/**
* Creates the serialized value of the object and stores this in ZooKeeper under the path. It
* updates the lastStatusVersion. It does not set a watcher for the path.
*/
private void updateCoordinateData() throws CoordinateMissingException, CloudnameException {
if (!started.get()) {
throw new IllegalStateException("Not started.");
}
if (!zkClient.isConnected()) {
throw new CloudnameException("No proper connection with zookeeper.");
}
synchronized (lastStatusVersionMonitor) {
try {
Stat stat =
zkClient
.getZookeeper()
.setData(
path,
zkCoordinateData.snapshot().serialize().getBytes(Util.CHARSET_NAME),
lastStatusVersion);
LOG.fine("Updated coordinate, latest version is " + stat.getVersion());
lastStatusVersion = stat.getVersion();
} catch (KeeperException.NoNodeException e) {
throw new CoordinateMissingException("Coordinate does not exist " + path);
} catch (KeeperException e) {
throw new CloudnameException(
"ZooKeeper errror in updateCoordinateData: " + e.getMessage(), e);
} catch (UnsupportedEncodingException e) {
throw new CloudnameException(e);
} catch (InterruptedException e) {
throw new CloudnameException(e);
} catch (IOException e) {
throw new CloudnameException(e);
}
}
}
private static boolean checkStale(SolrZkClient zkClient, String zkPath, int currentVersion) {
if (zkPath == null) return false;
try {
Stat stat = zkClient.exists(zkPath, null, true);
if (stat == null) {
if (currentVersion > -1) return true;
return false;
}
if (stat.getVersion() > currentVersion) {
log.info(
zkPath + " is stale will need an update from {} to {}",
currentVersion,
stat.getVersion());
return true;
}
return false;
} catch (KeeperException.NoNodeException nne) {
// no problem
} catch (KeeperException e) {
log.error("error refreshing solrconfig ", e);
} catch (InterruptedException e) {
Thread.currentThread().isInterrupted();
}
return false;
}
/**
* Deletes an existing unassigned node that is in the specified state for the specified region.
*
* <p>If a node does not already exist for this region, a {@link NoNodeException} will be thrown.
*
* <p>No watcher is set whether this succeeds or not.
*
* <p>Returns false if the node was not in the proper state but did exist.
*
* <p>This method is used during table disables when a region finishes successfully closing. This
* is the Master acknowledging completion of the specified regions transition to being closed.
*
* @param zkw zk reference
* @param regionName region to be deleted from zk
* @param expectedState state region must be in for delete to complete
* @param expectedVersion of the znode that is to be deleted. If expectedVersion need not be
* compared while deleting the znode pass -1
* @throws KeeperException if unexpected zookeeper exception
* @throws KeeperException.NoNodeException if node does not exist
*/
public static boolean deleteNode(
ZooKeeperWatcher zkw, String regionName, EventType expectedState, int expectedVersion)
throws KeeperException, KeeperException.NoNodeException {
LOG.debug(
zkw.prefix(
"Deleting existing unassigned "
+ "node for "
+ regionName
+ " that is in expected state "
+ expectedState));
String node = getNodeName(zkw, regionName);
zkw.sync(node);
Stat stat = new Stat();
byte[] bytes = ZKUtil.getDataNoWatch(zkw, node, stat);
if (bytes == null) {
// If it came back null, node does not exist.
throw KeeperException.create(Code.NONODE);
}
RegionTransitionData data = RegionTransitionData.fromBytes(bytes);
if (!data.getEventType().equals(expectedState)) {
LOG.warn(
zkw.prefix(
"Attempting to delete unassigned "
+ "node "
+ regionName
+ " in "
+ expectedState
+ " state but node is in "
+ data.getEventType()
+ " state"));
return false;
}
if (expectedVersion != -1 && stat.getVersion() != expectedVersion) {
LOG.warn(
"The node we are trying to delete is not the expected one. " + "Got a version mismatch");
return false;
}
synchronized (zkw.getNodes()) {
// TODO: Does this go here or only if we successfully delete node?
zkw.getNodes().remove(node);
if (!ZKUtil.deleteNode(zkw, node, stat.getVersion())) {
LOG.warn(
zkw.prefix(
"Attempting to delete "
+ "unassigned node in "
+ expectedState
+ " state but "
+ "after verifying it was in OPENED state, we got a version mismatch"));
return false;
}
LOG.debug(
zkw.prefix(
"Successfully deleted unassigned node for region "
+ regionName
+ " in expected state "
+ expectedState));
return true;
}
}
@Test
public void testSyncGet() {
String className = TestHelper.getTestClassName();
String methodName = TestHelper.getTestMethodName();
String testName = className + "_" + methodName;
System.out.println("START " + testName + " at " + new Date(System.currentTimeMillis()));
String path = String.format("/%s/%s", testName, "msg_0");
ZNRecord record = new ZNRecord("msg_0");
ZkBaseDataAccessor<ZNRecord> accessor = new ZkBaseDataAccessor<ZNRecord>(_gZkClient);
Stat stat = new Stat();
ZNRecord getRecord = accessor.get(path, stat, 0);
Assert.assertNull(getRecord);
try {
accessor.get(path, stat, AccessOption.THROW_EXCEPTION_IFNOTEXIST);
Assert.fail("Should throw exception if not exist");
} catch (Exception e) {
// OK
}
boolean success = accessor.create(path, record, AccessOption.PERSISTENT);
Assert.assertTrue(success);
getRecord = accessor.get(path, stat, 0);
Assert.assertNotNull(getRecord);
Assert.assertEquals(getRecord.getId(), "msg_0");
Assert.assertEquals(stat.getVersion(), 0);
record.setSimpleField("key0", "value0");
success = accessor.set(path, record, AccessOption.PERSISTENT);
Assert.assertTrue(success);
getRecord = accessor.get(path, stat, 0);
Assert.assertNotNull(getRecord);
Assert.assertEquals(record.getSimpleFields().size(), 1);
Assert.assertNotNull(getRecord.getSimpleField("key0"));
Assert.assertEquals(getRecord.getSimpleField("key0"), "value0");
Assert.assertEquals(stat.getVersion(), 1);
ZNRecord newRecord = new ZNRecord("msg_0");
newRecord.setSimpleField("key1", "value1");
success = accessor.update(path, new ZNRecordUpdater(newRecord), AccessOption.PERSISTENT);
Assert.assertTrue(success);
getRecord = accessor.get(path, stat, 0);
Assert.assertNotNull(getRecord);
Assert.assertEquals(getRecord.getSimpleFields().size(), 2);
Assert.assertNotNull(getRecord.getSimpleField("key0"));
Assert.assertEquals(getRecord.getSimpleField("key0"), "value0");
Assert.assertNotNull(getRecord.getSimpleField("key1"));
Assert.assertEquals(getRecord.getSimpleField("key1"), "value1");
Assert.assertEquals(stat.getVersion(), 2);
System.out.println("END " + testName + " at " + new Date(System.currentTimeMillis()));
}
/**
* Changes the shared value only if its value has not changed since this client last read it. If
* the value has changed, the value is not set and this client's view of the value is updated.
* i.e. if the value is not successful you can get the updated value by calling {@link
* #getValue()}.
*
* @param newValue the new value to attempt
* @return true if the change attempt was successful, false if not. If the change was not
* successful, {@link #getValue()} will return the updated value
* @throws Exception ZK errors, interruptions, etc.
*/
public boolean trySetValue(byte[] newValue) throws Exception {
Preconditions.checkState(state.get() == State.STARTED, "not started");
try {
client.setData().withVersion(stat.getVersion()).forPath(path, newValue);
stat.setVersion(stat.getVersion() + 1);
value = Arrays.copyOf(newValue, newValue.length);
return true;
} catch (KeeperException.BadVersionException ignore) {
// ignore
}
readValue();
return false;
}
@Test
public void testCheckVersion() throws Exception {
CuratorFramework client =
CuratorFrameworkFactory.newClient(server.getConnectString(), new RetryOneTime(1));
client.start();
try {
client.create().forPath("/foo");
Stat stat = client.setData().forPath("/foo", "new".getBytes()); // up the version
try {
client
.inTransaction()
.check()
.withVersion(stat.getVersion() + 1)
.forPath("/foo") // force a bad version
.and()
.create()
.forPath("/bar")
.and()
.commit();
Assert.fail();
} catch (KeeperException.BadVersionException correct) {
// correct
}
Assert.assertNull(client.checkExists().forPath("/bar"));
} finally {
client.close();
}
}
@Test
public void testSyncGetStat() {
String className = TestHelper.getTestClassName();
String methodName = TestHelper.getTestMethodName();
String testName = className + "_" + methodName;
System.out.println("START " + testName + " at " + new Date(System.currentTimeMillis()));
String path = String.format("/%s/%s", testName, "msg_0");
ZNRecord record = new ZNRecord("msg_0");
ZkBaseDataAccessor<ZNRecord> accessor = new ZkBaseDataAccessor<ZNRecord>(_gZkClient);
Stat stat = accessor.getStat(path, 0);
Assert.assertNull(stat);
boolean success = accessor.create(path, record, AccessOption.EPHEMERAL);
Assert.assertTrue(success);
stat = accessor.getStat(path, 0);
Assert.assertNotNull(stat);
Assert.assertEquals(stat.getVersion(), 0);
Assert.assertNotSame(stat.getEphemeralOwner(), 0);
System.out.println("END " + testName + " at " + new Date(System.currentTimeMillis()));
}
/**
* Change the shared value value irrespective of its previous state
*
* @param newValue new value
* @throws Exception ZK errors, interruptions, etc.
*/
public void setValue(byte[] newValue) throws Exception {
Preconditions.checkState(state.get() == State.STARTED, "not started");
client.setData().forPath(path, newValue);
stat.setVersion(stat.getVersion() + 1);
value = Arrays.copyOf(newValue, newValue.length);
}
public void updateRecord(MetaRecord rec) {
try {
long ts = System.currentTimeMillis();
putRecord(rec, ts);
String node = ZKUtil.joinZNode(H2MetaTableTracker.NODE_NAME, Integer.toString(rec.getId()));
// setData会异步触发所有机器(包括本机)上的H2MetaTableTracker.nodeDataChanged
// 然后触发下列调用:
// =>org.h2.engine.Database.updateDatabaseObject(int)
// =>org.h2.engine.Database.update(Session, DbObject)
// =>org.h2.engine.Database.addMeta0(Session, DbObject, boolean)
// =>又到此方法
// 所以会造成循环
synchronized (this) { // 避免setData后立刻触发nodeDataChanged，此时IdVersion还未更新
ZKUtil.setData(watcher, node, Bytes.toBytes(ts));
// setData后watch不见了，所以要继续watch，监听其他人对此node的修改
// ZKUtil.watchAndCheckExists(watcher, node);
Stat stat = new Stat();
ZKUtil.getDataAndWatch(watcher, node, stat);
// 这里记录下id的最新版本，触发nodeDataChanged时再检查一下是否版本一样，
// 如果不大于这里的版本那么就不再执行updateDatabaseObject操作
tracker.updateIdVersion(rec.getId(), stat.getVersion());
}
} catch (Exception e) {
throw new RuntimeException(e);
}
}
/**
* Try to atomically update a node in ZooKeeper, creating it if it doesn't exist. This is meant to
* be used within an optimistic concurrency model.
*
* @param pathSuffix suffix to use to build path in ZooKeeper.
* @param f function used to initialize the node, or transform the data already there.
* @return true if node was created/updated, false if a concurrent modification occurred and
* succeeded while trying to update/create the node.
* @throws Exception
*/
private boolean tryAtomicUpdate(final String pathSuffix, final NodeFunction f) throws Exception {
final String path = buildZookeeperPath(pathSuffix);
final Stat stat = zk.checkExists().forPath(path);
if (stat == null) {
try {
zk.create()
.creatingParentsIfNeeded()
.withMode(CreateMode.PERSISTENT)
.forPath(path, f.initialize());
} catch (KeeperException.NodeExistsException e) {
LOG.debug("Concurrent creation of " + path + ", retrying", e);
return false;
}
} else {
Mod<byte[]> newVal = f.apply(zk.getData().forPath(path));
if (newVal.hasModification()) {
try {
zk.setData().withVersion(stat.getVersion()).forPath(path, newVal.get());
} catch (KeeperException.BadVersionException e) {
LOG.debug("Concurrent update to " + path + ", retrying.", e);
return false;
}
}
}
return true;
}
void trigeWatcher() {
try {
Stat s = zk.exists("/root", false); // 此处不设置watcher
zk.setData("/root", "a".getBytes(), s.getVersion()); // 修改数据时需要提供version，version设为-1表示强制修改
} catch (Exception e) {
e.printStackTrace();
}
}
protected Stat setData(String path, byte[] data, Stat stat) {
try {
stat = zooKeeper.setData(path, data, stat.getVersion());
} catch (Exception e) {
System.out.println("Exception caught in zk.setData(): " + e);
}
return stat;
}
/**
* sync update
*
* @return: updatedData on success, or null on fail
*/
public T update(
String path, DataUpdater<T> updater, List<String> createPaths, Stat stat, int options) {
CreateMode mode = AccessOption.getMode(options);
if (mode == null) {
LOG.error("Invalid update mode. options: " + options);
return null;
}
boolean retry;
T updatedData = null;
do {
retry = false;
try {
Stat readStat = new Stat();
T oldData = (T) _zkClient.readData(path, readStat);
T newData = updater.update(oldData);
Stat setStat = _zkClient.writeDataGetStat(path, newData, readStat.getVersion());
if (stat != null) {
DataTree.copyStat(setStat, stat);
}
updatedData = newData;
} catch (ZkBadVersionException e) {
retry = true;
} catch (ZkNoNodeException e) {
// node not exist, try create
try {
T newData = updater.update(null);
RetCode rc = create(path, newData, createPaths, options);
switch (rc) {
case OK:
updatedData = newData;
break;
case NODE_EXISTS:
retry = true;
break;
default:
LOG.error("Fail to update path by creating: " + path);
return null;
}
} catch (Exception e1) {
LOG.error("Exception while updating path by creating: " + path, e1);
return null;
}
} catch (Exception e) {
LOG.error("Exception while updating path: " + path, e);
return null;
}
} while (retry);
return updatedData;
}
@PUT
@Path("blueprint/{name}")
public Response updateBlueprint(
@Context UriInfo uri, @PathParam("name") String oldName, ConfigManifest blueprint) {
Response res;
try {
ZooKeeper zk = Controller.getInstance().getZKInstance();
String newName = oldName;
if (blueprint.getUrl() != null) {
newName = ZookeeperUtil.getBaseURL(blueprint.getUrl().toString());
} else {
blueprint.setUrl(uri.getAbsolutePath().toURL());
}
byte[] data = JAXBUtil.write(blueprint);
Stat stat =
zk.exists(
CommonConfigurationKeys.ZOOKEEPER_CONFIG_BLUEPRINT_PATH_DEFAULT + '/' + newName,
false);
if (stat != null && oldName.equals(newName)) {
// Update existing blueprint
String path =
CommonConfigurationKeys.ZOOKEEPER_CONFIG_BLUEPRINT_PATH_DEFAULT + '/' + oldName;
zk.delete(path, stat.getVersion());
zk.create(
CommonConfigurationKeys.ZOOKEEPER_CONFIG_BLUEPRINT_PATH_DEFAULT + '/' + newName,
data,
Ids.OPEN_ACL_UNSAFE,
CreateMode.PERSISTENT);
} else if (stat != null) {
// Conflict in name change
throw new WebApplicationException(409);
} else {
// Create new blueprint
try {
zk.create(
CommonConfigurationKeys.ZOOKEEPER_CONFIG_BLUEPRINT_PATH_DEFAULT + '/' + newName,
data,
Ids.OPEN_ACL_UNSAFE,
CreateMode.PERSISTENT);
} catch (KeeperException.NodeExistsException e) {
throw new WebApplicationException(409);
}
}
res = Response.noContent().build();
return res;
} catch (WebApplicationException e) {
throw e;
} catch (Exception e) {
LOG.error(ExceptionUtil.getStackTrace(e));
throw new WebApplicationException(500);
}
}
public static 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());
}
public Integer getVersion(CuratorFramework zk, String path, boolean watch) throws Exception {
String npath = PathUtils.normalize_path(path);
Stat stat = null;
if (existsNode(zk, npath, watch)) {
if (watch) {
stat = zk.checkExists().watched().forPath(PathUtils.normalize_path(path));
} else {
stat = zk.checkExists().forPath(PathUtils.normalize_path(path));
}
return Integer.valueOf(stat.getVersion());
}
return null;
}
@DELETE
@Path("blueprint/{name}")
public Response deleteStack(@PathParam("name") String name) {
ZooKeeper zk = Controller.getInstance().getZKInstance();
try {
String path = ZookeeperUtil.getConfigManifestPath(name);
Stat current = zk.exists(path, false);
zk.delete(path, current.getVersion());
} catch (Exception e) {
LOG.error(ExceptionUtil.getStackTrace(e));
throw new WebApplicationException(500);
}
Response res = Response.noContent().build();
return res;
}
@Test(timeout = 60000)
public void testBadVersionOnTwoAllocators() throws Exception {
String allocationPath = "/allocation-bad-version";
zkc.get()
.create(allocationPath, new byte[0], ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
Stat stat = new Stat();
byte[] data = zkc.get().getData(allocationPath, false, stat);
Versioned<byte[]> allocationData =
new Versioned<byte[]>(data, new ZkVersion(stat.getVersion()));
SimpleLedgerAllocator allocator1 =
new SimpleLedgerAllocator(
allocationPath, allocationData, newQuorumConfigProvider(dlConf), zkc, bkc);
SimpleLedgerAllocator allocator2 =
new SimpleLedgerAllocator(
allocationPath, allocationData, newQuorumConfigProvider(dlConf), zkc, bkc);
allocator1.allocate();
// wait until allocated
ZKTransaction txn1 = newTxn();
LedgerHandle lh = FutureUtils.result(allocator1.tryObtain(txn1, NULL_LISTENER));
allocator2.allocate();
ZKTransaction txn2 = newTxn();
try {
FutureUtils.result(allocator2.tryObtain(txn2, NULL_LISTENER));
fail(
"Should fail allocating on second allocator as allocator1 is starting allocating something.");
} catch (ZKException zke) {
assertEquals(KeeperException.Code.BADVERSION, zke.getKeeperExceptionCode());
}
FutureUtils.result(txn1.execute());
Utils.close(allocator1);
Utils.close(allocator2);
long eid = lh.addEntry("hello world".getBytes());
lh.close();
LedgerHandle readLh =
bkc.get()
.openLedger(lh.getId(), BookKeeper.DigestType.CRC32, dlConf.getBKDigestPW().getBytes());
Enumeration<LedgerEntry> entries = readLh.readEntries(eid, eid);
int i = 0;
while (entries.hasMoreElements()) {
LedgerEntry entry = entries.nextElement();
assertEquals("hello world", new String(entry.getEntry(), UTF_8));
++i;
}
assertEquals(1, i);
}
/**
* Atomically sets the value to the given updated value if the current value {@code ==} the
* expected value. Remember to always check {@link AtomicValue#succeeded()}.
*
* @param expectedValue the expected value
* @param newValue the new value
* @return value info
* @throws Exception ZooKeeper errors
*/
public AtomicValue<byte[]> compareAndSet(byte[] expectedValue, byte[] newValue) throws Exception {
Stat stat = new Stat();
MutableAtomicValue<byte[]> result = new MutableAtomicValue<byte[]>(null, null, false);
boolean createIt = getCurrentValue(result, stat);
if (!createIt && Arrays.equals(expectedValue, result.preValue)) {
try {
client.setData().withVersion(stat.getVersion()).forPath(path, newValue);
result.succeeded = true;
result.postValue = newValue;
} catch (KeeperException.BadVersionException dummy) {
result.succeeded = false;
} catch (KeeperException.NoNodeException dummy) {
result.succeeded = false;
}
} else {
result.succeeded = false;
}
return result;
}
/**
* Try to own the task by transitioning the zk node data from UNASSIGNED to OWNED.
*
* <p>This method is also used to periodically heartbeat the task progress by transitioning the
* node from OWNED to OWNED.
*
* <p>
*
* @param isFirstTime shows whther it's the first attempt.
* @param zkw zk wathcer
* @param server name
* @param task to own
* @param taskZKVersion version of the task in zk
* @return non-negative integer value when task can be owned by current region server otherwise -1
*/
protected static int attemptToOwnTask(
boolean isFirstTime,
ZooKeeperWatcher zkw,
ServerName server,
String task,
RecoveryMode mode,
int taskZKVersion) {
int latestZKVersion = FAILED_TO_OWN_TASK;
try {
SplitLogTask slt = new SplitLogTask.Owned(server, mode);
Stat stat = zkw.getRecoverableZooKeeper().setData(task, slt.toByteArray(), taskZKVersion);
if (stat == null) {
LOG.warn("zk.setData() returned null for path " + task);
SplitLogCounters.tot_wkr_task_heartbeat_failed.incrementAndGet();
return FAILED_TO_OWN_TASK;
}
latestZKVersion = stat.getVersion();
SplitLogCounters.tot_wkr_task_heartbeat.incrementAndGet();
return latestZKVersion;
} catch (KeeperException e) {
if (!isFirstTime) {
if (e.code().equals(KeeperException.Code.NONODE)) {
LOG.warn("NONODE failed to assert ownership for " + task, e);
} else if (e.code().equals(KeeperException.Code.BADVERSION)) {
LOG.warn("BADVERSION failed to assert ownership for " + task, e);
} else {
LOG.warn("failed to assert ownership for " + task, e);
}
}
} catch (InterruptedException e1) {
LOG.warn(
"Interrupted while trying to assert ownership of "
+ task
+ " "
+ StringUtils.stringifyException(e1));
Thread.currentThread().interrupt();
}
SplitLogCounters.tot_wkr_task_heartbeat_failed.incrementAndGet();
return FAILED_TO_OWN_TASK;
}
public void write(String path, String value) throws InterruptedException, KeeperException {
int retries = 0;
while (true) {
try {
Stat stat = zk.exists(path, false);
if (stat == null) {
zk.create(path, value.getBytes(CHARSET), Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
} else {
zk.setData(path, value.getBytes(CHARSET), stat.getVersion());
}
return;
} catch (KeeperException.SessionExpiredException e) {
throw e;
} catch (KeeperException e) {
if (retries++ == MAX_RETRIES) {
throw e;
}
// sleep then retry
TimeUnit.SECONDS.sleep(RETRY_PERIOD_SECONDS);
}
}
}
/** @see org.storevm.toolkits.session.zookeeper.handler.GetDataHandler#handle() */
@SuppressWarnings("unchecked")
@Override
public <T> T handle() throws Exception {
if (zookeeper != null) {
String path = GROUP_NAME + NODE_SEP + id;
// 检查指定的Session节点是否存在
Stat stat = zookeeper.exists(path, false);
// 如果节点存在则删除之
if (stat != null) {
// 查找数据节点是否存在，不存在就创建一个
String dataPath = path + NODE_SEP + key;
stat = zookeeper.exists(dataPath, false);
if (stat == null) {
// 创建数据节点
zookeeper.create(dataPath, null, Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
if (LOGGER.isInfoEnabled()) {
LOGGER.info("创建数据节点完成[" + dataPath + "]");
}
}
// 在节点上设置数据，所有数据必须可序列化
if (data instanceof Serializable) {
int dataNodeVer = -1;
if (stat != null) {
// 记录数据节点的版本
dataNodeVer = stat.getVersion();
}
byte[] arrData = SerializationUtils.serialize(data);
stat = zookeeper.setData(dataPath, arrData, dataNodeVer);
if (LOGGER.isInfoEnabled()) {
LOGGER.info("更新数据节点数据完成[" + dataPath + "][" + data + "]");
}
return (T) Boolean.TRUE;
}
}
}
return (T) Boolean.FALSE;
}
private boolean tryOnce(MutableAtomicValue<byte[]> result, MakeValue makeValue) throws Exception {
Stat stat = new Stat();
boolean createIt = getCurrentValue(result, stat);
boolean success = false;
try {
byte[] newValue = makeValue.makeFrom(result.preValue);
if (createIt) {
client.create().forPath(path, newValue);
} else {
client.setData().withVersion(stat.getVersion()).forPath(path, newValue);
}
result.postValue = Arrays.copyOf(newValue, newValue.length);
success = true;
} catch (KeeperException.NodeExistsException e) {
// do Retry
} catch (KeeperException.BadVersionException e) {
// do Retry
} catch (KeeperException.NoNodeException e) {
// do Retry
}
return success;
}
public void consume() {
while (true) {
if (zooKeeper != null) {
synchronized (mutex) {
try {
List<String> children = zooKeeper.getChildren(root, true);
if (children.size() == 0) {
mutex.wait();
} else {
Stat stat = new Stat();
String minElement = root + "/" + min(children);
String value = new String(zooKeeper.getData(minElement, false, stat));
System.out.println(value);
zooKeeper.delete(minElement, stat.getVersion());
}
} catch (KeeperException | InterruptedException e) {
e.printStackTrace();
}
}
}
}
}
@Test
public void testBasicFunctionality() throws Exception {
// Check ZNode for timestamp exists (storage instantiation should create it)
Stat zNodeStats = zkClient.checkExists().forPath(TIMESTAMP_ZNODE);
assertEquals(zNodeStats.getVersion(), 0);
// Initial checks
assertEquals(storage.getMaxTimestamp(), INITIAL_MAX_TS_VALUE);
byte[] data = zkClient.getData().forPath(TIMESTAMP_ZNODE);
assertEquals(data.length, BYTES_IN_LONG);
// Check new timestamp does not allow negative values...
try {
storage.updateMaxTimestamp(INITIAL_MAX_TS_VALUE, NEGATIVE_TS);
fail();
} catch (IllegalArgumentException e) {
LOG.info("Expected exception", e);
}
// ...nor is less than previous timestamp
try {
storage.updateMaxTimestamp(1, 0);
fail();
} catch (IllegalArgumentException e) {
LOG.info("Expected exception", e);
}
// Check that the original version is still there
zNodeStats = zkClient.checkExists().forPath(TIMESTAMP_ZNODE);
assertEquals(zNodeStats.getVersion(), 0);
// Iterate updating the timestamp and check the final value
long previousMaxTimestamp = INITIAL_MAX_TS_VALUE;
for (int i = 0; i < ITERATION_COUNT; i++) {
long newMaxTimestamp = previousMaxTimestamp + 1_000_000;
storage.updateMaxTimestamp(previousMaxTimestamp, newMaxTimestamp);
previousMaxTimestamp = newMaxTimestamp;
}
assertEquals(storage.getMaxTimestamp(), 1_000_000 * ITERATION_COUNT);
// Check the znode version has changed accordingly
zNodeStats = zkClient.checkExists().forPath(TIMESTAMP_ZNODE);
assertEquals(zNodeStats.getVersion(), ITERATION_COUNT);
// Check exceptions
doThrow(new RuntimeException()).when(storageInternalZKClient).getData();
try {
storage.getMaxTimestamp();
fail();
} catch (IOException e) {
LOG.info("Expected exception", e);
}
doThrow(new RuntimeException()).when(storageInternalZKClient).setData();
try {
storage.updateMaxTimestamp(INITIAL_MAX_TS_VALUE, INITIAL_MAX_TS_VALUE + 1_000_000);
fail();
} catch (IOException e) {
LOG.info("Expected exception", e);
}
// Reset the mock and double-check last result
Mockito.reset(storageInternalZKClient);
assertEquals(storage.getMaxTimestamp(), 1_000_000 * ITERATION_COUNT);
// Finally check the znode version is still the same
zNodeStats = zkClient.checkExists().forPath(TIMESTAMP_ZNODE);
assertEquals(zNodeStats.getVersion(), ITERATION_COUNT);
}
@Test
public void testShouldNotCompeleteOpenedEntityGroupSuccessfullyIfVersionMismatches()
throws Exception {
EntityGroup entityGroup = null;
try {
int testIndex = 0;
TEST_UTIL.getHBaseTestingUtility().startMiniZKCluster();
TEST_UTIL
.getConfiguration()
.set(
FConstants.ZOOKEEPER_QUORUM,
TEST_UTIL.getConfiguration().get(HConstants.ZOOKEEPER_QUORUM));
TEST_UTIL
.getConfiguration()
.set(
FConstants.ZOOKEEPER_CLIENT_PORT,
TEST_UTIL.getConfiguration().get(HConstants.ZOOKEEPER_CLIENT_PORT));
final Server server = new MockServer(TEST_UTIL);
FTable htd =
FMetaTestUtil.makeTable(
"testShouldNotCompeleteOpenedEntityGroupSuccessfullyIfVersionMismatches");
EntityGroupInfo egi =
new EntityGroupInfo(
Bytes.toBytes(htd.getTableName()),
Bytes.toBytes(testIndex),
Bytes.toBytes(testIndex + 1));
entityGroup = EntityGroup.createEntityGroup(egi, TEST_UTIL.getConfiguration(), htd, null);
assertNotNull(entityGroup);
AssignmentManager am = Mockito.mock(AssignmentManager.class);
EntityGroupStates rsm = Mockito.mock(EntityGroupStates.class);
Mockito.doReturn(rsm).when(am).getEntityGroupStates();
when(rsm.isEntityGroupInTransition(egi)).thenReturn(false);
when(rsm.getEntityGroupState(egi))
.thenReturn(
new EntityGroupState(
entityGroup.getEntityGroupInfo(),
EntityGroupState.State.OPEN,
System.currentTimeMillis(),
server.getServerName()));
// create a node with OPENED state
zkw =
WaspTestingUtility.createAndForceNodeToOpenedState(
TEST_UTIL, entityGroup, server.getServerName());
when(am.getZKTable()).thenReturn(new ZKTable(zkw));
Stat stat = new Stat();
String nodeName =
ZKAssign.getNodeName(zkw, entityGroup.getEntityGroupInfo().getEncodedName());
ZKUtil.getDataAndWatch(zkw, nodeName, stat);
// use the version for the OpenedEntityGroupHandler
OpenedEntityGroupHandler handler =
new OpenedEntityGroupHandler(
server,
am,
entityGroup.getEntityGroupInfo(),
server.getServerName(),
stat.getVersion());
// Once again overwrite the same znode so that the version changes.
ZKAssign.transitionNode(
zkw,
entityGroup.getEntityGroupInfo(),
server.getServerName(),
EventType.FSERVER_ZK_ENTITYGROUP_OPENED,
EventType.FSERVER_ZK_ENTITYGROUP_OPENED,
stat.getVersion());
// Should not invoke assignmentmanager.entityGroupOnline. If it is
// invoked as per current mocking it will throw null pointer exception.
boolean expectedException = false;
try {
handler.process();
} catch (Exception e) {
expectedException = true;
}
assertFalse("The process method should not throw any exception.", expectedException);
List<String> znodes = ZKUtil.listChildrenAndWatchForNewChildren(zkw, zkw.assignmentZNode);
String entityGroupName = znodes.get(0);
assertEquals(
"The entityGroup should not be opened successfully.",
entityGroupName,
entityGroup.getEntityGroupInfo().getEncodedName());
} finally {
EntityGroup.closeEntityGroup(entityGroup);
TEST_UTIL.getHBaseTestingUtility().shutdownMiniZKCluster();
}
}
/**
* try to grab a 'lock' on the task zk node to own and execute the task.
*
* <p>
*
* @param path zk node for the task
*/
private void grabTask(String path) {
Stat stat = new Stat();
byte[] data;
synchronized (grabTaskLock) {
currentTask = path;
workerInGrabTask = true;
if (Thread.interrupted()) {
return;
}
}
try {
try {
if ((data = ZKUtil.getDataNoWatch(watcher, path, stat)) == null) {
SplitLogCounters.tot_wkr_failed_to_grab_task_no_data.incrementAndGet();
return;
}
} catch (KeeperException e) {
LOG.warn("Failed to get data for znode " + path, e);
SplitLogCounters.tot_wkr_failed_to_grab_task_exception.incrementAndGet();
return;
}
SplitLogTask slt;
try {
slt = SplitLogTask.parseFrom(data);
} catch (DeserializationException e) {
LOG.warn("Failed parse data for znode " + path, e);
SplitLogCounters.tot_wkr_failed_to_grab_task_exception.incrementAndGet();
return;
}
if (!slt.isUnassigned()) {
SplitLogCounters.tot_wkr_failed_to_grab_task_owned.incrementAndGet();
return;
}
currentVersion =
attemptToOwnTask(
true, watcher, server.getServerName(), path, slt.getMode(), stat.getVersion());
if (currentVersion < 0) {
SplitLogCounters.tot_wkr_failed_to_grab_task_lost_race.incrementAndGet();
return;
}
if (ZKSplitLog.isRescanNode(watcher, currentTask)) {
ZkSplitLogWorkerCoordination.ZkSplitTaskDetails splitTaskDetails =
new ZkSplitLogWorkerCoordination.ZkSplitTaskDetails();
splitTaskDetails.setTaskNode(currentTask);
splitTaskDetails.setCurTaskZKVersion(new MutableInt(currentVersion));
endTask(
new SplitLogTask.Done(server.getServerName(), slt.getMode()),
SplitLogCounters.tot_wkr_task_acquired_rescan,
splitTaskDetails);
return;
}
LOG.info("worker " + server.getServerName() + " acquired task " + path);
SplitLogCounters.tot_wkr_task_acquired.incrementAndGet();
getDataSetWatchAsync();
submitTask(path, slt.getMode(), currentVersion, reportPeriod);
// after a successful submit, sleep a little bit to allow other RSs to grab the rest tasks
try {
int sleepTime = RandomUtils.nextInt(500) + 500;
Thread.sleep(sleepTime);
} catch (InterruptedException e) {
LOG.warn("Interrupted while yielding for other region servers", e);
Thread.currentThread().interrupt();
}
} finally {
synchronized (grabTaskLock) {
workerInGrabTask = false;
// clear the interrupt from stopTask() otherwise the next task will
// suffer
Thread.interrupted();
}
}
}
/**
* Private method that actually performs unassigned node transitions.
*
* <p>Attempts to transition the unassigned node for the specified region from the expected state
* to the state in the specified transition data.
*
* <p>Method first reads existing data and verifies it is in the expected state. If the node does
* not exist or the node is not in the expected state, the method returns -1. If the transition is
* successful, the version number of the node following the transition is returned.
*
* <p>If the read state is what is expected, it attempts to write the new state and data into the
* node. When doing this, it includes the expected version (determined when the existing state was
* verified) to ensure that only one transition is successful. If there is a version mismatch, the
* method returns -1.
*
* <p>If the write is successful, no watch is set and the method returns true.
*
* @param zkw zk reference
* @param region region to be transitioned to opened
* @param serverName server event originates from
* @param endState state to transition node to if all checks pass
* @param beginState state the node must currently be in to do transition
* @param expectedVersion expected version of data before modification, or -1
* @return version of node after transition, -1 if unsuccessful transition
* @throws KeeperException if unexpected zookeeper exception
*/
public static int transitionNode(
ZooKeeperWatcher zkw,
HRegionInfo region,
String serverName,
EventType beginState,
EventType endState,
int expectedVersion)
throws KeeperException {
String encoded = region.getEncodedName();
if (LOG.isDebugEnabled()) {
LOG.debug(
zkw.prefix(
"Attempting to transition node "
+ HRegionInfo.prettyPrint(encoded)
+ " from "
+ beginState.toString()
+ " to "
+ endState.toString()));
}
String node = getNodeName(zkw, encoded);
zkw.sync(node);
// Read existing data of the node
Stat stat = new Stat();
byte[] existingBytes = ZKUtil.getDataNoWatch(zkw, node, stat);
if (existingBytes == null) {
// Node no longer exists. Return -1. It means unsuccessful transition.
return -1;
}
RegionTransitionData existingData = RegionTransitionData.fromBytes(existingBytes);
// Verify it is the expected version
if (expectedVersion != -1 && stat.getVersion() != expectedVersion) {
LOG.warn(
zkw.prefix(
"Attempt to transition the "
+ "unassigned node for "
+ encoded
+ " from "
+ beginState
+ " to "
+ endState
+ " failed, "
+ "the node existed but was version "
+ stat.getVersion()
+ " not the expected version "
+ expectedVersion));
return -1;
}
// Verify it is in expected state
if (!existingData.getEventType().equals(beginState)) {
LOG.warn(
zkw.prefix(
"Attempt to transition the "
+ "unassigned node for "
+ encoded
+ " from "
+ beginState
+ " to "
+ endState
+ " failed, "
+ "the node existed but was in the state "
+ existingData.getEventType()
+ " set by the server "
+ existingData.getServerName()));
return -1;
}
// Write new data, ensuring data has not changed since we last read it
try {
RegionTransitionData data =
new RegionTransitionData(endState, region.getRegionName(), serverName);
if (!ZKUtil.setData(zkw, node, data.getBytes(), stat.getVersion())) {
LOG.warn(
zkw.prefix(
"Attempt to transition the "
+ "unassigned node for "
+ encoded
+ " from "
+ beginState
+ " to "
+ endState
+ " failed, "
+ "the node existed and was in the expected state but then when "
+ "setting data we got a version mismatch"));
return -1;
}
if (LOG.isDebugEnabled()) {
LOG.debug(
zkw.prefix(
"Successfully transitioned node "
+ encoded
+ " from "
+ beginState
+ " to "
+ endState));
}
return stat.getVersion() + 1;
} catch (KeeperException.NoNodeException nne) {
LOG.warn(
zkw.prefix(
"Attempt to transition the "
+ "unassigned node for "
+ encoded
+ " from "
+ beginState
+ " to "
+ endState
+ " failed, "
+ "the node existed and was in the expected state but then when "
+ "setting data it no longer existed"));
return -1;
}
}
/**
* Allows you to do
*
* <pre><code>node.data = "some data: ${var}"</code></pre>
*
* in Groovy code.
*
* @param data
* @throws InterruptedException
* @throws KeeperException
*/
public void setData(Object data) throws InterruptedException, KeeperException {
zookeeper.setData(path, serialize(data), stat.getVersion());
}
@Test(timeout = 60000)
public void testSuccessAllocatorShouldDeleteUnusedledger() throws Exception {
String allocationPath = "/allocation-delete-unused-ledger";
zkc.get()
.create(allocationPath, new byte[0], ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT);
Stat stat = new Stat();
byte[] data = zkc.get().getData(allocationPath, false, stat);
Versioned<byte[]> allocationData =
new Versioned<byte[]>(data, new ZkVersion(stat.getVersion()));
SimpleLedgerAllocator allocator1 =
new SimpleLedgerAllocator(
allocationPath, allocationData, newQuorumConfigProvider(dlConf), zkc, bkc);
allocator1.allocate();
// wait until allocated
ZKTransaction txn1 = newTxn();
LedgerHandle lh1 = FutureUtils.result(allocator1.tryObtain(txn1, NULL_LISTENER));
// Second allocator kicks in
stat = new Stat();
data = zkc.get().getData(allocationPath, false, stat);
allocationData = new Versioned<byte[]>(data, new ZkVersion(stat.getVersion()));
SimpleLedgerAllocator allocator2 =
new SimpleLedgerAllocator(
allocationPath, allocationData, newQuorumConfigProvider(dlConf), zkc, bkc);
allocator2.allocate();
// wait until allocated
ZKTransaction txn2 = newTxn();
LedgerHandle lh2 = FutureUtils.result(allocator2.tryObtain(txn2, NULL_LISTENER));
// should fail to commit txn1 as version is changed by second allocator
try {
FutureUtils.result(txn1.execute());
fail(
"Should fail commit obtaining ledger handle from first allocator as allocator is modified by second allocator.");
} catch (ZKException ke) {
// as expected
}
FutureUtils.result(txn2.execute());
Utils.close(allocator1);
Utils.close(allocator2);
// ledger handle should be deleted
try {
lh1.close();
fail("LedgerHandle allocated by allocator1 should be deleted.");
} catch (BKException bke) {
// as expected
}
try {
bkc.get()
.openLedger(lh1.getId(), BookKeeper.DigestType.CRC32, dlConf.getBKDigestPW().getBytes());
fail("LedgerHandle allocated by allocator1 should be deleted.");
} catch (BKException.BKNoSuchLedgerExistsException nslee) {
// as expected
}
long eid = lh2.addEntry("hello world".getBytes());
lh2.close();
LedgerHandle readLh =
bkc.get()
.openLedger(
lh2.getId(), BookKeeper.DigestType.CRC32, dlConf.getBKDigestPW().getBytes());
Enumeration<LedgerEntry> entries = readLh.readEntries(eid, eid);
int i = 0;
while (entries.hasMoreElements()) {
LedgerEntry entry = entries.nextElement();
assertEquals("hello world", new String(entry.getEntry(), UTF_8));
++i;
}
assertEquals(1, i);
}