper;
/** this will be the string thats stored as a child of /zookeeper */
private static final String quotaChildZookeeper = quotaZookeeper
.substring(procZookeeper.length() + 1);
/**
* the path trie that keeps track fo the quota nodes in this datatree
*/
private final PathTrie pTrie = new PathTrie();
/**
* This hashtable lists the paths of the ephemeral nodes of a session.
*/
private final Map<Long, HashSet<String>> ephemerals =
new ConcurrentHashMap<Long, HashSet<String>>();
/**
* this is map from longs to acl's. It saves acl's being stored for each
* datanode.
*/
public final Map<Long, List<ACL>> longKeyMap =
new HashMap<Long, List<ACL>>();
/**
* this a map from acls to long.
*/
public final Map<List<ACL>, Long> aclKeyMap =
new HashMap<List<ACL>, Long>();
/**
* these are the number of acls that we have in the datatree
*/
protected long aclIndex = 0;
@SuppressWarnings("unchecked")
public HashSet<String> getEphemerals(long sessionId) {
HashSet<String> retv = ephemerals.get(sessionId);
if (retv == null) {
return new HashSet<String>();
}
HashSet<String> cloned = null;
synchronized (retv) {
cloned = (HashSet<String>) retv.clone();
}
return cloned;
}
public Map<Long, HashSet<String>> getEphemeralsMap() {
return ephemerals;
}
private long incrementIndex() {
return ++aclIndex;
}
/**
* compare two list of acls. if there elements are in the same order and the
* same size then return true else return false
*
* @param lista
* the list to be compared
* @param listb
* the list to be compared
* @return true if and only if the lists are of the same size and the
* elements are in the same order in lista and listb
*/
private boolean listACLEquals(List<ACL> lista, List<ACL> listb) {
if (lista.size() != listb.size()) {
return false;
}
for (int i = 0; i < lista.size(); i++) {
ACL a = lista.get(i);
ACL b = listb.get(i);
if (!a.equals(b)) {
return false;
}
}
return true;
}
/**
* converts the list of acls to a list of longs.
*
* @param acls
* @return a list of longs that map to the acls
*/
public synchronized Long convertAcls(List<ACL> acls) {
if (acls == null)
return -1L;
// get the value from the map
Long ret = aclKeyMap.get(acls);
// could not find the map
if (ret != null)
return ret;
long val = incrementIndex();
longKeyMap.put(val, acls);
aclKeyMap.put(acls, val);
return val;
}
/**
* converts a list of longs to a list of acls.
*
* @param longs
* the list of longs
* @return a list of ACLs that map to longs
*/
public synchronized List<ACL> convertLong(Long longVal) {
if (longVal == null)
return null;
if (longVal == -1L)
return Ids.OPEN_ACL_UNSAFE;
List<ACL> acls = longKeyMap.get(longVal);
if (acls == null) {
LOG.error("ERROR: ACL not available for long " + longVal);
throw new RuntimeException("Failed to fetch acls for " + longVal);
}
return acls;
}
public Collection<Long> getSessions() {
return ephemerals.keySet();
}
/**
* just an accessor method to allow raw creation of datatree's from a bunch
* of datanodes
*
* @param path
* the path of the datanode
* @param node
* the datanode corresponding to this path
*/
public void addDataNode(String path, DataNode node) {
nodes.put(path, node);
}
public DataNode getNode(String path) {
return nodes.get(path);
}
public int getNodeCount() {
return nodes.size();
}
public int getWatchCount() {
return dataWatches.size() + childWatches.size();
}
public int getEphemeralsCount() {
Map<Long, HashSet<String>> map = this.getEphemeralsMap();
int result = 0;
for (HashSet<String> set : map.values()) {
result += set.size();
}
return result;
}
/**
* Get the size of the nodes based on path and data length.
*
* @return size of the data
*/
public long approximateDataSize() {
long result = 0;
for (Map.Entry<String, DataNode> entry : nodes.entrySet()) {
DataNode value = entry.getValue();
synchronized (value) {
result += entry.getKey().length();
result += (value.data == null ? 0
: value.data.length);
}
}
return result;
}
/**
* This is a pointer to the root of the DataTree. It is the source of truth,
* but we usually use the nodes hashmap to find nodes in the tree.
*/
private DataNode root = new DataNode(null, new byte[0], -1L,
new StatPersisted());
/**
* create a /zookeeper filesystem that is the proc filesystem of zookeeper
*/
private DataNode procDataNode = new DataNode(root, new byte[0], -1L,
new StatPersisted());
/**
* create a /zookeeper/quota node for maintaining quota properties for
* zookeeper
*/
private DataNode quotaDataNode = new DataNode(procDataNode, new byte[0],
-1L, new StatPersisted());
public DataTree() {
/* Rather than fight it, let root have an alias */
nodes.put("", root);
nodes.put(rootZookeeper, root);
/** add the proc node and quota node */
root.addChild(procChildZookeeper);
nodes.put(procZookeeper, procDataNode);
procDataNode.addChild(quotaChildZookeeper);
nodes.put(quotaZookeeper, quotaDataNode);
}
/**
* is the path one of the special paths owned by zookeeper.
*
* @param path
* the path to be checked
* @return true if a special path. false if not.
*/
boolean isSpecialPath(String path) {
if (rootZookeeper.equals(path) || procZookeeper.equals(path)
|| quotaZookeeper.equals(path)) {
return true;
}
return false;
}
static public void copyStatPersisted(StatPersisted from, StatPersisted to) {
to.setAversion(from.getAversion());
to.setCtime(from.getCtime());
to.setCversion(from.getCversion());
to.setCzxid(from.getCzxid());
to.setMtime(from.getMtime());
to.setMzxid(from.getMzxid());
to.setPzxid(from.getPzxid());
to.setVersion(from.getVersion());
to.setEphemeralOwner(from.getEphemeralOwner());
}
static public void copyStat(Stat from, Stat to) {
to.setAversion(from.getAversion());
to.setCtime(from.getCtime());
to.setCversion(from.getCversion());
to.setCzxid(from.getCzxid());
to.setMtime(from.getMtime());
to.setMzxid(from.getMzxid());
to.setPzxid(from.getPzxid());
to.setVersion(from.getVersion());
to.setEphemeralOwner(from.getEphemeralOwner());
to.setDataLength(from.getDataLength());
to.setNumChildren(from.getNumChildren());
}
/**
* update the count of this stat datanode
*
* @param lastPrefix
* the path of the node that is quotaed.
* @param diff
* the diff to be added to the count
*/
public void updateCount(String lastPrefix, int diff) {
String statNode = Quotas.statPath(lastPrefix);
DataNode node = nodes.get(statNode);
StatsTrack updatedStat = null;
if (node == null) {
// should not happen
LOG.error("Missing count node for stat " + statNode);
return;
}
synchronized (node) {
updatedStat = new StatsTrack(new String(node.data));
updatedStat.setCount(updatedStat.getCount() + diff);
node.data = updatedStat.toString().getBytes();
}
// now check if the counts match the quota
String quotaNode = Quotas.quotaPath(lastPrefix);
node = nodes.get(quotaNode);
StatsTrack thisStats = null;
if (node == null) {
// should not happen
LOG.error("Missing count node for quota " + quotaNode);
return;
}
synchronized (node) {
thisStats = new StatsTrack(new String(node.data));
}
if (thisStats.getCount() > -1 && (thisStats.getCount() < updatedStat.getCount())) {
LOG
.warn("Quota exceeded: " + lastPrefix + " count="
+ updatedStat.getCount() + " limit="
+ thisStats.getCount());
}
}
/**
* update the count of bytes of this stat datanode
*
* @param lastPrefix
* the path of the node that is quotaed
* @param diff
* the diff to added to number of bytes
* @throws IOException
* if path is not found
*/
public void updateBytes(String lastPrefix, long diff) {
String statNode = Quotas.statPath(lastPrefix);
DataNode node = nodes.get(statNode);
if (node == null) {
// should never be null but just to make
// findbugs happy
LOG.error("Missing stat node for bytes " + statNode);
return;
}
StatsTrack updatedStat = null;
synchronized (node) {
updatedStat = new StatsTrack(new String(node.data));
updatedStat.setBytes(updatedStat.getBytes() + diff);
node.data = updatedStat.toString().getBytes();
}
// now check if the bytes match the quota
String quotaNode = Quotas.quotaPath(lastPrefix);
node = nodes.get(quotaNode);
if (node == null) {
// should never be null but just to make
// findbugs happy
LOG.error("Missing quota node for bytes " + quotaNode);
return;
}
StatsTrack thisStats = null;
synchronized (node) {
thisStats = new StatsTrack(new String(node.data));
}
if (thisStats.getBytes() > -1 && (thisStats.getBytes() < updatedStat.getBytes())) {
LOG
.warn("Quota exceeded: " + lastPrefix + " bytes="
+ updatedStat.getBytes() + " limit="
+ thisStats.getBytes());
}
}
/**
* @param path
* @param data
* @param acl
* @param ephemeralOwner
* the session id that owns this node. -1 indicates this is not
* an ephemeral node.
* @param zxid
* @param time
* @return the patch of the created node
* @throws KeeperException
*/
public String createNode(String path, byte data[], List<ACL> acl,
long ephemeralOwner, int parentCVersion, long zxid, long time)
throws KeeperException.NoNodeException,
KeeperException.NodeExistsException {
int lastSlash = path.lastIndexOf('/');
String parentName = path.substring(0, lastSlash);
String childName = path.substring(lastSlash + 1);
StatPersisted stat = new StatPersisted();
stat.setCtime(time);
stat.setMtime(time);
stat.setCzxid(zxid);
stat.setMzxid(zxid);
stat.setPzxid(zxid);
stat.setVersion(0);
stat.setAversion(0);
stat.setEphemeralOwner(ephemeralOwner);
DataNode parent = nodes.get(parentName);
if (parent == null) {
throw new KeeperException.NoNodeException();
}
synchronized (parent) {
Set<String> children = parent.getChildren();
if (children != null) {
if (children.contains(childName)) {
throw new KeeperException.NodeExistsException();
}
}
if (parentCVersion == -1) {
parentCVersion = parent.stat.getCversion();
parentCVersion++;
}
parent.stat.setCversion(parentCVersion);
parent.stat.setPzxid(zxid);
Long longval = convertAcls(acl);
DataNode child = new DataNode(parent, data, longval, stat);
parent.addChild(childName);
nodes.put(path, child);
if (ephemeralOwner != 0) {
HashSet<String> list = ephemerals.get(ephemeralOwner);
if (list == null) {
list = new HashSet<String>();
ephemerals.put(ephemeralOwner, list);
}
synchronized (list) {
list.add(path);
}
}
}
// now check if its one of the zookeeper node child
if (parentName.startsWith(quotaZookeeper)) {
// now check if its the limit node
if (Quotas.limitNode.equals(childName)) {
// this is the limit node
// get the parent and add it to the trie
pTrie.addPath(parentName.substring(quotaZookeeper.length()));
}
if (Quotas.statNode.equals(childName)) {
updateQuotaForPath(parentName
.substring(quotaZookeeper.length()));
}
}
// also check to update the quotas for this node
String lastPrefix;
if((lastPrefix = getMaxPrefixWithQuota(path)) != null) {
// ok we have some match and need to update
updateCount(lastPrefix, 1);
updateBytes(lastPrefix, data == null ? 0 : data.length);
}
dataWatches.triggerWatch(path, Event.EventType.NodeCreated);
childWatches.triggerWatch(parentName.equals("") ? "/" : parentName,
Event.EventType.NodeChildrenChanged);
return path;
}
/**
* remove the path from the datatree
*
* @param path
* the path to of the node to be deleted
* @param zxid
* the current zxid
* @throws KeeperException.NoNodeException
*/
public void deleteNode(String path, long zxid)
throws KeeperException.NoNodeException {
int lastSlash = path.lastIndexOf('/');
String parentName = path.substring(0, lastSlash);
String childName = path.substring(lastSlash + 1);
DataNode node = nodes.get(path);
if (node == null) {
throw new KeeperException.NoNodeException();
}
nodes.remove(path);
DataNode parent = nodes.get(parentName);
if (parent == null) {
throw new KeeperException.NoNodeException();
}
synchronized (parent) {
parent.removeChild(childName);
parent.stat.setPzxid(zxid);
long eowner = node.stat.getEphemeralOwner();
if (eowner != 0) {
HashSet<String> nodes = ephemerals.get(eowner);
if (nodes != null) {
synchronized (nodes) {
nodes.remove(path);
}
}
}
node.parent = null;
}
if (parentName.startsWith(procZookeeper)) {
// delete the node in the trie.
if (Quotas.limitNode.equals(childName)) {
// we need to update the trie
// as well
pTrie.deletePath(parentName.substring(quotaZookeeper.length()));
}
}
// also check to update the quotas for this node
String lastPrefix;
if((lastPrefix = getMaxPrefixWithQuota(path)) != null) {
// ok we have some match and need to update
updateCount(lastPrefix, -1);
int bytes = 0;
synchronized (node) {
bytes = (node.data == null ? 0 : -(node.data.length));
}
updateBytes(lastPrefix, bytes);
}
if (LOG.isTraceEnabled()) {
ZooTrace.logTraceMessage(LOG, ZooTrace.EVENT_DELIVERY_TRACE_MASK,
"dataWatches.triggerWatch " + path);
ZooTrace.logTraceMessage(LOG, ZooTrace.EVENT_DELIVERY_TRACE_MASK,
"childWatches.triggerWatch " + parentName);
}
Set<Watcher> processed = dataWatches.triggerWatch(path,
EventType.NodeDeleted);
childWatches.triggerWatch(path, EventType.NodeDeleted, processed);
childWatches.triggerWatch(parentName.equals("") ? "/" : parentName,
EventType.NodeChildrenChanged);
}
public Stat setData(String path, byte data[], int version, long zxid,
long time) throws KeeperException.NoNodeException {
Stat s = new Stat();
DataNode n = nodes.get(path);
if (n == null) {
throw new KeeperException.NoNodeException();
}
byte lastdata[] = null;
synchronized (n) {
lastdata = n.data;
n.data = data;
n.stat.setMtime(time);
n.stat.setMzxid(zxid);
n.stat.setVersion(version);
n.copyStat(s);
}
// now update if the path is in a quota subtree.
String lastPrefix;
if((lastPrefix = getMaxPrefixWithQuota(path)) != null) {
this.updateBytes(lastPrefix, (data == null ? 0 : data.length)
- (lastdata == null ? 0 : lastdata.length));
}
dataWatches.triggerWatch(path, EventType.NodeDataChanged);
return s;
}
/**
* If there is a quota set, return the appropriate prefix for that quota
* Else return null
* @param The ZK path to check for quota
* @return Max quota prefix, or null if none
*/
public String getMaxPrefixWithQuota(String path) {
// do nothing for the root.
// we are not keeping a quota on the zookeeper
// root node for now.
String lastPrefix = pTrie.findMaxPrefix(path);
if (!rootZookeeper.equals(lastPrefix) && !("".equals(lastPrefix))) {
return lastPrefix;
}
else {
return null;
}
}
public byte[] getData(String path, Stat stat, Watcher watcher)
throws KeeperException.NoNodeException {
DataNode n = nodes.get(path);
if (n == null) {
throw new KeeperException.NoNodeException();
}
synchronized (n) {
n.copyStat(stat);
if (watcher != null) {
dataWatches.addWatch(path, watcher);
}
return n.data;
}
}
public Stat statNode(String path, Watcher watcher)
throws KeeperException.NoNodeException {
Stat stat = new Stat();
DataNode n = nodes.get(path);
if (watcher != null) {
dataWatches.addWatch(path, watcher);
}
if (n == null) {
throw new KeeperException.NoNodeException();
}
synchronized (n) {
n.copyStat(stat);
return stat;
}
}
public List<String> getChildren(String path, Stat stat, Watcher watcher)
throws KeeperException.NoNodeException {
DataNode n = nodes.get(path);
if (n == null) {
throw new KeeperException.NoNodeException();
}
synchronized (n) {
if (stat != null) {
n.copyStat(stat);
}
ArrayList<String> children;
Set<String> childs = n.getChildren();
if (childs != null) {
children = new ArrayList<String>(childs.size());
children.addAll(childs);
} else {
children = new ArrayList<String>(0);
}
if (watcher != null) {
childWatches.addWatch(path, watcher);
}
return children;
}
}
public Stat setACL(String path, List<ACL> acl, int version)
throws KeeperException.NoNodeException {
Stat stat = new Stat();
DataNode n = nodes.get(path);
if (n == null) {
throw new KeeperException.NoNodeException();
}
synchronized (n) {
n.stat.setAversion(version);
n.acl = convertAcls(acl);
n.copyStat(stat);
return stat;
}
}
@SuppressWarnings("unchecked")
public List<ACL> getACL(String path, Stat stat)
throws KeeperException.NoNodeException {
DataNode n = nodes.get(path);
if (n == null) {
throw new KeeperException.NoNodeException();
}
synchronized (n) {
n.copyStat(stat);
return new ArrayList<ACL>(convertLong(n.acl));
}
}
static public class ProcessTxnResult {
public long clientId;
public int cxid;
public long zxid;
public int err;
public int type;
public String path;
public Stat stat;
public List<ProcessTxnResult> multiResult;
/**
* Equality is defined as the clientId and the cxid being the same. This
* allows us to use hash tables to track completion of transactions.
*
* @see java.lang.Object#equals(java.lang.Object)
*/
@Override
public boolean equals(Object o) {
if (o instanceof ProcessTxnResult) {
ProcessTxnResult other = (ProcessTxnResult) o;
return other.clientId == clientId && other.cxid == cxid;
}
return false;
}
/**
* See equals() to find the rational for how this hashcode is generated.
*
* @see ProcessTxnResult#equals(Object)
* @see java.lang.Object#hashCode()
*/
@Override
public int hashCode() {
return (int) ((clientId ^ cxid) % Integer.MAX_VALUE);
}
}
public volatile long lastProcessedZxid = 0;
public ProcessTxnResult processTxn(TxnHeader header, Record txn)
{
ProcessTxnResult rc = new ProcessTxnResult();
String debug = "";
try {
rc.clientId = header.getClientId();
rc.cxid = header.getCxid();
rc.zxid = header.getZxid();
rc.type = header.getType();
rc.err = 0;
rc.multiResult = null;
switch (header.getType()) {
case OpCode.create:
CreateTxn createTxn = (CreateTxn) txn;
debug = "Create transaction for " + createTxn.getPath();
rc.path = createTxn.getPath();
createNode(
createTxn.getPath(),
createTxn.getData(),
createTxn.getAcl(),
createTxn.getEphemeral() ? header.getClientId() : 0,
createTxn.getParentCVersion(),
header.getZxid(), header.getTime());
break;
case OpCode.delete:
DeleteTxn deleteTxn = (DeleteTxn) txn;
debug = "Delete transaction for " + deleteTxn.getPath();
rc.path = deleteTxn.getPath();
deleteNode(deleteTxn.getPath(), header.getZxid());
break;
case OpCode.setData:
SetDataTxn setDataTxn = (SetDataTxn) txn;
debug = "Set data transaction for "
+ setDataTxn.getPath()
+ " to new value=" + Arrays.toString(setDataTxn.getData());
rc.stat = setData(setDataTxn.getPath(), setDataTxn
.getData(), setDataTxn.getVersion(), header
.getZxid(), header.getTime());
break;
case OpCode.setACL:
SetACLTxn setACLTxn = (SetACLTxn) txn;
debug = "Set ACL transaction for "
+ setACLTxn.getPath();
rc.stat = setACL(setACLTxn.getPath(), setACLTxn.getAcl(),
setACLTxn.getVersion());
break;
case OpCode.closeSession:
killSession(header.getClientId(), header.getZxid());
break;
case OpCode.error:
ErrorTxn errTxn = (ErrorTxn) txn;
rc.err = errTxn.getErr();
break;
case OpCode.check:
CheckVersionTxn checkTxn = (CheckVersionTxn) txn;
debug = "Check Version transaction for "
+ checkTxn.getPath()
+ " and version="
+ checkTxn.getVersion();
rc.path = checkTxn.getPath();
break;
case OpCode.multi:
MultiTxn multiTxn = (MultiTxn) txn ;
List<Txn> txns = multiTxn.getTxns();
debug = "Multi transaction with " + txns.size() + " operations";
rc.multiResult = new ArrayList<ProcessTxnResult>();
boolean failed = false;
for (Txn subtxn : txns) {
if (subtxn.getType() == OpCode.error) {
failed = true;
break;
}
}
boolean post_failed = false;
for (Txn subtxn : txns) {
ByteBuffer bb = ByteBuffer.wrap(subtxn.getData());
Record record = null;
switch (subtxn.getType()) {
case OpCode.create:
record = new CreateTxn();
break;
case OpCode.delete:
record = new DeleteTxn();
break;
case OpCode.setData:
record = new SetDataTxn();
break;
case OpCode.error:
record = new ErrorTxn();
post_failed = true;
break;
case OpCode.check:
record = new CheckVersionTxn();
break;
default:
throw new IOException("Invalid type of op: " + subtxn.getType());
}
assert(record != null);
ByteBufferInputStream.byteBuffer2Record(bb, record);
if (failed && subtxn.getType() != OpCode.error){
int ec = post_failed ? Code.RUNTIMEINCONSISTENCY.intValue()
: Code.OK.intValue();
subtxn.setType(OpCode.error);
record = new ErrorTxn(ec);
}
if (failed) {
assert(subtxn.getType() == OpCode.error) ;
}
TxnHeader subHdr = new TxnHeader(header.getClientId(), header.getCxid(),
header.getZxid(), header.getTime(),
subtxn.getType());
ProcessTxnResult subRc = processTxn(subHdr, record);
rc.multiResult.add(subRc);
if (subRc.err != 0 && rc.err == 0) {
rc.err = subRc.err ;
}
}
break;
}
} catch (KeeperException e) {
LOG.warn("Failed: " + debug, e);
rc.err = e.code().intValue();
} catch (IOException e) {
LOG.warn("Failed:" + debug, e);
}
/*
* A snapshot might be in progress while we are modifying the data
* tree. If we set lastProcessedZxid prior to making corresponding
* change to the tree, then the zxid associated with the snapshot
* file will be ahead of its contents. Thus, while restoring from
* the snapshot, the restore method will not apply the transaction
* for zxid associated with the snapshot file, since the restore
* method assumes that transaction to be present in the snapshot.
*
* To avoid this, we first apply the transaction and then modify
* lastProcessedZxid. During restore, we correctly handle the
* case where the snapshot contains data ahead of the zxid associated
* with the file.
*/
if (rc.zxid > lastProcessedZxid) {
lastProcessedZxid = rc.zxid;
}
return rc;
}
void killSession(long session, long zxid) {
// the list is already removed from the ephemerals
// so we do not have to worry about synchronizing on
// the list. This is only called from FinalRequestProcessor
// so there is no need for synchronization. The list is not
// changed here. Only create and delete change the list which
// are again called from FinalRequestProcessor in sequence.
HashSet<String> list = ephemerals.remove(session);
if (list != null) {
for (String path : list) {
try {
deleteNode(path, zxid);
if (LOG.isDebugEnabled()) {
LOG
.debug("Deleting ephemeral node " + path
+ " for session 0x"
+ Long.toHexString(session));
}
} catch (NoNodeException e) {
LOG.warn("Ignoring NoNodeException for path " + path
+ " while removing ephemeral for dead session 0x"
+ Long.toHexString(session));
}
}
}
}
/**
* a encapsultaing class for return value
*/
private static class Counts {
long bytes;
int count;
}
/**
* this method gets the count of nodes and the bytes under a subtree
*
* @param path
* the path to be used
* @param bytes
* the long bytes
* @param count
* the int count
*/
private void getCounts(String path, Counts counts) {
DataNode node = getNode(path);
if (node == null) {
return;
}
String[] children = null;
int len = 0;
synchronized (node) {
Set<String> childs = node.getChildren();
if (childs != null) {
children = childs.toArray(new String[childs.size()]);
}
len = (node.data == null ? 0 : node.data.length);
}
// add itself
counts.count += 1;
counts.bytes += len;
if (children == null || children.length == 0) {
return;
}
for (String child : children) {
getCounts(path + "/" + child, counts);
}
}
/**
* update the quota for the given path
*
* @param path
* the path to be used
*/
private void updateQuotaForPath(String path) {
Counts c = new Counts();
getCounts(path, c);
StatsTrack strack = new StatsTrack();
strack.setBytes(c.bytes);
strack.setCount(c.count);
String statPath = Quotas.quotaZookeeper + path + "/" + Quotas.statNode;
DataNode node = getNode(statPath);
// it should exist
if (node == null) {
LOG.warn("Missing quota stat node " + statPath);
return;
}
synchronized (node) {
node.data = strack.toString().getBytes();
}
}
/**
* this method traverses the quota path and update the path trie and sets
*
* @param path
*/
private void traverseNode(String path) {
DataNode node = getNode(path);
String children[] = null;
synchronized (node) {
Set<String> childs = node.getChildren();
if (childs != null) {
children = childs.toArray(new String[childs.size()]);
}
}
if (children == null || children.length == 0) {
// this node does not have a child
// is the leaf node
// check if its the leaf node
String endString = "/" + Quotas.limitNode;
if (path.endsWith(endString)) {
// ok this is the limit node
// get the real node and update
// the count and the bytes
String realPath = path.substring(Quotas.quotaZookeeper
.length(), path.indexOf(endString));
updateQuotaForPath(realPath);
this.pTrie.addPath(realPath);
}
return;
}
for (String child : children) {
traverseNode(path + "/" + child);
}
}
/**
* this method sets up the path trie and sets up stats for quota nodes
*/
private void setupQuota() {
String quotaPath = Quotas.quotaZookeeper;
DataNode node = getNode(quotaPath);
if (node == null) {
return;
}
traverseNode(quotaPath);
}
/**
* this method uses a stringbuilder to create a new path for children. This
* is faster than string appends ( str1 + str2).
*
* @param oa
* OutputArchive to write to.
* @param path
* a string builder.
* @throws IOException
* @throws InterruptedException
*/
void serializeNode(OutputArchive oa, StringBuilder path) throws IOException {
String pathString = path.toString();
DataNode node = getNode(pathString);
if (node == null) {
return;
}
String children[] = null;
synchronized (node) {
scount++;
oa.writeString(pathString, "path");
oa.writeRecord(node, "node");
Set<String> childs = node.getChildren();
if (childs != null) {
children = childs.toArray(new String[childs.size()]);
}
}
path.append('/');
int off = path.length();
if (children != null) {
for (String child : children) {
// since this is single buffer being resused
// we need
// to truncate the previous bytes of string.
path.delete(off, Integer.MAX_VALUE);
path.append(child);
serializeNode(oa, path);
}
}
}
int scount;
public boolean initialized = false;
private void deserializeList(Map<Long, List<ACL>> longKeyMap,
InputArchive ia) throws IOException {
int i = ia.readInt("map");
while (i > 0) {
Long val = ia.readLong("long");
if (aclIndex < val) {
aclIndex = val;
}
List<ACL> aclList = new ArrayList<ACL>();
Index j = ia.startVector("acls");
while (!j.done()) {
ACL acl = new ACL();
acl.deserialize(ia, "acl");
aclList.add(acl);
j.incr();
}
longKeyMap.put(val, aclList);
aclKeyMap.put(aclList, val);
i--;
}
}
private synchronized void serializeList(Map<Long, List<ACL>> longKeyMap,
OutputArchive oa) throws IOException {
oa.writeInt(longKeyMap.size(), "map");
Set<Map.Entry<Long, List<ACL>>> set = longKeyMap.entrySet();
for (Map.Entry<Long, List<ACL>> val : set) {
oa.writeLong(val.getKey(), "long");
List<ACL> aclList = val.getValue();
oa.startVector(aclList, "acls");
for (ACL acl : aclList) {
acl.serialize(oa, "acl");
}
oa.endVector(aclList, "acls");
}
}
public void serialize(OutputArchive oa, String tag) throws IOException {
scount = 0;
serializeList(longKeyMap, oa);
serializeNode(oa, new StringBuilder(""));
// / marks end of stream
// we need to check if clear had been called in between the snapshot.
if (root != null) {
oa.writeString("/", "path");
}
}
public void deserialize(InputArchive ia, String tag) throws IOException {
deserializeList(longKeyMap, ia);
nodes.clear();
String path = ia.readString("path");
while (!path.equals("/")) {
DataNode node = new DataNode();
ia.readRecord(node, "node");
nodes.put(path, node);
int lastSlash = path.lastIndexOf('/');
if (lastSlash == -1) {
root = node;
} else {
String parentPath = path.substring(0, lastSlash);
node.parent = nodes.get(parentPath);
if (node.parent == null) {
throw new IOException("Invalid Datatree, unable to find " +
"parent " + parentPath + " of path " + path);
}
node.parent.addChild(path.substring(lastSlash + 1));
long eowner = node.stat.getEphemeralOwner();
if (eowner != 0) {
HashSet<String> list = ephemerals.get(eowner);
if (list == null) {
list = new HashSet<String>();
ephemerals.put(eowner, list);
}
list.add(path);
}
}
path = ia.readString("path");
}
nodes.put("/", root);
// we are done with deserializing the
// the datatree
// update the quotas - create path trie
// and also update the stat nodes
setupQuota();
}
/**
* Summary of the watches on the datatree.
* @param pwriter the output to write to
*/
public synchronized void dumpWatchesSummary(PrintWriter pwriter) {
pwriter.print(dataWatches.toString());
}
/**
* Write a text dump of all the watches on the datatree.
* Warning, this is expensive, use sparingly!
* @param pwriter the output to write to
*/
public synchronized void dumpWatches(PrintWriter pwriter, boolean byPath) {
dataWatches.dumpWatches(pwriter, byPath);
}
/**
* Write a text dump of all the ephemerals in the datatree.
* @param pwriter the output to write to
*/
public void dumpEphemerals(PrintWriter pwriter) {
Set<Long> keys = ephemerals.keySet();
pwriter.println("Sessions with Ephemerals ("
+ keys.size() + "):");
for (long k : keys) {
pwriter.print("0x" + Long.toHexString(k));
pwriter.println(":");
HashSet<String> tmp = ephemerals.get(k);
synchronized (tmp) {
for (String path : tmp) {
pwriter.println("\t" + path);
}
}
}
}
public void removeCnxn(Watcher watcher) {
dataWatches.removeWatcher(watcher);
childWatches.removeWatcher(watcher);
}
public void clear() {
root = null;
nodes.clear();
ephemerals.clear();
// dataWatches = null;
// childWatches = null;
}
public void setWatches(long relativeZxid, List<String> dataWatches,
List<String> existWatches, List<String> childWatches,
Watcher watcher) {
for (String path : dataWatches) {
DataNode node = getNode(path);
WatchedEvent e = null;
if (node == null) {
e = new WatchedEvent(EventType.NodeDeleted,
KeeperState.SyncConnected, path);
} else if (node.stat.getCzxid() > relativeZxid) {
e = new WatchedEvent(EventType.NodeCreated,
KeeperState.SyncConnected, path);
} else if (node.stat.getMzxid() > relativeZxid) {
e = new WatchedEvent(EventType.NodeDataChanged,
KeeperState.SyncConnected, path);
}
if (e != null) {
watcher.process(e);
} else {
this.dataWatches.addWatch(path, watcher);
}
}
for (String path : existWatches) {
DataNode node = getNode(path);
WatchedEvent e = null;
if (node == null) {
// This is the case when the watch was registered
} else if (node.stat.getMzxid() > relativeZxid) {
e = new WatchedEvent(EventType.NodeDataChanged,
KeeperState.SyncConnected, path);
} else {
e = new WatchedEvent(EventType.NodeCreated,
KeeperState.SyncConnected, path);
}
if (e != null) {
watcher.process(e);
} else {
this.dataWatches.addWatch(path, watcher);
}
}
for (String path : childWatches) {
DataNode node = getNode(path);
WatchedEvent e = null;
if (node == null) {
e = new WatchedEvent(EventType.NodeDeleted,
KeeperState.SyncConnected, path);
} else if (node.stat.getPzxid() > relativeZxid) {
e = new WatchedEvent(EventType.NodeChildrenChanged,
KeeperState.SyncConnected, path);
}
if (e != null) {
watcher.process(e);
} else {
this.childWatches.addWatch(path, watcher);
}
}
}
/**
* This method sets the Cversion and Pzxid for the specified node to the
* values passed as arguments. The values are modified only if newCversion
* is greater than the current Cversion. A NoNodeException is thrown if
* a znode for the specified path is not found.
*
* @param path
* Full path to the znode whose Cversion needs to be modified.
* A "/" at the end of the path is ignored.
* @param newCversion
* Value to be assigned to Cversion
* @param zxid
* Value to be assigned to Pzxid
* @throws KeeperException.NoNodeException
* If znode not found.
**/
public void setCversionPzxid(String path, int newCversion, long zxid)
throws KeeperException.NoNodeException {
if (path.endsWith("/")) {
path = path.substring(0, path.length() - 1);
}
DataNode node = nodes.get(path);
if (node == null) {
throw new KeeperException.NoNodeException(path);
}
synchronized (node) {
if(newCversion == -1) {
newCversion = node.stat.getCversion() + 1;
}
if (newCversion > node.stat.getCversion()) {
node.stat.setCversion(newCversion);
node.stat.setPzxid(zxid);
}
}
}
}