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