Examples with TO_SLAVE org.neo4j.kernel.ha.cluster.HighAvailabilityMemberState.TO_SLAVE used on opensource projects

Example 1 with TO_SLAVE

use of org.neo4j.kernel.ha.cluster.HighAvailabilityMemberState.TO_SLAVE in project neo4j by neo4j.

the class HighAvailabilityModeSwitcherTest method shouldRecognizeNewMasterIfNewMasterBecameAvailableDuringSwitch.

@Test
public void shouldRecognizeNewMasterIfNewMasterBecameAvailableDuringSwitch() throws Throwable {
    // When messages coming in the following ordering, the slave should detect that the master id has changed
    // M1: Get masterIsAvailable for instance 1 at PENDING state, changing PENDING -> TO_SLAVE
    // M2: Get masterIsAvailable for instance 2 at TO_SLAVE state, changing TO_SLAVE -> TO_SLAVE
    // Given
    final CountDownLatch firstMasterAvailableHandled = new CountDownLatch(1);
    final CountDownLatch secondMasterAvailableComes = new CountDownLatch(1);
    final CountDownLatch secondMasterAvailableHandled = new CountDownLatch(1);
    SwitchToSlaveCopyThenBranch switchToSlave = mock(SwitchToSlaveCopyThenBranch.class);
    HighAvailabilityModeSwitcher modeSwitcher = new HighAvailabilityModeSwitcher(switchToSlave, mock(SwitchToMaster.class), mock(Election.class), mock(ClusterMemberAvailability.class), mock(ClusterClient.class), mock(Supplier.class), new InstanceId(4), new ComponentSwitcherContainer(), neoStoreDataSourceSupplierMock(), NullLogService.getInstance()) {

        @Override
        ScheduledExecutorService createExecutor() {
            final ScheduledExecutorService executor = mock(ScheduledExecutorService.class);
            final ExecutorService realExecutor = Executors.newSingleThreadExecutor();
            when(executor.submit(any(Runnable.class))).thenAnswer((Answer<Future<?>>) invocation -> realExecutor.submit((Runnable) () -> ((Runnable) invocation.getArguments()[0]).run()));
            when(executor.schedule(any(Runnable.class), anyLong(), any(TimeUnit.class))).thenAnswer((Answer<Future<?>>) invocation -> {
                realExecutor.submit((Callable<Void>) () -> {
                    firstMasterAvailableHandled.countDown();
                    secondMasterAvailableComes.await();
                    ((Runnable) invocation.getArguments()[0]).run();
                    secondMasterAvailableHandled.countDown();
                    return null;
                });
                return mock(ScheduledFuture.class);
            });
            return executor;
        }
    };
    modeSwitcher.init();
    modeSwitcher.start();
    modeSwitcher.listeningAt(URI.create("ha://server3?serverId=3"));
    // When
    // masterIsAvailable for instance 1
    URI uri1 = URI.create("ha://server1");
    // The first masterIsAvailable should fail so that the slave instance stops at TO_SLAVE state
    doThrow(new ComException("Fail to switch to slave and reschedule to retry")).when(switchToSlave).switchToSlave(any(LifeSupport.class), any(URI.class), eq(uri1), any(CancellationRequest.class));
    modeSwitcher.masterIsAvailable(new HighAvailabilityMemberChangeEvent(PENDING, TO_SLAVE, new InstanceId(1), uri1));
    // wait until the first masterIsAvailable triggers the exception handling
    firstMasterAvailableHandled.await();
    verify(switchToSlave).switchToSlave(any(LifeSupport.class), any(URI.class), eq(uri1), any(CancellationRequest.class));
    // masterIsAvailable for instance 2
    URI uri2 = URI.create("ha://server2");
    modeSwitcher.masterIsAvailable(new HighAvailabilityMemberChangeEvent(TO_SLAVE, TO_SLAVE, new InstanceId(2), uri2));
    secondMasterAvailableComes.countDown();
    // wait until switchToSlave method is invoked again
    secondMasterAvailableHandled.await();
    // Then
    // switchToSlave should be retried with new master id
    verify(switchToSlave).switchToSlave(any(LifeSupport.class), any(URI.class), eq(uri2), any(CancellationRequest.class));
}

Example 2 with TO_SLAVE

use of org.neo4j.kernel.ha.cluster.HighAvailabilityMemberState.TO_SLAVE in project neo4j by neo4j.

the class HighAvailabilityModeSwitcherTest method shouldNotResetAvailableMasterURIIfElectionResultReceived.

@Test
public void shouldNotResetAvailableMasterURIIfElectionResultReceived() throws Throwable {
    /*
         * It is possible that a masterIsElected nulls out the current available master URI in the HAMS. That can
         * be a problem if handing the mIE event is concurrent with an ongoing switch which re-runs because
         * the store was incompatible or a log was missing. In such a case it will find a null master URI on
         * rerun and it will fail.
         */
    // Given
    SwitchToSlaveCopyThenBranch switchToSlave = mock(SwitchToSlaveCopyThenBranch.class);
    // The fist run through switchToSlave
    final CountDownLatch firstCallMade = new CountDownLatch(1);
    // The second run through switchToSlave
    final CountDownLatch secondCallMade = new CountDownLatch(1);
    // The latch for waiting for the masterIsElected to come through
    final CountDownLatch waitForSecondMessage = new CountDownLatch(1);
    HighAvailabilityModeSwitcher toTest = new HighAvailabilityModeSwitcher(switchToSlave, mock(SwitchToMaster.class), mock(Election.class), mock(ClusterMemberAvailability.class), mock(ClusterClient.class), storeSupplierMock(), new InstanceId(1), new ComponentSwitcherContainer(), neoStoreDataSourceSupplierMock(), NullLogService.getInstance());
    URI uri1 = URI.create("ha://server1");
    toTest.init();
    toTest.start();
    toTest.listeningAt(URI.create("ha://server3?serverId=3"));
    when(switchToSlave.switchToSlave(any(LifeSupport.class), any(URI.class), any(URI.class), any(CancellationRequest.class))).thenAnswer(invocation -> {
        firstCallMade.countDown();
        waitForSecondMessage.await();
        throw new MismatchingStoreIdException(StoreId.DEFAULT, StoreId.DEFAULT);
    }).thenAnswer(invocation -> {
        secondCallMade.countDown();
        return URI.create("ha://server3");
    });
    // When
    // The first message goes through, start the first run
    toTest.masterIsAvailable(new HighAvailabilityMemberChangeEvent(PENDING, TO_SLAVE, new InstanceId(1), uri1));
    // Wait for it to be processed but get just before the exception
    firstCallMade.await();
    // It is just about to throw the exception, i.e. rerun. Send in the event
    toTest.masterIsElected(new HighAvailabilityMemberChangeEvent(TO_SLAVE, TO_SLAVE, new InstanceId(1), null));
    // Allow to continue and do the second run
    waitForSecondMessage.countDown();
    // Wait for the call to finish
    secondCallMade.await();
    // Then
    verify(switchToSlave, times(2)).switchToSlave(any(LifeSupport.class), any(URI.class), eq(uri1), any(CancellationRequest.class));
}