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1   /**
2    *
3    * Licensed to the Apache Software Foundation (ASF) under one
4    * or more contributor license agreements.  See the NOTICE file
5    * distributed with this work for additional information
6    * regarding copyright ownership.  The ASF licenses this file
7    * to you under the Apache License, Version 2.0 (the
8    * "License"); you may not use this file except in compliance
9    * with the License.  You may obtain a copy of the License at
10   *
11   *     http://www.apache.org/licenses/LICENSE-2.0
12   *
13   * Unless required by applicable law or agreed to in writing, software
14   * distributed under the License is distributed on an "AS IS" BASIS,
15   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16   * See the License for the specific language governing permissions and
17   * limitations under the License.
18   */
19  package org.apache.hadoop.hbase.mapreduce.replication;
20  
21  import java.io.IOException;
22  
23  import org.apache.commons.logging.Log;
24  import org.apache.commons.logging.LogFactory;
25  import org.apache.hadoop.conf.Configuration;
26  import org.apache.hadoop.hbase.*;
27  import org.apache.hadoop.hbase.client.HConnectable;
28  import org.apache.hadoop.hbase.client.HConnection;
29  import org.apache.hadoop.hbase.client.HConnectionManager;
30  import org.apache.hadoop.hbase.client.HTable;
31  import org.apache.hadoop.hbase.client.Put;
32  import org.apache.hadoop.hbase.client.Result;
33  import org.apache.hadoop.hbase.client.ResultScanner;
34  import org.apache.hadoop.hbase.client.Scan;
35  import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
36  import org.apache.hadoop.hbase.mapreduce.TableInputFormat;
37  import org.apache.hadoop.hbase.mapreduce.TableMapReduceUtil;
38  import org.apache.hadoop.hbase.mapreduce.TableMapper;
39  import org.apache.hadoop.hbase.replication.ReplicationException;
40  import org.apache.hadoop.hbase.replication.ReplicationFactory;
41  import org.apache.hadoop.hbase.replication.ReplicationPeer;
42  import org.apache.hadoop.hbase.replication.ReplicationPeers;
43  import org.apache.hadoop.hbase.util.Bytes;
44  import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
45  import org.apache.hadoop.hbase.zookeeper.ZKUtil;
46  import org.apache.hadoop.mapreduce.Job;
47  import org.apache.hadoop.mapreduce.lib.output.NullOutputFormat;
48  
49  /**
50   * This map-only job compares the data from a local table with a remote one.
51   * Every cell is compared and must have exactly the same keys (even timestamp)
52   * as well as same value. It is possible to restrict the job by time range and
53   * families. The peer id that's provided must match the one given when the
54   * replication stream was setup.
55   * <p>
56   * Two counters are provided, Verifier.Counters.GOODROWS and BADROWS. The reason
57   * for a why a row is different is shown in the map's log.
58   */
59  public class VerifyReplication {
60  
61    private static final Log LOG =
62        LogFactory.getLog(VerifyReplication.class);
63  
64    public final static String NAME = "verifyrep";
65    static long startTime = 0;
66    static long endTime = Long.MAX_VALUE;
67    static String tableName = null;
68    static String families = null;
69    static String peerId = null;
70  
71    /**
72     * Map-only comparator for 2 tables
73     */
74    public static class Verifier
75        extends TableMapper<ImmutableBytesWritable, Put> {
76  
77      public static enum Counters {GOODROWS, BADROWS}
78  
79      private ResultScanner replicatedScanner;
80  
81      /**
82       * Map method that compares every scanned row with the equivalent from
83       * a distant cluster.
84       * @param row  The current table row key.
85       * @param value  The columns.
86       * @param context  The current context.
87       * @throws IOException When something is broken with the data.
88       */
89      @Override
90      public void map(ImmutableBytesWritable row, final Result value,
91                      Context context)
92          throws IOException {
93        if (replicatedScanner == null) {
94          Configuration conf = context.getConfiguration();
95          final Scan scan = new Scan();
96          scan.setCaching(conf.getInt(TableInputFormat.SCAN_CACHEDROWS, 1));
97          long startTime = conf.getLong(NAME + ".startTime", 0);
98          long endTime = conf.getLong(NAME + ".endTime", Long.MAX_VALUE);
99          String families = conf.get(NAME + ".families", null);
100         if(families != null) {
101           String[] fams = families.split(",");
102           for(String fam : fams) {
103             scan.addFamily(Bytes.toBytes(fam));
104           }
105         }
106         scan.setTimeRange(startTime, endTime);
107         HConnectionManager.execute(new HConnectable<Void>(conf) {
108           @Override
109           public Void connect(HConnection conn) throws IOException {
110             String zkClusterKey = conf.get(NAME + ".peerQuorumAddress");
111             Configuration peerConf = HBaseConfiguration.create(conf);
112             ZKUtil.applyClusterKeyToConf(peerConf, zkClusterKey);
113 
114             HTable replicatedTable = new HTable(peerConf, conf.get(NAME + ".tableName"));
115             scan.setStartRow(value.getRow());
116             replicatedScanner = replicatedTable.getScanner(scan);
117             return null;
118           }
119         });
120       }
121       Result res = replicatedScanner.next();
122       try {
123         Result.compareResults(value, res);
124         context.getCounter(Counters.GOODROWS).increment(1);
125       } catch (Exception e) {
126         LOG.warn("Bad row", e);
127         context.getCounter(Counters.BADROWS).increment(1);
128       }
129     }
130 
131     protected void cleanup(Context context) {
132       if (replicatedScanner != null) {
133         replicatedScanner.close();
134         replicatedScanner = null;
135       }
136     }
137   }
138 
139   private static String getPeerQuorumAddress(final Configuration conf) throws IOException {
140     ZooKeeperWatcher localZKW = null;
141     ReplicationPeer peer = null;
142     try {
143       localZKW = new ZooKeeperWatcher(conf, "VerifyReplication",
144           new Abortable() {
145             @Override public void abort(String why, Throwable e) {}
146             @Override public boolean isAborted() {return false;}
147           });
148 
149       ReplicationPeers rp = ReplicationFactory.getReplicationPeers(localZKW, conf, localZKW);
150       rp.init();
151 
152       Configuration peerConf = rp.getPeerConf(peerId);
153       if (peerConf == null) {
154         throw new IOException("Couldn't get peer conf!");
155       }
156 
157       return ZKUtil.getZooKeeperClusterKey(peerConf);
158     } catch (ReplicationException e) {
159       throw new IOException(
160           "An error occured while trying to connect to the remove peer cluster", e);
161     } finally {
162       if (peer != null) {
163         peer.close();
164       }
165       if (localZKW != null) {
166         localZKW.close();
167       }
168     }
169   }
170 
171   /**
172    * Sets up the actual job.
173    *
174    * @param conf  The current configuration.
175    * @param args  The command line parameters.
176    * @return The newly created job.
177    * @throws java.io.IOException When setting up the job fails.
178    */
179   public static Job createSubmittableJob(Configuration conf, String[] args)
180   throws IOException {
181     if (!doCommandLine(args)) {
182       return null;
183     }
184     if (!conf.getBoolean(HConstants.REPLICATION_ENABLE_KEY,
185         HConstants.REPLICATION_ENABLE_DEFAULT)) {
186       throw new IOException("Replication needs to be enabled to verify it.");
187     }
188     conf.set(NAME+".peerId", peerId);
189     conf.set(NAME+".tableName", tableName);
190     conf.setLong(NAME+".startTime", startTime);
191     conf.setLong(NAME+".endTime", endTime);
192     if (families != null) {
193       conf.set(NAME+".families", families);
194     }
195 
196     String peerQuorumAddress = getPeerQuorumAddress(conf);
197     conf.set(NAME + ".peerQuorumAddress", peerQuorumAddress);
198     LOG.info("Peer Quorum Address: " + peerQuorumAddress);
199 
200     Job job = new Job(conf, NAME + "_" + tableName);
201     job.setJarByClass(VerifyReplication.class);
202 
203     Scan scan = new Scan();
204     scan.setTimeRange(startTime, endTime);
205     if(families != null) {
206       String[] fams = families.split(",");
207       for(String fam : fams) {
208         scan.addFamily(Bytes.toBytes(fam));
209       }
210     }
211     TableMapReduceUtil.initTableMapperJob(tableName, scan,
212         Verifier.class, null, null, job);
213 
214     // Obtain the auth token from peer cluster
215     TableMapReduceUtil.initCredentialsForCluster(job, peerQuorumAddress);
216 
217     job.setOutputFormatClass(NullOutputFormat.class);
218     job.setNumReduceTasks(0);
219     return job;
220   }
221 
222   private static boolean doCommandLine(final String[] args) {
223     if (args.length < 2) {
224       printUsage(null);
225       return false;
226     }
227     try {
228       for (int i = 0; i < args.length; i++) {
229         String cmd = args[i];
230         if (cmd.equals("-h") || cmd.startsWith("--h")) {
231           printUsage(null);
232           return false;
233         }
234 
235         final String startTimeArgKey = "--starttime=";
236         if (cmd.startsWith(startTimeArgKey)) {
237           startTime = Long.parseLong(cmd.substring(startTimeArgKey.length()));
238           continue;
239         }
240 
241         final String endTimeArgKey = "--endtime=";
242         if (cmd.startsWith(endTimeArgKey)) {
243           endTime = Long.parseLong(cmd.substring(endTimeArgKey.length()));
244           continue;
245         }
246 
247         final String familiesArgKey = "--families=";
248         if (cmd.startsWith(familiesArgKey)) {
249           families = cmd.substring(familiesArgKey.length());
250           continue;
251         }
252 
253         if (i == args.length-2) {
254           peerId = cmd;
255         }
256 
257         if (i == args.length-1) {
258           tableName = cmd;
259         }
260       }
261     } catch (Exception e) {
262       e.printStackTrace();
263       printUsage("Can't start because " + e.getMessage());
264       return false;
265     }
266     return true;
267   }
268 
269   /*
270    * @param errorMsg Error message.  Can be null.
271    */
272   private static void printUsage(final String errorMsg) {
273     if (errorMsg != null && errorMsg.length() > 0) {
274       System.err.println("ERROR: " + errorMsg);
275     }
276     System.err.println("Usage: verifyrep [--starttime=X]" +
277         " [--stoptime=Y] [--families=A] <peerid> <tablename>");
278     System.err.println();
279     System.err.println("Options:");
280     System.err.println(" starttime    beginning of the time range");
281     System.err.println("              without endtime means from starttime to forever");
282     System.err.println(" endtime      end of the time range");
283     System.err.println(" families     comma-separated list of families to copy");
284     System.err.println();
285     System.err.println("Args:");
286     System.err.println(" peerid       Id of the peer used for verification, must match the one given for replication");
287     System.err.println(" tablename    Name of the table to verify");
288     System.err.println();
289     System.err.println("Examples:");
290     System.err.println(" To verify the data replicated from TestTable for a 1 hour window with peer #5 ");
291     System.err.println(" $ bin/hbase " +
292         "org.apache.hadoop.hbase.mapreduce.replication.VerifyReplication" +
293         " --starttime=1265875194289 --endtime=1265878794289 5 TestTable ");
294   }
295 
296   /**
297    * Main entry point.
298    *
299    * @param args  The command line parameters.
300    * @throws Exception When running the job fails.
301    */
302   public static void main(String[] args) throws Exception {
303     Configuration conf = HBaseConfiguration.create();
304     Job job = createSubmittableJob(conf, args);
305     if (job != null) {
306       System.exit(job.waitForCompletion(true) ? 0 : 1);
307     }
308   }
309 }