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.HConstants;
027import org.apache.hadoop.hbase.master.cleaner.BaseHFileCleanerDelegate;
028import org.apache.hadoop.hbase.master.cleaner.HFileCleaner;
029import org.apache.hadoop.hbase.replication.ReplicationException;
030import org.apache.hadoop.hbase.replication.ReplicationQueueStorage;
031import org.apache.hadoop.hbase.replication.ReplicationStorageFactory;
032import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
033import org.apache.yetus.audience.InterfaceAudience;
034import org.slf4j.Logger;
035import org.slf4j.LoggerFactory;
036
037import org.apache.hbase.thirdparty.com.google.common.base.Predicate;
038import org.apache.hbase.thirdparty.com.google.common.collect.Iterables;
039
040/**
041 * Implementation of a file cleaner that checks if a hfile is still scheduled for replication before
042 * deleting it from hfile archive directory.
043 */
044@InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.CONFIG)
045public class ReplicationHFileCleaner extends BaseHFileCleanerDelegate {
046  private static final Logger LOG = LoggerFactory.getLogger(ReplicationHFileCleaner.class);
047  private ZKWatcher zkw;
048  private ReplicationQueueStorage rqs;
049  private boolean stopped = false;
050
051  @Override
052  public Iterable<FileStatus> getDeletableFiles(Iterable<FileStatus> files) {
053    // all members of this class are null if replication is disabled,
054    // so we cannot filter the files
055    if (this.getConf() == null) {
056      return files;
057    }
058
059    final Set<String> hfileRefs;
060    try {
061      // The concurrently created new hfile entries in ZK may not be included in the return list,
062      // but they won't be deleted because they're not in the checking set.
063      hfileRefs = rqs.getAllHFileRefs();
064    } catch (ReplicationException e) {
065      LOG.warn("Failed to read hfile references from zookeeper, skipping checking deletable files");
066      return Collections.emptyList();
067    }
068    return Iterables.filter(files, new Predicate<FileStatus>() {
069      @Override
070      public boolean apply(FileStatus file) {
071        // just for overriding the findbugs NP warnings, as the parameter is marked as Nullable in
072        // the guava Predicate.
073        if (file == null) {
074          return false;
075        }
076        String hfile = file.getPath().getName();
077        boolean foundHFileRefInQueue = hfileRefs.contains(hfile);
078        if (LOG.isDebugEnabled()) {
079          if (foundHFileRefInQueue) {
080            LOG.debug("Found hfile reference in ZK, keeping: " + hfile);
081          } else {
082            LOG.debug("Did not find hfile reference in ZK, deleting: " + hfile);
083          }
084        }
085        return !foundHFileRefInQueue;
086      }
087    });
088  }
089
090  @Override
091  public void setConf(Configuration config) {
092    // If either replication or replication of bulk load hfiles is disabled, keep all members null
093    if (
094      !(config.getBoolean(HConstants.REPLICATION_BULKLOAD_ENABLE_KEY,
095        HConstants.REPLICATION_BULKLOAD_ENABLE_DEFAULT))
096    ) {
097      LOG.warn(HConstants.REPLICATION_BULKLOAD_ENABLE_KEY + " is not enabled. Better to remove "
098        + ReplicationHFileCleaner.class + " from " + HFileCleaner.MASTER_HFILE_CLEANER_PLUGINS
099        + " configuration.");
100      return;
101    }
102    // Make my own Configuration. Then I'll have my own connection to zk that
103    // I can close myself when time comes.
104    Configuration conf = new Configuration(config);
105    try {
106      setConf(conf, new ZKWatcher(conf, "replicationHFileCleaner", null));
107    } catch (IOException e) {
108      LOG.error("Error while configuring " + this.getClass().getName(), e);
109    }
110  }
111
112  @InterfaceAudience.Private
113  public void setConf(Configuration conf, ZKWatcher zk) {
114    super.setConf(conf);
115    try {
116      initReplicationQueueStorage(conf, zk);
117    } catch (Exception e) {
118      LOG.error("Error while configuring " + this.getClass().getName(), e);
119    }
120  }
121
122  private void initReplicationQueueStorage(Configuration conf, ZKWatcher zk) {
123    this.zkw = zk;
124    this.rqs = ReplicationStorageFactory.getReplicationQueueStorage(zk, conf);
125  }
126
127  @Override
128  public void stop(String why) {
129    if (this.stopped) {
130      return;
131    }
132    this.stopped = true;
133    if (this.zkw != null) {
134      LOG.info("Stopping " + this.zkw);
135      this.zkw.close();
136    }
137  }
138
139  @Override
140  public boolean isStopped() {
141    return this.stopped;
142  }
143
144  @Override
145  public boolean isFileDeletable(FileStatus fStat) {
146    Set<String> hfileRefsFromQueue;
147    // all members of this class are null if replication is disabled,
148    // so do not stop from deleting the file
149    if (getConf() == null) {
150      return true;
151    }
152
153    try {
154      hfileRefsFromQueue = rqs.getAllHFileRefs();
155    } catch (ReplicationException e) {
156      LOG.warn("Failed to read hfile references from zookeeper, skipping checking deletable "
157        + "file for " + fStat.getPath());
158      return false;
159    }
160    return !hfileRefsFromQueue.contains(fStat.getPath().getName());
161  }
162}