2 * Copyright (c) 2015 Brocade Communications Systems, Inc. and others. All rights reserved.
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
8 package org.opendaylight.controller.cluster.raft.behaviors;
10 import static org.junit.Assert.assertEquals;
12 import akka.actor.ActorRef;
13 import com.google.common.collect.ImmutableMap;
14 import org.junit.Test;
15 import org.opendaylight.controller.cluster.raft.DefaultConfigParamsImpl;
16 import org.opendaylight.controller.cluster.raft.MockRaftActorContext.MockPayload;
17 import org.opendaylight.controller.cluster.raft.MockRaftActorContext.SimpleReplicatedLog;
18 import org.opendaylight.controller.cluster.raft.RaftState;
19 import org.opendaylight.controller.cluster.raft.base.messages.ElectionTimeout;
20 import org.opendaylight.controller.cluster.raft.base.messages.TimeoutNow;
21 import org.opendaylight.controller.cluster.raft.messages.RequestVote;
22 import org.opendaylight.controller.cluster.raft.messages.RequestVoteReply;
23 import org.opendaylight.controller.cluster.raft.persisted.SimpleReplicatedLogEntry;
26 * A leader election scenario test that partitions a candidate when trying to join a cluster on startup.
28 * @author Thomas Pantelis
30 public class PartitionedCandidateOnStartupElectionScenarioTest extends AbstractLeaderElectionScenarioTest {
32 private final int numCandidateElections = 5;
33 private long candidateElectionTerm;
36 public void runTest() {
37 testLog.info("PartitionedCandidateOnStartupElectionScenarioTest starting");
39 setupInitialMember1AndMember2Behaviors();
41 setupPartitionedCandidateMember3AndSendElectionTimeouts();
43 resolvePartitionAndSendElectionTimeoutsToCandidateMember3();
45 sendElectionTimeoutToFollowerMember1();
47 testLog.info("PartitionedCandidateOnStartupElectionScenarioTest ending");
50 private void sendElectionTimeoutToFollowerMember1() {
51 testLog.info("sendElectionTimeoutToFollowerMember1 starting");
53 // At this point we have no leader. Candidate member 3 would continue to start new elections
54 // but wouldn't be granted a vote. One of the 2 followers would eventually time out from
55 // not having received a heartbeat from a leader and switch to candidate and start a new
56 // election. We'll simulate that here by sending an ElectionTimeout to member 1.
59 member1Actor.expectMessageClass(RequestVoteReply.class, 1);
61 member2Actor.expectMessageClass(RequestVote.class, 1);
63 member3Actor.expectMessageClass(RequestVote.class, 1);
64 member3Actor.expectBehaviorStateChange();
66 member1ActorRef.tell(TimeoutNow.INSTANCE, ActorRef.noSender());
68 member2Actor.waitForExpectedMessages(RequestVote.class);
69 member3Actor.waitForExpectedMessages(RequestVote.class);
71 // The RequestVoteReply should come from Follower member 2 and the vote should be granted
72 // since member 2's last term and index matches member 1's.
74 member1Actor.waitForExpectedMessages(RequestVoteReply.class);
76 RequestVoteReply requestVoteReply = member1Actor.getCapturedMessage(RequestVoteReply.class);
77 assertEquals("getTerm", member1Context.getTermInformation().getCurrentTerm(), requestVoteReply.getTerm());
78 assertEquals("isVoteGranted", true, requestVoteReply.isVoteGranted());
80 // Candidate member 3 should change to follower as its term should be less than the
81 // RequestVote term (member 1 started a new term higher than the other member's terms).
83 member3Actor.waitForBehaviorStateChange();
85 verifyBehaviorState("member 1", member1Actor, RaftState.Leader);
86 verifyBehaviorState("member 2", member2Actor, RaftState.Follower);
87 verifyBehaviorState("member 3", member3Actor, RaftState.Follower);
89 // newTerm should be 10.
91 long newTerm = candidateElectionTerm + 1;
92 assertEquals("member 1 election term", newTerm, member1Context.getTermInformation().getCurrentTerm());
93 assertEquals("member 2 election term", newTerm, member2Context.getTermInformation().getCurrentTerm());
94 assertEquals("member 3 election term", newTerm, member3Context.getTermInformation().getCurrentTerm());
96 testLog.info("sendElectionTimeoutToFollowerMember1 ending");
99 private void resolvePartitionAndSendElectionTimeoutsToCandidateMember3() {
100 testLog.info("resolvePartitionAndSendElectionTimeoutsToCandidateMember3 starting");
102 // Now send a couple more ElectionTimeouts to Candidate member 3 with the partition resolved.
104 // On the first RequestVote, Leader member 1 should switch to Follower as its term (s) is less than
105 // the RequestVote's term (8) from member 3. No RequestVoteReply should be sent by member 1.
106 // Follower member 2 should update its term since it less than the RequestVote's term and
107 // should return a RequestVoteReply but should not grant the vote as its last term and index
108 // is greater than the RequestVote's lastLogTerm and lastLogIndex, ie member 2's log is later
109 // or more up to date than member 3's.
111 // On the second RequestVote, both member 1 and 2 are followers so they should update their
112 // term and return a RequestVoteReply but should not grant the vote.
114 candidateElectionTerm += 2;
115 for (int i = 0; i < 2; i++) {
116 member1Actor.clear();
117 member1Actor.expectMessageClass(RequestVote.class, 1);
118 member2Actor.clear();
119 member2Actor.expectMessageClass(RequestVote.class, 1);
120 member3Actor.clear();
121 member3Actor.expectMessageClass(RequestVoteReply.class, 1);
123 member3ActorRef.tell(ElectionTimeout.INSTANCE, ActorRef.noSender());
125 member1Actor.waitForExpectedMessages(RequestVote.class);
126 member2Actor.waitForExpectedMessages(RequestVote.class);
128 member3Actor.waitForExpectedMessages(RequestVoteReply.class);
130 RequestVoteReply requestVoteReply = member3Actor.getCapturedMessage(RequestVoteReply.class);
131 assertEquals("getTerm", member3Context.getTermInformation().getCurrentTerm(), requestVoteReply.getTerm());
132 assertEquals("isVoteGranted", false, requestVoteReply.isVoteGranted());
135 verifyBehaviorState("member 1", member1Actor, RaftState.Follower);
136 verifyBehaviorState("member 2", member2Actor, RaftState.Follower);
137 verifyBehaviorState("member 3", member3Actor, RaftState.Candidate);
139 // Even though member 3 didn't get voted for, member 1 and 2 should have updated their term
142 assertEquals("member 1 election term", candidateElectionTerm,
143 member1Context.getTermInformation().getCurrentTerm());
144 assertEquals("member 2 election term", candidateElectionTerm,
145 member2Context.getTermInformation().getCurrentTerm());
146 assertEquals("member 3 election term", candidateElectionTerm,
147 member3Context.getTermInformation().getCurrentTerm());
149 testLog.info("resolvePartitionAndSendElectionTimeoutsToCandidateMember3 ending");
152 private void setupPartitionedCandidateMember3AndSendElectionTimeouts() {
153 testLog.info("setupPartitionedCandidateMember3AndSendElectionTimeouts starting");
155 // Create member 3's behavior initially as a Candidate.
157 member3Context = newRaftActorContext("member3", member3ActorRef,
158 ImmutableMap.<String,String>builder()
159 .put("member1", member1ActorRef.path().toString())
160 .put("member2", member2ActorRef.path().toString()).build());
162 DefaultConfigParamsImpl member3ConfigParams = newConfigParams();
163 member3Context.setConfigParams(member3ConfigParams);
165 // Initialize the ReplicatedLog and election term info for Candidate member 3. The current term
166 // will be 2 and the last term will be 1 so it is behind the leader's log.
168 SimpleReplicatedLog candidateReplicatedLog = new SimpleReplicatedLog();
169 candidateReplicatedLog.append(new SimpleReplicatedLogEntry(0, 2, new MockPayload("")));
171 member3Context.setReplicatedLog(candidateReplicatedLog);
172 member3Context.setCommitIndex(candidateReplicatedLog.lastIndex());
173 member3Context.setLastApplied(candidateReplicatedLog.lastIndex());
174 member3Context.getTermInformation().update(2, member1Context.getId());
176 // The member 3 Candidate will start a new term and send RequestVotes. However it will be
177 // partitioned from the cluster by having member 1 and 2 drop its RequestVote messages.
179 candidateElectionTerm = member3Context.getTermInformation().getCurrentTerm() + numCandidateElections;
181 member1Actor.dropMessagesToBehavior(RequestVote.class, numCandidateElections);
183 member2Actor.dropMessagesToBehavior(RequestVote.class, numCandidateElections);
185 member3Actor.self().tell(new SetBehavior(new Candidate(member3Context), member3Context),
186 ActorRef.noSender());
188 // Send several additional ElectionTimeouts to Candidate member 3. Each ElectionTimeout will
189 // start a new term so Candidate member 3's current term will be greater than the leader's
192 for (int i = 0; i < numCandidateElections - 1; i++) {
193 member3ActorRef.tell(ElectionTimeout.INSTANCE, ActorRef.noSender());
196 member1Actor.waitForExpectedMessages(RequestVote.class);
197 member2Actor.waitForExpectedMessages(RequestVote.class);
199 verifyBehaviorState("member 1", member1Actor, RaftState.Leader);
200 verifyBehaviorState("member 2", member2Actor, RaftState.Follower);
201 verifyBehaviorState("member 3", member3Actor, RaftState.Candidate);
203 assertEquals("member 1 election term", 3, member1Context.getTermInformation().getCurrentTerm());
204 assertEquals("member 2 election term", 3, member2Context.getTermInformation().getCurrentTerm());
205 assertEquals("member 3 election term", candidateElectionTerm,
206 member3Context.getTermInformation().getCurrentTerm());
208 testLog.info("setupPartitionedCandidateMember3AndSendElectionTimeouts ending");
211 private void setupInitialMember1AndMember2Behaviors() {
212 testLog.info("setupInitialMember1AndMember2Behaviors starting");
214 // Initialize the ReplicatedLog and election term info for member 1 and 2. The current term
215 // will be 3 and the last term will be 2.
217 SimpleReplicatedLog replicatedLog = new SimpleReplicatedLog();
218 replicatedLog.append(new SimpleReplicatedLogEntry(0, 2, new MockPayload("")));
219 replicatedLog.append(new SimpleReplicatedLogEntry(1, 3, new MockPayload("")));
221 // Create member 2's behavior as Follower.
223 member2Context = newRaftActorContext("member2", member2ActorRef,
224 ImmutableMap.<String,String>builder()
225 .put("member1", member1ActorRef.path().toString())
226 .put("member3", member3ActorRef.path().toString()).build());
228 DefaultConfigParamsImpl member2ConfigParams = newConfigParams();
229 member2Context.setConfigParams(member2ConfigParams);
231 member2Context.setReplicatedLog(replicatedLog);
232 member2Context.setCommitIndex(replicatedLog.lastIndex());
233 member2Context.setLastApplied(replicatedLog.lastIndex());
234 member2Context.getTermInformation().update(3, "member1");
236 member2Actor.self().tell(new SetBehavior(new Follower(member2Context), member2Context),
237 ActorRef.noSender());
239 // Create member 1's behavior as Leader.
241 member1Context = newRaftActorContext("member1", member1ActorRef,
242 ImmutableMap.<String,String>builder()
243 .put("member2", member2ActorRef.path().toString())
244 .put("member3", member3ActorRef.path().toString()).build());
246 DefaultConfigParamsImpl member1ConfigParams = newConfigParams();
247 member1Context.setConfigParams(member1ConfigParams);
249 member1Context.setReplicatedLog(replicatedLog);
250 member1Context.setCommitIndex(replicatedLog.lastIndex());
251 member1Context.setLastApplied(replicatedLog.lastIndex());
252 member1Context.getTermInformation().update(3, "member1");
254 initializeLeaderBehavior(member1Actor, member1Context, 1);
256 member2Actor.clear();
257 member3Actor.clear();
259 testLog.info("setupInitialMember1AndMember2Behaviors ending");