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1   /**
2    * Licensed to the Apache Software Foundation (ASF) under one
3    * or more contributor license agreements.  See the NOTICE file
4    * distributed with this work for additional information
5    * regarding copyright ownership.  The ASF licenses this file
6    * to you under the Apache License, Version 2.0 (the
7    * "License"); you may not use this file except in compliance
8    * with the License.  You may obtain a copy of the License at
9    *
10   *     http://www.apache.org/licenses/LICENSE-2.0
11   *
12   * Unless required by applicable law or agreed to in writing, software
13   * distributed under the License is distributed on an "AS IS" BASIS,
14   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15   * See the License for the specific language governing permissions and
16   * limitations under the License.
17   */
18  package org.apache.hadoop.hbase.master.snapshot;
19  
20  import java.io.IOException;
21  import java.util.HashSet;
22  import java.util.List;
23  import java.util.Set;
24  import java.util.concurrent.ThreadPoolExecutor;
25  
26  import org.apache.commons.logging.Log;
27  import org.apache.commons.logging.LogFactory;
28  import org.apache.hadoop.hbase.HConstants;
29  import org.apache.hadoop.conf.Configuration;
30  import org.apache.hadoop.hbase.HConstants;
31  import org.apache.hadoop.hbase.classification.InterfaceAudience;
32  import org.apache.hadoop.hbase.classification.InterfaceStability;
33  import org.apache.hadoop.hbase.HRegionInfo;
34  import org.apache.hadoop.hbase.ServerName;
35  import org.apache.hadoop.hbase.client.RegionReplicaUtil;
36  import org.apache.hadoop.hbase.errorhandling.ForeignException;
37  import org.apache.hadoop.hbase.master.MasterServices;
38  import org.apache.hadoop.hbase.mob.MobUtils;
39  import org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.SnapshotDescription;
40  import org.apache.hadoop.hbase.snapshot.ClientSnapshotDescriptionUtils;
41  import org.apache.hadoop.hbase.snapshot.SnapshotManifest;
42  import org.apache.hadoop.hbase.util.FSUtils;
43  import org.apache.hadoop.hbase.util.ModifyRegionUtils;
44  import org.apache.hadoop.hbase.util.Pair;
45  import org.apache.zookeeper.KeeperException;
46  
47  /**
48   * Take a snapshot of a disabled table.
49   * <p>
50   * Table must exist when taking the snapshot, or results are undefined.
51   */
52  @InterfaceAudience.Private
53  @InterfaceStability.Evolving
54  public class DisabledTableSnapshotHandler extends TakeSnapshotHandler {
55    private static final Log LOG = LogFactory.getLog(DisabledTableSnapshotHandler.class);
56  
57    /**
58     * @param snapshot descriptor of the snapshot to take
59     * @param masterServices master services provider
60     */
61    public DisabledTableSnapshotHandler(SnapshotDescription snapshot,
62        final MasterServices masterServices) {
63      super(snapshot, masterServices);
64    }
65  
66    @Override
67    public DisabledTableSnapshotHandler prepare() throws Exception {
68      return (DisabledTableSnapshotHandler) super.prepare();
69    }
70  
71    // TODO consider parallelizing these operations since they are independent. Right now its just
72    // easier to keep them serial though
73    @Override
74    public void snapshotRegions(List<Pair<HRegionInfo, ServerName>> regionsAndLocations)
75        throws IOException, KeeperException {
76      try {
77        // 1. get all the regions hosting this table.
78  
79        // extract each pair to separate lists
80        Set<HRegionInfo> regions = new HashSet<HRegionInfo>();
81        for (Pair<HRegionInfo, ServerName> p : regionsAndLocations) {
82          // Don't include non-default regions
83          HRegionInfo hri = p.getFirst();
84          if (RegionReplicaUtil.isDefaultReplica(hri)) {
85            regions.add(hri);
86          }
87        }
88        // handle the mob files if any.
89        boolean mobEnabled = MobUtils.hasMobColumns(htd);
90        if (mobEnabled) {
91          // snapshot the mob files as a offline region.
92          HRegionInfo mobRegionInfo = MobUtils.getMobRegionInfo(htd.getTableName());
93          regions.add(mobRegionInfo);
94        }
95  
96        // 2. for each region, write all the info to disk
97        String msg = "Starting to write region info and WALs for regions for offline snapshot:"
98            + ClientSnapshotDescriptionUtils.toString(snapshot);
99        LOG.info(msg);
100       status.setStatus(msg);
101 
102       ThreadPoolExecutor exec = SnapshotManifest.createExecutor(conf, "DisabledTableSnapshot");
103       try {
104         ModifyRegionUtils.editRegions(exec, regions, new ModifyRegionUtils.RegionEditTask() {
105           @Override
106           public void editRegion(final HRegionInfo regionInfo) throws IOException {
107             snapshotManifest.addRegion(FSUtils.getTableDir(rootDir, snapshotTable), regionInfo);
108           }
109         });
110       } finally {
111         exec.shutdown();
112       }
113     } catch (Exception e) {
114       // make sure we capture the exception to propagate back to the client later
115       String reason = "Failed snapshot " + ClientSnapshotDescriptionUtils.toString(snapshot)
116           + " due to exception:" + e.getMessage();
117       ForeignException ee = new ForeignException(reason, e);
118       monitor.receive(ee);
119       status.abort("Snapshot of table: "+ snapshotTable + " failed because " + e.getMessage());
120     } finally {
121       LOG.debug("Marking snapshot" + ClientSnapshotDescriptionUtils.toString(snapshot)
122           + " as finished.");
123     }
124   }
125 }