001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.hbase.client;
019
020import java.io.IOException;
021import java.util.ArrayList;
022import java.util.List;
023import java.util.concurrent.CompletableFuture;
024import java.util.concurrent.TimeUnit;
025import java.util.concurrent.atomic.AtomicInteger;
026import org.apache.hadoop.conf.Configuration;
027import org.apache.hadoop.hbase.HBaseClassTestRule;
028import org.apache.hadoop.hbase.HBaseConfiguration;
029import org.apache.hadoop.hbase.ServerName;
030import org.apache.hadoop.hbase.Waiter;
031import org.apache.hadoop.hbase.testclassification.ClientTests;
032import org.apache.hadoop.hbase.testclassification.SmallTests;
033import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
034import org.junit.Assert;
035import org.junit.ClassRule;
036import org.junit.Test;
037import org.junit.experimental.categories.Category;
038import org.apache.hbase.thirdparty.com.google.common.util.concurrent.Uninterruptibles;
039
040@Category({ClientTests.class, SmallTests.class})
041public class TestMasterAddressRefresher {
042
043  @ClassRule
044  public static final HBaseClassTestRule CLASS_RULE =
045      HBaseClassTestRule.forClass(TestMasterAddressRefresher.class);
046
047  private class DummyMasterRegistry extends MasterRegistry {
048
049    private final AtomicInteger getMastersCallCounter = new AtomicInteger(0);
050    private final List<Long> callTimeStamps = new ArrayList<>();
051
052    DummyMasterRegistry(Configuration conf) throws IOException {
053      super(conf);
054    }
055
056    @Override
057    CompletableFuture<List<ServerName>> getMasters() {
058      getMastersCallCounter.incrementAndGet();
059      callTimeStamps.add(EnvironmentEdgeManager.currentTime());
060      return CompletableFuture.completedFuture(new ArrayList<>());
061    }
062
063    public int getMastersCount() {
064      return getMastersCallCounter.get();
065    }
066
067    public List<Long> getCallTimeStamps() {
068      return callTimeStamps;
069    }
070  }
071
072  @Test
073  public void testPeriodicMasterEndPointRefresh() throws IOException {
074    Configuration conf = HBaseConfiguration.create();
075    // Refresh every 1 second.
076    conf.setLong(MasterAddressRefresher.PERIODIC_REFRESH_INTERVAL_SECS, 1);
077    conf.setLong(MasterAddressRefresher.MIN_SECS_BETWEEN_REFRESHES, 0);
078    try (DummyMasterRegistry registry = new DummyMasterRegistry(conf)) {
079      // Wait for > 3 seconds to see that at least 3 getMasters() RPCs have been made.
080      Waiter.waitFor(
081          conf, 5000, (Waiter.Predicate<Exception>) () -> registry.getMastersCount() > 3);
082    }
083  }
084
085  @Test
086  public void testDurationBetweenRefreshes() throws IOException {
087    Configuration conf = HBaseConfiguration.create();
088    // Disable periodic refresh
089    conf.setLong(MasterAddressRefresher.PERIODIC_REFRESH_INTERVAL_SECS, Integer.MAX_VALUE);
090    // A minimum duration of 1s between refreshes
091    conf.setLong(MasterAddressRefresher.MIN_SECS_BETWEEN_REFRESHES, 1);
092    try (DummyMasterRegistry registry = new DummyMasterRegistry(conf)) {
093      // Issue a ton of manual refreshes.
094      for (int i = 0; i < 10000; i++) {
095        registry.masterAddressRefresher.refreshNow();
096        Uninterruptibles.sleepUninterruptibly(1, TimeUnit.MILLISECONDS);
097      }
098      // Overall wait time is 10000 ms, so the number of requests should be <=10
099      List<Long> callTimeStamps = registry.getCallTimeStamps();
100      // Actual calls to getMasters() should be much lower than the refresh count.
101      Assert.assertTrue(
102          String.valueOf(registry.getMastersCount()), registry.getMastersCount() <= 20);
103      Assert.assertTrue(callTimeStamps.size() > 0);
104      // Verify that the delta between subsequent RPCs is at least 1sec as configured.
105      for (int i = 1; i < callTimeStamps.size() - 1; i++) {
106        long delta = callTimeStamps.get(i) - callTimeStamps.get(i - 1);
107        // Few ms cushion to account for any env jitter.
108        Assert.assertTrue(callTimeStamps.toString(), delta > 990);
109      }
110    }
111
112  }
113}