/*
 * 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.replication;

import static org.apache.hadoop.hbase.HBaseTestingUtil.countRows;
import static org.apache.hadoop.hbase.replication.TestReplicationBase.NB_RETRIES;
import static org.apache.hadoop.hbase.replication.TestReplicationBase.NB_ROWS_IN_BATCH;
import static org.apache.hadoop.hbase.replication.TestReplicationBase.SLEEP_TIME;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;

import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;
import org.apache.hadoop.fs.FileAlreadyExistsException;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hbase.HBaseClassTestRule;
import org.apache.hadoop.hbase.ServerName;
import org.apache.hadoop.hbase.client.Delete;
import org.apache.hadoop.hbase.client.Put;
import org.apache.hadoop.hbase.replication.regionserver.ReplicationSyncUp;
import org.apache.hadoop.hbase.testclassification.LargeTests;
import org.apache.hadoop.hbase.testclassification.ReplicationTests;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.hbase.util.CommonFSUtils;
import org.junit.ClassRule;
import org.junit.Test;
import org.junit.experimental.categories.Category;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

@Category({ ReplicationTests.class, LargeTests.class })
public class TestReplicationSyncUpTool extends TestReplicationSyncUpToolBase {

  @ClassRule
  public static final HBaseClassTestRule CLASS_RULE =
    HBaseClassTestRule.forClass(TestReplicationSyncUpTool.class);

  private static final Logger LOG = LoggerFactory.getLogger(TestReplicationSyncUpTool.class);

  /**
   * Add a row to a table in each cluster, check it's replicated, delete it, check's gone Also check
   * the puts and deletes are not replicated back to the originating cluster.
   */
  @Test
  public void testSyncUpTool() throws Exception {
    // Set up Replication: on Master and one Slave
    // Table: t1_syncup and t2_syncup
    // columnfamily:
    // 'cf1' : replicated
    // 'norep': not replicated
    setupReplication();

    //
    // at Master:
    // t1_syncup: put 100 rows into cf1, and 1 rows into norep
    // t2_syncup: put 200 rows into cf1, and 1 rows into norep
    //
    // verify correctly replicated to slave
    putAndReplicateRows();

    // Verify delete works
    //
    // step 1: stop hbase on Slave
    //
    // step 2: at Master:
    // t1_syncup: delete 50 rows from cf1
    // t2_syncup: delete 100 rows from cf1
    // no change on 'norep'
    //
    // step 3: stop hbase on master, restart hbase on Slave
    //
    // step 4: verify Slave still have the rows before delete
    // t1_syncup: 100 rows from cf1
    // t2_syncup: 200 rows from cf1
    //
    // step 5: run syncup tool on Master
    //
    // step 6: verify that delete show up on Slave
    // t1_syncup: 50 rows from cf1
    // t2_syncup: 100 rows from cf1
    //
    // verify correctly replicated to Slave
    mimicSyncUpAfterDelete();

    // Verify put works
    //
    // step 1: stop hbase on Slave
    //
    // step 2: at Master:
    // t1_syncup: put 100 rows from cf1
    // t2_syncup: put 200 rows from cf1
    // and put another row on 'norep'
    // ATTN:
    // put to 'cf1' will overwrite existing rows, so end count will be 100 and 200 respectively
    // put to 'norep' will add a new row.
    //
    // step 3: stop hbase on master, restart hbase on Slave
    //
    // step 4: verify Slave still has the rows before put
    // t1_syncup: 50 rows from cf1
    // t2_syncup: 100 rows from cf1
    //
    // step 5: run syncup tool on Master
    //
    // step 6: verify that put show up on Slave and 'norep' does not
    // t1_syncup: 100 rows from cf1
    // t2_syncup: 200 rows from cf1
    //
    // verify correctly replicated to Slave
    mimicSyncUpAfterPut();
  }

  private void putAndReplicateRows() throws Exception {
    LOG.debug("putAndReplicateRows");
    // add rows to Master cluster,
    Put p;

    // 100 + 1 row to t1_syncup
    for (int i = 0; i < NB_ROWS_IN_BATCH; i++) {
      p = new Put(Bytes.toBytes("row" + i));
      p.addColumn(FAMILY, QUALIFIER, Bytes.toBytes("val" + i));
      ht1Source.put(p);
    }
    p = new Put(Bytes.toBytes("row" + 9999));
    p.addColumn(NO_REP_FAMILY, QUALIFIER, Bytes.toBytes("val" + 9999));
    ht1Source.put(p);

    // 200 + 1 row to t2_syncup
    for (int i = 0; i < NB_ROWS_IN_BATCH * 2; i++) {
      p = new Put(Bytes.toBytes("row" + i));
      p.addColumn(FAMILY, QUALIFIER, Bytes.toBytes("val" + i));
      ht2Source.put(p);
    }
    p = new Put(Bytes.toBytes("row" + 9999));
    p.addColumn(NO_REP_FAMILY, QUALIFIER, Bytes.toBytes("val" + 9999));
    ht2Source.put(p);

    // ensure replication completed
    Thread.sleep(SLEEP_TIME);
    int rowCountHt1Source = countRows(ht1Source);
    for (int i = 0; i < NB_RETRIES; i++) {
      int rowCountHt1TargetAtPeer1 = countRows(ht1TargetAtPeer1);
      if (i == NB_RETRIES - 1) {
        assertEquals("t1_syncup has 101 rows on source, and 100 on slave1", rowCountHt1Source - 1,
          rowCountHt1TargetAtPeer1);
      }
      if (rowCountHt1Source - 1 == rowCountHt1TargetAtPeer1) {
        break;
      }
      Thread.sleep(SLEEP_TIME);
    }

    int rowCountHt2Source = countRows(ht2Source);
    for (int i = 0; i < NB_RETRIES; i++) {
      int rowCountHt2TargetAtPeer1 = countRows(ht2TargetAtPeer1);
      if (i == NB_RETRIES - 1) {
        assertEquals("t2_syncup has 201 rows on source, and 200 on slave1", rowCountHt2Source - 1,
          rowCountHt2TargetAtPeer1);
      }
      if (rowCountHt2Source - 1 == rowCountHt2TargetAtPeer1) {
        break;
      }
      Thread.sleep(SLEEP_TIME);
    }
  }

  private void mimicSyncUpAfterDelete() throws Exception {
    LOG.debug("mimicSyncUpAfterDelete");
    shutDownTargetHBaseCluster();

    List<Delete> list = new ArrayList<>();
    // delete half of the rows
    for (int i = 0; i < NB_ROWS_IN_BATCH / 2; i++) {
      String rowKey = "row" + i;
      Delete del = new Delete(Bytes.toBytes(rowKey));
      list.add(del);
    }
    ht1Source.delete(list);

    for (int i = 0; i < NB_ROWS_IN_BATCH; i++) {
      String rowKey = "row" + i;
      Delete del = new Delete(Bytes.toBytes(rowKey));
      list.add(del);
    }
    ht2Source.delete(list);

    int rowCount_ht1Source = countRows(ht1Source);
    assertEquals("t1_syncup has 51 rows on source, after remove 50 of the replicated colfam", 51,
      rowCount_ht1Source);

    int rowCount_ht2Source = countRows(ht2Source);
    assertEquals("t2_syncup has 101 rows on source, after remove 100 of the replicated colfam", 101,
      rowCount_ht2Source);
    List<ServerName> sourceRses = UTIL1.getHBaseCluster().getRegionServerThreads().stream()
      .map(rst -> rst.getRegionServer().getServerName()).collect(Collectors.toList());
    shutDownSourceHBaseCluster();
    restartTargetHBaseCluster(1);

    Thread.sleep(SLEEP_TIME);

    // before sync up
    int rowCountHt1TargetAtPeer1 = countRows(ht1TargetAtPeer1);
    int rowCountHt2TargetAtPeer1 = countRows(ht2TargetAtPeer1);
    assertEquals("@Peer1 t1_syncup should still have 100 rows", 100, rowCountHt1TargetAtPeer1);
    assertEquals("@Peer1 t2_syncup should still have 200 rows", 200, rowCountHt2TargetAtPeer1);

    syncUp(UTIL1);

    // After sync up
    rowCountHt1TargetAtPeer1 = countRows(ht1TargetAtPeer1);
    rowCountHt2TargetAtPeer1 = countRows(ht2TargetAtPeer1);
    assertEquals("@Peer1 t1_syncup should be sync up and have 50 rows", 50,
      rowCountHt1TargetAtPeer1);
    assertEquals("@Peer1 t2_syncup should be sync up and have 100 rows", 100,
      rowCountHt2TargetAtPeer1);

    // check we have recorded the dead region servers and also have an info file
    Path rootDir = CommonFSUtils.getRootDir(UTIL1.getConfiguration());
    Path syncUpInfoDir = new Path(rootDir, ReplicationSyncUp.INFO_DIR);
    FileSystem fs = UTIL1.getTestFileSystem();
    for (ServerName sn : sourceRses) {
      assertTrue(fs.exists(new Path(syncUpInfoDir, sn.getServerName())));
    }
    assertTrue(fs.exists(new Path(syncUpInfoDir, ReplicationSyncUp.INFO_FILE)));
    assertEquals(sourceRses.size() + 1, fs.listStatus(syncUpInfoDir).length);

    restartSourceHBaseCluster(1);
    // should finally removed all the records after restart
    UTIL1.waitFor(60000, () -> fs.listStatus(syncUpInfoDir).length == 0);
  }

  private void mimicSyncUpAfterPut() throws Exception {
    LOG.debug("mimicSyncUpAfterPut");
    shutDownTargetHBaseCluster();

    Put p;
    // another 100 + 1 row to t1_syncup
    // we should see 100 + 2 rows now
    for (int i = 0; i < NB_ROWS_IN_BATCH; i++) {
      p = new Put(Bytes.toBytes("row" + i));
      p.addColumn(FAMILY, QUALIFIER, Bytes.toBytes("val" + i));
      ht1Source.put(p);
    }
    p = new Put(Bytes.toBytes("row" + 9998));
    p.addColumn(NO_REP_FAMILY, QUALIFIER, Bytes.toBytes("val" + 9998));
    ht1Source.put(p);

    // another 200 + 1 row to t1_syncup
    // we should see 200 + 2 rows now
    for (int i = 0; i < NB_ROWS_IN_BATCH * 2; i++) {
      p = new Put(Bytes.toBytes("row" + i));
      p.addColumn(FAMILY, QUALIFIER, Bytes.toBytes("val" + i));
      ht2Source.put(p);
    }
    p = new Put(Bytes.toBytes("row" + 9998));
    p.addColumn(NO_REP_FAMILY, QUALIFIER, Bytes.toBytes("val" + 9998));
    ht2Source.put(p);

    int rowCount_ht1Source = countRows(ht1Source);
    assertEquals("t1_syncup has 102 rows on source", 102, rowCount_ht1Source);
    int rowCount_ht2Source = countRows(ht2Source);
    assertEquals("t2_syncup has 202 rows on source", 202, rowCount_ht2Source);

    shutDownSourceHBaseCluster();
    restartTargetHBaseCluster(1);

    Thread.sleep(SLEEP_TIME);

    // before sync up
    int rowCountHt1TargetAtPeer1 = countRows(ht1TargetAtPeer1);
    int rowCountHt2TargetAtPeer1 = countRows(ht2TargetAtPeer1);
    assertEquals("@Peer1 t1_syncup should be NOT sync up and have 50 rows", 50,
      rowCountHt1TargetAtPeer1);
    assertEquals("@Peer1 t2_syncup should be NOT sync up and have 100 rows", 100,
      rowCountHt2TargetAtPeer1);

    syncUp(UTIL1);

    // after sync up
    rowCountHt1TargetAtPeer1 = countRows(ht1TargetAtPeer1);
    rowCountHt2TargetAtPeer1 = countRows(ht2TargetAtPeer1);
    assertEquals("@Peer1 t1_syncup should be sync up and have 100 rows", 100,
      rowCountHt1TargetAtPeer1);
    assertEquals("@Peer1 t2_syncup should be sync up and have 200 rows", 200,
      rowCountHt2TargetAtPeer1);
  }

  /**
   * test "start a new ReplicationSyncUp after the previous failed". See HBASE-27623 for details.
   */
  @Test
  public void testStartANewSyncUpToolAfterFailed() throws Exception {
    // Start syncUpTool for the first time with non-force mode,
    // let's assume that this will fail in sync data,
    // this does not affect our test results
    syncUp(UTIL1);
    Path rootDir = CommonFSUtils.getRootDir(UTIL1.getConfiguration());
    Path syncUpInfoDir = new Path(rootDir, ReplicationSyncUp.INFO_DIR);
    Path replicationInfoPath = new Path(syncUpInfoDir, ReplicationSyncUp.INFO_FILE);
    FileSystem fs = UTIL1.getTestFileSystem();
    assertTrue(fs.exists(replicationInfoPath));
    FileStatus fileStatus1 = fs.getFileStatus(replicationInfoPath);

    // Start syncUpTool for the second time with non-force mode,
    // startup will fail because replication info file already exists
    try {
      syncUp(UTIL1);
    } catch (Exception e) {
      assertTrue("e should be a FileAlreadyExistsException",
        (e instanceof FileAlreadyExistsException));
    }
    FileStatus fileStatus2 = fs.getFileStatus(replicationInfoPath);
    assertEquals(fileStatus1.getModificationTime(), fileStatus2.getModificationTime());

    // Start syncUpTool for the third time with force mode,
    // startup will success and create a new replication info file
    syncUp(UTIL1, new String[] { "-f" });
    FileStatus fileStatus3 = fs.getFileStatus(replicationInfoPath);
    assertTrue(fileStatus3.getModificationTime() > fileStatus2.getModificationTime());
  }
}