/**
* 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.hadoop.hbase.wal;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.regex.Pattern;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hbase.HConstants;
import org.apache.hadoop.hbase.ServerName;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.hbase.classification.InterfaceStability;
import org.apache.hadoop.hbase.regionserver.wal.AbstractFSWAL;
import org.apache.hadoop.hbase.regionserver.wal.WALActionsListener;
import org.apache.hadoop.hbase.util.CancelableProgressable;
import org.apache.hadoop.hbase.util.FSUtils;
import org.apache.hadoop.hbase.util.LeaseNotRecoveredException;
import com.google.common.annotations.VisibleForTesting;
/**
* Base class of a WAL Provider that returns a single thread safe WAL that writes to Hadoop FS. By
* default, this implementation picks a directory in Hadoop FS based on a combination of
* <ul>
* <li>the HBase root directory
* <li>HConstants.HREGION_LOGDIR_NAME
* <li>the given factory's factoryId (usually identifying the regionserver by host:port)
* </ul>
* It also uses the providerId to differentiate among files.
*/
@InterfaceAudience.Private
@InterfaceStability.Evolving
public abstract class AbstractFSWALProvider<T extends AbstractFSWAL<?>> implements WALProvider {
private static final Log LOG = LogFactory.getLog(AbstractFSWALProvider.class);
// Only public so classes back in regionserver.wal can access
public interface Reader extends WAL.Reader {
/**
* @param fs File system.
* @param path Path.
* @param c Configuration.
* @param s Input stream that may have been pre-opened by the caller; may be null.
*/
void init(FileSystem fs, Path path, Configuration c, FSDataInputStream s) throws IOException;
}
protected volatile T wal;
protected WALFactory factory = null;
protected Configuration conf = null;
protected List<WALActionsListener> listeners = null;
protected String providerId = null;
protected AtomicBoolean initialized = new AtomicBoolean(false);
// for default wal provider, logPrefix won't change
protected String logPrefix = null;
/**
* we synchronized on walCreateLock to prevent wal recreation in different threads
*/
private final Object walCreateLock = new Object();
/**
* @param factory factory that made us, identity used for FS layout. may not be null
* @param conf may not be null
* @param listeners may be null
* @param providerId differentiate between providers from one factory, used for FS layout. may be
* null
*/
@Override
public void init(WALFactory factory, Configuration conf, List<WALActionsListener> listeners,
String providerId) throws IOException {
if (!initialized.compareAndSet(false, true)) {
throw new IllegalStateException("WALProvider.init should only be called once.");
}
this.factory = factory;
this.conf = conf;
this.listeners = listeners;
this.providerId = providerId;
// get log prefix
StringBuilder sb = new StringBuilder().append(factory.factoryId);
if (providerId != null) {
if (providerId.startsWith(WAL_FILE_NAME_DELIMITER)) {
sb.append(providerId);
} else {
sb.append(WAL_FILE_NAME_DELIMITER).append(providerId);
}
}
logPrefix = sb.toString();
doInit(conf);
}
@Override
public List<WAL> getWALs() throws IOException {
if (wal == null) {
return Collections.emptyList();
}
List<WAL> wals = new ArrayList<>(1);
wals.add(wal);
return wals;
}
@Override
public T getWAL(byte[] identifier, byte[] namespace) throws IOException {
T walCopy = wal;
if (walCopy == null) {
// only lock when need to create wal, and need to lock since
// creating hlog on fs is time consuming
synchronized (walCreateLock) {
walCopy = wal;
if (walCopy == null) {
walCopy = createWAL();
wal = walCopy;
}
}
}
return walCopy;
}
protected abstract T createWAL() throws IOException;
protected abstract void doInit(Configuration conf) throws IOException;
@Override
public void shutdown() throws IOException {
T log = this.wal;
if (log != null) {
log.shutdown();
}
}
@Override
public void close() throws IOException {
T log = this.wal;
if (log != null) {
log.close();
}
}
/**
* iff the given WALFactory is using the DefaultWALProvider for meta and/or non-meta, count the
* number of files (rolled and active). if either of them aren't, count 0 for that provider.
*/
@Override
public long getNumLogFiles() {
T log = this.wal;
return log == null ? 0 : log.getNumLogFiles();
}
/**
* iff the given WALFactory is using the DefaultWALProvider for meta and/or non-meta, count the
* size of files (only rolled). if either of them aren't, count 0 for that provider.
*/
@Override
public long getLogFileSize() {
T log = this.wal;
return log == null ? 0 : log.getLogFileSize();
}
/**
* returns the number of rolled WAL files.
*/
@VisibleForTesting
public static int getNumRolledLogFiles(WAL wal) {
return ((AbstractFSWAL<?>) wal).getNumRolledLogFiles();
}
/**
* returns the size of rolled WAL files.
*/
@VisibleForTesting
public static long getLogFileSize(WAL wal) {
return ((AbstractFSWAL<?>) wal).getLogFileSize();
}
/**
* return the current filename from the current wal.
*/
@VisibleForTesting
public static Path getCurrentFileName(final WAL wal) {
return ((AbstractFSWAL<?>) wal).getCurrentFileName();
}
/**
* request a log roll, but don't actually do it.
*/
@VisibleForTesting
static void requestLogRoll(final WAL wal) {
((AbstractFSWAL<?>) wal).requestLogRoll();
}
// should be package private; more visible for use in AbstractFSWAL
public static final String WAL_FILE_NAME_DELIMITER = ".";
/** The hbase:meta region's WAL filename extension */
@VisibleForTesting
public static final String META_WAL_PROVIDER_ID = ".meta";
static final String DEFAULT_PROVIDER_ID = "default";
// Implementation details that currently leak in tests or elsewhere follow
/** File Extension used while splitting an WAL into regions (HBASE-2312) */
public static final String SPLITTING_EXT = "-splitting";
/**
* It returns the file create timestamp from the file name. For name format see
* {@link #validateWALFilename(String)} public until remaining tests move to o.a.h.h.wal
* @param wal must not be null
* @return the file number that is part of the WAL file name
*/
@VisibleForTesting
public static long extractFileNumFromWAL(final WAL wal) {
final Path walName = ((AbstractFSWAL<?>) wal).getCurrentFileName();
if (walName == null) {
throw new IllegalArgumentException("The WAL path couldn't be null");
}
final String[] walPathStrs = walName.toString().split("\\" + WAL_FILE_NAME_DELIMITER);
return Long.parseLong(walPathStrs[walPathStrs.length - (isMetaFile(walName) ? 2 : 1)]);
}
/**
* Pattern used to validate a WAL file name see {@link #validateWALFilename(String)} for
* description.
*/
private static final Pattern pattern = Pattern
.compile(".*\\.\\d*(" + META_WAL_PROVIDER_ID + ")*");
/**
* A WAL file name is of the format: <wal-name>{@link #WAL_FILE_NAME_DELIMITER}
* <file-creation-timestamp>[.meta]. provider-name is usually made up of a server-name and a
* provider-id
* @param filename name of the file to validate
* @return <tt>true</tt> if the filename matches an WAL, <tt>false</tt> otherwise
*/
public static boolean validateWALFilename(String filename) {
return pattern.matcher(filename).matches();
}
/**
* Construct the directory name for all WALs on a given server. Dir names currently look like
* this for WALs: <code>hbase//WALs/kalashnikov.att.net,61634,1486865297088</code>.
* @param serverName Server name formatted as described in {@link ServerName}
* @return the relative WAL directory name, e.g. <code>.logs/1.example.org,60030,12345</code> if
* <code>serverName</code> passed is <code>1.example.org,60030,12345</code>
*/
public static String getWALDirectoryName(final String serverName) {
StringBuilder dirName = new StringBuilder(HConstants.HREGION_LOGDIR_NAME);
dirName.append("/");
dirName.append(serverName);
return dirName.toString();
}
/**
* Pulls a ServerName out of a Path generated according to our layout rules. In the below layouts,
* this method ignores the format of the logfile component. Current format: [base directory for
* hbase]/hbase/.logs/ServerName/logfile or [base directory for
* hbase]/hbase/.logs/ServerName-splitting/logfile Expected to work for individual log files and
* server-specific directories.
* @return null if it's not a log file. Returns the ServerName of the region server that created
* this log file otherwise.
*/
public static ServerName getServerNameFromWALDirectoryName(Configuration conf, String path)
throws IOException {
if (path == null || path.length() <= HConstants.HREGION_LOGDIR_NAME.length()) {
return null;
}
if (conf == null) {
throw new IllegalArgumentException("parameter conf must be set");
}
final String rootDir = conf.get(HConstants.HBASE_DIR);
if (rootDir == null || rootDir.isEmpty()) {
throw new IllegalArgumentException(HConstants.HBASE_DIR + " key not found in conf.");
}
final StringBuilder startPathSB = new StringBuilder(rootDir);
if (!rootDir.endsWith("/")) {
startPathSB.append('/');
}
startPathSB.append(HConstants.HREGION_LOGDIR_NAME);
if (!HConstants.HREGION_LOGDIR_NAME.endsWith("/")) {
startPathSB.append('/');
}
final String startPath = startPathSB.toString();
String fullPath;
try {
fullPath = FileSystem.get(conf).makeQualified(new Path(path)).toString();
} catch (IllegalArgumentException e) {
LOG.info("Call to makeQualified failed on " + path + " " + e.getMessage());
return null;
}
if (!fullPath.startsWith(startPath)) {
return null;
}
final String serverNameAndFile = fullPath.substring(startPath.length());
if (serverNameAndFile.indexOf('/') < "a,0,0".length()) {
// Either it's a file (not a directory) or it's not a ServerName format
return null;
}
Path p = new Path(path);
return getServerNameFromWALDirectoryName(p);
}
/**
* This function returns region server name from a log file name which is in one of the following
* formats:
* <ul>
* <li>hdfs://<name node>/hbase/.logs/<server name>-splitting/...</li>
* <li>hdfs://<name node>/hbase/.logs/<server name>/...</li>
* </ul>
* @return null if the passed in logFile isn't a valid WAL file path
*/
public static ServerName getServerNameFromWALDirectoryName(Path logFile) {
String logDirName = logFile.getParent().getName();
// We were passed the directory and not a file in it.
if (logDirName.equals(HConstants.HREGION_LOGDIR_NAME)) {
logDirName = logFile.getName();
}
ServerName serverName = null;
if (logDirName.endsWith(SPLITTING_EXT)) {
logDirName = logDirName.substring(0, logDirName.length() - SPLITTING_EXT.length());
}
try {
serverName = ServerName.parseServerName(logDirName);
} catch (IllegalArgumentException|IllegalStateException ex) {
serverName = null;
LOG.warn("Cannot parse a server name from path=" + logFile + "; " + ex.getMessage());
}
if (serverName != null && serverName.getStartcode() < 0) {
LOG.warn("Invalid log file path=" + logFile);
serverName = null;
}
return serverName;
}
public static boolean isMetaFile(Path p) {
return isMetaFile(p.getName());
}
public static boolean isMetaFile(String p) {
if (p != null && p.endsWith(META_WAL_PROVIDER_ID)) {
return true;
}
return false;
}
public static boolean isArchivedLogFile(Path p) {
String oldLog = Path.SEPARATOR + HConstants.HREGION_OLDLOGDIR_NAME + Path.SEPARATOR;
return p.toString().contains(oldLog);
}
/**
* Get the archived WAL file path
* @param path - active WAL file path
* @param conf - configuration
* @return archived path if exists, path - otherwise
* @throws IOException exception
*/
public static Path getArchivedLogPath(Path path, Configuration conf) throws IOException {
Path rootDir = FSUtils.getRootDir(conf);
Path oldLogDir = new Path(rootDir, HConstants.HREGION_OLDLOGDIR_NAME);
Path archivedLogLocation = new Path(oldLogDir, path.getName());
final FileSystem fs = FSUtils.getCurrentFileSystem(conf);
if (fs.exists(archivedLogLocation)) {
LOG.info("Log " + path + " was moved to " + archivedLogLocation);
return archivedLogLocation;
} else {
LOG.error("Couldn't locate log: " + path);
return path;
}
}
/**
* Opens WAL reader with retries and
* additional exception handling
* @param path path to WAL file
* @param conf configuration
* @return WAL Reader instance
* @throws IOException
*/
public static org.apache.hadoop.hbase.wal.WAL.Reader
openReader(Path path, Configuration conf)
throws IOException
{
long retryInterval = 2000; // 2 sec
int maxAttempts = 30;
int attempt = 0;
Exception ee = null;
org.apache.hadoop.hbase.wal.WAL.Reader reader = null;
while (reader == null && attempt++ < maxAttempts) {
try {
// Detect if this is a new file, if so get a new reader else
// reset the current reader so that we see the new data
reader = WALFactory.createReader(path.getFileSystem(conf), path, conf);
return reader;
} catch (FileNotFoundException fnfe) {
// If the log was archived, continue reading from there
Path archivedLog = AbstractFSWALProvider.getArchivedLogPath(path, conf);
if (path != archivedLog) {
return openReader(archivedLog, conf);
} else {
throw fnfe;
}
} catch (LeaseNotRecoveredException lnre) {
// HBASE-15019 the WAL was not closed due to some hiccup.
LOG.warn("Try to recover the WAL lease " + path, lnre);
recoverLease(conf, path);
reader = null;
ee = lnre;
} catch (NullPointerException npe) {
// Workaround for race condition in HDFS-4380
// which throws a NPE if we open a file before any data node has the most recent block
// Just sleep and retry. Will require re-reading compressed WALs for compressionContext.
LOG.warn("Got NPE opening reader, will retry.");
reader = null;
ee = npe;
}
if (reader == null) {
// sleep before next attempt
try {
Thread.sleep(retryInterval);
} catch (InterruptedException e) {
}
}
}
throw new IOException("Could not open reader", ee);
}
// For HBASE-15019
private static void recoverLease(final Configuration conf, final Path path) {
try {
final FileSystem dfs = FSUtils.getCurrentFileSystem(conf);
FSUtils fsUtils = FSUtils.getInstance(dfs, conf);
fsUtils.recoverFileLease(dfs, path, conf, new CancelableProgressable() {
@Override
public boolean progress() {
LOG.debug("Still trying to recover WAL lease: " + path);
return true;
}
});
} catch (IOException e) {
LOG.warn("unable to recover lease for WAL: " + path, e);
}
}
/**
* Get prefix of the log from its name, assuming WAL name in format of
* log_prefix.filenumber.log_suffix
* @param name Name of the WAL to parse
* @return prefix of the log
* @see AbstractFSWAL#getCurrentFileName()
*/
public static String getWALPrefixFromWALName(String name) {
int endIndex = name.replaceAll(META_WAL_PROVIDER_ID, "").lastIndexOf(".");
return name.substring(0, endIndex);
}
}