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