opendaylight/md-sal/sal-akka-raft/src/test/java/org/opendaylight/controller/cluster/raft/behaviors/CandidateTest.java

   1 /*
   2  * Copyright (c) 2014, 2015 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8
   9 package org.opendaylight.controller.cluster.raft.behaviors;
  10
  11 import static org.junit.Assert.assertEquals;
  12 import static org.junit.Assert.assertTrue;
  13
  14 import akka.actor.ActorRef;
  15 import akka.dispatch.Dispatchers;
  16 import akka.testkit.TestActorRef;
  17 import com.google.common.base.Stopwatch;
  18 import java.util.ArrayList;
  19 import java.util.Collections;
  20 import java.util.HashMap;
  21 import java.util.List;
  22 import java.util.Map;
  23 import java.util.concurrent.TimeUnit;
  24 import org.junit.After;
  25 import org.junit.Before;
  26 import org.junit.Test;
  27 import org.mockito.Mockito;
  28 import org.opendaylight.controller.cluster.NonPersistentDataProvider;
  29 import org.opendaylight.controller.cluster.raft.DefaultConfigParamsImpl;
  30 import org.opendaylight.controller.cluster.raft.ElectionTerm;
  31 import org.opendaylight.controller.cluster.raft.MockRaftActorContext;
  32 import org.opendaylight.controller.cluster.raft.RaftActorContext;
  33 import org.opendaylight.controller.cluster.raft.RaftActorContextImpl;
  34 import org.opendaylight.controller.cluster.raft.RaftState;
  35 import org.opendaylight.controller.cluster.raft.ReplicatedLogEntry;
  36 import org.opendaylight.controller.cluster.raft.VotingState;
  37 import org.opendaylight.controller.cluster.raft.base.messages.ElectionTimeout;
  38 import org.opendaylight.controller.cluster.raft.messages.AppendEntries;
  39 import org.opendaylight.controller.cluster.raft.messages.AppendEntriesReply;
  40 import org.opendaylight.controller.cluster.raft.messages.RaftRPC;
  41 import org.opendaylight.controller.cluster.raft.messages.RequestVote;
  42 import org.opendaylight.controller.cluster.raft.messages.RequestVoteReply;
  43 import org.opendaylight.controller.cluster.raft.persisted.SimpleReplicatedLogEntry;
  44 import org.opendaylight.controller.cluster.raft.utils.MessageCollectorActor;
  45 import org.slf4j.Logger;
  46 import org.slf4j.LoggerFactory;
  47
  48 public class CandidateTest extends AbstractRaftActorBehaviorTest<Candidate> {
  49     static final Logger LOG = LoggerFactory.getLogger(CandidateTest.class);
  50
  51     private final TestActorRef<MessageCollectorActor> candidateActor = actorFactory.createTestActor(
  52             MessageCollectorActor.props().withDispatcher(Dispatchers.DefaultDispatcherId()),
  53             actorFactory.generateActorId("candidate"));
  54
  55     private ActorRef[] peerActors;
  56
  57     private RaftActorBehavior candidate;
  58
  59     @Before
  60     public void setUp(){
  61     }
  62
  63     @Override
  64     @After
  65     public void tearDown() {
  66         if (candidate != null) {
  67             candidate.close();
  68         }
  69
  70         super.tearDown();
  71     }
  72
  73     @Test
  74     public void testWhenACandidateIsCreatedItIncrementsTheCurrentTermAndVotesForItself() {
  75         RaftActorContext raftActorContext = createActorContext();
  76         long expectedTerm = raftActorContext.getTermInformation().getCurrentTerm();
  77
  78         candidate = new Candidate(raftActorContext);
  79
  80         assertEquals("getCurrentTerm", expectedTerm + 1, raftActorContext.getTermInformation().getCurrentTerm());
  81         assertEquals("getVotedFor", raftActorContext.getId(), raftActorContext.getTermInformation().getVotedFor());
  82     }
  83
  84     @Test
  85     public void testThatAnElectionTimeoutIsTriggered() {
  86         MockRaftActorContext actorContext = createActorContext();
  87         candidate = new Candidate(actorContext);
  88
  89         MessageCollectorActor.expectFirstMatching(candidateActor, ElectionTimeout.class,
  90                 actorContext.getConfigParams().getElectionTimeOutInterval().$times(6).toMillis());
  91     }
  92
  93     @Test
  94     public void testHandleElectionTimeoutWhenThereAreZeroPeers() {
  95         RaftActorContext raftActorContext = createActorContext();
  96         candidate = new Candidate(raftActorContext);
  97
  98         RaftActorBehavior newBehavior =
  99             candidate.handleMessage(candidateActor, ElectionTimeout.INSTANCE);
 100
 101         assertEquals("Behavior", RaftState.Leader, newBehavior.state());
 102     }
 103
 104     @Test
 105     public void testHandleElectionTimeoutWhenThereAreTwoNodeCluster() {
 106         MockRaftActorContext raftActorContext = createActorContext();
 107         raftActorContext.setPeerAddresses(setupPeers(1));
 108         candidate = new Candidate(raftActorContext);
 109
 110         candidate = candidate.handleMessage(candidateActor, ElectionTimeout.INSTANCE);
 111
 112         assertEquals("Behavior", RaftState.Candidate, candidate.state());
 113     }
 114
 115     @Test
 116     public void testBecomeLeaderOnReceivingMajorityVotesInThreeNodeCluster() {
 117         MockRaftActorContext raftActorContext = createActorContext();
 118         raftActorContext.setLastApplied(raftActorContext.getReplicatedLog().lastIndex());
 119         raftActorContext.setPeerAddresses(setupPeers(2));
 120         candidate = new Candidate(raftActorContext);
 121
 122         candidate = candidate.handleMessage(peerActors[0], new RequestVoteReply(1, true));
 123
 124         assertEquals("Behavior", RaftState.Leader, candidate.state());
 125     }
 126
 127     @Test
 128     public void testBecomePreLeaderOnReceivingMajorityVotesInThreeNodeCluster() {
 129         MockRaftActorContext raftActorContext = createActorContext();
 130         raftActorContext.setLastApplied(-1);
 131         raftActorContext.setPeerAddresses(setupPeers(2));
 132         candidate = new Candidate(raftActorContext);
 133
 134         candidate = candidate.handleMessage(peerActors[0], new RequestVoteReply(1, true));
 135
 136         // LastApplied is -1 and behind the last index.
 137         assertEquals("Behavior", RaftState.PreLeader, candidate.state());
 138     }
 139
 140     @Test
 141     public void testBecomeLeaderOnReceivingMajorityVotesInFiveNodeCluster() {
 142         MockRaftActorContext raftActorContext = createActorContext();
 143         raftActorContext.getTermInformation().update(2L, "other");
 144         raftActorContext.setReplicatedLog(new MockRaftActorContext.MockReplicatedLogBuilder()
 145                 .createEntries(0, 5, 1).build());
 146         raftActorContext.setCommitIndex(raftActorContext.getReplicatedLog().lastIndex());
 147         raftActorContext.setLastApplied(raftActorContext.getReplicatedLog().lastIndex());
 148         raftActorContext.setPeerAddresses(setupPeers(4));
 149         candidate = new Candidate(raftActorContext);
 150
 151         RequestVote requestVote = MessageCollectorActor.expectFirstMatching(peerActors[0], RequestVote.class);
 152         assertEquals("getTerm", 3L, requestVote.getTerm());
 153         assertEquals("getCandidateId", raftActorContext.getId(), requestVote.getCandidateId());
 154         assertEquals("getLastLogTerm", 1L, requestVote.getLastLogTerm());
 155         assertEquals("getLastLogIndex", 4L, requestVote.getLastLogIndex());
 156
 157         MessageCollectorActor.expectFirstMatching(peerActors[1], RequestVote.class);
 158         MessageCollectorActor.expectFirstMatching(peerActors[2], RequestVote.class);
 159         MessageCollectorActor.expectFirstMatching(peerActors[3], RequestVote.class);
 160
 161         // First peers denies the vote.
 162         candidate = candidate.handleMessage(peerActors[0], new RequestVoteReply(1, false));
 163
 164         assertEquals("Behavior", RaftState.Candidate, candidate.state());
 165
 166         candidate = candidate.handleMessage(peerActors[1], new RequestVoteReply(1, true));
 167
 168         assertEquals("Behavior", RaftState.Candidate, candidate.state());
 169
 170         candidate = candidate.handleMessage(peerActors[2], new RequestVoteReply(1, true));
 171
 172         assertEquals("Behavior", RaftState.Leader, candidate.state());
 173     }
 174
 175     @Test
 176     public void testBecomeLeaderOnReceivingMajorityVotesWithNonVotingPeers() {
 177         ElectionTerm mockElectionTerm = Mockito.mock(ElectionTerm.class);
 178         Mockito.doReturn(1L).when(mockElectionTerm).getCurrentTerm();
 179         RaftActorContext raftActorContext = new RaftActorContextImpl(candidateActor, candidateActor.actorContext(),
 180                 "candidate", mockElectionTerm, -1, -1, setupPeers(4), new DefaultConfigParamsImpl(),
 181                 new NonPersistentDataProvider(Runnable::run), applyState -> { }, LOG);
 182         raftActorContext.setReplicatedLog(new MockRaftActorContext.MockReplicatedLogBuilder().build());
 183         raftActorContext.getPeerInfo("peer1").setVotingState(VotingState.NON_VOTING);
 184         raftActorContext.getPeerInfo("peer4").setVotingState(VotingState.NON_VOTING);
 185         candidate = new Candidate(raftActorContext);
 186
 187         MessageCollectorActor.expectFirstMatching(peerActors[1], RequestVote.class);
 188         MessageCollectorActor.expectFirstMatching(peerActors[2], RequestVote.class);
 189         MessageCollectorActor.assertNoneMatching(peerActors[0], RequestVote.class, 300);
 190         MessageCollectorActor.assertNoneMatching(peerActors[3], RequestVote.class, 100);
 191
 192         candidate = candidate.handleMessage(peerActors[1], new RequestVoteReply(1, false));
 193
 194         assertEquals("Behavior", RaftState.Candidate, candidate.state());
 195
 196         candidate = candidate.handleMessage(peerActors[2], new RequestVoteReply(1, true));
 197
 198         assertEquals("Behavior", RaftState.Leader, candidate.state());
 199     }
 200
 201     @Test
 202     public void testResponseToHandleAppendEntriesWithLowerTerm() {
 203         candidate = new Candidate(createActorContext());
 204
 205         setupPeers(1);
 206         RaftActorBehavior newBehavior = candidate.handleMessage(peerActors[0], new AppendEntries(1, "test", 0, 0,
 207                 Collections.<ReplicatedLogEntry>emptyList(), 0, -1, (short) 0));
 208
 209         AppendEntriesReply reply = MessageCollectorActor.expectFirstMatching(
 210                 peerActors[0], AppendEntriesReply.class);
 211         assertEquals("isSuccess", false, reply.isSuccess());
 212         assertEquals("getTerm", 2, reply.getTerm());
 213         assertTrue("New Behavior : " + newBehavior, newBehavior instanceof Candidate);
 214     }
 215
 216     @Test
 217     public void testResponseToHandleAppendEntriesWithHigherTerm() {
 218         candidate = new Candidate(createActorContext());
 219
 220         setupPeers(1);
 221         RaftActorBehavior newBehavior = candidate.handleMessage(peerActors[0], new AppendEntries(5, "test", 0, 0,
 222                 Collections.<ReplicatedLogEntry>emptyList(), 0, -1, (short) 0));
 223
 224         assertTrue("New Behavior : " + newBehavior, newBehavior instanceof Follower);
 225     }
 226
 227     @Test
 228     public void testResponseToHandleAppendEntriesWithEqualTerm() {
 229         MockRaftActorContext actorContext = createActorContext();
 230
 231         candidate = new Candidate(actorContext);
 232
 233         setupPeers(1);
 234         RaftActorBehavior newBehavior = candidate.handleMessage(peerActors[0], new AppendEntries(2, "test", 0, 0,
 235                 Collections.<ReplicatedLogEntry>emptyList(), 0, -1, (short) 0));
 236
 237         assertTrue("New Behavior : " + newBehavior + " term = " + actorContext.getTermInformation().getCurrentTerm(),
 238                 newBehavior instanceof Follower);
 239     }
 240
 241
 242     @Test
 243     public void testResponseToRequestVoteWithLowerTerm() {
 244         candidate = new Candidate(createActorContext());
 245
 246         setupPeers(1);
 247         candidate.handleMessage(peerActors[0], new RequestVote(1, "test", 0, 0));
 248
 249         RequestVoteReply reply = MessageCollectorActor.expectFirstMatching(
 250                 peerActors[0], RequestVoteReply.class);
 251         assertEquals("isVoteGranted", false, reply.isVoteGranted());
 252         assertEquals("getTerm", 2, reply.getTerm());
 253     }
 254
 255     @Test
 256     public void testHandleRequestVoteWhenSenderTermEqualToCurrentTermAndVotedForMatches() {
 257         MockRaftActorContext context = createActorContext();
 258         context.getTermInformation().update(1000, null);
 259
 260         // Once a candidate is created it will immediately increment the current term so after
 261         // construction the currentTerm should be 1001
 262         candidate = new Candidate(context);
 263
 264         setupPeers(1);
 265         candidate.handleMessage(peerActors[0], new RequestVote(1001, context.getId(), 10000, 999));
 266
 267         RequestVoteReply reply = MessageCollectorActor.expectFirstMatching(
 268                 peerActors[0], RequestVoteReply.class);
 269         assertEquals("isVoteGranted", true, reply.isVoteGranted());
 270         assertEquals("getTerm", 1001, reply.getTerm());
 271     }
 272
 273     @Test
 274     public void testHandleRequestVoteWhenSenderTermEqualToCurrentTermAndVotedForDoesNotMatch() {
 275         MockRaftActorContext context = createActorContext();
 276         context.getTermInformation().update(1000, null);
 277
 278         // Once a candidate is created it will immediately increment the current term so after
 279         // construction the currentTerm should be 1001
 280         candidate = new Candidate(context);
 281
 282         setupPeers(1);
 283
 284         // RequestVote candidate ID ("candidate2") does not match this candidate's votedFor
 285         // (it votes for itself)
 286         candidate.handleMessage(peerActors[0], new RequestVote(1001, "candidate2", 10000, 999));
 287
 288         RequestVoteReply reply = MessageCollectorActor.expectFirstMatching(
 289                 peerActors[0], RequestVoteReply.class);
 290         assertEquals("isVoteGranted", false, reply.isVoteGranted());
 291         assertEquals("getTerm", 1001, reply.getTerm());
 292     }
 293
 294     @Test
 295     public void testCandidateSchedulesElectionTimeoutImmediatelyWhenItHasNoPeers() {
 296         MockRaftActorContext context = createActorContext();
 297
 298         Stopwatch stopwatch = Stopwatch.createStarted();
 299
 300         candidate = createBehavior(context);
 301
 302         MessageCollectorActor.expectFirstMatching(candidateActor, ElectionTimeout.class);
 303
 304         long elapsed = stopwatch.elapsed(TimeUnit.MILLISECONDS);
 305
 306         assertTrue(elapsed < context.getConfigParams().getElectionTimeOutInterval().toMillis());
 307     }
 308
 309     @Test
 310     @Override
 311     public void testHandleAppendEntriesAddSameEntryToLog() {
 312         MockRaftActorContext context = createActorContext();
 313
 314         context.getTermInformation().update(2, "test");
 315
 316         // Prepare the receivers log
 317         MockRaftActorContext.MockPayload payload = new MockRaftActorContext.MockPayload("zero");
 318         setLastLogEntry(context, 2, 0, payload);
 319
 320         List<ReplicatedLogEntry> entries = new ArrayList<>();
 321         entries.add(new SimpleReplicatedLogEntry(0, 2, payload));
 322
 323         final AppendEntries appendEntries = new AppendEntries(2, "leader-1", -1, -1, entries, 2, -1, (short)0);
 324
 325         behavior = createBehavior(context);
 326
 327         // Resetting the Candidates term to make sure it will match
 328         // the term sent by AppendEntries. If this was not done then
 329         // the test will fail because the Candidate will assume that
 330         // the message was sent to it from a lower term peer and will
 331         // thus respond with a failure
 332         context.getTermInformation().update(2, "test");
 333
 334         // Send an unknown message so that the state of the RaftActor remains unchanged
 335         behavior.handleMessage(candidateActor, "unknown");
 336
 337         RaftActorBehavior raftBehavior = behavior.handleMessage(candidateActor, appendEntries);
 338
 339         assertEquals("Raft state", RaftState.Follower, raftBehavior.state());
 340
 341         assertEquals("ReplicatedLog size", 1, context.getReplicatedLog().size());
 342
 343         handleAppendEntriesAddSameEntryToLogReply(candidateActor);
 344     }
 345
 346     @Override
 347     protected Candidate createBehavior(final RaftActorContext actorContext) {
 348         return new Candidate(actorContext);
 349     }
 350
 351     @Override
 352     protected MockRaftActorContext createActorContext() {
 353         return new MockRaftActorContext("candidate", getSystem(), candidateActor);
 354     }
 355
 356     private Map<String, String> setupPeers(final int count) {
 357         Map<String, String> peerMap = new HashMap<>();
 358         peerActors = new ActorRef[count];
 359         for (int i = 0; i < count; i++) {
 360             peerActors[i] = actorFactory.createActor(MessageCollectorActor.props(),
 361                     actorFactory.generateActorId("peer"));
 362             peerMap.put("peer" + (i + 1), peerActors[i].path().toString());
 363         }
 364
 365         return peerMap;
 366     }
 367
 368     @Override
 369     protected void assertStateChangesToFollowerWhenRaftRPCHasNewerTerm(final MockRaftActorContext actorContext,
 370             final ActorRef actorRef, final RaftRPC rpc) {
 371         super.assertStateChangesToFollowerWhenRaftRPCHasNewerTerm(actorContext, actorRef, rpc);
 372         if (rpc instanceof RequestVote) {
 373             assertEquals("New votedFor", ((RequestVote)rpc).getCandidateId(),
 374                     actorContext.getTermInformation().getVotedFor());
 375         } else {
 376             assertEquals("New votedFor", null, actorContext.getTermInformation().getVotedFor());
 377         }
 378     }
 379 }