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