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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  
20  package org.apache.hadoop.hbase.io.hfile;
21  
22  import static org.junit.Assert.assertEquals;
23  import static org.junit.Assert.assertNotNull;
24  import static org.junit.Assert.assertTrue;
25  
26  import java.io.ByteArrayInputStream;
27  import java.io.DataInputStream;
28  import java.io.IOException;
29  import java.nio.ByteBuffer;
30  import java.util.ArrayList;
31  import java.util.List;
32  import java.util.Random;
33  
34  import org.apache.commons.logging.Log;
35  import org.apache.commons.logging.LogFactory;
36  import org.apache.hadoop.conf.Configuration;
37  import org.apache.hadoop.fs.FSDataInputStream;
38  import org.apache.hadoop.fs.FileSystem;
39  import org.apache.hadoop.fs.Path;
40  import org.apache.hadoop.hbase.HBaseTestingUtility;
41  import org.apache.hadoop.hbase.KeyValue;
42  import org.apache.hadoop.hbase.SmallTests;
43  import org.apache.hadoop.hbase.io.compress.Compression;
44  import org.apache.hadoop.hbase.io.compress.Compression.Algorithm;
45  import org.apache.hadoop.hbase.io.hfile.HFile.FileInfo;
46  import org.apache.hadoop.hbase.util.Bytes;
47  import org.apache.hadoop.hbase.util.Writables;
48  import org.apache.hadoop.io.RawComparator;
49  import org.apache.hadoop.io.Text;
50  import org.apache.hadoop.io.WritableUtils;
51  import org.junit.Before;
52  import org.junit.Test;
53  import org.junit.experimental.categories.Category;
54  
55  /**
56   * Testing writing a version 2 {@link HFile}. This is a low-level test written
57   * during the development of {@link HFileWriterV2}.
58   */
59  @Category(SmallTests.class)
60  public class TestHFileWriterV2 {
61  
62    private static final Log LOG = LogFactory.getLog(TestHFileWriterV2.class);
63  
64    private static final HBaseTestingUtility TEST_UTIL =
65        new HBaseTestingUtility();
66  
67    private Configuration conf;
68    private FileSystem fs;
69  
70    @Before
71    public void setUp() throws IOException {
72      conf = TEST_UTIL.getConfiguration();
73      fs = FileSystem.get(conf);
74    }
75  
76    @Test
77    public void testHFileFormatV2() throws IOException {
78      Path hfilePath = new Path(TEST_UTIL.getDataTestDir(), "testHFileFormatV2");
79      final Compression.Algorithm compressAlgo = Compression.Algorithm.GZ;
80      final int entryCount = 10000;
81      writeDataAndReadFromHFile(hfilePath, compressAlgo, entryCount, false);
82    }
83  
84    @Test
85    public void testMidKeyInHFile() throws IOException{
86      Path hfilePath = new Path(TEST_UTIL.getDataTestDir(),
87      "testMidKeyInHFile");
88      Compression.Algorithm compressAlgo = Compression.Algorithm.NONE;
89      int entryCount = 50000;
90      writeDataAndReadFromHFile(hfilePath, compressAlgo, entryCount, true);
91    }
92  
93    private void writeDataAndReadFromHFile(Path hfilePath,
94        Algorithm compressAlgo, int entryCount, boolean findMidKey) throws IOException {
95  
96      HFileWriterV2 writer = (HFileWriterV2)
97          new HFileWriterV2.WriterFactoryV2(conf, new CacheConfig(conf))
98              .withPath(fs, hfilePath)
99              .withBlockSize(4096)
100             .withCompression(compressAlgo)
101             .withComparator(KeyValue.KEY_COMPARATOR)
102             .create();
103 
104     Random rand = new Random(9713312); // Just a fixed seed.
105     List<KeyValue> keyValues = new ArrayList<KeyValue>(entryCount);
106 
107     for (int i = 0; i < entryCount; ++i) {
108       byte[] keyBytes = randomOrderedKey(rand, i);
109 
110       // A random-length random value.
111       byte[] valueBytes = randomValue(rand);
112       KeyValue keyValue = new KeyValue(keyBytes, null, null, valueBytes);
113       writer.append(keyValue);
114       keyValues.add(keyValue);
115     }
116 
117     // Add in an arbitrary order. They will be sorted lexicographically by
118     // the key.
119     writer.appendMetaBlock("CAPITAL_OF_USA", new Text("Washington, D.C."));
120     writer.appendMetaBlock("CAPITAL_OF_RUSSIA", new Text("Moscow"));
121     writer.appendMetaBlock("CAPITAL_OF_FRANCE", new Text("Paris"));
122 
123     writer.close();
124     
125 
126     FSDataInputStream fsdis = fs.open(hfilePath);
127 
128     // A "manual" version of a new-format HFile reader. This unit test was
129     // written before the V2 reader was fully implemented.
130 
131     long fileSize = fs.getFileStatus(hfilePath).getLen();
132     FixedFileTrailer trailer =
133         FixedFileTrailer.readFromStream(fsdis, fileSize);
134 
135     assertEquals(2, trailer.getMajorVersion());
136     assertEquals(entryCount, trailer.getEntryCount());
137 
138     HFileBlock.FSReader blockReader =
139         new HFileBlock.FSReaderV2(fsdis, compressAlgo, fileSize);
140     // Comparator class name is stored in the trailer in version 2.
141     RawComparator<byte []> comparator = trailer.createComparator();
142     HFileBlockIndex.BlockIndexReader dataBlockIndexReader =
143         new HFileBlockIndex.BlockIndexReader(comparator,
144             trailer.getNumDataIndexLevels());
145     HFileBlockIndex.BlockIndexReader metaBlockIndexReader =
146         new HFileBlockIndex.BlockIndexReader(
147             Bytes.BYTES_RAWCOMPARATOR, 1);
148 
149     HFileBlock.BlockIterator blockIter = blockReader.blockRange(
150         trailer.getLoadOnOpenDataOffset(),
151         fileSize - trailer.getTrailerSize());
152     // Data index. We also read statistics about the block index written after
153     // the root level.
154     dataBlockIndexReader.readMultiLevelIndexRoot(
155         blockIter.nextBlockWithBlockType(BlockType.ROOT_INDEX),
156         trailer.getDataIndexCount());
157     
158     if (findMidKey) {
159       byte[] midkey = dataBlockIndexReader.midkey();
160       assertNotNull("Midkey should not be null", midkey);
161     }
162     
163     // Meta index.
164     metaBlockIndexReader.readRootIndex(
165         blockIter.nextBlockWithBlockType(BlockType.ROOT_INDEX).getByteStream(),
166         trailer.getMetaIndexCount());
167     // File info
168     FileInfo fileInfo = new FileInfo();
169     fileInfo.read(blockIter.nextBlockWithBlockType(BlockType.FILE_INFO).getByteStream());
170     byte [] keyValueFormatVersion = fileInfo.get(
171         HFileWriterV2.KEY_VALUE_VERSION);
172     boolean includeMemstoreTS = keyValueFormatVersion != null &&
173         Bytes.toInt(keyValueFormatVersion) > 0;
174 
175     // Counters for the number of key/value pairs and the number of blocks
176     int entriesRead = 0;
177     int blocksRead = 0;
178     long memstoreTS = 0;
179 
180     // Scan blocks the way the reader would scan them
181     fsdis.seek(0);
182     long curBlockPos = 0;
183     while (curBlockPos <= trailer.getLastDataBlockOffset()) {
184       HFileBlock block = blockReader.readBlockData(curBlockPos, -1, -1, false);
185       assertEquals(BlockType.DATA, block.getBlockType());
186       ByteBuffer buf = block.getBufferWithoutHeader();
187       while (buf.hasRemaining()) {
188         int keyLen = buf.getInt();
189         int valueLen = buf.getInt();
190 
191         byte[] key = new byte[keyLen];
192         buf.get(key);
193 
194         byte[] value = new byte[valueLen];
195         buf.get(value);
196 
197         if (includeMemstoreTS) {
198           ByteArrayInputStream byte_input = new ByteArrayInputStream(buf.array(),
199                                buf.arrayOffset() + buf.position(), buf.remaining());
200           DataInputStream data_input = new DataInputStream(byte_input);
201 
202           memstoreTS = WritableUtils.readVLong(data_input);
203           buf.position(buf.position() + WritableUtils.getVIntSize(memstoreTS));
204         }
205 
206         // A brute-force check to see that all keys and values are correct.
207         assertTrue(Bytes.compareTo(key, keyValues.get(entriesRead).getKey()) == 0);
208         assertTrue(Bytes.compareTo(value, keyValues.get(entriesRead).getValue()) == 0);
209 
210         ++entriesRead;
211       }
212       ++blocksRead;
213       curBlockPos += block.getOnDiskSizeWithHeader();
214     }
215     LOG.info("Finished reading: entries=" + entriesRead + ", blocksRead="
216         + blocksRead);
217     assertEquals(entryCount, entriesRead);
218 
219     // Meta blocks. We can scan until the load-on-open data offset (which is
220     // the root block index offset in version 2) because we are not testing
221     // intermediate-level index blocks here.
222 
223     int metaCounter = 0;
224     while (fsdis.getPos() < trailer.getLoadOnOpenDataOffset()) {
225       LOG.info("Current offset: " + fsdis.getPos() + ", scanning until " +
226           trailer.getLoadOnOpenDataOffset());
227       HFileBlock block = blockReader.readBlockData(curBlockPos, -1, -1, false);
228       assertEquals(BlockType.META, block.getBlockType());
229       Text t = new Text();
230       ByteBuffer buf = block.getBufferWithoutHeader();
231       if (Writables.getWritable(buf.array(), buf.arrayOffset(), buf.limit(), t) == null) {
232         throw new IOException("Failed to deserialize block " + this + " into a " + t.getClass().getSimpleName());
233       }
234       Text expectedText =
235           (metaCounter == 0 ? new Text("Paris") : metaCounter == 1 ? new Text(
236               "Moscow") : new Text("Washington, D.C."));
237       assertEquals(expectedText, t);
238       LOG.info("Read meta block data: " + t);
239       ++metaCounter;
240       curBlockPos += block.getOnDiskSizeWithHeader();
241     }
242 
243     fsdis.close();
244   }
245 
246 
247   // Static stuff used by various HFile v2 unit tests
248 
249   private static final String COLUMN_FAMILY_NAME = "_-myColumnFamily-_";
250   private static final int MIN_ROW_OR_QUALIFIER_LENGTH = 64;
251   private static final int MAX_ROW_OR_QUALIFIER_LENGTH = 128;
252 
253   /**
254    * Generates a random key that is guaranteed to increase as the given index i
255    * increases. The result consists of a prefix, which is a deterministic
256    * increasing function of i, and a random suffix.
257    *
258    * @param rand
259    *          random number generator to use
260    * @param i
261    * @return
262    */
263   public static byte[] randomOrderedKey(Random rand, int i) {
264     StringBuilder k = new StringBuilder();
265 
266     // The fixed-length lexicographically increasing part of the key.
267     for (int bitIndex = 31; bitIndex >= 0; --bitIndex) {
268       if ((i & (1 << bitIndex)) == 0)
269         k.append("a");
270       else
271         k.append("b");
272     }
273 
274     // A random-length random suffix of the key.
275     for (int j = 0; j < rand.nextInt(50); ++j)
276       k.append(randomReadableChar(rand));
277 
278     byte[] keyBytes = k.toString().getBytes();
279     return keyBytes;
280   }
281 
282   public static byte[] randomValue(Random rand) {
283     StringBuilder v = new StringBuilder();
284     for (int j = 0; j < 1 + rand.nextInt(2000); ++j) {
285       v.append((char) (32 + rand.nextInt(95)));
286     }
287 
288     byte[] valueBytes = v.toString().getBytes();
289     return valueBytes;
290   }
291 
292   public static final char randomReadableChar(Random rand) {
293     int i = rand.nextInt(26 * 2 + 10 + 1);
294     if (i < 26)
295       return (char) ('A' + i);
296     i -= 26;
297 
298     if (i < 26)
299       return (char) ('a' + i);
300     i -= 26;
301 
302     if (i < 10)
303       return (char) ('0' + i);
304     i -= 10;
305 
306     assert i == 0;
307     return '_';
308   }
309 
310   public static byte[] randomRowOrQualifier(Random rand) {
311     StringBuilder field = new StringBuilder();
312     int fieldLen = MIN_ROW_OR_QUALIFIER_LENGTH
313         + rand.nextInt(MAX_ROW_OR_QUALIFIER_LENGTH
314             - MIN_ROW_OR_QUALIFIER_LENGTH + 1);
315     for (int i = 0; i < fieldLen; ++i)
316       field.append(randomReadableChar(rand));
317     return field.toString().getBytes();
318   }
319 
320   public static KeyValue randomKeyValue(Random rand) {
321     return new KeyValue(randomRowOrQualifier(rand),
322         COLUMN_FAMILY_NAME.getBytes(), randomRowOrQualifier(rand),
323         randomValue(rand));
324   }
325 
326 
327 }
328