/*
    * Copyright 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.
   */
  package org.apache.hadoop.hbase.regionserver;
  
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.assertNotNull;
  
  import java.util.UUID;
  
  import org.apache.hadoop.conf.Configuration;
  import org.apache.hadoop.fs.FSDataOutputStream;
  import org.apache.hadoop.fs.FileSystem;
  import org.apache.hadoop.fs.Path;
  import org.apache.hadoop.hbase.CoordinatedStateManager;
  import org.apache.hadoop.hbase.CoordinatedStateManagerFactory;
  import org.apache.hadoop.hbase.HBaseTestingUtility;
  import org.apache.hadoop.hbase.HConstants;
  import org.apache.hadoop.hbase.testclassification.MediumTests;
  import org.apache.hadoop.hbase.master.HMaster;
  import org.apache.hadoop.hbase.util.FSUtils;
  import org.apache.hadoop.hbase.util.JVMClusterUtil;
  import org.apache.hadoop.hbase.zookeeper.ZKClusterId;
  import org.junit.After;
  import org.junit.Before;
  import org.junit.Test;
  import org.junit.experimental.categories.Category;
  
  
  /**
   * Test metrics incremented on region server operations.
   */
  @Category(MediumTests.class)
  public class TestClusterId {
  
    private final HBaseTestingUtility TEST_UTIL =
        new HBaseTestingUtility();
  
    private JVMClusterUtil.RegionServerThread rst;
  
    @Before
    public void setUp() throws Exception {
      TEST_UTIL.getConfiguration().setBoolean(ShutdownHook.RUN_SHUTDOWN_HOOK, false);
    }
  
    @After
    public void tearDown() throws Exception {
      TEST_UTIL.shutdownMiniCluster();
      if(rst != null && rst.getRegionServer() != null) {
        rst.getRegionServer().stop("end of test");
        rst.join();
      }
    }
  
    @Test
    public void testClusterId() throws Exception  {
      TEST_UTIL.startMiniZKCluster();
      TEST_UTIL.startMiniDFSCluster(1);
  
      Configuration conf = new Configuration(TEST_UTIL.getConfiguration());
      CoordinatedStateManager cp = CoordinatedStateManagerFactory.getCoordinatedStateManager(conf);
      //start region server, needs to be separate
      //so we get an unset clusterId
      rst = JVMClusterUtil.createRegionServerThread(conf,cp,
          HRegionServer.class, 0);
      rst.start();
      //Make sure RS is in blocking state
      Thread.sleep(10000);
  
      TEST_UTIL.startMiniHBaseCluster(1, 1);
  
      rst.waitForServerOnline();
  
      String clusterId = ZKClusterId.readClusterIdZNode(TEST_UTIL.getZooKeeperWatcher());
      assertNotNull(clusterId);
      assertEquals(clusterId, rst.getRegionServer().getClusterId());
    }
    
    @Test
    public void testRewritingClusterIdToPB() throws Exception {
      TEST_UTIL.startMiniZKCluster();
      TEST_UTIL.startMiniDFSCluster(1);
      TEST_UTIL.createRootDir();
      TEST_UTIL.getConfiguration().setBoolean("hbase.replication", true);
     Path rootDir = FSUtils.getRootDir(TEST_UTIL.getConfiguration());
     FileSystem fs = rootDir.getFileSystem(TEST_UTIL.getConfiguration());
     Path filePath = new Path(rootDir, HConstants.CLUSTER_ID_FILE_NAME);
     FSDataOutputStream s = null;
     try {
       s = fs.create(filePath);
       s.writeUTF(UUID.randomUUID().toString());
     } finally {
       if (s != null) {
         s.close();
       }
     }
     TEST_UTIL.startMiniHBaseCluster(1, 1);
     HMaster master = TEST_UTIL.getHBaseCluster().getMaster();
     assertEquals(1, master.getServerManager().getOnlineServersList().size());
   }
   
 }