Examples with ReadableRaftLog org.neo4j.causalclustering.core.consensus.log.ReadableRaftLog used on opensource projects

Example 1 with ReadableRaftLog

use of org.neo4j.causalclustering.core.consensus.log.ReadableRaftLog in project neo4j by neo4j.

the class LeaderTest method leaderShouldNotRespondToSuccessResponseThatIndicatesUpToDateFollower.

@Test
public void leaderShouldNotRespondToSuccessResponseThatIndicatesUpToDateFollower() throws Exception {
    // given
    /*
         * A leader who
         * - has an append index of 100
         * - knows about instance 2
         * - assumes that instance 2 is at an index less than 100 -say 84
         */
    Leader leader = new Leader();
    MemberId instance2 = member(2);
    FollowerState instance2State = createArtificialFollowerState(84);
    ReadableRaftState state = mock(ReadableRaftState.class);
    FollowerStates<MemberId> followerState = new FollowerStates<>();
    followerState = new FollowerStates<>(followerState, instance2, instance2State);
    ReadableRaftLog logMock = mock(ReadableRaftLog.class);
    when(logMock.appendIndex()).thenReturn(100L);
    when(state.commitIndex()).thenReturn(-1L);
    when(state.entryLog()).thenReturn(logMock);
    when(state.followerStates()).thenReturn(followerState);
    // both leader and follower are in the same term
    when(state.term()).thenReturn(4L);
    // when
    // that leader is asked to handle a response from that follower that says that the follower is up to date
    RaftMessages.AppendEntries.Response response = appendEntriesResponse().success().matchIndex(100).term(4).from(instance2).build();
    Outcome outcome = leader.handle(response, state, mock(Log.class));
    // then
    // The leader should not be trying to send any messages to that instance
    assertTrue(outcome.getOutgoingMessages().isEmpty());
    // And the follower state should be updated
    FollowerStates<MemberId> updatedFollowerStates = outcome.getFollowerStates();
    assertEquals(100, updatedFollowerStates.get(instance2).getMatchIndex());
}

Example 2 with ReadableRaftLog

use of org.neo4j.causalclustering.core.consensus.log.ReadableRaftLog in project neo4j by neo4j.

the class LeaderTest method leaderShouldRespondToSuccessResponseThatIndicatesLaggingFollowerWithJustWhatItsMissing.

@Test
public void leaderShouldRespondToSuccessResponseThatIndicatesLaggingFollowerWithJustWhatItsMissing() throws Exception {
    // given
    /*
         * A leader who
         * - has an append index of 100
         * - knows about instance 2
         * - assumes that instance 2 is at an index less than 100 -say 50
         */
    Leader leader = new Leader();
    MemberId instance2 = member(2);
    FollowerState instance2State = createArtificialFollowerState(50);
    ReadableRaftState state = mock(ReadableRaftState.class);
    FollowerStates<MemberId> followerState = new FollowerStates<>();
    followerState = new FollowerStates<>(followerState, instance2, instance2State);
    ReadableRaftLog logMock = mock(ReadableRaftLog.class);
    when(logMock.appendIndex()).thenReturn(100L);
    // with commit requests in this test
    when(state.commitIndex()).thenReturn(-1L);
    when(state.entryLog()).thenReturn(logMock);
    when(state.followerStates()).thenReturn(followerState);
    // both leader and follower are in the same term
    when(state.term()).thenReturn(231L);
    // when that leader is asked to handle a response from that follower that says that the follower is still
    // missing things
    RaftMessages.AppendEntries.Response response = appendEntriesResponse().success().matchIndex(89).term(231).from(instance2).build();
    Outcome outcome = leader.handle(response, state, mock(Log.class));
    // then
    int matchCount = 0;
    for (ShipCommand shipCommand : outcome.getShipCommands()) {
        if (shipCommand instanceof ShipCommand.Match) {
            matchCount++;
        }
    }
    assertThat(matchCount, greaterThan(0));
}

Example 3 with ReadableRaftLog

use of org.neo4j.causalclustering.core.consensus.log.ReadableRaftLog in project neo4j by neo4j.

the class LeaderTest method leaderShouldNotRespondToSuccessResponseFromFollowerThatWillSoonUpToDateViaInFlightMessages.

@Test
public void leaderShouldNotRespondToSuccessResponseFromFollowerThatWillSoonUpToDateViaInFlightMessages() throws Exception {
    // given
    /*
         * A leader who
         * - has an append index of 100
         * - knows about instance 2
         * - assumes that instance 2 is at an index less than 100 -say 84 but it has already been sent up to 100
         */
    Leader leader = new Leader();
    MemberId instance2 = member(2);
    FollowerState instance2State = createArtificialFollowerState(84);
    ReadableRaftState state = mock(ReadableRaftState.class);
    FollowerStates<MemberId> followerState = new FollowerStates<>();
    followerState = new FollowerStates<>(followerState, instance2, instance2State);
    ReadableRaftLog logMock = mock(ReadableRaftLog.class);
    when(logMock.appendIndex()).thenReturn(100L);
    when(state.commitIndex()).thenReturn(-1L);
    when(state.entryLog()).thenReturn(logMock);
    when(state.followerStates()).thenReturn(followerState);
    // both leader and follower are in the same term
    when(state.term()).thenReturn(4L);
    // when
    // that leader is asked to handle a response from that follower that says that the follower is up to date
    RaftMessages.AppendEntries.Response response = appendEntriesResponse().success().matchIndex(90).term(4).from(instance2).build();
    Outcome outcome = leader.handle(response, state, mock(Log.class));
    // then
    // The leader should not be trying to send any messages to that instance
    assertTrue(outcome.getOutgoingMessages().isEmpty());
    // And the follower state should be updated
    FollowerStates<MemberId> leadersViewOfFollowerStates = outcome.getFollowerStates();
    assertEquals(90, leadersViewOfFollowerStates.get(instance2).getMatchIndex());
}

Example 4 with ReadableRaftLog

use of org.neo4j.causalclustering.core.consensus.log.ReadableRaftLog in project neo4j by neo4j.

the class AppendingTest method shouldNotAllowTruncationAtCommit.

@Test
public void shouldNotAllowTruncationAtCommit() throws Exception {
    // given
    long commitIndex = 5;
    long localTermForAllEntries = 1L;
    Outcome outcome = mock(Outcome.class);
    ReadableRaftLog logMock = mock(ReadableRaftLog.class);
    // for simplicity, all entries are at term 1
    when(logMock.readEntryTerm(anyLong())).thenReturn(localTermForAllEntries);
    when(logMock.appendIndex()).thenReturn(commitIndex);
    ReadableRaftState state = mock(ReadableRaftState.class);
    when(state.entryLog()).thenReturn(logMock);
    when(state.commitIndex()).thenReturn(commitIndex);
    // when - then
    try {
        Appending.handleAppendEntriesRequest(state, outcome, new RaftMessages.AppendEntries.Request(aMember, localTermForAllEntries, commitIndex - 1, localTermForAllEntries, new RaftLogEntry[] { new RaftLogEntry(localTermForAllEntries + 1, ReplicatedInteger.valueOf(2)) }, commitIndex + 3), NullLog.getInstance());
        fail("Appending should not allow truncation at or before the commit index");
    } catch (IllegalStateException expected) {
    // ok
    }
}

Example 5 with ReadableRaftLog

use of org.neo4j.causalclustering.core.consensus.log.ReadableRaftLog in project neo4j by neo4j.

the class AppendingTest method shouldPerformTruncation.

@Test
public void shouldPerformTruncation() throws Exception {
    // when
    // we have a log appended up to appendIndex, and committed somewhere before that
    long appendIndex = 5;
    long localTermForAllEntries = 1L;
    Outcome outcome = mock(Outcome.class);
    ReadableRaftLog logMock = mock(ReadableRaftLog.class);
    // for simplicity, all entries are at term 1
    when(logMock.readEntryTerm(anyLong())).thenReturn(localTermForAllEntries);
    when(logMock.appendIndex()).thenReturn(appendIndex);
    ReadableRaftState state = mock(ReadableRaftState.class);
    when(state.entryLog()).thenReturn(logMock);
    when(state.commitIndex()).thenReturn(appendIndex - 3);
    // when
    // the leader asks to append after the commit index an entry that mismatches on term
    Appending.handleAppendEntriesRequest(state, outcome, new RaftMessages.AppendEntries.Request(aMember, localTermForAllEntries, appendIndex - 2, localTermForAllEntries, new RaftLogEntry[] { new RaftLogEntry(localTermForAllEntries + 1, ReplicatedInteger.valueOf(2)) }, appendIndex + 3), NullLog.getInstance());
    // then
    // we must produce a TruncateLogCommand at the earliest mismatching index
    verify(outcome, times(1)).addLogCommand(argThat(new LogCommandMatcher(appendIndex - 1)));
}