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