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Posted to commits@hbase.apache.org by te...@apache.org on 2015/02/20 19:18:59 UTC
hbase git commit: HBASE-13057 Provide client utility to easily enable
and disable table replication (Ashish Singhi)
Repository: hbase
Updated Branches:
refs/heads/master 229b0774c -> 9a311303a
HBASE-13057 Provide client utility to easily enable and disable table replication (Ashish Singhi)
Project: http://git-wip-us.apache.org/repos/asf/hbase/repo
Commit: http://git-wip-us.apache.org/repos/asf/hbase/commit/9a311303
Tree: http://git-wip-us.apache.org/repos/asf/hbase/tree/9a311303
Diff: http://git-wip-us.apache.org/repos/asf/hbase/diff/9a311303
Branch: refs/heads/master
Commit: 9a311303a88d355f8c982d2f3cc77bd6427dfb80
Parents: 229b077
Author: tedyu <yu...@gmail.com>
Authored: Fri Feb 20 10:18:47 2015 -0800
Committer: tedyu <yu...@gmail.com>
Committed: Fri Feb 20 10:18:47 2015 -0800
----------------------------------------------------------------------
.../client/replication/ReplicationAdmin.java | 207 +++++++++++++++++++
.../TestReplicationAdminWithClusters.java | 163 +++++++++++++++
.../src/main/ruby/hbase/replication_admin.rb | 13 ++
hbase-shell/src/main/ruby/shell.rb | 2 +
.../shell/commands/disable_table_replication.rb | 42 ++++
.../shell/commands/enable_table_replication.rb | 42 ++++
6 files changed, 469 insertions(+)
----------------------------------------------------------------------
http://git-wip-us.apache.org/repos/asf/hbase/blob/9a311303/hbase-client/src/main/java/org/apache/hadoop/hbase/client/replication/ReplicationAdmin.java
----------------------------------------------------------------------
diff --git a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/replication/ReplicationAdmin.java b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/replication/ReplicationAdmin.java
index 2d5c5e9..ca66fb3 100644
--- a/hbase-client/src/main/java/org/apache/hadoop/hbase/client/replication/ReplicationAdmin.java
+++ b/hbase-client/src/main/java/org/apache/hadoop/hbase/client/replication/ReplicationAdmin.java
@@ -38,17 +38,25 @@ import org.apache.hadoop.hbase.HColumnDescriptor;
import org.apache.hadoop.hbase.HConstants;
import org.apache.hadoop.hbase.HTableDescriptor;
import org.apache.hadoop.hbase.TableName;
+import org.apache.hadoop.hbase.TableNotFoundException;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.hbase.classification.InterfaceStability;
import org.apache.hadoop.hbase.client.Admin;
import org.apache.hadoop.hbase.client.Connection;
import org.apache.hadoop.hbase.client.ConnectionFactory;
+import org.apache.hadoop.hbase.client.RegionLocator;
import org.apache.hadoop.hbase.replication.ReplicationException;
import org.apache.hadoop.hbase.replication.ReplicationFactory;
+import org.apache.hadoop.hbase.replication.ReplicationPeer;
import org.apache.hadoop.hbase.replication.ReplicationPeerConfig;
+import org.apache.hadoop.hbase.replication.ReplicationPeerZKImpl;
import org.apache.hadoop.hbase.replication.ReplicationPeers;
import org.apache.hadoop.hbase.replication.ReplicationQueuesClient;
+import org.apache.hadoop.hbase.util.Pair;
+import org.apache.hadoop.hbase.zookeeper.ZKUtil;
import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.zookeeper.KeeperException;
+import org.apache.zookeeper.data.Stat;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.collect.Lists;
@@ -501,4 +509,203 @@ public class ReplicationAdmin implements Closeable {
return replicationColFams;
}
+
+ /**
+ * Enable a table's replication switch.
+ * @param tableName name of the table
+ * @throws IOException if a remote or network exception occurs
+ */
+ public void enableTableRep(final TableName tableName) throws IOException {
+ if (tableName == null) {
+ throw new IllegalArgumentException("Table name cannot be null");
+ }
+ try (Admin admin = this.connection.getAdmin()) {
+ if (!admin.tableExists(tableName)) {
+ throw new TableNotFoundException("Table '" + tableName.getNameAsString()
+ + "' does not exists.");
+ }
+ }
+ byte[][] splits = getTableSplitRowKeys(tableName);
+ checkAndSyncTableDescToPeers(tableName, splits);
+ setTableRep(tableName, true);
+ }
+
+ /**
+ * Disable a table's replication switch.
+ * @param tableName name of the table
+ * @throws IOException if a remote or network exception occurs
+ */
+ public void disableTableRep(final TableName tableName) throws IOException {
+ if (tableName == null) {
+ throw new IllegalArgumentException("Table name is null");
+ }
+ try (Admin admin = this.connection.getAdmin()) {
+ if (!admin.tableExists(tableName)) {
+ throw new TableNotFoundException("Table '" + tableName.getNamespaceAsString()
+ + "' does not exists.");
+ }
+ }
+ setTableRep(tableName, false);
+ }
+
+ /**
+ * Get the split row keys of table
+ * @param tableName table name
+ * @return array of split row keys
+ * @throws IOException
+ */
+ private byte[][] getTableSplitRowKeys(TableName tableName) throws IOException {
+ try (RegionLocator locator = connection.getRegionLocator(tableName);) {
+ byte[][] startKeys = locator.getStartKeys();
+ if (startKeys.length == 1) {
+ return null;
+ }
+ byte[][] splits = new byte[startKeys.length - 1][];
+ for (int i = 1; i < startKeys.length; i++) {
+ splits[i - 1] = startKeys[i];
+ }
+ return splits;
+ }
+ }
+
+ /**
+ * Connect to peer and check the table descriptor on peer:
+ * <ol>
+ * <li>Create the same table on peer when not exist.</li>
+ * <li>Throw exception if the table exists on peer cluster but descriptors are not same.</li>
+ * </ol>
+ * @param tableName name of the table to sync to the peer
+ * @param splits table split keys
+ * @throws IOException
+ */
+ private void checkAndSyncTableDescToPeers(final TableName tableName, final byte[][] splits)
+ throws IOException {
+ List<ReplicationPeer> repPeers = listValidReplicationPeers();
+ if (repPeers == null || repPeers.size() <= 0) {
+ throw new IllegalArgumentException("Found no peer cluster for replication.");
+ }
+ for (ReplicationPeer repPeer : repPeers) {
+ Configuration peerConf = repPeer.getConfiguration();
+ HTableDescriptor htd = null;
+ try (Connection conn = ConnectionFactory.createConnection(peerConf);
+ Admin admin = this.connection.getAdmin();
+ Admin repHBaseAdmin = conn.getAdmin()) {
+ htd = admin.getTableDescriptor(tableName);
+ HTableDescriptor peerHtd = null;
+ if (!repHBaseAdmin.tableExists(tableName)) {
+ repHBaseAdmin.createTable(htd, splits);
+ } else {
+ peerHtd = repHBaseAdmin.getTableDescriptor(tableName);
+ if (peerHtd == null) {
+ throw new IllegalArgumentException("Failed to get table descriptor for table "
+ + tableName.getNameAsString() + " from peer cluster " + repPeer.getId());
+ } else if (!peerHtd.equals(htd)) {
+ throw new IllegalArgumentException("Table " + tableName.getNameAsString()
+ + " exists in peer cluster " + repPeer.getId()
+ + ", but the table descriptors are not same when comapred with source cluster."
+ + " Thus can not enable the table's replication switch.");
+ }
+ }
+ }
+ }
+ }
+
+ private List<ReplicationPeer> listValidReplicationPeers() {
+ Map<String, ReplicationPeerConfig> peers = listPeerConfigs();
+ if (peers == null || peers.size() <= 0) {
+ return null;
+ }
+ List<ReplicationPeer> validPeers = new ArrayList<ReplicationPeer>(peers.size());
+ for (Entry<String, ReplicationPeerConfig> peerEntry : peers.entrySet()) {
+ String peerId = peerEntry.getKey();
+ String clusterKey = peerEntry.getValue().getClusterKey();
+ Configuration peerConf = new Configuration(this.connection.getConfiguration());
+ Stat s = null;
+ try {
+ ZKUtil.applyClusterKeyToConf(peerConf, clusterKey);
+ Pair<ReplicationPeerConfig, Configuration> pair = this.replicationPeers.getPeerConf(peerId);
+ ReplicationPeer peer = new ReplicationPeerZKImpl(peerConf, peerId, pair.getFirst());
+ s =
+ zkw.getRecoverableZooKeeper().exists(peerConf.get(HConstants.ZOOKEEPER_ZNODE_PARENT),
+ null);
+ if (null == s) {
+ LOG.info(peerId + ' ' + clusterKey + " is invalid now.");
+ continue;
+ }
+ validPeers.add(peer);
+ } catch (ReplicationException e) {
+ LOG.warn("Failed to get valid replication peers. "
+ + "Error connecting to peer cluster with peerId=" + peerId);
+ LOG.debug("Failure details to get valid replication peers.", e);
+ continue;
+ } catch (KeeperException e) {
+ LOG.warn("Failed to get valid replication peers. KeeperException code="
+ + e.code().intValue());
+ LOG.debug("Failure details to get valid replication peers.", e);
+ continue;
+ } catch (InterruptedException e) {
+ LOG.warn("Failed to get valid replication peers due to InterruptedException.");
+ LOG.debug("Failure details to get valid replication peers.", e);
+ Thread.currentThread().interrupt();
+ continue;
+ } catch (IOException e) {
+ LOG.warn("Failed to get valid replication peers due to IOException.");
+ LOG.debug("Failure details to get valid replication peers.", e);
+ continue;
+ }
+ }
+ return validPeers;
+ }
+
+ /**
+ * Set the table's replication switch if the table's replication switch is already not set.
+ * @param tableName name of the table
+ * @param isRepEnabled is replication switch enable or disable
+ * @throws IOException if a remote or network exception occurs
+ */
+ private void setTableRep(final TableName tableName, boolean isRepEnabled) throws IOException {
+ Admin admin = null;
+ try {
+ admin = this.connection.getAdmin();
+ HTableDescriptor htd = admin.getTableDescriptor(tableName);
+ if (isTableRepEnabled(htd) ^ isRepEnabled) {
+ boolean isOnlineSchemaUpdateEnabled =
+ this.connection.getConfiguration()
+ .getBoolean("hbase.online.schema.update.enable", true);
+ if (!isOnlineSchemaUpdateEnabled) {
+ admin.disableTable(tableName);
+ }
+ for (HColumnDescriptor hcd : htd.getFamilies()) {
+ hcd.setScope(isRepEnabled ? HConstants.REPLICATION_SCOPE_GLOBAL
+ : HConstants.REPLICATION_SCOPE_LOCAL);
+ }
+ admin.modifyTable(tableName, htd);
+ if (!isOnlineSchemaUpdateEnabled) {
+ admin.enableTable(tableName);
+ }
+ }
+ } finally {
+ if (admin != null) {
+ try {
+ admin.close();
+ } catch (IOException e) {
+ LOG.warn("Failed to close admin connection.");
+ LOG.debug("Details on failure to close admin connection.", e);
+ }
+ }
+ }
+ }
+
+ /**
+ * @param htd table descriptor details for the table to check
+ * @return true if table's replication switch is enabled
+ */
+ private boolean isTableRepEnabled(HTableDescriptor htd) {
+ for (HColumnDescriptor hcd : htd.getFamilies()) {
+ if (hcd.getScope() != HConstants.REPLICATION_SCOPE_GLOBAL) {
+ return false;
+ }
+ }
+ return true;
+ }
}
http://git-wip-us.apache.org/repos/asf/hbase/blob/9a311303/hbase-server/src/test/java/org/apache/hadoop/hbase/client/replication/TestReplicationAdminWithClusters.java
----------------------------------------------------------------------
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/client/replication/TestReplicationAdminWithClusters.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/client/replication/TestReplicationAdminWithClusters.java
new file mode 100644
index 0000000..b5899b8
--- /dev/null
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/client/replication/TestReplicationAdminWithClusters.java
@@ -0,0 +1,163 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one or more contributor license
+ * agreements. See the NOTICE file distributed with this work for additional information regarding
+ * copyright ownership. The ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the License. You may obtain a
+ * copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable
+ * law or agreed to in writing, software distributed under the License is distributed on an "AS IS"
+ * BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License
+ * for the specific language governing permissions and limitations under the License.
+ */
+package org.apache.hadoop.hbase.client.replication;
+
+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 org.apache.hadoop.hbase.HColumnDescriptor;
+import org.apache.hadoop.hbase.HConstants;
+import org.apache.hadoop.hbase.HTableDescriptor;
+import org.apache.hadoop.hbase.TableName;
+import org.apache.hadoop.hbase.TableNotFoundException;
+import org.apache.hadoop.hbase.client.Admin;
+import org.apache.hadoop.hbase.client.Connection;
+import org.apache.hadoop.hbase.client.ConnectionFactory;
+import org.apache.hadoop.hbase.replication.TestReplicationBase;
+import org.apache.hadoop.hbase.testclassification.ClientTests;
+import org.apache.hadoop.hbase.testclassification.MediumTests;
+import org.junit.AfterClass;
+import org.junit.BeforeClass;
+import org.junit.Test;
+import org.junit.experimental.categories.Category;
+
+/**
+ * Unit testing of ReplicationAdmin with clusters
+ */
+@Category({ MediumTests.class, ClientTests.class })
+public class TestReplicationAdminWithClusters extends TestReplicationBase {
+
+ static Connection connection1;
+ static Connection connection2;
+ static Admin admin1;
+ static Admin admin2;
+
+ @BeforeClass
+ public static void setUpBeforeClass() throws Exception {
+ TestReplicationBase.setUpBeforeClass();
+ connection1 = ConnectionFactory.createConnection(conf1);
+ connection2 = ConnectionFactory.createConnection(conf2);
+ admin1 = connection1.getAdmin();
+ admin2 = connection2.getAdmin();
+ }
+
+ @AfterClass
+ public static void tearDownAfterClass() throws Exception {
+ admin1.close();
+ admin2.close();
+ connection1.close();
+ connection2.close();
+ TestReplicationBase.tearDownAfterClass();
+ }
+
+ @Test(timeout = 300000)
+ public void testEnableReplicationWhenSlaveClusterDoesntHaveTable() throws Exception {
+ admin2.disableTable(tableName);
+ admin2.deleteTable(tableName);
+ assertFalse(admin2.tableExists(tableName));
+ ReplicationAdmin adminExt = new ReplicationAdmin(conf1);
+ adminExt.enableTableRep(tableName);
+ assertTrue(admin2.tableExists(tableName));
+ }
+
+ @Test(timeout = 300000)
+ public void testEnableReplicationWhenReplicationNotEnabled() throws Exception {
+ HTableDescriptor table = admin1.getTableDescriptor(tableName);
+ for (HColumnDescriptor fam : table.getColumnFamilies()) {
+ fam.setScope(HConstants.REPLICATION_SCOPE_LOCAL);
+ }
+ admin1.disableTable(tableName);
+ admin1.modifyTable(tableName, table);
+ admin1.enableTable(tableName);
+
+ admin2.disableTable(tableName);
+ admin2.modifyTable(tableName, table);
+ admin2.enableTable(tableName);
+
+ ReplicationAdmin adminExt = new ReplicationAdmin(conf1);
+ adminExt.enableTableRep(tableName);
+ table = admin1.getTableDescriptor(tableName);
+ for (HColumnDescriptor fam : table.getColumnFamilies()) {
+ assertEquals(fam.getScope(), HConstants.REPLICATION_SCOPE_GLOBAL);
+ }
+ }
+
+ @Test(timeout = 300000)
+ public void testEnableReplicationWhenTableDescriptorIsNotSameInClusters() throws Exception {
+ HTableDescriptor table = admin2.getTableDescriptor(tableName);
+ HColumnDescriptor f = new HColumnDescriptor("newFamily");
+ table.addFamily(f);
+ admin2.disableTable(tableName);
+ admin2.modifyTable(tableName, table);
+ admin2.enableTable(tableName);
+
+ ReplicationAdmin adminExt = new ReplicationAdmin(conf1);
+ try {
+ adminExt.enableTableRep(tableName);
+ fail("Exception should be thrown if table descriptors in the clusters are not same.");
+ } catch (RuntimeException ignored) {
+
+ }
+ admin1.disableTable(tableName);
+ admin1.modifyTable(tableName, table);
+ admin1.enableTable(tableName);
+ adminExt.enableTableRep(tableName);
+ table = admin1.getTableDescriptor(tableName);
+ for (HColumnDescriptor fam : table.getColumnFamilies()) {
+ assertEquals(fam.getScope(), HConstants.REPLICATION_SCOPE_GLOBAL);
+ }
+ }
+
+ @Test(timeout = 300000)
+ public void testDisableAndEnableReplication() throws Exception {
+ ReplicationAdmin adminExt = new ReplicationAdmin(conf1);
+ adminExt.disableTableRep(tableName);
+ HTableDescriptor table = admin1.getTableDescriptor(tableName);
+ for (HColumnDescriptor fam : table.getColumnFamilies()) {
+ assertEquals(fam.getScope(), HConstants.REPLICATION_SCOPE_LOCAL);
+ }
+ table = admin2.getTableDescriptor(tableName);
+ for (HColumnDescriptor fam : table.getColumnFamilies()) {
+ assertEquals(fam.getScope(), HConstants.REPLICATION_SCOPE_LOCAL);
+ }
+ adminExt.enableTableRep(tableName);
+ table = admin1.getTableDescriptor(tableName);
+ for (HColumnDescriptor fam : table.getColumnFamilies()) {
+ assertEquals(fam.getScope(), HConstants.REPLICATION_SCOPE_GLOBAL);
+ }
+ }
+
+ @Test(timeout = 300000, expected = TableNotFoundException.class)
+ public void testDisableReplicationForNonExistingTable() throws Exception {
+ ReplicationAdmin adminExt = new ReplicationAdmin(conf1);
+ adminExt.disableTableRep(TableName.valueOf("nonExistingTable"));
+ }
+
+ @Test(timeout = 300000, expected = TableNotFoundException.class)
+ public void testEnableReplicationForNonExistingTable() throws Exception {
+ ReplicationAdmin adminExt = new ReplicationAdmin(conf1);
+ adminExt.enableTableRep(TableName.valueOf("nonExistingTable"));
+ }
+
+ @Test(timeout = 300000, expected = IllegalArgumentException.class)
+ public void testDisableReplicationWhenTableNameAsNull() throws Exception {
+ ReplicationAdmin adminExt = new ReplicationAdmin(conf1);
+ adminExt.disableTableRep(null);
+ }
+
+ @Test(timeout = 300000, expected = IllegalArgumentException.class)
+ public void testEnableReplicationWhenTableNameAsNull() throws Exception {
+ ReplicationAdmin adminExt = new ReplicationAdmin(conf1);
+ adminExt.enableTableRep(null);
+ }
+}
http://git-wip-us.apache.org/repos/asf/hbase/blob/9a311303/hbase-shell/src/main/ruby/hbase/replication_admin.rb
----------------------------------------------------------------------
diff --git a/hbase-shell/src/main/ruby/hbase/replication_admin.rb b/hbase-shell/src/main/ruby/hbase/replication_admin.rb
index 2d0845f..b2ca8e1 100644
--- a/hbase-shell/src/main/ruby/hbase/replication_admin.rb
+++ b/hbase-shell/src/main/ruby/hbase/replication_admin.rb
@@ -23,6 +23,7 @@ java_import org.apache.hadoop.hbase.client.replication.ReplicationAdmin
java_import org.apache.hadoop.hbase.replication.ReplicationPeerConfig
java_import org.apache.hadoop.hbase.util.Bytes
java_import org.apache.hadoop.hbase.zookeeper.ZKUtil
+java_import org.apache.hadoop.hbase.TableName
# Wrapper for org.apache.hadoop.hbase.client.replication.ReplicationAdmin
@@ -157,5 +158,17 @@ module Hbase
def remove_peer_tableCFs(id, tableCFs)
@replication_admin.removePeerTableCFs(id, tableCFs)
end
+ #----------------------------------------------------------------------------------------------
+ # Enables a table's replication switch
+ def enable_tablerep(table_name)
+ tableName = TableName.valueOf(table_name)
+ @replication_admin.enableTableRep(tableName)
+ end
+ #----------------------------------------------------------------------------------------------
+ # Disables a table's replication switch
+ def disable_tablerep(table_name)
+ tableName = TableName.valueOf(table_name)
+ @replication_admin.disableTableRep(tableName)
+ end
end
end
http://git-wip-us.apache.org/repos/asf/hbase/blob/9a311303/hbase-shell/src/main/ruby/shell.rb
----------------------------------------------------------------------
diff --git a/hbase-shell/src/main/ruby/shell.rb b/hbase-shell/src/main/ruby/shell.rb
index 5db2776..893079d 100644
--- a/hbase-shell/src/main/ruby/shell.rb
+++ b/hbase-shell/src/main/ruby/shell.rb
@@ -349,6 +349,8 @@ Shell.load_command_group(
list_replicated_tables
append_peer_tableCFs
remove_peer_tableCFs
+ enable_table_replication
+ disable_table_replication
]
)
http://git-wip-us.apache.org/repos/asf/hbase/blob/9a311303/hbase-shell/src/main/ruby/shell/commands/disable_table_replication.rb
----------------------------------------------------------------------
diff --git a/hbase-shell/src/main/ruby/shell/commands/disable_table_replication.rb b/hbase-shell/src/main/ruby/shell/commands/disable_table_replication.rb
new file mode 100644
index 0000000..4c46fea
--- /dev/null
+++ b/hbase-shell/src/main/ruby/shell/commands/disable_table_replication.rb
@@ -0,0 +1,42 @@
+#
+# Copyright 2010 The Apache Software Foundation
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements. See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership. The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License. You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+module Shell
+ module Commands
+ class DisableTableReplication< Command
+ def help
+ return <<-EOF
+Disable a table's replication switch.
+
+Examples:
+
+ hbase> disable_table_replication 'table_name'
+EOF
+ end
+
+ def command(table_name)
+ format_simple_command do
+ replication_admin.disable_tablerep(table_name)
+ end
+ puts "The replication swith of table '#{table_name}' successfully disabled"
+ end
+ end
+ end
+end
http://git-wip-us.apache.org/repos/asf/hbase/blob/9a311303/hbase-shell/src/main/ruby/shell/commands/enable_table_replication.rb
----------------------------------------------------------------------
diff --git a/hbase-shell/src/main/ruby/shell/commands/enable_table_replication.rb b/hbase-shell/src/main/ruby/shell/commands/enable_table_replication.rb
new file mode 100644
index 0000000..5d57f03
--- /dev/null
+++ b/hbase-shell/src/main/ruby/shell/commands/enable_table_replication.rb
@@ -0,0 +1,42 @@
+#
+# Copyright 2010 The Apache Software Foundation
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements. See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership. The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License. You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+module Shell
+ module Commands
+ class EnableTableReplication< Command
+ def help
+ return <<-EOF
+Enable a table's replication switch.
+
+Examples:
+
+ hbase> enable_table_replication 'table_name'
+EOF
+ end
+
+ def command(table_name)
+ format_simple_command do
+ replication_admin.enable_tablerep(table_name)
+ end
+ puts "The replication swith of table '#{table_name}' successfully enabled"
+ end
+ end
+ end
+end