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 com.google.common.util.concurrent.MoreExecutors;
  19 import java.util.ArrayList;
  20 import java.util.Collections;
  21 import java.util.HashMap;
  22 import java.util.List;
  23 import java.util.Map;
  24 import java.util.concurrent.TimeUnit;
  25 import org.junit.After;
  26 import org.junit.Before;
  27 import org.junit.Test;
  28 import org.mockito.Mockito;
  29 import org.opendaylight.controller.cluster.NonPersistentDataProvider;
  30 import org.opendaylight.controller.cluster.raft.DefaultConfigParamsImpl;
  31 import org.opendaylight.controller.cluster.raft.ElectionTerm;
  32 import org.opendaylight.controller.cluster.raft.MockRaftActorContext;
  33 import org.opendaylight.controller.cluster.raft.RaftActorContext;
  34 import org.opendaylight.controller.cluster.raft.RaftActorContextImpl;
  35 import org.opendaylight.controller.cluster.raft.RaftState;
  36 import org.opendaylight.controller.cluster.raft.ReplicatedLogEntry;
  37 import org.opendaylight.controller.cluster.raft.VotingState;
  38 import org.opendaylight.controller.cluster.raft.base.messages.ElectionTimeout;
  39 import org.opendaylight.controller.cluster.raft.messages.AppendEntries;
  40 import org.opendaylight.controller.cluster.raft.messages.AppendEntriesReply;
  41 import org.opendaylight.controller.cluster.raft.messages.RaftRPC;
  42 import org.opendaylight.controller.cluster.raft.messages.RequestVote;
  43 import org.opendaylight.controller.cluster.raft.messages.RequestVoteReply;
  44 import org.opendaylight.controller.cluster.raft.persisted.SimpleReplicatedLogEntry;
  45 import org.opendaylight.controller.cluster.raft.utils.MessageCollectorActor;
  46 import org.slf4j.Logger;
  47 import org.slf4j.LoggerFactory;
  48
  49 public class CandidateTest extends AbstractRaftActorBehaviorTest<Candidate> {
  50     static final Logger LOG = LoggerFactory.getLogger(CandidateTest.class);
  51
  52     private final TestActorRef<MessageCollectorActor> candidateActor = actorFactory.createTestActor(
  53             MessageCollectorActor.props().withDispatcher(Dispatchers.DefaultDispatcherId()),
  54             actorFactory.generateActorId("candidate"));
  55
  56     private ActorRef[] peerActors;
  57
  58     private RaftActorBehavior candidate;
  59
  60     @Before
  61     public void setUp(){
  62     }
  63
  64     @Override
  65     @After
  66     public void tearDown() {
  67         if (candidate != null) {
  68             candidate.close();
  69         }
  70
  71         super.tearDown();
  72     }
  73
  74     @Test
  75     public void testWhenACandidateIsCreatedItIncrementsTheCurrentTermAndVotesForItself() {
  76         RaftActorContext raftActorContext = createActorContext();
  77         long expectedTerm = raftActorContext.getTermInformation().getCurrentTerm();
  78
  79         candidate = new Candidate(raftActorContext);
  80
  81         assertEquals("getCurrentTerm", expectedTerm + 1, raftActorContext.getTermInformation().getCurrentTerm());
  82         assertEquals("getVotedFor", raftActorContext.getId(), raftActorContext.getTermInformation().getVotedFor());
  83     }
  84
  85     @Test
  86     public void testThatAnElectionTimeoutIsTriggered() {
  87         MockRaftActorContext actorContext = createActorContext();
  88         candidate = new Candidate(actorContext);
  89
  90         MessageCollectorActor.expectFirstMatching(candidateActor, ElectionTimeout.class,
  91                 actorContext.getConfigParams().getElectionTimeOutInterval().$times(6).toMillis());
  92     }
  93
  94     @Test
  95     public void testHandleElectionTimeoutWhenThereAreZeroPeers() {
  96         RaftActorContext raftActorContext = createActorContext();
  97         candidate = new Candidate(raftActorContext);
  98
  99         RaftActorBehavior newBehavior =
 100             candidate.handleMessage(candidateActor, ElectionTimeout.INSTANCE);
 101
 102         assertEquals("Behavior", RaftState.Leader, newBehavior.state());
 103     }
 104
 105     @Test
 106     public void testHandleElectionTimeoutWhenThereAreTwoNodeCluster() {
 107         MockRaftActorContext raftActorContext = createActorContext();
 108         raftActorContext.setPeerAddresses(setupPeers(1));
 109         candidate = new Candidate(raftActorContext);
 110
 111         candidate = candidate.handleMessage(candidateActor, ElectionTimeout.INSTANCE);
 112
 113         assertEquals("Behavior", RaftState.Candidate, candidate.state());
 114     }
 115
 116     @Test
 117     public void testBecomeLeaderOnReceivingMajorityVotesInThreeNodeCluster() {
 118         MockRaftActorContext raftActorContext = createActorContext();
 119         raftActorContext.setLastApplied(raftActorContext.getReplicatedLog().lastIndex());
 120         raftActorContext.setPeerAddresses(setupPeers(2));
 121         candidate = new Candidate(raftActorContext);
 122
 123         candidate = candidate.handleMessage(peerActors[0], new RequestVoteReply(1, true));
 124
 125         assertEquals("Behavior", RaftState.Leader, candidate.state());
 126     }
 127
 128     @Test
 129     public void testBecomePreLeaderOnReceivingMajorityVotesInThreeNodeCluster() {
 130         MockRaftActorContext raftActorContext = createActorContext();
 131         raftActorContext.setLastApplied(-1);
 132         raftActorContext.setPeerAddresses(setupPeers(2));
 133         candidate = new Candidate(raftActorContext);
 134
 135         candidate = candidate.handleMessage(peerActors[0], new RequestVoteReply(1, true));
 136
 137         // LastApplied is -1 and behind the last index.
 138         assertEquals("Behavior", RaftState.PreLeader, candidate.state());
 139     }
 140
 141     @Test
 142     public void testBecomeLeaderOnReceivingMajorityVotesInFiveNodeCluster() {
 143         MockRaftActorContext raftActorContext = createActorContext();
 144         raftActorContext.getTermInformation().update(2L, "other");
 145         raftActorContext.setReplicatedLog(new MockRaftActorContext.MockReplicatedLogBuilder()
 146                 .createEntries(0, 5, 1).build());
 147         raftActorContext.setCommitIndex(raftActorContext.getReplicatedLog().lastIndex());
 148         raftActorContext.setLastApplied(raftActorContext.getReplicatedLog().lastIndex());
 149         raftActorContext.setPeerAddresses(setupPeers(4));
 150         candidate = new Candidate(raftActorContext);
 151
 152         RequestVote requestVote = MessageCollectorActor.expectFirstMatching(peerActors[0], RequestVote.class);
 153         assertEquals("getTerm", 3L, requestVote.getTerm());
 154         assertEquals("getCandidateId", raftActorContext.getId(), requestVote.getCandidateId());
 155         assertEquals("getLastLogTerm", 1L, requestVote.getLastLogTerm());
 156         assertEquals("getLastLogIndex", 4L, requestVote.getLastLogIndex());
 157
 158         MessageCollectorActor.expectFirstMatching(peerActors[1], RequestVote.class);
 159         MessageCollectorActor.expectFirstMatching(peerActors[2], RequestVote.class);
 160         MessageCollectorActor.expectFirstMatching(peerActors[3], RequestVote.class);
 161
 162         // First peers denies the vote.
 163         candidate = candidate.handleMessage(peerActors[0], new RequestVoteReply(1, false));
 164
 165         assertEquals("Behavior", RaftState.Candidate, candidate.state());
 166
 167         candidate = candidate.handleMessage(peerActors[1], new RequestVoteReply(1, true));
 168
 169         assertEquals("Behavior", RaftState.Candidate, candidate.state());
 170
 171         candidate = candidate.handleMessage(peerActors[2], new RequestVoteReply(1, true));
 172
 173         assertEquals("Behavior", RaftState.Leader, candidate.state());
 174     }
 175
 176     @Test
 177     public void testBecomeLeaderOnReceivingMajorityVotesWithNonVotingPeers() {
 178         ElectionTerm mockElectionTerm = Mockito.mock(ElectionTerm.class);
 179         Mockito.doReturn(1L).when(mockElectionTerm).getCurrentTerm();
 180         RaftActorContext raftActorContext = new RaftActorContextImpl(candidateActor, candidateActor.actorContext(),
 181                 "candidate", mockElectionTerm, -1, -1, setupPeers(4), new DefaultConfigParamsImpl(),
 182                 new NonPersistentDataProvider(Runnable::run), applyState -> { }, LOG,  MoreExecutors.directExecutor());
 183         raftActorContext.setReplicatedLog(new MockRaftActorContext.MockReplicatedLogBuilder().build());
 184         raftActorContext.getPeerInfo("peer1").setVotingState(VotingState.NON_VOTING);
 185         raftActorContext.getPeerInfo("peer4").setVotingState(VotingState.NON_VOTING);
 186         candidate = new Candidate(raftActorContext);
 187
 188         MessageCollectorActor.expectFirstMatching(peerActors[1], RequestVote.class);
 189         MessageCollectorActor.expectFirstMatching(peerActors[2], RequestVote.class);
 190         MessageCollectorActor.assertNoneMatching(peerActors[0], RequestVote.class, 300);
 191         MessageCollectorActor.assertNoneMatching(peerActors[3], RequestVote.class, 100);
 192
 193         candidate = candidate.handleMessage(peerActors[1], new RequestVoteReply(1, false));
 194
 195         assertEquals("Behavior", RaftState.Candidate, candidate.state());
 196
 197         candidate = candidate.handleMessage(peerActors[2], new RequestVoteReply(1, true));
 198
 199         assertEquals("Behavior", RaftState.Leader, candidate.state());
 200     }
 201
 202     @Test
 203     public void testResponseToHandleAppendEntriesWithLowerTerm() {
 204         candidate = new Candidate(createActorContext());
 205
 206         setupPeers(1);
 207         RaftActorBehavior newBehavior = candidate.handleMessage(peerActors[0], new AppendEntries(1, "test", 0, 0,
 208                 Collections.<ReplicatedLogEntry>emptyList(), 0, -1, (short) 0));
 209
 210         AppendEntriesReply reply = MessageCollectorActor.expectFirstMatching(
 211                 peerActors[0], AppendEntriesReply.class);
 212         assertEquals("isSuccess", false, reply.isSuccess());
 213         assertEquals("getTerm", 2, reply.getTerm());
 214         assertTrue("New Behavior : " + newBehavior, newBehavior instanceof Candidate);
 215     }
 216
 217     @Test
 218     public void testResponseToHandleAppendEntriesWithHigherTerm() {
 219         candidate = new Candidate(createActorContext());
 220
 221         setupPeers(1);
 222         RaftActorBehavior newBehavior = candidate.handleMessage(peerActors[0], new AppendEntries(5, "test", 0, 0,
 223                 Collections.<ReplicatedLogEntry>emptyList(), 0, -1, (short) 0));
 224
 225         assertTrue("New Behavior : " + newBehavior, newBehavior instanceof Follower);
 226     }
 227
 228     @Test
 229     public void testResponseToHandleAppendEntriesWithEqualTerm() {
 230         MockRaftActorContext actorContext = createActorContext();
 231
 232         candidate = new Candidate(actorContext);
 233
 234         setupPeers(1);
 235         RaftActorBehavior newBehavior = candidate.handleMessage(peerActors[0], new AppendEntries(2, "test", 0, 0,
 236                 Collections.<ReplicatedLogEntry>emptyList(), 0, -1, (short) 0));
 237
 238         assertTrue("New Behavior : " + newBehavior + " term = " + actorContext.getTermInformation().getCurrentTerm(),
 239                 newBehavior instanceof Follower);
 240     }
 241
 242
 243     @Test
 244     public void testResponseToRequestVoteWithLowerTerm() {
 245         candidate = new Candidate(createActorContext());
 246
 247         setupPeers(1);
 248         candidate.handleMessage(peerActors[0], new RequestVote(1, "test", 0, 0));
 249
 250         RequestVoteReply reply = MessageCollectorActor.expectFirstMatching(
 251                 peerActors[0], RequestVoteReply.class);
 252         assertEquals("isVoteGranted", false, reply.isVoteGranted());
 253         assertEquals("getTerm", 2, reply.getTerm());
 254     }
 255
 256     @Test
 257     public void testHandleRequestVoteWhenSenderTermEqualToCurrentTermAndVotedForMatches() {
 258         MockRaftActorContext context = createActorContext();
 259         context.getTermInformation().update(1000, null);
 260
 261         // Once a candidate is created it will immediately increment the current term so after
 262         // construction the currentTerm should be 1001
 263         candidate = new Candidate(context);
 264
 265         setupPeers(1);
 266         candidate.handleMessage(peerActors[0], new RequestVote(1001, context.getId(), 10000, 999));
 267
 268         RequestVoteReply reply = MessageCollectorActor.expectFirstMatching(
 269                 peerActors[0], RequestVoteReply.class);
 270         assertEquals("isVoteGranted", true, reply.isVoteGranted());
 271         assertEquals("getTerm", 1001, reply.getTerm());
 272     }
 273
 274     @Test
 275     public void testHandleRequestVoteWhenSenderTermEqualToCurrentTermAndVotedForDoesNotMatch() {
 276         MockRaftActorContext context = createActorContext();
 277         context.getTermInformation().update(1000, null);
 278
 279         // Once a candidate is created it will immediately increment the current term so after
 280         // construction the currentTerm should be 1001
 281         candidate = new Candidate(context);
 282
 283         setupPeers(1);
 284
 285         // RequestVote candidate ID ("candidate2") does not match this candidate's votedFor
 286         // (it votes for itself)
 287         candidate.handleMessage(peerActors[0], new RequestVote(1001, "candidate2", 10000, 999));
 288
 289         RequestVoteReply reply = MessageCollectorActor.expectFirstMatching(
 290                 peerActors[0], RequestVoteReply.class);
 291         assertEquals("isVoteGranted", false, reply.isVoteGranted());
 292         assertEquals("getTerm", 1001, reply.getTerm());
 293     }
 294
 295     @Test
 296     public void testCandidateSchedulesElectionTimeoutImmediatelyWhenItHasNoPeers() {
 297         MockRaftActorContext context = createActorContext();
 298
 299         Stopwatch stopwatch = Stopwatch.createStarted();
 300
 301         candidate = createBehavior(context);
 302
 303         MessageCollectorActor.expectFirstMatching(candidateActor, ElectionTimeout.class);
 304
 305         long elapsed = stopwatch.elapsed(TimeUnit.MILLISECONDS);
 306
 307         assertTrue(elapsed < context.getConfigParams().getElectionTimeOutInterval().toMillis());
 308     }
 309
 310     @Test
 311     @Override
 312     public void testHandleAppendEntriesAddSameEntryToLog() {
 313         MockRaftActorContext context = createActorContext();
 314
 315         context.getTermInformation().update(2, "test");
 316
 317         // Prepare the receivers log
 318         MockRaftActorContext.MockPayload payload = new MockRaftActorContext.MockPayload("zero");
 319         setLastLogEntry(context, 2, 0, payload);
 320
 321         List<ReplicatedLogEntry> entries = new ArrayList<>();
 322         entries.add(new SimpleReplicatedLogEntry(0, 2, payload));
 323
 324         final AppendEntries appendEntries = new AppendEntries(2, "leader-1", -1, -1, entries, 2, -1, (short)0);
 325
 326         behavior = createBehavior(context);
 327
 328         // Resetting the Candidates term to make sure it will match
 329         // the term sent by AppendEntries. If this was not done then
 330         // the test will fail because the Candidate will assume that
 331         // the message was sent to it from a lower term peer and will
 332         // thus respond with a failure
 333         context.getTermInformation().update(2, "test");
 334
 335         // Send an unknown message so that the state of the RaftActor remains unchanged
 336         behavior.handleMessage(candidateActor, "unknown");
 337
 338         RaftActorBehavior raftBehavior = behavior.handleMessage(candidateActor, appendEntries);
 339
 340         assertEquals("Raft state", RaftState.Follower, raftBehavior.state());
 341
 342         assertEquals("ReplicatedLog size", 1, context.getReplicatedLog().size());
 343
 344         handleAppendEntriesAddSameEntryToLogReply(candidateActor);
 345     }
 346
 347     @Override
 348     protected Candidate createBehavior(final RaftActorContext actorContext) {
 349         return new Candidate(actorContext);
 350     }
 351
 352     @Override
 353     protected MockRaftActorContext createActorContext() {
 354         return new MockRaftActorContext("candidate", getSystem(), candidateActor);
 355     }
 356
 357     private Map<String, String> setupPeers(final int count) {
 358         Map<String, String> peerMap = new HashMap<>();
 359         peerActors = new ActorRef[count];
 360         for (int i = 0; i < count; i++) {
 361             peerActors[i] = actorFactory.createActor(MessageCollectorActor.props(),
 362                     actorFactory.generateActorId("peer"));
 363             peerMap.put("peer" + (i + 1), peerActors[i].path().toString());
 364         }
 365
 366         return peerMap;
 367     }
 368
 369     @Override
 370     protected void assertStateChangesToFollowerWhenRaftRPCHasNewerTerm(final MockRaftActorContext actorContext,
 371             final ActorRef actorRef, final RaftRPC rpc) {
 372         super.assertStateChangesToFollowerWhenRaftRPCHasNewerTerm(actorContext, actorRef, rpc);
 373         if (rpc instanceof RequestVote) {
 374             assertEquals("New votedFor", ((RequestVote)rpc).getCandidateId(),
 375                     actorContext.getTermInformation().getVotedFor());
 376         } else {
 377             assertEquals("New votedFor", null, actorContext.getTermInformation().getVotedFor());
 378         }
 379     }
 380 }