001/**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.hbase.replication.master;
019
020import java.io.IOException;
021import java.util.Collections;
022import java.util.Set;
023import org.apache.hadoop.conf.Configuration;
024import org.apache.hadoop.fs.FileStatus;
025import org.apache.hadoop.hbase.HBaseInterfaceAudience;
026import org.apache.hadoop.hbase.master.cleaner.BaseLogCleanerDelegate;
027import org.apache.hadoop.hbase.replication.ReplicationException;
028import org.apache.hadoop.hbase.replication.ReplicationQueueStorage;
029import org.apache.hadoop.hbase.replication.ReplicationStorageFactory;
030import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
031import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
032import org.apache.yetus.audience.InterfaceAudience;
033import org.slf4j.Logger;
034import org.slf4j.LoggerFactory;
035
036import org.apache.hbase.thirdparty.com.google.common.base.Predicate;
037import org.apache.hbase.thirdparty.com.google.common.collect.Iterables;
038
039/**
040 * Implementation of a log cleaner that checks if a log is still scheduled for
041 * replication before deleting it when its TTL is over.
042 */
043@InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.CONFIG)
044public class ReplicationLogCleaner extends BaseLogCleanerDelegate {
045  private static final Logger LOG = LoggerFactory.getLogger(ReplicationLogCleaner.class);
046  private ZKWatcher zkw;
047  private ReplicationQueueStorage queueStorage;
048  private boolean stopped = false;
049  private Set<String> wals;
050  private long readZKTimestamp = 0;
051
052  @Override
053  public void preClean() {
054    readZKTimestamp = EnvironmentEdgeManager.currentTime();
055    try {
056      // The concurrently created new WALs may not be included in the return list,
057      // but they won't be deleted because they're not in the checking set.
058      wals = queueStorage.getAllWALs();
059    } catch (ReplicationException e) {
060      LOG.warn("Failed to read zookeeper, skipping checking deletable files");
061      wals = null;
062    }
063  }
064
065  @Override
066  public Iterable<FileStatus> getDeletableFiles(Iterable<FileStatus> files) {
067    // all members of this class are null if replication is disabled,
068    // so we cannot filter the files
069    if (this.getConf() == null) {
070      return files;
071    }
072
073    if (wals == null) {
074      return Collections.emptyList();
075    }
076    return Iterables.filter(files, new Predicate<FileStatus>() {
077      @Override
078      public boolean apply(FileStatus file) {
079        // just for overriding the findbugs NP warnings, as the parameter is marked as Nullable in
080        // the guava Predicate.
081        if (file == null) {
082          return false;
083        }
084        String wal = file.getPath().getName();
085        boolean logInReplicationQueue = wals.contains(wal);
086        if (logInReplicationQueue) {
087          LOG.debug("Found up in ZooKeeper, NOT deleting={}", wal);
088        }
089        return !logInReplicationQueue && (file.getModificationTime() < readZKTimestamp);
090      }
091    });
092  }
093
094  @Override
095  public void setConf(Configuration config) {
096    // Make my own Configuration.  Then I'll have my own connection to zk that
097    // I can close myself when comes time.
098    Configuration conf = new Configuration(config);
099    try {
100      setConf(conf, new ZKWatcher(conf, "replicationLogCleaner", null));
101    } catch (IOException e) {
102      LOG.error("Error while configuring " + this.getClass().getName(), e);
103    }
104  }
105
106  @InterfaceAudience.Private
107  public void setConf(Configuration conf, ZKWatcher zk) {
108    super.setConf(conf);
109    try {
110      this.zkw = zk;
111      this.queueStorage = ReplicationStorageFactory.getReplicationQueueStorage(zk, conf);
112    } catch (Exception e) {
113      LOG.error("Error while configuring " + this.getClass().getName(), e);
114    }
115  }
116  
117  @Override
118  public void stop(String why) {
119    if (this.stopped) return;
120    this.stopped = true;
121    if (this.zkw != null) {
122      LOG.info("Stopping " + this.zkw);
123      this.zkw.close();
124    }
125  }
126
127  @Override
128  public boolean isStopped() {
129    return this.stopped;
130  }
131}