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

Example 11 with RaftLog

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

the class FollowerTest method shouldUpdateCommitIndexIfNecessary.

@Test
public void shouldUpdateCommitIndexIfNecessary() throws Exception {
    //  If leaderCommit > commitIndex, set commitIndex = min( leaderCommit, index of last new entry )
    // given
    RaftLog entryLog = new InMemoryRaftLog();
    entryLog.append(new RaftLogEntry(0, new RaftTestGroup(0)));
    RaftState state = raftState().myself(myself).entryLog(entryLog).build();
    Follower follower = new Follower();
    int localAppendIndex = 3;
    int localCommitIndex = localAppendIndex - 1;
    int term = 0;
    // append index is 0 based
    appendSomeEntriesToLog(state, follower, localAppendIndex, term, 1);
    // the next when-then simply verifies that the test is setup properly, with commit and append index as expected
    // when
    Outcome raftTestMemberOutcome = new Outcome(FOLLOWER, state);
    raftTestMemberOutcome.setCommitIndex(localCommitIndex);
    state.update(raftTestMemberOutcome);
    // then
    assertEquals(localAppendIndex, state.entryLog().appendIndex());
    assertEquals(localCommitIndex, state.commitIndex());
    // when
    // an append req comes in with leader commit index > localAppendIndex but localCommitIndex < localAppendIndex
    Outcome outcome = follower.handle(appendEntriesRequest().leaderTerm(term).prevLogIndex(3).prevLogTerm(term).leaderCommit(localCommitIndex + 4).build(), state, log());
    state.update(outcome);
    // then
    // The local commit index must be brought as far along as possible
    assertEquals(3, state.commitIndex());
}