/**
    * 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;
  
  import java.util.List;
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.hadoop.conf.Configuration;
  import org.apache.hadoop.fs.FileSystem;
  import org.apache.hadoop.fs.Path;
  import org.apache.hadoop.hbase.HBaseTestingUtility;
  import org.apache.hadoop.hbase.HColumnDescriptor;
  import org.apache.hadoop.hbase.HConstants;
  import org.apache.hadoop.hbase.HRegionInfo;
  import org.apache.hadoop.hbase.HTableDescriptor;
  import org.apache.hadoop.hbase.TableName;
  import org.apache.hadoop.hbase.master.snapshot.SnapshotManager;
  import org.apache.hadoop.hbase.regionserver.ConstantSizeRegionSplitPolicy;
  import org.apache.hadoop.hbase.snapshot.SnapshotTestingUtils;
  import org.apache.hadoop.hbase.testclassification.ClientTests;
  import org.apache.hadoop.hbase.testclassification.MediumTests;
  import org.apache.hadoop.hbase.util.Bytes;
  import org.apache.hadoop.hbase.util.Threads;
  import org.junit.AfterClass;
  import org.junit.Assert;
  import org.junit.Before;
  import org.junit.BeforeClass;
  import org.junit.Rule;
  import org.junit.Test;
  import org.junit.experimental.categories.Category;
  import org.junit.rules.TestName;
  import org.junit.rules.Timeout;
  
  /**
   * Test to verify that the cloned table is independent of the table from which it was cloned
   */
  @Category({MediumTests.class, ClientTests.class})
  public class TestSnapshotCloneIndependence {
    private static final Log LOG = LogFactory.getLog(TestSnapshotCloneIndependence.class);
  
    @Rule
    public Timeout globalTimeout = Timeout.seconds(60);
  
    @Rule
    public TestName testName = new TestName();
  
    protected static final HBaseTestingUtility UTIL = new HBaseTestingUtility();
  
    protected static final int NUM_RS = 2;
    private static final String STRING_TABLE_NAME = "test";
    private static final String TEST_FAM_STR = "fam";
    protected static final byte[] TEST_FAM = Bytes.toBytes(TEST_FAM_STR);
    private static final int CLEANER_INTERVAL = 100;
  
    private FileSystem fs;
    private Path rootDir;
    private Admin admin;
    private TableName originalTableName;
    private Table originalTable;
    private TableName cloneTableName;
    private int countOriginalTable;
    String snapshotNameAsString;
    byte[] snapshotName;
  
    /**
     * Setup the config for the cluster and start it
     */
    @BeforeClass
    public static void setupCluster() throws Exception {
      setupConf(UTIL.getConfiguration());
      UTIL.startMiniCluster(NUM_RS);
    }
  
    static void setupConf(Configuration conf) {
      // Up the handlers; this test needs more than usual.
      conf.setInt(HConstants.REGION_SERVER_HIGH_PRIORITY_HANDLER_COUNT, 15);
      // enable snapshot support
      conf.setBoolean(SnapshotManager.HBASE_SNAPSHOT_ENABLED, true);
      // disable the ui
      conf.setInt("hbase.regionsever.info.port", -1);
      conf.setInt("hbase.master.info.port", -1);
      // change the flush size to a small amount, regulating number of store files
      conf.setInt("hbase.hregion.memstore.flush.size", 25000);
     // so make sure we get a compaction when doing a load, but keep around
     // some files in the store
     conf.setInt("hbase.hstore.compaction.min", 10);
     conf.setInt("hbase.hstore.compactionThreshold", 10);
     // block writes if we get to 12 store files
     conf.setInt("hbase.hstore.blockingStoreFiles", 12);
     conf.setInt("hbase.regionserver.msginterval", 100);
     conf.setBoolean("hbase.master.enabletable.roundrobin", true);
     // Avoid potentially aggressive splitting which would cause snapshot to fail
     conf.set(HConstants.HBASE_REGION_SPLIT_POLICY_KEY,
         ConstantSizeRegionSplitPolicy.class.getName());
     // Execute cleaner frequently to induce failures
     conf.setInt("hbase.master.cleaner.interval", CLEANER_INTERVAL);
     conf.setInt("hbase.master.hfilecleaner.plugins.snapshot.period", CLEANER_INTERVAL);
     // Effectively disable TimeToLiveHFileCleaner. Don't want to fully disable it because that
     // will even trigger races between creating the directory containing back references and
     // the back reference itself.
     conf.setInt("hbase.master.hfilecleaner.ttl", CLEANER_INTERVAL);
   }
 
   @Before
   public void setup() throws Exception {
     fs = UTIL.getHBaseCluster().getMaster().getMasterFileSystem().getFileSystem();
     rootDir = UTIL.getHBaseCluster().getMaster().getMasterFileSystem().getRootDir();
 
     admin = UTIL.getHBaseAdmin();
     originalTableName = TableName.valueOf("test" + testName.getMethodName());
     cloneTableName = TableName.valueOf("test-clone-" + originalTableName);
     snapshotNameAsString = "snapshot_" + originalTableName;
     snapshotName = Bytes.toBytes(snapshotNameAsString);
 
     originalTable = createTable(originalTableName, TEST_FAM);
     loadData(originalTable, TEST_FAM);
     countOriginalTable = countRows(originalTable);
     System.out.println("Original table has: " + countOriginalTable + " rows");
   }
 
   private void tearDown() throws Exception {
     UTIL.deleteTable(originalTableName);
     UTIL.deleteTable(cloneTableName);
     SnapshotTestingUtils.deleteAllSnapshots(UTIL.getHBaseAdmin());
     SnapshotTestingUtils.deleteArchiveDirectory(UTIL);
   }
 
   @AfterClass
   public static void cleanupTest() throws Exception {
     try {
       UTIL.shutdownMiniCluster();
     } catch (Exception e) {
       LOG.warn("failure shutting down cluster", e);
     }
   }
 
   /**
    * Verify that adding data to the cloned table will not affect the original, and vice-versa when
    * it is taken as an online snapshot.
    */
   @Test(timeout = 30000)
   public void testOnlineSnapshotAppendIndependent() throws Exception {
     createAndCloneSnapshot(true);
     runTestSnapshotAppendIndependent();
     tearDown();
   }
 
   /**
    * Verify that adding data to the cloned table will not affect the original, and vice-versa when
    * it is taken as an offline snapshot.
    */
   @Test(timeout = 30000)
   public void testOfflineSnapshotAppendIndependent() throws Exception {
     createAndCloneSnapshot(false);
     runTestSnapshotAppendIndependent();
     tearDown();
   }
 
   /**
    * Verify that adding metadata to the cloned table will not affect the original, and vice-versa
    * when it is taken as an online snapshot.
    */
   @Test(timeout = 30000)
   public void testOnlineSnapshotMetadataChangesIndependent() throws Exception {
     createAndCloneSnapshot(true);
     runTestSnapshotMetadataChangesIndependent();
     tearDown();
   }
 
   /**
    * Verify that adding netadata to the cloned table will not affect the original, and vice-versa
    * when is taken as an online snapshot.
    */
   @Test(timeout = 30000)
   public void testOfflineSnapshotMetadataChangesIndependent() throws Exception {
     createAndCloneSnapshot(false);
     runTestSnapshotMetadataChangesIndependent();
     tearDown();
   }
 
   /**
    * Verify that region operations, in this case splitting a region, are independent between the
    * cloned table and the original.
    */
   @Test(timeout = 30000)
   public void testOfflineSnapshotRegionOperationsIndependent() throws Exception {
     createAndCloneSnapshot(false);
     runTestRegionOperationsIndependent();
     tearDown();
   }
 
   /**
    * Verify that region operations, in this case splitting a region, are independent between the
    * cloned table and the original.
    */
   @Test(timeout = 30000)
   public void testOnlineSnapshotRegionOperationsIndependent() throws Exception {
     createAndCloneSnapshot(true);
     runTestRegionOperationsIndependent();
     tearDown();
   }
 
   @Test(timeout = 30000)
   public void testOfflineSnapshotDeleteIndependent() throws Exception {
     createAndCloneSnapshot(false);
     runTestSnapshotDeleteIndependent();
     tearDown();
   }
 
   @Test(timeout = 30000)
   public void testOnlineSnapshotDeleteIndependent() throws Exception {
     createAndCloneSnapshot(true);
     runTestSnapshotDeleteIndependent();
     tearDown();
   }
 
   private static void waitOnSplit(Connection c, final Table t, int originalCount) throws Exception {
     for (int i = 0; i < 200; i++) {
       Threads.sleepWithoutInterrupt(500);
       try (RegionLocator locator = c.getRegionLocator(t.getName())) {
         if (locator.getAllRegionLocations().size() > originalCount) {
           return;
         }
       }
     }
     throw new Exception("Split did not increase the number of regions");
   }
 
   /**
    * Takes the snapshot of originalTable and clones the snapshot to another tables.
    * If {@code online} is false, the original table is disabled during taking snapshot, so also
    * enables it again.
    * @param online - Whether the table is online or not during the snapshot
    */
   private void createAndCloneSnapshot(boolean online) throws Exception {
     SnapshotTestingUtils.createSnapshotAndValidate(admin, originalTableName, TEST_FAM_STR,
       snapshotNameAsString, rootDir, fs, online);
 
     // If offline, enable the table disabled by snapshot testing util.
     if (!online) {
       admin.enableTable(originalTableName);
       UTIL.waitTableAvailable(originalTableName);
     }
 
     admin.cloneSnapshot(snapshotName, cloneTableName);
     UTIL.waitUntilAllRegionsAssigned(cloneTableName);
   }
 
   /**
    * Verify that adding data to original table or clone table doesn't affect other table.
    */
   private void runTestSnapshotAppendIndependent() throws Exception {
     try (Table clonedTable = UTIL.getConnection().getTable(cloneTableName)) {
       final int clonedTableRowCount = countRows(clonedTable);
 
       Assert.assertEquals(
         "The line counts of original and cloned tables do not match after clone. ",
         countOriginalTable, clonedTableRowCount);
 
       // Attempt to add data to the test
       Put p = new Put(Bytes.toBytes("new-row-" + System.currentTimeMillis()));
       p.addColumn(TEST_FAM, Bytes.toBytes("someQualifier"), Bytes.toBytes("someString"));
       originalTable.put(p);
 
       // Verify that the new row is not in the restored table
       Assert.assertEquals("The row count of the original table was not modified by the put",
         countOriginalTable + 1, countRows(originalTable));
       Assert.assertEquals(
         "The row count of the cloned table changed as a result of addition to the original",
         clonedTableRowCount, countRows(clonedTable));
 
       Put p2 = new Put(Bytes.toBytes("new-row-" + System.currentTimeMillis()));
       p2.addColumn(TEST_FAM, Bytes.toBytes("someQualifier"), Bytes.toBytes("someString"));
       clonedTable.put(p2);
 
       // Verify that the row is not added to the original table.
       Assert.assertEquals(
         "The row count of the original table was modified by the put to the clone",
         countOriginalTable + 1, countRows(originalTable));
       Assert.assertEquals("The row count of the cloned table was not modified by the put",
         clonedTableRowCount + 1, countRows(clonedTable));
     }
   }
 
   /**
    * Do a split, and verify that this only affects one table
    */
   private void runTestRegionOperationsIndependent() throws Exception {
     // Verify that region information is the same pre-split
     ((ClusterConnection) UTIL.getConnection()).clearRegionCache();
     List<HRegionInfo> originalTableHRegions = admin.getTableRegions(originalTableName);
 
     final int originalRegionCount = originalTableHRegions.size();
     final int cloneTableRegionCount = admin.getTableRegions(cloneTableName).size();
     Assert.assertEquals(
       "The number of regions in the cloned table is different than in the original table.",
       originalRegionCount, cloneTableRegionCount);
 
     // Split a region on the parent table
     admin.splitRegion(originalTableHRegions.get(0).getRegionName());
     waitOnSplit(UTIL.getConnection(), originalTable, originalRegionCount);
 
     // Verify that the cloned table region is not split
     final int cloneTableRegionCount2 = admin.getTableRegions(cloneTableName).size();
     Assert.assertEquals(
       "The number of regions in the cloned table changed though none of its regions were split.",
       cloneTableRegionCount, cloneTableRegionCount2);
   }
 
   /**
    * Add metadata, and verify that this only affects one table
    */
   private void runTestSnapshotMetadataChangesIndependent() throws Exception {
     // Add a new column family to the original table
     byte[] TEST_FAM_2 = Bytes.toBytes("fam2");
     HColumnDescriptor hcd = new HColumnDescriptor(TEST_FAM_2);
 
     admin.disableTable(originalTableName);
     admin.addColumn(originalTableName, hcd);
 
     // Verify that it is not in the snapshot
     admin.enableTable(originalTableName);
     UTIL.waitTableAvailable(originalTableName);
 
     // get a description of the cloned table
     // get a list of its families
     // assert that the family is there
     HTableDescriptor originalTableDescriptor = originalTable.getTableDescriptor();
     HTableDescriptor clonedTableDescriptor = admin.getTableDescriptor(cloneTableName);
 
     Assert.assertTrue("The original family was not found. There is something wrong. ",
       originalTableDescriptor.hasFamily(TEST_FAM));
     Assert.assertTrue("The original family was not found in the clone. There is something wrong. ",
       clonedTableDescriptor.hasFamily(TEST_FAM));
 
     Assert.assertTrue("The new family was not found. ",
       originalTableDescriptor.hasFamily(TEST_FAM_2));
     Assert.assertTrue("The new family was not found. ",
       !clonedTableDescriptor.hasFamily(TEST_FAM_2));
   }
 
   /**
    * Verify that deleting the snapshot does not affect either table.
    */
   private void runTestSnapshotDeleteIndependent() throws Exception {
     // Ensure the original table does not reference the HFiles anymore
     admin.majorCompact(originalTableName);
 
     // Deleting the snapshot used to break the cloned table by deleting in-use HFiles
     admin.deleteSnapshot(snapshotName);
 
     // Wait for cleaner run and DFS heartbeats so that anything that is deletable is fully deleted
     do {
       Thread.sleep(5000);
     } while (!admin.listSnapshots(snapshotNameAsString).isEmpty());
 
     try (Table original = UTIL.getConnection().getTable(originalTableName)) {
       try (Table clonedTable = UTIL.getConnection().getTable(cloneTableName)) {
         // Verify that all regions of both tables are readable
         final int origTableRowCount = countRows(original);
         final int clonedTableRowCount = countRows(clonedTable);
         Assert.assertEquals(origTableRowCount, clonedTableRowCount);
       }
     }
   }
 
   protected Table createTable(final TableName table, byte[] family) throws Exception {
    Table t = UTIL.createTable(table, family);
     // Wait for everything to be ready with the table
     UTIL.waitUntilAllRegionsAssigned(table);
 
     // At this point the table should be good to go.
     return t;
   }
 
   public void loadData(final Table table, byte[]... families) throws Exception {
     UTIL.loadTable(originalTable, TEST_FAM);
   }
 
   protected int countRows(final Table table, final byte[]... families) throws Exception {
     return UTIL.countRows(table, families);
   }
 }