/*
    * 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 static org.junit.Assert.fail;
  
  import org.apache.hadoop.hbase.HBaseTestingUtility;
  import org.apache.hadoop.hbase.HConstants;
  import org.apache.hadoop.hbase.ServerName;
  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;
  
  import java.net.UnknownHostException;
  
  /**
   * Tests that we fail fast when hostname resolution is not working and do not cache
   * unresolved InetSocketAddresses.
   */
  @Category({MediumTests.class, ClientTests.class})
  public class TestConnectionImplementation {
    private static HBaseTestingUtility testUtil;
    private static ConnectionManager.HConnectionImplementation conn;
  
    @BeforeClass
    public static void setupBeforeClass() throws Exception {
      testUtil = HBaseTestingUtility.createLocalHTU();
      testUtil.startMiniCluster();
      conn = (ConnectionManager.HConnectionImplementation) testUtil.getConnection();
    }
  
    @AfterClass
    public static void teardownAfterClass() throws Exception {
      conn.close();
      testUtil.shutdownMiniCluster();
    }
  
    @Test(expected = UnknownHostException.class)
    public void testGetAdminBadHostname() throws Exception {
      // verify that we can get an instance with the cluster hostname
      ServerName master = testUtil.getHBaseCluster().getMaster().getServerName();
      try {
        conn.getAdmin(master);
      } catch (UnknownHostException uhe) {
        fail("Obtaining admin to the cluster master should have succeeded");
      }
  
      // test that we fail to get a client to an unresolvable hostname, which
      // means it won't be cached
      ServerName badHost =
          ServerName.valueOf("unknownhost.example.com:" + HConstants.DEFAULT_MASTER_PORT,
          System.currentTimeMillis());
      conn.getAdmin(badHost);
      fail("Obtaining admin to unresolvable hostname should have failed");
    }
  
    @Test(expected = UnknownHostException.class)
    public void testGetClientBadHostname() throws Exception {
      // verify that we can get an instance with the cluster hostname
      ServerName rs = testUtil.getHBaseCluster().getRegionServer(0).getServerName();
      try {
        conn.getClient(rs);
      } catch (UnknownHostException uhe) {
        fail("Obtaining client to the cluster regionserver should have succeeded");
      }
  
      // test that we fail to get a client to an unresolvable hostname, which
      // means it won't be cached
      ServerName badHost =
          ServerName.valueOf("unknownhost.example.com:" + HConstants.DEFAULT_REGIONSERVER_PORT,
          System.currentTimeMillis());
      conn.getAdmin(badHost);
      fail("Obtaining client to unresolvable hostname should have failed");
    }
  }