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