HBASE-7339 Splitting an HFileLink causes region servers to go down.

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/hbase-7290@1445806 13f79535-47bb-0310-9956-ffa450edef68

hbase-server/src/main/java/org/apache/hadoop/hbase/HTableDescriptor.java

@@ -396,6 +396,9 @@ public class HTableDescriptor implements WritableComparable<HTableDescriptor> {
       Bytes.equals(tableName, HConstants.META_TABLE_NAME);
   }
 
+  // A non-capture group so that this can be embedded.
+  public static final String VALID_USER_TABLE_REGEX = "(?:[a-zA-Z_0-9][a-zA-Z_0-9.-]*)";
+
   /**
    * Check passed byte buffer, "tableName", is legal user-space table name.
    * @return Returns passed <code>tableName</code> param

hbase-server/src/main/java/org/apache/hadoop/hbase/io/HalfStoreFileReader.java

@@ -59,10 +59,12 @@ public class HalfStoreFileReader extends StoreFile.Reader {
   private boolean firstKeySeeked = false;
 
   /**
-   * @param fs
+   * Creates a half file reader for a normal hfile.
-   * @param p
+   * @param fs fileystem to read from
+   * @param p path to hfile
    * @param cacheConf
-   * @param r
+   * @param r original reference file (contains top or bottom)
+   * @param preferredEncodingInCache
    * @throws IOException
    */
   public HalfStoreFileReader(final FileSystem fs, final Path p,
@@ -79,6 +81,30 @@ public class HalfStoreFileReader extends StoreFile.Reader {
     this.top = Reference.isTopFileRegion(r.getFileRegion());
   }
 
+  /**
+   * Creates a half file reader for a hfile referred to by an hfilelink.
+   * @param fs fileystem to read from
+   * @param p path to hfile
+   * @param link
+   * @param cacheConf
+   * @param r original reference file (contains top or bottom)
+   * @param preferredEncodingInCache
+   * @throws IOException
+   */
+  public HalfStoreFileReader(final FileSystem fs, final Path p, final HFileLink link,
+      final CacheConfig cacheConf, final Reference r,
+      DataBlockEncoding preferredEncodingInCache) throws IOException {
+    super(fs, p, link, link.getFileStatus(fs).getLen(), cacheConf, preferredEncodingInCache, true);
+    // This is not actual midkey for this half-file; its just border
+    // around which we split top and bottom.  Have to look in files to find
+    // actual last and first keys for bottom and top halves.  Half-files don't
+    // have an actual midkey themselves. No midkey is how we indicate file is
+    // not splittable.
+    this.splitkey = r.getSplitKey();
+    // Is it top or bottom half?
+    this.top = Reference.isTopFileRegion(r.getFileRegion());
+  }
+
   protected boolean isTop() {
     return this.top;
   }

hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/StoreFile.java

@@ -43,29 +43,29 @@ import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.HDFSBlocksDistribution;
+import org.apache.hadoop.hbase.HTableDescriptor;
 import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.KeyValue.KVComparator;
 import org.apache.hadoop.hbase.client.Scan;
-import org.apache.hadoop.hbase.io.HFileLink;
 import org.apache.hadoop.hbase.fs.HFileSystem;
+import org.apache.hadoop.hbase.io.HFileLink;
 import org.apache.hadoop.hbase.io.HalfStoreFileReader;
 import org.apache.hadoop.hbase.io.Reference;
 import org.apache.hadoop.hbase.io.compress.Compression;
 import org.apache.hadoop.hbase.io.encoding.DataBlockEncoding;
-import org.apache.hadoop.hbase.io.hfile.CacheConfig;
 import org.apache.hadoop.hbase.io.hfile.BlockType;
+import org.apache.hadoop.hbase.io.hfile.CacheConfig;
 import org.apache.hadoop.hbase.io.hfile.HFile;
+import org.apache.hadoop.hbase.io.hfile.HFileDataBlockEncoder;
 import org.apache.hadoop.hbase.io.hfile.HFileScanner;
 import org.apache.hadoop.hbase.io.hfile.HFileWriterV1;
 import org.apache.hadoop.hbase.io.hfile.HFileWriterV2;
-import org.apache.hadoop.hbase.io.hfile.HFileDataBlockEncoder;
 import org.apache.hadoop.hbase.io.hfile.NoOpDataBlockEncoder;
-import org.apache.hadoop.hbase.util.ChecksumType;
 import org.apache.hadoop.hbase.util.BloomFilter;
 import org.apache.hadoop.hbase.util.BloomFilterFactory;
 import org.apache.hadoop.hbase.util.BloomFilterWriter;
 import org.apache.hadoop.hbase.util.Bytes;
-import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
+import org.apache.hadoop.hbase.util.ChecksumType;
 import org.apache.hadoop.hbase.util.FSUtils;
 import org.apache.hadoop.hbase.util.Writables;
 import org.apache.hadoop.io.RawComparator;
@@ -200,13 +200,25 @@ public class StoreFile {
    */
   private Map<byte[], byte[]> metadataMap;
 
-  /*
+  /**
-   * Regex that will work for straight filenames and for reference names.
+   * Regex that will work for straight filenames (<hfile>) and for reference names
-   * If reference, then the regex has more than just one group.  Group 1 is
+   * (<hfile>.<parentEncRegion>).  If reference, then the regex has more than just one group.
-   * this files id.  Group 2 the referenced region name, etc.
+   * Group 1, '([0-9a-f]+(?:_SeqId_[0-9]+_0?)',  is this file's id.  Group 2 '(.+)' is the
+   * reference's parent region name.  The ?: paren expressions are non-capture markers so not
+   * included in the groups count. The _SeqId_ portion comes from bulk loaded files.
    */
-  private static final Pattern REF_NAME_PARSER =
+  public static final String REF_NAME_REGEX = "^([0-9a-f]+(?:_SeqId_[0-9]+_)?)(?:\\.(.+))?$";
-    Pattern.compile("^([0-9a-f]+(?:_SeqId_[0-9]+_)?)(?:\\.(.+))?$");
+  private static final Pattern REF_NAME_PARSER = Pattern.compile(REF_NAME_REGEX);
+
+  /**
+   * Regex strictly for references to hfilelinks.  (<hfile>-<region>-<table>.<parentEncRegion>).
+   * Group 1 is this file's hfilelink name.  Group 2 the referenced parent region name.  The '.'
+   * char is valid in table names but group 2's regex is greedy and interprets the table names
+   * correctly.   The _SeqId_ portion comes from bulk loaded files.
+   */
+  public static final String REF_TO_LINK_REGEX = "^([0-9a-f]+(?:_SeqId_[0-9]+_)?-[0-9a-f]+-"
+      + HTableDescriptor.VALID_USER_TABLE_REGEX + "+)\\.([^.]+)$";
+  private static final Pattern REF_TO_LINK_PARSER = Pattern.compile(REF_TO_LINK_REGEX);
 
   // StoreFile.Reader
   private volatile Reader reader;
@@ -256,7 +268,6 @@ public class StoreFile {
     } else if (isReference(p)) {
       this.reference = Reference.read(fs, p);
       this.referencePath = getReferredToFile(this.path);
-      LOG.debug("Store file " + p + " is a reference");
     }
 
     if (BloomFilterFactory.isGeneralBloomEnabled(conf)) {
@@ -334,13 +345,38 @@ public class StoreFile {
    * hierarchy of <code>${hbase.rootdir}/tablename/regionname/familyname</code>.
    * @param p Path to a Reference file.
    * @return Calculated path to parent region file.
-   * @throws IOException
+   * @throws IllegalArgumentException when path regex fails to match.
    */
   static Path getReferredToFile(final Path p) {
     Matcher m = REF_NAME_PARSER.matcher(p.getName());
     if (m == null || !m.matches()) {
       LOG.warn("Failed match of store file name " + p.toString());
-      throw new RuntimeException("Failed match of store file name " +
+      throw new IllegalArgumentException("Failed match of store file name " +
+          p.toString());
+    }
+    // Other region name is suffix on the passed Reference file name
+    String otherRegion = m.group(2);
+    // Tabledir is up two directories from where Reference was written.
+    Path tableDir = p.getParent().getParent().getParent();
+    String nameStrippedOfSuffix = m.group(1);
+    // Build up new path with the referenced region in place of our current
+    // region in the reference path.  Also strip regionname suffix from name.
+    return new Path(new Path(new Path(tableDir, otherRegion),
+      p.getParent().getName()), nameStrippedOfSuffix);
+  }
+
+  /*
+   * Return path to an hfilelink referred to by a Reference.  Presumes a directory
+   * hierarchy of <code>${hbase.rootdir}/tablename/regionname/familyname</code>.
+   * @param p Path to a Reference to hfilelink file.
+   * @return Calculated path to parent region file.
+   * @throws IllegalArgumentException when path regex fails to match.
+   */
+  static Path getReferredToLink(final Path p) {
+    Matcher m = REF_TO_LINK_PARSER.matcher(p.getName());
+    if (m == null || !m.matches()) {
+      LOG.warn("Failed match of ref to hfilelink name" + p.toString());
+      throw new IllegalArgumentException("Failed match of ref to hfilelink name " +
           p.toString());
     }
     // Other region name is suffix on the passed Reference file name
@@ -534,9 +570,33 @@ public class StoreFile {
           this.cacheConf, this.reference,
           dataBlockEncoder.getEncodingInCache());
     } else if (isLink()) {
+      try {
         long size = link.getFileStatus(fs).getLen();
         this.reader = new Reader(this.fs, this.path, link, size, this.cacheConf,
             dataBlockEncoder.getEncodingInCache(), true);
+      } catch (FileNotFoundException fnfe) {
+        // This didn't actually link to another file!
+
+        // Handles the case where a file with the hfilelink pattern is actually a daughter
+        // reference to a hfile link.  This can occur when a cloned table's hfilelinks get split.
+        FileStatus actualRef = fs.getFileStatus(path);
+        long actualLen = actualRef.getLen();
+        if (actualLen == 0) {
+          LOG.error(path + " is a 0-len file, and actually an hfilelink missing target file!", fnfe);
+          throw fnfe;
+        }
+        LOG.debug("Size of link file is " + actualLen + "!= 0; treating as a reference to" +
+            " HFileLink " + path + "!");
+        this.reference = Reference.read(fs, this.path);
+        this.referencePath = getReferredToLink(this.path);
+        LOG.debug("Reference file "+ path + " referred to " + referencePath + "!");
+        link = new HFileLink(fs.getConf(), referencePath);
+        this.reader = new HalfStoreFileReader(this.fs, this.referencePath, link,
+            this.cacheConf, this.reference,
+            dataBlockEncoder.getEncodingInCache());
+        LOG.debug("Store file " + path + " is loaded " + referencePath + " as a half store file" +
+            " reader to an HFileLink!");
+      }
     } else {
       this.reader = new Reader(this.fs, this.path, this.cacheConf,
           dataBlockEncoder.getEncodingInCache());

hbase-server/src/test/java/org/apache/hadoop/hbase/TestHTableDescriptor.java

@@ -20,10 +20,15 @@ package org.apache.hadoop.hbase;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
 
 import java.io.IOException;
+import java.util.regex.Pattern;
 
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.hbase.coprocessor.BaseRegionObserver;
+import org.apache.hadoop.hbase.util.Bytes;
 import org.junit.Test;
 import org.junit.experimental.categories.Category;
 
@@ -32,6 +37,8 @@ import org.junit.experimental.categories.Category;
  */
 @Category(SmallTests.class)
 public class TestHTableDescriptor {
+  final static Log LOG = LogFactory.getLog(TestHTableDescriptor.class);
+
   @Test
   public void testPb() throws DeserializationException, IOException {
     HTableDescriptor htd = HTableDescriptor.META_TABLEDESC;
@@ -78,4 +85,42 @@ public class TestHTableDescriptor {
     desc.remove(key);
     assertEquals(null, desc.getValue(key));
   }
+
+  String legalTableNames[] = { "foo", "with-dash_under.dot", "_under_start_ok",  };
+  String illegalTableNames[] = { ".dot_start_illegal", "-dash_start_illegal", "spaces not ok" };
+
+  @Test
+  public void testLegalHTableNames() {
+    for (String tn : legalTableNames) {
+      HTableDescriptor.isLegalTableName(Bytes.toBytes(tn));
+    }
+  }
+
+  @Test
+  public void testIllegalHTableNames() {
+    for (String tn : illegalTableNames) {
+      try {
+        HTableDescriptor.isLegalTableName(Bytes.toBytes(tn));
+        fail("invalid tablename " + tn + " should have failed");
+      } catch (Exception e) {
+        // expected
+      }
+    }
+  }
+
+  @Test
+  public void testLegalHTableNamesRegex() {
+    for (String tn : legalTableNames) {
+      LOG.info("Testing: '" + tn + "'");
+      assertTrue(Pattern.matches(HTableDescriptor.VALID_USER_TABLE_REGEX, tn));
+    }
+  }
+
+  @Test
+  public void testIllegalHTableNamesRegex() {
+    for (String tn : illegalTableNames) {
+      LOG.info("Testing: '" + tn + "'");
+      assertFalse(Pattern.matches(HTableDescriptor.VALID_USER_TABLE_REGEX, tn));
+    }
+  }
 }

hbase-server/src/test/java/org/apache/hadoop/hbase/regionserver/TestStoreFile.java

@@ -27,10 +27,12 @@ import java.util.Comparator;
 import java.util.List;
 import java.util.Map;
 import java.util.TreeSet;
+import java.util.regex.Pattern;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.FileStatus;
 import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hbase.HBaseTestCase;
@@ -40,6 +42,8 @@ import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.SmallTests;
 import org.apache.hadoop.hbase.client.Scan;
 import org.apache.hadoop.hbase.io.HFileLink;
+import org.apache.hadoop.hbase.io.HalfStoreFileReader;
+import org.apache.hadoop.hbase.io.Reference;
 import org.apache.hadoop.hbase.io.encoding.DataBlockEncoding;
 import org.apache.hadoop.hbase.io.hfile.BlockCache;
 import org.apache.hadoop.hbase.io.hfile.CacheConfig;
@@ -105,6 +109,10 @@ public class TestStoreFile extends HBaseTestCase {
   private void writeStoreFile(final StoreFile.Writer writer) throws IOException {
     writeStoreFile(writer, Bytes.toBytes(getName()), Bytes.toBytes(getName()));
   }
+  
+  // pick an split point (roughly halfway)
+  byte[] SPLITKEY = new byte[] { (LAST_CHAR-FIRST_CHAR)/2, FIRST_CHAR};
+
   /*
    * Writes HStoreKey and ImmutableBytes data to passed writer and
    * then closes it.
@@ -208,6 +216,99 @@ public class TestStoreFile extends HBaseTestCase {
     assertEquals((LAST_CHAR - FIRST_CHAR + 1) * (LAST_CHAR - FIRST_CHAR + 1), count);
   }
 
+  /**
+   * Validate that we can handle valid tables with '.', '_', and '-' chars.
+   */
+  public void testRefToHFileRegex() {
+    String[] legal = { "aaaa-bbbb-tablename.cccc", "aaaa-bbbb-table.with.dots.cccc",
+          "aaaa-bbbb-table-with-dashes.cccc", "aaaa-bbbb-table_with_unders.cccc",
+          "aaaa-bbbb-_table_starts_unders.cccc"};
+    for (String refToHFile : legal) {
+      LOG.info("Validating regex for '" + refToHFile + "'");
+      assertTrue(Pattern.matches(StoreFile.REF_TO_LINK_REGEX, refToHFile));
+    }
+    
+    String[] illegal = { "aaaa-bbbb--flkaj.cccc", "aaaa-bbbb-.flkaj.cccc" };
+    for (String bad : illegal) {
+      assertFalse(Pattern.matches(StoreFile.REF_TO_LINK_REGEX, bad));
+    }
+  }
+
+  /**
+   * This test creates an hfile and then the dir structures and files to verify that references
+   * to hfilelinks (created by snapshot clones) can be properly interpreted.
+   */
+  public void testReferenceToHFileLink() throws IOException {
+    final String columnFamily = "f";
+    String tablename = "_original-evil-name"; // adding legal table name chars to verify regex handles it.
+    HRegionInfo hri = new HRegionInfo(Bytes.toBytes(tablename));
+    // store dir = <root>/<tablename>/<rgn>/<cf>
+    Path storedir = new Path(new Path(FSUtils.getRootDir(conf),
+      new Path(hri.getTableNameAsString(), hri.getEncodedName())), columnFamily);
+
+    // Make a store file and write data to it. <root>/<tablename>/<rgn>/<cf>/<file>
+    StoreFile.Writer writer = new StoreFile.WriterBuilder(conf, cacheConf,
+         this.fs, 8 * 1024)
+            .withOutputDir(storedir)
+            .build();
+    Path storeFilePath = writer.getPath();
+    writeStoreFile(writer);
+    writer.close();
+
+    // create link to store file. <root>/clone/region/<cf>/<hfile>-<region>-<table>
+    String target = "clone";
+    Path dstPath = new Path(FSUtils.getRootDir(conf), new Path(new Path(target, "region"), columnFamily));
+    HFileLink.create(conf, this.fs, dstPath, hri, storeFilePath.getName());
+    Path linkFilePath = new Path(dstPath,
+                  HFileLink.createHFileLinkName(hri, storeFilePath.getName()));
+
+    // create splits of the link.
+    // <root>/clone/splitA/<cf>/<reftohfilelink>,
+    // <root>/clone/splitB/<cf>/<reftohfilelink>
+    Path splitDirA = new Path(new Path(FSUtils.getRootDir(conf),
+        new Path(target, "splitA")), columnFamily);
+    Path splitDirB = new Path(new Path(FSUtils.getRootDir(conf),
+        new Path(target, "splitB")), columnFamily);
+    StoreFile f = new StoreFile(fs, linkFilePath, conf, cacheConf, BloomType.NONE,
+        NoOpDataBlockEncoder.INSTANCE);
+    byte[] splitRow = SPLITKEY;
+    Path pathA = StoreFile.split(fs, splitDirA, f, splitRow, true); // top
+    Path pathB = StoreFile.split(fs, splitDirB, f, splitRow, false); // bottom
+
+    // OK test the thing
+    FSUtils.logFileSystemState(fs, FSUtils.getRootDir(conf), LOG);
+
+    // There is a case where a file with the hfilelink pattern is actually a daughter
+    // reference to a hfile link.  This code in StoreFile that handles this case.
+    
+    // Try to open store file from link
+    StoreFile hsfA = new StoreFile(this.fs, pathA,  conf, cacheConf,
+        StoreFile.BloomType.NONE, NoOpDataBlockEncoder.INSTANCE);
+
+    // Now confirm that I can read from the ref to link
+    int count = 1;
+    HFileScanner s = hsfA.createReader().getScanner(false, false);
+    s.seekTo();
+    while (s.next()) {
+      count++;
+    }
+    assertTrue(count > 0); // read some rows here
+    
+    // Try to open store file from link
+    StoreFile hsfB = new StoreFile(this.fs, pathB,  conf, cacheConf,
+        StoreFile.BloomType.NONE, NoOpDataBlockEncoder.INSTANCE);
+
+    // Now confirm that I can read from the ref to link
+    HFileScanner sB = hsfB.createReader().getScanner(false, false);
+    sB.seekTo();
+    while (sB.next()) {
+      count++;
+    }
+
+    // read the rest of the rows
+    assertEquals((LAST_CHAR - FIRST_CHAR + 1) * (LAST_CHAR - FIRST_CHAR + 1), count);
+  }
+
   private void checkHalfHFile(final StoreFile f)
   throws IOException {
     byte [] midkey = f.createReader().midkey();