Madan Jampani | 619453b | 2015-07-22 23:47:09 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2015 Open Networking Laboratory |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
Madan Jampani | f4c8850 | 2016-01-21 12:35:36 -0800 | [diff] [blame] | 16 | package org.onosproject.store.primitives.impl; |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 17 | |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 18 | import com.google.common.collect.ImmutableList; |
Jonathan Hart | e649c75 | 2015-03-03 18:04:25 -0800 | [diff] [blame] | 19 | import com.google.common.collect.ImmutableMap; |
Madan Jampani | 3650fc4 | 2015-05-27 17:01:50 -0700 | [diff] [blame] | 20 | import com.google.common.collect.Iterables; |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 21 | import com.google.common.collect.Lists; |
Madan Jampani | 6f38daf | 2015-06-04 15:26:38 -0700 | [diff] [blame] | 22 | import com.google.common.collect.MapDifference; |
Jonathan Hart | e649c75 | 2015-03-03 18:04:25 -0800 | [diff] [blame] | 23 | import com.google.common.collect.Maps; |
| 24 | import com.google.common.collect.Sets; |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 25 | |
Madan Jampani | 8d37efc | 2015-06-01 17:25:48 -0700 | [diff] [blame] | 26 | import org.apache.commons.lang.math.RandomUtils; |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 27 | import org.apache.felix.scr.annotations.Activate; |
| 28 | import org.apache.felix.scr.annotations.Component; |
| 29 | import org.apache.felix.scr.annotations.Deactivate; |
| 30 | import org.apache.felix.scr.annotations.Reference; |
| 31 | import org.apache.felix.scr.annotations.ReferenceCardinality; |
| 32 | import org.apache.felix.scr.annotations.Service; |
Madan Jampani | cc58675 | 2015-05-18 16:19:27 -0700 | [diff] [blame] | 33 | import org.onosproject.cluster.ClusterEvent; |
| 34 | import org.onosproject.cluster.ClusterEvent.Type; |
| 35 | import org.onosproject.cluster.ClusterEventListener; |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 36 | import org.onosproject.cluster.ClusterService; |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 37 | import org.onosproject.cluster.Leadership; |
| 38 | import org.onosproject.cluster.LeadershipEvent; |
| 39 | import org.onosproject.cluster.LeadershipEventListener; |
| 40 | import org.onosproject.cluster.LeadershipService; |
| 41 | import org.onosproject.cluster.NodeId; |
Simon Hunt | ff66374 | 2015-05-14 13:33:05 -0700 | [diff] [blame] | 42 | import org.onosproject.event.ListenerRegistry; |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 43 | import org.onosproject.event.EventDeliveryService; |
| 44 | import org.onosproject.store.cluster.messaging.ClusterCommunicationService; |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 45 | import org.onosproject.store.serializers.KryoNamespaces; |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 46 | import org.onosproject.store.service.ConsistentMap; |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 47 | import org.onosproject.store.service.ConsistentMapException; |
Madan Jampani | d09441b | 2015-06-09 14:50:55 -0700 | [diff] [blame] | 48 | import org.onosproject.store.service.MapEvent; |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 49 | import org.onosproject.store.service.Serializer; |
| 50 | import org.onosproject.store.service.StorageService; |
| 51 | import org.onosproject.store.service.Versioned; |
| 52 | import org.slf4j.Logger; |
| 53 | |
Madan Jampani | 1af8e13 | 2015-04-30 16:41:18 -0700 | [diff] [blame] | 54 | import java.util.ArrayList; |
Madan Jampani | cc58675 | 2015-05-18 16:19:27 -0700 | [diff] [blame] | 55 | import java.util.Collections; |
Jonathan Hart | e649c75 | 2015-03-03 18:04:25 -0800 | [diff] [blame] | 56 | import java.util.Map; |
| 57 | import java.util.Map.Entry; |
| 58 | import java.util.Objects; |
| 59 | import java.util.Set; |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 60 | import java.util.List; |
Madan Jampani | de003d9 | 2015-05-11 17:14:20 -0700 | [diff] [blame] | 61 | import java.util.concurrent.CancellationException; |
| 62 | import java.util.concurrent.CompletableFuture; |
Jonathan Hart | e649c75 | 2015-03-03 18:04:25 -0800 | [diff] [blame] | 63 | import java.util.concurrent.Executors; |
| 64 | import java.util.concurrent.ScheduledExecutorService; |
| 65 | import java.util.concurrent.TimeUnit; |
Madan Jampani | d46e18f | 2015-05-04 23:19:33 -0700 | [diff] [blame] | 66 | import java.util.concurrent.atomic.AtomicBoolean; |
Jonathan Hart | e649c75 | 2015-03-03 18:04:25 -0800 | [diff] [blame] | 67 | import java.util.stream.Collectors; |
| 68 | |
| 69 | import static com.google.common.base.Preconditions.checkArgument; |
| 70 | import static org.onlab.util.Tools.groupedThreads; |
| 71 | import static org.slf4j.LoggerFactory.getLogger; |
Ayaka Koshibe | 4a3c239 | 2015-04-22 18:03:13 -0700 | [diff] [blame] | 72 | import static org.onosproject.cluster.ControllerNode.State.ACTIVE; |
| 73 | import static org.onosproject.cluster.ControllerNode.State.INACTIVE; |
| 74 | |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 75 | /** |
| 76 | * Distributed Lock Manager implemented on top of ConsistentMap. |
| 77 | * <p> |
Madan Jampani | cc58675 | 2015-05-18 16:19:27 -0700 | [diff] [blame] | 78 | * This implementation makes use of ClusterService's failure |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 79 | * detection capabilities to detect and purge stale locks. |
| 80 | * TODO: Ensure lock safety and liveness. |
| 81 | */ |
Madan Jampani | 7f72c3f | 2015-03-01 17:34:59 -0800 | [diff] [blame] | 82 | @Component(immediate = true, enabled = true) |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 83 | @Service |
| 84 | public class DistributedLeadershipManager implements LeadershipService { |
| 85 | |
| 86 | @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY) |
| 87 | protected StorageService storageService; |
| 88 | |
| 89 | @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY) |
| 90 | protected ClusterService clusterService; |
| 91 | |
| 92 | @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY) |
| 93 | protected ClusterCommunicationService clusterCommunicator; |
| 94 | |
| 95 | @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY) |
| 96 | protected EventDeliveryService eventDispatcher; |
| 97 | |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 98 | private final Logger log = getLogger(getClass()); |
HIGUCHI Yuta | 1979f55 | 2015-12-28 21:24:26 -0800 | [diff] [blame] | 99 | |
Madan Jampani | 7d243db | 2015-05-27 13:16:02 -0700 | [diff] [blame] | 100 | private ScheduledExecutorService electionRunner; |
| 101 | private ScheduledExecutorService lockExecutor; |
Madan Jampani | cc58675 | 2015-05-18 16:19:27 -0700 | [diff] [blame] | 102 | private ScheduledExecutorService staleLeadershipPurgeExecutor; |
Madan Jampani | 6f38daf | 2015-06-04 15:26:38 -0700 | [diff] [blame] | 103 | private ScheduledExecutorService leadershipRefresher; |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 104 | |
HIGUCHI Yuta | 1979f55 | 2015-12-28 21:24:26 -0800 | [diff] [blame] | 105 | // leader for each topic |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 106 | private ConsistentMap<String, NodeId> leaderMap; |
HIGUCHI Yuta | 1979f55 | 2015-12-28 21:24:26 -0800 | [diff] [blame] | 107 | // list of candidates (includes chosen leader) for each topic |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 108 | private ConsistentMap<String, List<NodeId>> candidateMap; |
| 109 | |
Madan Jampani | cc58675 | 2015-05-18 16:19:27 -0700 | [diff] [blame] | 110 | private ListenerRegistry<LeadershipEvent, LeadershipEventListener> listenerRegistry; |
HIGUCHI Yuta | 1979f55 | 2015-12-28 21:24:26 -0800 | [diff] [blame] | 111 | |
| 112 | // cached copy of leaderMap |
| 113 | // Note: Map value, Leadership, does not contain proper candidates info |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 114 | private final Map<String, Leadership> leaderBoard = Maps.newConcurrentMap(); |
HIGUCHI Yuta | 1979f55 | 2015-12-28 21:24:26 -0800 | [diff] [blame] | 115 | // cached copy of candidateMap |
| 116 | // Note: Map value, Leadership, does not contain proper leader info |
Ayaka Koshibe | fd26a30 | 2015-04-13 13:59:54 -0700 | [diff] [blame] | 117 | private final Map<String, Leadership> candidateBoard = Maps.newConcurrentMap(); |
HIGUCHI Yuta | 1979f55 | 2015-12-28 21:24:26 -0800 | [diff] [blame] | 118 | |
Madan Jampani | cc58675 | 2015-05-18 16:19:27 -0700 | [diff] [blame] | 119 | private final ClusterEventListener clusterEventListener = new InternalClusterEventListener(); |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 120 | |
Madan Jampani | cc58675 | 2015-05-18 16:19:27 -0700 | [diff] [blame] | 121 | private NodeId localNodeId; |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 122 | private Set<String> activeTopics = Sets.newConcurrentHashSet(); |
Madan Jampani | 7d243db | 2015-05-27 13:16:02 -0700 | [diff] [blame] | 123 | private Map<String, CompletableFuture<Leadership>> pendingFutures = Maps.newConcurrentMap(); |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 124 | |
Madan Jampani | d09441b | 2015-06-09 14:50:55 -0700 | [diff] [blame] | 125 | // The actual delay is randomly chosen from the interval [0, WAIT_BEFORE_RETRY_MILLIS) |
Madan Jampani | 8d37efc | 2015-06-01 17:25:48 -0700 | [diff] [blame] | 126 | private static final int WAIT_BEFORE_RETRY_MILLIS = 150; |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 127 | private static final int DELAY_BETWEEN_LEADER_LOCK_ATTEMPTS_SEC = 2; |
Madan Jampani | 6f38daf | 2015-06-04 15:26:38 -0700 | [diff] [blame] | 128 | private static final int LEADERSHIP_REFRESH_INTERVAL_SEC = 2; |
Madan Jampani | cc58675 | 2015-05-18 16:19:27 -0700 | [diff] [blame] | 129 | private static final int DELAY_BETWEEN_STALE_LEADERSHIP_PURGE_ATTEMPTS_SEC = 2; |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 130 | |
Madan Jampani | cc58675 | 2015-05-18 16:19:27 -0700 | [diff] [blame] | 131 | private final AtomicBoolean staleLeadershipPurgeScheduled = new AtomicBoolean(false); |
| 132 | |
Madan Jampani | d09441b | 2015-06-09 14:50:55 -0700 | [diff] [blame] | 133 | private static final Serializer SERIALIZER = Serializer.using(KryoNamespaces.API); |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 134 | |
| 135 | @Activate |
| 136 | public void activate() { |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 137 | leaderMap = storageService.<String, NodeId>consistentMapBuilder() |
| 138 | .withName("onos-topic-leaders") |
| 139 | .withSerializer(SERIALIZER) |
| 140 | .withPartitionsDisabled().build(); |
| 141 | candidateMap = storageService.<String, List<NodeId>>consistentMapBuilder() |
| 142 | .withName("onos-topic-candidates") |
| 143 | .withSerializer(SERIALIZER) |
| 144 | .withPartitionsDisabled().build(); |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 145 | |
Madan Jampani | d09441b | 2015-06-09 14:50:55 -0700 | [diff] [blame] | 146 | leaderMap.addListener(event -> { |
| 147 | log.debug("Received {}", event); |
| 148 | LeadershipEvent.Type leadershipEventType = null; |
| 149 | if (event.type() == MapEvent.Type.INSERT || event.type() == MapEvent.Type.UPDATE) { |
| 150 | leadershipEventType = LeadershipEvent.Type.LEADER_ELECTED; |
| 151 | } else if (event.type() == MapEvent.Type.REMOVE) { |
| 152 | leadershipEventType = LeadershipEvent.Type.LEADER_BOOTED; |
| 153 | } |
| 154 | onLeadershipEvent(new LeadershipEvent( |
| 155 | leadershipEventType, |
| 156 | new Leadership(event.key(), |
| 157 | event.value().value(), |
| 158 | event.value().version(), |
| 159 | event.value().creationTime()))); |
| 160 | }); |
| 161 | |
| 162 | candidateMap.addListener(event -> { |
| 163 | log.debug("Received {}", event); |
| 164 | if (event.type() != MapEvent.Type.INSERT && event.type() != MapEvent.Type.UPDATE) { |
| 165 | log.error("Entries must not be removed from candidate map"); |
| 166 | return; |
| 167 | } |
| 168 | onLeadershipEvent(new LeadershipEvent( |
| 169 | LeadershipEvent.Type.CANDIDATES_CHANGED, |
| 170 | new Leadership(event.key(), |
| 171 | event.value().value(), |
| 172 | event.value().version(), |
| 173 | event.value().creationTime()))); |
| 174 | }); |
| 175 | |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 176 | localNodeId = clusterService.getLocalNode().id(); |
| 177 | |
Madan Jampani | 7d243db | 2015-05-27 13:16:02 -0700 | [diff] [blame] | 178 | electionRunner = Executors.newSingleThreadScheduledExecutor( |
| 179 | groupedThreads("onos/store/leadership", "election-runner")); |
| 180 | lockExecutor = Executors.newScheduledThreadPool( |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 181 | 4, groupedThreads("onos/store/leadership", "election-thread-%d")); |
Madan Jampani | cc58675 | 2015-05-18 16:19:27 -0700 | [diff] [blame] | 182 | staleLeadershipPurgeExecutor = Executors.newSingleThreadScheduledExecutor( |
| 183 | groupedThreads("onos/store/leadership", "stale-leadership-evictor")); |
Madan Jampani | 6f38daf | 2015-06-04 15:26:38 -0700 | [diff] [blame] | 184 | leadershipRefresher = Executors.newSingleThreadScheduledExecutor( |
| 185 | groupedThreads("onos/store/leadership", "refresh-thread")); |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 186 | |
Madan Jampani | cc58675 | 2015-05-18 16:19:27 -0700 | [diff] [blame] | 187 | clusterService.addListener(clusterEventListener); |
| 188 | |
Madan Jampani | 7d243db | 2015-05-27 13:16:02 -0700 | [diff] [blame] | 189 | electionRunner.scheduleWithFixedDelay( |
| 190 | this::electLeaders, 0, DELAY_BETWEEN_LEADER_LOCK_ATTEMPTS_SEC, TimeUnit.SECONDS); |
| 191 | |
Madan Jampani | 6f38daf | 2015-06-04 15:26:38 -0700 | [diff] [blame] | 192 | leadershipRefresher.scheduleWithFixedDelay( |
| 193 | this::refreshLeaderBoard, 0, LEADERSHIP_REFRESH_INTERVAL_SEC, TimeUnit.SECONDS); |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 194 | |
Simon Hunt | ff66374 | 2015-05-14 13:33:05 -0700 | [diff] [blame] | 195 | listenerRegistry = new ListenerRegistry<>(); |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 196 | eventDispatcher.addSink(LeadershipEvent.class, listenerRegistry); |
| 197 | |
Madan Jampani | d46e18f | 2015-05-04 23:19:33 -0700 | [diff] [blame] | 198 | log.info("Started"); |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 199 | } |
| 200 | |
| 201 | @Deactivate |
| 202 | public void deactivate() { |
Thomas Vachuska | c0e2013 | 2015-07-31 12:15:42 -0700 | [diff] [blame] | 203 | if (clusterService.getNodes().size() > 1) { |
| 204 | // FIXME: Determine why this takes ~50 seconds to shutdown on a single node! |
| 205 | leaderBoard.forEach((topic, leadership) -> { |
| 206 | if (localNodeId.equals(leadership.leader())) { |
| 207 | withdraw(topic); |
| 208 | } |
| 209 | }); |
| 210 | } |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 211 | |
Madan Jampani | cc58675 | 2015-05-18 16:19:27 -0700 | [diff] [blame] | 212 | clusterService.removeListener(clusterEventListener); |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 213 | eventDispatcher.removeSink(LeadershipEvent.class); |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 214 | |
Madan Jampani | 7d243db | 2015-05-27 13:16:02 -0700 | [diff] [blame] | 215 | electionRunner.shutdown(); |
Madan Jampani | 7d243db | 2015-05-27 13:16:02 -0700 | [diff] [blame] | 216 | lockExecutor.shutdown(); |
Madan Jampani | cc58675 | 2015-05-18 16:19:27 -0700 | [diff] [blame] | 217 | staleLeadershipPurgeExecutor.shutdown(); |
Madan Jampani | 6f38daf | 2015-06-04 15:26:38 -0700 | [diff] [blame] | 218 | leadershipRefresher.shutdown(); |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 219 | |
Madan Jampani | d46e18f | 2015-05-04 23:19:33 -0700 | [diff] [blame] | 220 | log.info("Stopped"); |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 221 | } |
| 222 | |
| 223 | @Override |
| 224 | public Map<String, Leadership> getLeaderBoard() { |
| 225 | return ImmutableMap.copyOf(leaderBoard); |
| 226 | } |
| 227 | |
| 228 | @Override |
Madan Jampani | fd45d5e | 2015-04-20 13:33:21 -0700 | [diff] [blame] | 229 | public Map<String, List<NodeId>> getCandidates() { |
| 230 | return Maps.toMap(candidateBoard.keySet(), this::getCandidates); |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 231 | } |
| 232 | |
| 233 | @Override |
| 234 | public List<NodeId> getCandidates(String path) { |
Ayaka Koshibe | fd26a30 | 2015-04-13 13:59:54 -0700 | [diff] [blame] | 235 | Leadership current = candidateBoard.get(path); |
| 236 | return current == null ? ImmutableList.of() : ImmutableList.copyOf(current.candidates()); |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 237 | } |
| 238 | |
| 239 | @Override |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 240 | public NodeId getLeader(String path) { |
| 241 | Leadership leadership = leaderBoard.get(path); |
| 242 | return leadership != null ? leadership.leader() : null; |
| 243 | } |
| 244 | |
| 245 | @Override |
Madan Jampani | 5961051 | 2015-02-25 15:25:43 -0800 | [diff] [blame] | 246 | public Leadership getLeadership(String path) { |
| 247 | checkArgument(path != null); |
| 248 | return leaderBoard.get(path); |
| 249 | } |
| 250 | |
| 251 | @Override |
| 252 | public Set<String> ownedTopics(NodeId nodeId) { |
| 253 | checkArgument(nodeId != null); |
| 254 | return leaderBoard.entrySet() |
| 255 | .stream() |
| 256 | .filter(entry -> nodeId.equals(entry.getValue().leader())) |
| 257 | .map(Entry::getKey) |
| 258 | .collect(Collectors.toSet()); |
| 259 | } |
| 260 | |
| 261 | @Override |
Madan Jampani | de003d9 | 2015-05-11 17:14:20 -0700 | [diff] [blame] | 262 | public CompletableFuture<Leadership> runForLeadership(String path) { |
Madan Jampani | 52860be | 2015-02-27 12:52:37 -0800 | [diff] [blame] | 263 | log.debug("Running for leadership for topic: {}", path); |
Madan Jampani | de003d9 | 2015-05-11 17:14:20 -0700 | [diff] [blame] | 264 | CompletableFuture<Leadership> resultFuture = new CompletableFuture<>(); |
| 265 | doRunForLeadership(path, resultFuture); |
| 266 | return resultFuture; |
| 267 | } |
| 268 | |
| 269 | private void doRunForLeadership(String path, CompletableFuture<Leadership> future) { |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 270 | try { |
Madan Jampani | 346d4f5 | 2015-05-04 11:09:39 -0700 | [diff] [blame] | 271 | Versioned<List<NodeId>> candidates = candidateMap.computeIf(path, |
| 272 | currentList -> currentList == null || !currentList.contains(localNodeId), |
| 273 | (topic, currentList) -> { |
| 274 | if (currentList == null) { |
| 275 | return ImmutableList.of(localNodeId); |
| 276 | } else { |
| 277 | List<NodeId> newList = Lists.newLinkedList(); |
| 278 | newList.addAll(currentList); |
| 279 | newList.add(localNodeId); |
| 280 | return newList; |
| 281 | } |
| 282 | }); |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 283 | log.debug("In the leadership race for topic {} with candidates {}", path, candidates); |
| 284 | activeTopics.add(path); |
Madan Jampani | 7d243db | 2015-05-27 13:16:02 -0700 | [diff] [blame] | 285 | Leadership leadership = electLeader(path, candidates.value()); |
| 286 | if (leadership == null) { |
| 287 | pendingFutures.put(path, future); |
| 288 | } else { |
| 289 | future.complete(leadership); |
| 290 | } |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 291 | } catch (ConsistentMapException e) { |
| 292 | log.debug("Failed to enter topic leader race for {}. Retrying.", path, e); |
Madan Jampani | de003d9 | 2015-05-11 17:14:20 -0700 | [diff] [blame] | 293 | rerunForLeadership(path, future); |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 294 | } |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 295 | } |
| 296 | |
| 297 | @Override |
Madan Jampani | de003d9 | 2015-05-11 17:14:20 -0700 | [diff] [blame] | 298 | public CompletableFuture<Void> withdraw(String path) { |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 299 | activeTopics.remove(path); |
Madan Jampani | de003d9 | 2015-05-11 17:14:20 -0700 | [diff] [blame] | 300 | CompletableFuture<Void> resultFuture = new CompletableFuture<>(); |
| 301 | doWithdraw(path, resultFuture); |
| 302 | return resultFuture; |
| 303 | } |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 304 | |
Madan Jampani | de003d9 | 2015-05-11 17:14:20 -0700 | [diff] [blame] | 305 | |
| 306 | private void doWithdraw(String path, CompletableFuture<Void> future) { |
| 307 | if (activeTopics.contains(path)) { |
| 308 | future.completeExceptionally(new CancellationException(String.format("%s is now a active topic", path))); |
| 309 | } |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 310 | try { |
Madan Jampani | d09441b | 2015-06-09 14:50:55 -0700 | [diff] [blame] | 311 | leaderMap.computeIf(path, |
| 312 | localNodeId::equals, |
| 313 | (topic, leader) -> null); |
| 314 | candidateMap.computeIf(path, |
| 315 | candidates -> candidates != null && candidates.contains(localNodeId), |
| 316 | (topic, candidates) -> candidates.stream() |
| 317 | .filter(nodeId -> !localNodeId.equals(nodeId)) |
| 318 | .collect(Collectors.toList())); |
Madan Jampani | 052ad65 | 2015-06-10 13:20:32 -0700 | [diff] [blame] | 319 | future.complete(null); |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 320 | } catch (Exception e) { |
Madan Jampani | a14047d | 2015-02-25 12:23:02 -0800 | [diff] [blame] | 321 | log.debug("Failed to verify (and clear) any lock this node might be holding for {}", path, e); |
Madan Jampani | de003d9 | 2015-05-11 17:14:20 -0700 | [diff] [blame] | 322 | retryWithdraw(path, future); |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 323 | } |
| 324 | } |
| 325 | |
| 326 | @Override |
Madan Jampani | 1af8e13 | 2015-04-30 16:41:18 -0700 | [diff] [blame] | 327 | public boolean stepdown(String path) { |
Madan Jampani | 9bd1f15 | 2015-04-30 23:33:35 -0700 | [diff] [blame] | 328 | if (!activeTopics.contains(path) || !Objects.equals(localNodeId, getLeader(path))) { |
Madan Jampani | 1af8e13 | 2015-04-30 16:41:18 -0700 | [diff] [blame] | 329 | return false; |
| 330 | } |
| 331 | |
| 332 | try { |
Madan Jampani | d09441b | 2015-06-09 14:50:55 -0700 | [diff] [blame] | 333 | return leaderMap.computeIf(path, |
| 334 | localNodeId::equals, |
| 335 | (topic, leader) -> null) == null; |
Madan Jampani | 1af8e13 | 2015-04-30 16:41:18 -0700 | [diff] [blame] | 336 | } catch (Exception e) { |
| 337 | log.warn("Error executing stepdown for {}", path, e); |
| 338 | } |
| 339 | return false; |
| 340 | } |
| 341 | |
| 342 | @Override |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 343 | public void addListener(LeadershipEventListener listener) { |
| 344 | listenerRegistry.addListener(listener); |
| 345 | } |
| 346 | |
| 347 | @Override |
| 348 | public void removeListener(LeadershipEventListener listener) { |
| 349 | listenerRegistry.removeListener(listener); |
| 350 | } |
| 351 | |
Madan Jampani | 1af8e13 | 2015-04-30 16:41:18 -0700 | [diff] [blame] | 352 | @Override |
| 353 | public boolean makeTopCandidate(String path, NodeId nodeId) { |
Madan Jampani | d09441b | 2015-06-09 14:50:55 -0700 | [diff] [blame] | 354 | Versioned<List<NodeId>> candidateList = candidateMap.computeIf(path, |
Madan Jampani | 3650fc4 | 2015-05-27 17:01:50 -0700 | [diff] [blame] | 355 | candidates -> candidates != null && |
| 356 | candidates.contains(nodeId) && |
| 357 | !nodeId.equals(Iterables.getFirst(candidates, null)), |
Madan Jampani | 346d4f5 | 2015-05-04 11:09:39 -0700 | [diff] [blame] | 358 | (topic, candidates) -> { |
| 359 | List<NodeId> updatedCandidates = new ArrayList<>(candidates.size()); |
| 360 | updatedCandidates.add(nodeId); |
| 361 | candidates.stream().filter(id -> !nodeId.equals(id)).forEach(updatedCandidates::add); |
| 362 | return updatedCandidates; |
| 363 | }); |
Madan Jampani | d09441b | 2015-06-09 14:50:55 -0700 | [diff] [blame] | 364 | List<NodeId> candidates = candidateList != null ? candidateList.value() : Collections.emptyList(); |
| 365 | return candidates.size() > 0 && nodeId.equals(candidates.get(0)); |
Madan Jampani | 1af8e13 | 2015-04-30 16:41:18 -0700 | [diff] [blame] | 366 | } |
| 367 | |
Madan Jampani | 7d243db | 2015-05-27 13:16:02 -0700 | [diff] [blame] | 368 | private Leadership electLeader(String path, List<NodeId> candidates) { |
| 369 | Leadership currentLeadership = getLeadership(path); |
| 370 | if (currentLeadership != null) { |
| 371 | return currentLeadership; |
| 372 | } else { |
| 373 | NodeId topCandidate = candidates |
| 374 | .stream() |
| 375 | .filter(n -> clusterService.getState(n) == ACTIVE) |
| 376 | .findFirst() |
| 377 | .orElse(null); |
| 378 | try { |
| 379 | Versioned<NodeId> leader = localNodeId.equals(topCandidate) |
| 380 | ? leaderMap.computeIfAbsent(path, p -> localNodeId) : leaderMap.get(path); |
| 381 | if (leader != null) { |
| 382 | Leadership newLeadership = new Leadership(path, |
| 383 | leader.value(), |
| 384 | leader.version(), |
| 385 | leader.creationTime()); |
Madan Jampani | 565a66a | 2015-07-25 17:01:13 -0700 | [diff] [blame] | 386 | // Since reads only go through the local copy of leader board, we ought to update it |
| 387 | // first before returning from this method. |
| 388 | // This is to ensure a subsequent read will not read a stale value. |
| 389 | onLeadershipEvent(new LeadershipEvent(LeadershipEvent.Type.LEADER_ELECTED, newLeadership)); |
Madan Jampani | 7d243db | 2015-05-27 13:16:02 -0700 | [diff] [blame] | 390 | return newLeadership; |
Ayaka Koshibe | 0d886fc | 2015-04-23 11:53:41 -0700 | [diff] [blame] | 391 | } |
Madan Jampani | 7d243db | 2015-05-27 13:16:02 -0700 | [diff] [blame] | 392 | } catch (Exception e) { |
| 393 | log.debug("Failed to elect leader for {}", path, e); |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 394 | } |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 395 | } |
Madan Jampani | 7d243db | 2015-05-27 13:16:02 -0700 | [diff] [blame] | 396 | return null; |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 397 | } |
| 398 | |
Madan Jampani | 7d243db | 2015-05-27 13:16:02 -0700 | [diff] [blame] | 399 | private void electLeaders() { |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 400 | try { |
Madan Jampani | 7d243db | 2015-05-27 13:16:02 -0700 | [diff] [blame] | 401 | candidateMap.entrySet().forEach(entry -> { |
| 402 | String path = entry.getKey(); |
Madan Jampani | cd40e5b | 2015-05-27 17:19:48 -0700 | [diff] [blame] | 403 | Versioned<List<NodeId>> candidates = entry.getValue(); |
| 404 | // for active topics, check if this node can become a leader (if it isn't already) |
Madan Jampani | 7d243db | 2015-05-27 13:16:02 -0700 | [diff] [blame] | 405 | if (activeTopics.contains(path)) { |
| 406 | lockExecutor.submit(() -> { |
Madan Jampani | cd40e5b | 2015-05-27 17:19:48 -0700 | [diff] [blame] | 407 | Leadership leadership = electLeader(path, candidates.value()); |
Madan Jampani | 7d243db | 2015-05-27 13:16:02 -0700 | [diff] [blame] | 408 | if (leadership != null) { |
| 409 | CompletableFuture<Leadership> future = pendingFutures.remove(path); |
| 410 | if (future != null) { |
| 411 | future.complete(leadership); |
| 412 | } |
| 413 | } |
| 414 | }); |
| 415 | } |
Madan Jampani | cd40e5b | 2015-05-27 17:19:48 -0700 | [diff] [blame] | 416 | // Raise a CANDIDATES_CHANGED event to force refresh local candidate board |
| 417 | // and also to update local listeners. |
| 418 | // Don't worry about duplicate events as they will be suppressed. |
| 419 | onLeadershipEvent(new LeadershipEvent(LeadershipEvent.Type.CANDIDATES_CHANGED, |
| 420 | new Leadership(path, |
| 421 | candidates.value(), |
| 422 | candidates.version(), |
| 423 | candidates.creationTime()))); |
Madan Jampani | 7d243db | 2015-05-27 13:16:02 -0700 | [diff] [blame] | 424 | }); |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 425 | } catch (Exception e) { |
Madan Jampani | 7d243db | 2015-05-27 13:16:02 -0700 | [diff] [blame] | 426 | log.debug("Failure electing leaders", e); |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 427 | } |
| 428 | } |
| 429 | |
Madan Jampani | d46e18f | 2015-05-04 23:19:33 -0700 | [diff] [blame] | 430 | private void onLeadershipEvent(LeadershipEvent leadershipEvent) { |
| 431 | log.trace("Leadership Event: time = {} type = {} event = {}", |
| 432 | leadershipEvent.time(), leadershipEvent.type(), |
| 433 | leadershipEvent); |
| 434 | |
| 435 | Leadership leadershipUpdate = leadershipEvent.subject(); |
| 436 | LeadershipEvent.Type eventType = leadershipEvent.type(); |
| 437 | String topic = leadershipUpdate.topic(); |
| 438 | |
| 439 | AtomicBoolean updateAccepted = new AtomicBoolean(false); |
| 440 | if (eventType.equals(LeadershipEvent.Type.LEADER_ELECTED)) { |
| 441 | leaderBoard.compute(topic, (k, currentLeadership) -> { |
| 442 | if (currentLeadership == null || currentLeadership.epoch() < leadershipUpdate.epoch()) { |
| 443 | updateAccepted.set(true); |
| 444 | return leadershipUpdate; |
| 445 | } |
| 446 | return currentLeadership; |
| 447 | }); |
| 448 | } else if (eventType.equals(LeadershipEvent.Type.LEADER_BOOTED)) { |
| 449 | leaderBoard.compute(topic, (k, currentLeadership) -> { |
| 450 | if (currentLeadership == null || currentLeadership.epoch() <= leadershipUpdate.epoch()) { |
| 451 | updateAccepted.set(true); |
Madan Jampani | 6f38daf | 2015-06-04 15:26:38 -0700 | [diff] [blame] | 452 | // FIXME: Removing entries from leaderboard is not safe and should be visited. |
Madan Jampani | d46e18f | 2015-05-04 23:19:33 -0700 | [diff] [blame] | 453 | return null; |
| 454 | } |
| 455 | return currentLeadership; |
| 456 | }); |
| 457 | } else if (eventType.equals(LeadershipEvent.Type.CANDIDATES_CHANGED)) { |
| 458 | candidateBoard.compute(topic, (k, currentInfo) -> { |
| 459 | if (currentInfo == null || currentInfo.epoch() < leadershipUpdate.epoch()) { |
| 460 | updateAccepted.set(true); |
| 461 | return leadershipUpdate; |
| 462 | } |
| 463 | return currentInfo; |
| 464 | }); |
| 465 | } else { |
| 466 | throw new IllegalStateException("Unknown event type."); |
Ayaka Koshibe | fd26a30 | 2015-04-13 13:59:54 -0700 | [diff] [blame] | 467 | } |
Ayaka Koshibe | fd26a30 | 2015-04-13 13:59:54 -0700 | [diff] [blame] | 468 | |
Madan Jampani | d46e18f | 2015-05-04 23:19:33 -0700 | [diff] [blame] | 469 | if (updateAccepted.get()) { |
| 470 | eventDispatcher.post(leadershipEvent); |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 471 | } |
| 472 | } |
| 473 | |
Madan Jampani | de003d9 | 2015-05-11 17:14:20 -0700 | [diff] [blame] | 474 | private void rerunForLeadership(String path, CompletableFuture<Leadership> future) { |
Madan Jampani | 7d243db | 2015-05-27 13:16:02 -0700 | [diff] [blame] | 475 | lockExecutor.schedule( |
Madan Jampani | de003d9 | 2015-05-11 17:14:20 -0700 | [diff] [blame] | 476 | () -> doRunForLeadership(path, future), |
Madan Jampani | 8d37efc | 2015-06-01 17:25:48 -0700 | [diff] [blame] | 477 | RandomUtils.nextInt(WAIT_BEFORE_RETRY_MILLIS), |
| 478 | TimeUnit.MILLISECONDS); |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 479 | } |
| 480 | |
Madan Jampani | de003d9 | 2015-05-11 17:14:20 -0700 | [diff] [blame] | 481 | private void retryWithdraw(String path, CompletableFuture<Void> future) { |
Madan Jampani | 7d243db | 2015-05-27 13:16:02 -0700 | [diff] [blame] | 482 | lockExecutor.schedule( |
Madan Jampani | de003d9 | 2015-05-11 17:14:20 -0700 | [diff] [blame] | 483 | () -> doWithdraw(path, future), |
Madan Jampani | 8d37efc | 2015-06-01 17:25:48 -0700 | [diff] [blame] | 484 | RandomUtils.nextInt(WAIT_BEFORE_RETRY_MILLIS), |
| 485 | TimeUnit.MILLISECONDS); |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 486 | } |
| 487 | |
Madan Jampani | cc58675 | 2015-05-18 16:19:27 -0700 | [diff] [blame] | 488 | private void scheduleStaleLeadershipPurge(int afterDelaySec) { |
| 489 | if (staleLeadershipPurgeScheduled.compareAndSet(false, true)) { |
| 490 | staleLeadershipPurgeExecutor.schedule( |
| 491 | this::purgeStaleLeadership, |
| 492 | afterDelaySec, |
| 493 | TimeUnit.SECONDS); |
| 494 | } |
| 495 | } |
| 496 | |
| 497 | /** |
| 498 | * Purges locks held by inactive nodes and evicts inactive nodes from candidacy. |
| 499 | */ |
| 500 | private void purgeStaleLeadership() { |
| 501 | AtomicBoolean rerunPurge = new AtomicBoolean(false); |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 502 | try { |
Madan Jampani | cc58675 | 2015-05-18 16:19:27 -0700 | [diff] [blame] | 503 | staleLeadershipPurgeScheduled.set(false); |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 504 | leaderMap.entrySet() |
| 505 | .stream() |
Ayaka Koshibe | 4a3c239 | 2015-04-22 18:03:13 -0700 | [diff] [blame] | 506 | .filter(e -> clusterService.getState(e.getValue().value()) == INACTIVE) |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 507 | .forEach(entry -> { |
| 508 | String path = entry.getKey(); |
| 509 | NodeId nodeId = entry.getValue().value(); |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 510 | try { |
Madan Jampani | d09441b | 2015-06-09 14:50:55 -0700 | [diff] [blame] | 511 | leaderMap.computeIf(path, nodeId::equals, (topic, leader) -> null); |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 512 | } catch (Exception e) { |
Madan Jampani | ce8392b | 2015-05-20 11:13:47 -0700 | [diff] [blame] | 513 | log.debug("Failed to purge stale lock held by {} for {}", nodeId, path, e); |
Madan Jampani | cc58675 | 2015-05-18 16:19:27 -0700 | [diff] [blame] | 514 | rerunPurge.set(true); |
| 515 | } |
| 516 | }); |
| 517 | |
| 518 | candidateMap.entrySet() |
| 519 | .forEach(entry -> { |
| 520 | String path = entry.getKey(); |
| 521 | Versioned<List<NodeId>> candidates = entry.getValue(); |
| 522 | List<NodeId> candidatesList = candidates != null |
| 523 | ? candidates.value() : Collections.emptyList(); |
| 524 | List<NodeId> activeCandidatesList = |
| 525 | candidatesList.stream() |
| 526 | .filter(n -> clusterService.getState(n) == ACTIVE) |
| 527 | .filter(n -> !localNodeId.equals(n) || activeTopics.contains(path)) |
| 528 | .collect(Collectors.toList()); |
| 529 | if (activeCandidatesList.size() < candidatesList.size()) { |
| 530 | Set<NodeId> removedCandidates = |
| 531 | Sets.difference(Sets.newHashSet(candidatesList), |
| 532 | Sets.newHashSet(activeCandidatesList)); |
| 533 | try { |
Madan Jampani | d09441b | 2015-06-09 14:50:55 -0700 | [diff] [blame] | 534 | candidateMap.computeIf(path, |
| 535 | c -> c.stream() |
| 536 | .filter(n -> clusterService.getState(n) == INACTIVE) |
| 537 | .count() > 0, |
| 538 | (topic, c) -> c.stream() |
| 539 | .filter(n -> clusterService.getState(n) == ACTIVE) |
| 540 | .filter(n -> !localNodeId.equals(n) || |
| 541 | activeTopics.contains(path)) |
| 542 | .collect(Collectors.toList())); |
Madan Jampani | cc58675 | 2015-05-18 16:19:27 -0700 | [diff] [blame] | 543 | } catch (Exception e) { |
Madan Jampani | ce8392b | 2015-05-20 11:13:47 -0700 | [diff] [blame] | 544 | log.debug("Failed to evict inactive candidates {} from " |
Madan Jampani | cc58675 | 2015-05-18 16:19:27 -0700 | [diff] [blame] | 545 | + "candidate list for {}", removedCandidates, path, e); |
| 546 | rerunPurge.set(true); |
| 547 | } |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 548 | } |
Ayaka Koshibe | c19b8b8 | 2015-04-08 15:18:24 -0700 | [diff] [blame] | 549 | }); |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 550 | } catch (Exception e) { |
Madan Jampani | ce8392b | 2015-05-20 11:13:47 -0700 | [diff] [blame] | 551 | log.debug("Failure purging state leadership.", e); |
Madan Jampani | cc58675 | 2015-05-18 16:19:27 -0700 | [diff] [blame] | 552 | rerunPurge.set(true); |
| 553 | } |
| 554 | |
| 555 | if (rerunPurge.get()) { |
Madan Jampani | ce8392b | 2015-05-20 11:13:47 -0700 | [diff] [blame] | 556 | log.debug("Rescheduling stale leadership purge due to errors encountered in previous run"); |
Madan Jampani | cc58675 | 2015-05-18 16:19:27 -0700 | [diff] [blame] | 557 | scheduleStaleLeadershipPurge(DELAY_BETWEEN_STALE_LEADERSHIP_PURGE_ATTEMPTS_SEC); |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 558 | } |
| 559 | } |
| 560 | |
Madan Jampani | 6f38daf | 2015-06-04 15:26:38 -0700 | [diff] [blame] | 561 | private void refreshLeaderBoard() { |
Madan Jampani | a14047d | 2015-02-25 12:23:02 -0800 | [diff] [blame] | 562 | try { |
Madan Jampani | 6f38daf | 2015-06-04 15:26:38 -0700 | [diff] [blame] | 563 | Map<String, Leadership> newLeaderBoard = Maps.newHashMap(); |
| 564 | leaderMap.entrySet().forEach(entry -> { |
| 565 | String path = entry.getKey(); |
| 566 | Versioned<NodeId> leader = entry.getValue(); |
| 567 | Leadership leadership = new Leadership(path, |
| 568 | leader.value(), |
| 569 | leader.version(), |
| 570 | leader.creationTime()); |
| 571 | newLeaderBoard.put(path, leadership); |
| 572 | }); |
| 573 | |
| 574 | // first take snapshot of current leader board. |
| 575 | Map<String, Leadership> currentLeaderBoard = ImmutableMap.copyOf(leaderBoard); |
| 576 | |
| 577 | MapDifference<String, Leadership> diff = Maps.difference(currentLeaderBoard, newLeaderBoard); |
| 578 | |
| 579 | // evict stale leaders |
| 580 | diff.entriesOnlyOnLeft().forEach((path, leadership) -> { |
| 581 | log.debug("Evicting {} from leaderboard. It is no longer active leader.", leadership); |
| 582 | onLeadershipEvent(new LeadershipEvent(LeadershipEvent.Type.LEADER_BOOTED, leadership)); |
| 583 | }); |
| 584 | |
| 585 | // add missing leaders |
| 586 | diff.entriesOnlyOnRight().forEach((path, leadership) -> { |
| 587 | log.debug("Adding {} to leaderboard. It is now the active leader.", leadership); |
| 588 | onLeadershipEvent(new LeadershipEvent(LeadershipEvent.Type.LEADER_ELECTED, leadership)); |
| 589 | }); |
| 590 | |
| 591 | // add updated leaders |
| 592 | diff.entriesDiffering().forEach((path, difference) -> { |
| 593 | Leadership current = difference.leftValue(); |
| 594 | Leadership updated = difference.rightValue(); |
| 595 | if (current.epoch() < updated.epoch()) { |
| 596 | log.debug("Updated {} in leaderboard.", updated); |
| 597 | onLeadershipEvent(new LeadershipEvent(LeadershipEvent.Type.LEADER_ELECTED, updated)); |
Madan Jampani | 096da0e | 2015-06-04 14:30:19 -0700 | [diff] [blame] | 598 | } |
Madan Jampani | a14047d | 2015-02-25 12:23:02 -0800 | [diff] [blame] | 599 | }); |
| 600 | } catch (Exception e) { |
Madan Jampani | 6f38daf | 2015-06-04 15:26:38 -0700 | [diff] [blame] | 601 | log.debug("Failed to refresh leader board", e); |
Madan Jampani | a14047d | 2015-02-25 12:23:02 -0800 | [diff] [blame] | 602 | } |
Madan Jampani | d14166a | 2015-02-24 17:37:51 -0800 | [diff] [blame] | 603 | } |
Madan Jampani | cc58675 | 2015-05-18 16:19:27 -0700 | [diff] [blame] | 604 | |
| 605 | private class InternalClusterEventListener implements ClusterEventListener { |
| 606 | |
| 607 | @Override |
| 608 | public void event(ClusterEvent event) { |
| 609 | if (event.type() == Type.INSTANCE_DEACTIVATED || event.type() == Type.INSTANCE_REMOVED) { |
| 610 | scheduleStaleLeadershipPurge(0); |
| 611 | } |
| 612 | } |
| 613 | } |
Madan Jampani | a14047d | 2015-02-25 12:23:02 -0800 | [diff] [blame] | 614 | } |