Examples with HighlyAvailableGraphDatabase org.neo4j.kernel.ha.HighlyAvailableGraphDatabase used on opensource projects

Example 6 with HighlyAvailableGraphDatabase

use of org.neo4j.kernel.ha.HighlyAvailableGraphDatabase in project neo4j by neo4j.

the class TransactionConstraintsIT method writeOperationOnSlaveHasToBePerformedWithinTransaction.

@Test
public void writeOperationOnSlaveHasToBePerformedWithinTransaction() throws Exception {
    // GIVEN
    HighlyAvailableGraphDatabase aSlave = cluster.getAnySlave();
    // WHEN
    try {
        aSlave.createNode();
        fail("Shouldn't be able to do a write operation outside a transaction");
    } catch (NotInTransactionException e) {
    // THEN
    }
}

Example 7 with HighlyAvailableGraphDatabase

use of org.neo4j.kernel.ha.HighlyAvailableGraphDatabase in project neo4j by neo4j.

the class TransactionConstraintsIT method deadlockDetectionInvolvingTwoSlaves.

@Test
public void deadlockDetectionInvolvingTwoSlaves() throws Exception {
    HighlyAvailableGraphDatabase slave1 = cluster.getAnySlave();
    deadlockDetectionBetween(slave1, cluster.getAnySlave(slave1));
}

Example 8 with HighlyAvailableGraphDatabase

use of org.neo4j.kernel.ha.HighlyAvailableGraphDatabase in project neo4j by neo4j.

the class TransactionConstraintsIT method writeOperationOnMasterHasToBePerformedWithinTransaction.

@Test
public void writeOperationOnMasterHasToBePerformedWithinTransaction() throws Exception {
    // GIVEN
    HighlyAvailableGraphDatabase master = cluster.getMaster();
    // WHEN
    try {
        master.createNode();
        fail("Shouldn't be able to do a write operation outside a transaction");
    } catch (NotInTransactionException e) {
    // THEN
    }
}

Example 9 with HighlyAvailableGraphDatabase

use of org.neo4j.kernel.ha.HighlyAvailableGraphDatabase in project neo4j by neo4j.

the class TransactionConstraintsIT method deadlockDetectionBetween.

private void deadlockDetectionBetween(HighlyAvailableGraphDatabase slave1, final HighlyAvailableGraphDatabase slave2) throws Exception {
    // GIVEN
    // -- two members acquiring a read lock on the same entity
    final Node commonNode;
    try (Transaction tx = slave1.beginTx()) {
        commonNode = slave1.createNode();
        tx.success();
    }
    OtherThreadExecutor<HighlyAvailableGraphDatabase> thread2 = new OtherThreadExecutor<>("T2", slave2);
    Transaction tx1 = slave1.beginTx();
    Transaction tx2 = thread2.execute(new BeginTx());
    tx1.acquireReadLock(commonNode);
    thread2.execute(state -> tx2.acquireReadLock(commonNode));
    // -- and one of them wanting (and awaiting) to upgrade its read lock to a write lock
    Future<Lock> writeLockFuture = thread2.executeDontWait(state -> {
        try (Transaction ignored = tx2) {
            return tx2.acquireWriteLock(commonNode);
        }
    });
    for (int i = 0; i < 10; i++) {
        thread2.waitUntilThreadState(Thread.State.TIMED_WAITING, Thread.State.WAITING);
        Thread.sleep(2);
    }
    try (// Close transaction no matter what happens
    Transaction ignored = tx1) {
        // WHEN
        tx1.acquireWriteLock(commonNode);
        // -- Deadlock detection is non-deterministic, so either the slave or the master will detect it
        writeLockFuture.get();
        fail("Deadlock exception should have been thrown");
    } catch (DeadlockDetectedException e) {
    // THEN -- deadlock should be avoided with this exception
    } catch (ExecutionException e) {
        // OR -- the tx2 thread fails with executionexception, caused by deadlock on its end
        assertThat(e.getCause(), instanceOf(DeadlockDetectedException.class));
    }
    thread2.close();
}

Example 10 with HighlyAvailableGraphDatabase

use of org.neo4j.kernel.ha.HighlyAvailableGraphDatabase in project neo4j by neo4j.

the class TransactionConstraintsIT method startTxAsSlaveAndFinishItAfterHavingSwitchedToMasterShouldNotSucceed.

@Test
public void startTxAsSlaveAndFinishItAfterHavingSwitchedToMasterShouldNotSucceed() throws Exception {
    // GIVEN
    GraphDatabaseService db = cluster.getAnySlave(getSlaveOnlySlave());
    // WHEN
    Transaction tx = db.beginTx();
    try {
        db.createNode().setProperty("name", "slave");
        tx.success();
    } finally {
        HighlyAvailableGraphDatabase oldMaster = cluster.getMaster();
        cluster.shutdown(oldMaster);
        // Wait for new master
        cluster.await(masterAvailable(oldMaster));
        assertFinishGetsTransactionFailure(tx);
    }
    // THEN
    assertEquals(db, cluster.getMaster());
    // to prevent a deadlock scenario which occurs if this test exists (and @After starts)
    // before the db has recovered from its KERNEL_PANIC
    awaitFullyOperational(db);
}