/**
    *
    * 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.tool;
  
  import org.apache.hadoop.conf.Configuration;
  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.ServerName;
  import org.apache.hadoop.hbase.TableName;
  import org.apache.hadoop.hbase.client.HTable;
  import org.apache.hadoop.hbase.client.Put;
  import org.apache.hadoop.hbase.master.HMaster;
  import org.apache.hadoop.hbase.testclassification.MediumTests;
  import org.apache.hadoop.hbase.util.Bytes;
  import org.apache.hadoop.hbase.zookeeper.ZKUtil;
  import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
  import org.apache.hadoop.util.ToolRunner;
  import org.apache.log4j.Appender;
  import org.apache.log4j.LogManager;
  import org.apache.log4j.spi.LoggingEvent;
  import org.junit.After;
  import org.junit.Before;
  import org.junit.Test;
  import org.junit.experimental.categories.Category;
  import org.junit.runner.RunWith;
  import org.mockito.ArgumentMatcher;
  import org.mockito.Mock;
  import org.mockito.runners.MockitoJUnitRunner;
  
  
  import java.util.List;
  import java.util.concurrent.ExecutorService;
  import java.util.concurrent.ScheduledThreadPoolExecutor;
  
  import static org.junit.Assert.*;
  import static org.mockito.Matchers.anyLong;
  import static org.mockito.Matchers.isA;
  import static org.mockito.Mockito.atLeastOnce;
  import static org.mockito.Mockito.spy;
  import static org.mockito.Mockito.verify;
  import static org.mockito.Matchers.argThat;
  import static org.mockito.Mockito.never;
  
  @RunWith(MockitoJUnitRunner.class)
  @Category({MediumTests.class})
  public class TestCanaryTool {
  
    private HBaseTestingUtility testingUtility;
    private static final byte[] FAMILY = Bytes.toBytes("f");
    private static final byte[] COLUMN = Bytes.toBytes("col");
  
    @Before
    public void setUp() throws Exception {
      testingUtility = new HBaseTestingUtility();
      testingUtility.startMiniCluster();
      LogManager.getRootLogger().addAppender(mockAppender);
    }
  
    @After
    public void tearDown() throws Exception {
      testingUtility.shutdownMiniCluster();
      LogManager.getRootLogger().removeAppender(mockAppender);
    }
  
    @Mock
    Appender mockAppender;
  
    @Test
    public void testBasicCanaryWorks() throws Exception {
      TableName tableName = TableName.valueOf("testTable");
      HTable table = testingUtility.createTable(tableName, new byte[][] { FAMILY });
      // insert some test rows
      for (int i=0; i<1000; i++) {
        byte[] iBytes = Bytes.toBytes(i);
        Put p = new Put(iBytes);
        p.addColumn(FAMILY, COLUMN, iBytes);
        table.put(p);
      }
      ExecutorService executor = new ScheduledThreadPoolExecutor(1);
      Canary.RegionServerStdOutSink sink = spy(new Canary.RegionServerStdOutSink());
     Canary canary = new Canary(executor, sink);
     String[] args = { "-t", "10000", "testTable" };
     ToolRunner.run(testingUtility.getConfiguration(), canary, args);
     verify(sink, atLeastOnce())
         .publishReadTiming(isA(HRegionInfo.class), isA(HColumnDescriptor.class), anyLong());
   }
 
   //no table created, so there should be no regions
   @Test
   public void testRegionserverNoRegions() throws Exception {
     runRegionserverCanary();
     verify(mockAppender).doAppend(argThat(new ArgumentMatcher<LoggingEvent>() {
       @Override
       public boolean matches(Object argument) {
         return ((LoggingEvent) argument).getRenderedMessage().contains("Regionserver not serving any regions");
       }
     }));
   }
 
   //by creating a table, there shouldn't be any region servers not serving any regions
   @Test
   public void testRegionserverWithRegions() throws Exception {
     TableName tableName = TableName.valueOf("testTable");
     testingUtility.createTable(tableName, new byte[][] { FAMILY });
     runRegionserverCanary();
     verify(mockAppender, never()).doAppend(argThat(new ArgumentMatcher<LoggingEvent>() {
       @Override
       public boolean matches(Object argument) {
         return ((LoggingEvent) argument).getRenderedMessage().contains("Regionserver not serving any regions");
       }
     }));
   }
 
   private void runRegionserverCanary() throws Exception {
     ExecutorService executor = new ScheduledThreadPoolExecutor(1);
     Canary canary = new Canary(executor, new Canary.RegionServerStdOutSink());
     String[] args = { "-t", "10000", "-regionserver"};
     ToolRunner.run(testingUtility.getConfiguration(), canary, args);
   }
 
 }