HBASE-10348. HTableDescriptor changes for region replicas

git-svn-id: https://svn.apache.org/repos/asf/hbase/branches/hbase-10070@1565658 13f79535-47bb-0310-9956-ffa450edef68

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

@@ -182,6 +182,13 @@ public class HTableDescriptor implements WritableComparable<HTableDescriptor> {
   private static final ImmutableBytesWritable DURABILITY_KEY =
       new ImmutableBytesWritable(Bytes.toBytes("DURABILITY"));
 
+  /**
+   * <em>INTERNAL</em> number of region replicas for the table.
+   */
+  public static final String REGION_REPLICATION = "REGION_REPLICATION";
+  private static final ImmutableBytesWritable REGION_REPLICATION_KEY =
+      new ImmutableBytesWritable(Bytes.toBytes(REGION_REPLICATION));
+
   /** Default durability for HTD is USE_DEFAULT, which defaults to HBase-global default value */
   private static final Durability DEFAULT_DURABLITY = Durability.USE_DEFAULT;
 
@@ -214,6 +221,8 @@ public class HTableDescriptor implements WritableComparable<HTableDescriptor> {
    */
   public static final long DEFAULT_MEMSTORE_FLUSH_SIZE = 1024*1024*128L;
 
+  public static final int DEFAULT_REGION_REPLICATION = 1;
+
   private final static Map<String, String> DEFAULT_VALUES
     = new HashMap<String, String>();
   private final static Set<ImmutableBytesWritable> RESERVED_KEYWORDS
@@ -227,6 +236,7 @@ public class HTableDescriptor implements WritableComparable<HTableDescriptor> {
     DEFAULT_VALUES.put(DEFERRED_LOG_FLUSH,
         String.valueOf(DEFAULT_DEFERRED_LOG_FLUSH));
     DEFAULT_VALUES.put(DURABILITY, DEFAULT_DURABLITY.name()); //use the enum name
+    DEFAULT_VALUES.put(REGION_REPLICATION, String.valueOf(DEFAULT_REGION_REPLICATION));
     for (String s : DEFAULT_VALUES.keySet()) {
       RESERVED_KEYWORDS.add(new ImmutableBytesWritable(Bytes.toBytes(s)));
     }
@@ -1067,6 +1077,26 @@ public class HTableDescriptor implements WritableComparable<HTableDescriptor> {
     return Collections.unmodifiableCollection(this.families.values());
   }
 
+  /**
+   * Returns the configured replicas per region
+   */
+  public int getRegionReplication() {
+    byte[] val = getValue(REGION_REPLICATION_KEY);
+    if (val == null || val.length == 0) {
+      return DEFAULT_REGION_REPLICATION;
+    }
+    return Integer.parseInt(Bytes.toString(val));
+  }
+
+  /**
+   * Sets the number of replicas per region.
+   * @param regionReplication the replication factor per region
+   */
+  public void setRegionReplication(int regionReplication) {
+    setValue(REGION_REPLICATION_KEY,
+        new ImmutableBytesWritable(Bytes.toBytes(Integer.toString(regionReplication))));
+  }
+
   /**
    * Returns all the column family names of the current table. The map of
    * HTableDescriptor contains mapping of family name to HColumnDescriptors.

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

@@ -49,12 +49,14 @@ public class TestHTableDescriptor {
     htd.setMaxFileSize(v);
     htd.setDurability(Durability.ASYNC_WAL);
     htd.setReadOnly(true);
+    htd.setRegionReplication(2);
     byte [] bytes = htd.toByteArray();
     HTableDescriptor deserializedHtd = HTableDescriptor.parseFrom(bytes);
     assertEquals(htd, deserializedHtd);
     assertEquals(v, deserializedHtd.getMaxFileSize());
     assertTrue(deserializedHtd.isReadOnly());
     assertEquals(Durability.ASYNC_WAL, deserializedHtd.getDurability());
+    assertEquals(deserializedHtd.getRegionReplication(), 2);
   }
 
   /**

hbase-shell/src/main/ruby/hbase.rb

@@ -57,6 +57,7 @@ module HBaseConstants
   SPLITS_FILE = 'SPLITS_FILE'
   SPLITALGO = 'SPLITALGO'
   NUMREGIONS = 'NUMREGIONS'
+  REGION_REPLICATION = 'REGION_REPLICATION'
   CONFIGURATION = org.apache.hadoop.hbase.HConstants::CONFIGURATION
   ATTRIBUTES="ATTRIBUTES"
   VISIBILITY="VISIBILITY"

hbase-shell/src/main/ruby/hbase/admin.rb

@@ -220,6 +220,10 @@ module Hbase
           has_columns = true
           next
         end
+        if arg.has_key?(REGION_REPLICATION)
+          region_replication = JInteger.valueOf(arg.delete(REGION_REPLICATION))
+          htd.setRegionReplication(region_replication)
+        end 
         
         # Get rid of the "METHOD", which is deprecated for create.
         # We'll do whatever it used to do below if it's table_att.

hbase-shell/src/main/ruby/shell/commands/create.rb

@@ -49,7 +49,7 @@ Examples:
   hbase> # Optionally pre-split the table into NUMREGIONS, using
   hbase> # SPLITALGO ("HexStringSplit", "UniformSplit" or classname)
   hbase> create 't1', 'f1', {NUMREGIONS => 15, SPLITALGO => 'HexStringSplit'}
-  hbase> create 't1', 'f1', {NUMREGIONS => 15, SPLITALGO => 'HexStringSplit', CONFIGURATION => {'hbase.hregion.scan.loadColumnFamiliesOnDemand' => 'true'}}
+  hbase> create 't1', 'f1', {NUMREGIONS => 15, SPLITALGO => 'HexStringSplit', REGION_REPLICATION => 2, CONFIGURATION => {'hbase.hregion.scan.loadColumnFamiliesOnDemand' => 'true'}}
 
 You can also keep around a reference to the created table: