Examples with ZKWatcher org.apache.hadoop.hbase.zookeeper.ZKWatcher used on opensource projects

Example 36 with ZKWatcher

use of org.apache.hadoop.hbase.zookeeper.ZKWatcher in project hbase by apache.

the class TestMetaRegionLocationCache method testMetaRegionLocationCache.

/**
 * Tests MetaRegionLocationCache's init procedure to make sure that it correctly watches the base
 * znode for notifications.
 */
@Test
public void testMetaRegionLocationCache() throws Exception {
    final String parentZnodeName = "/randomznodename";
    Configuration conf = new Configuration(TEST_UTIL.getConfiguration());
    conf.set(HConstants.ZOOKEEPER_ZNODE_PARENT, parentZnodeName);
    ServerName sn = ServerName.valueOf("localhost", 1234, 5678);
    try (ZKWatcher zkWatcher = new ZKWatcher(conf, null, null, true)) {
        // A thread that repeatedly creates and drops an unrelated child znode. This is to simulate
        // some ZK activity in the background.
        MultithreadedTestUtil.TestContext ctx = new MultithreadedTestUtil.TestContext(conf);
        ctx.addThread(new MultithreadedTestUtil.RepeatingTestThread(ctx) {

            @Override
            public void doAnAction() throws Exception {
                final String testZnode = parentZnodeName + "/child";
                ZKUtil.createNodeIfNotExistsAndWatch(zkWatcher, testZnode, testZnode.getBytes());
                ZKUtil.deleteNode(zkWatcher, testZnode);
            }
        });
        ctx.startThreads();
        try {
            MetaRegionLocationCache metaCache = new MetaRegionLocationCache(zkWatcher);
            // meta znodes do not exist at this point, cache should be empty.
            assertTrue(metaCache.getMetaRegionLocations().isEmpty());
            // assignment.
            for (int i = 0; i < 3; i++) {
                // Updates the meta znodes.
                MetaTableLocator.setMetaLocation(zkWatcher, sn, i, RegionState.State.OPEN);
            }
            // Wait until the meta cache is populated.
            int iters = 0;
            while (iters++ < 10) {
                if (metaCache.getMetaRegionLocations().size() == 3) {
                    break;
                }
                Thread.sleep(1000);
            }
            List<HRegionLocation> metaLocations = metaCache.getMetaRegionLocations();
            assertEquals(3, metaLocations.size());
            for (HRegionLocation location : metaLocations) {
                assertEquals(sn, location.getServerName());
            }
        } finally {
            // clean up.
            ctx.stop();
            ZKUtil.deleteChildrenRecursively(zkWatcher, parentZnodeName);
        }
    }
}

Example 37 with ZKWatcher

use of org.apache.hadoop.hbase.zookeeper.ZKWatcher in project hbase by apache.

the class TestMetaWithReplicasBasic method testZookeeperNodesForReplicas.

@Test
public void testZookeeperNodesForReplicas() throws Exception {
    // Checks all the znodes exist when meta's replicas are enabled
    ZKWatcher zkw = TEST_UTIL.getZooKeeperWatcher();
    Configuration conf = TEST_UTIL.getConfiguration();
    String baseZNode = conf.get(HConstants.ZOOKEEPER_ZNODE_PARENT, HConstants.DEFAULT_ZOOKEEPER_ZNODE_PARENT);
    String primaryMetaZnode = ZNodePaths.joinZNode(baseZNode, conf.get("zookeeper.znode.metaserver", "meta-region-server"));
    // check that the data in the znode is parseable (this would also mean the znode exists)
    byte[] data = ZKUtil.getData(zkw, primaryMetaZnode);
    ProtobufUtil.toServerName(data);
    for (int i = 1; i < 3; i++) {
        String secZnode = ZNodePaths.joinZNode(baseZNode, conf.get("zookeeper.znode.metaserver", "meta-region-server") + "-" + i);
        String str = zkw.getZNodePaths().getZNodeForReplica(i);
        assertTrue(str.equals(secZnode));
        // check that the data in the znode is parseable (this would also mean the znode exists)
        data = ZKUtil.getData(zkw, secZnode);
        ProtobufUtil.toServerName(data);
    }
}

Example 38 with ZKWatcher

use of org.apache.hadoop.hbase.zookeeper.ZKWatcher in project hbase by apache.

the class TestMasterCoprocessorExceptionWithAbort method testExceptionFromCoprocessorWhenCreatingTable.

@Test
public void testExceptionFromCoprocessorWhenCreatingTable() throws IOException {
    SingleProcessHBaseCluster cluster = UTIL.getHBaseCluster();
    HMaster master = cluster.getMaster();
    MasterCoprocessorHost host = master.getMasterCoprocessorHost();
    BuggyMasterObserver cp = host.findCoprocessor(BuggyMasterObserver.class);
    assertFalse("No table created yet", cp.wasCreateTableCalled());
    // set a watch on the zookeeper /hbase/master node. If the master dies,
    // the node will be deleted.
    ZKWatcher zkw = new ZKWatcher(UTIL.getConfiguration(), "unittest", new Abortable() {

        @Override
        public void abort(String why, Throwable e) {
            throw new RuntimeException("Fatal ZK error: " + why, e);
        }

        @Override
        public boolean isAborted() {
            return false;
        }
    });
    MasterTracker masterTracker = new MasterTracker(zkw, "/hbase/master", new Abortable() {

        @Override
        public void abort(String why, Throwable e) {
            throw new RuntimeException("Fatal ZK master tracker error, why=", e);
        }

        @Override
        public boolean isAborted() {
            return false;
        }
    });
    masterTracker.start();
    zkw.registerListener(masterTracker);
    // Test (part of the) output that should have be printed by master when it aborts:
    // (namely the part that shows the set of loaded coprocessors).
    // In this test, there is only a single coprocessor (BuggyMasterObserver).
    assertTrue(HMaster.getLoadedCoprocessors().contains(TestMasterCoprocessorExceptionWithAbort.BuggyMasterObserver.class.getName()));
    CreateTableThread createTableThread = new CreateTableThread(UTIL);
    // Attempting to create a table (using createTableThread above) triggers an NPE in BuggyMasterObserver.
    // Master will then abort and the /hbase/master zk node will be deleted.
    createTableThread.start();
    // Wait up to 30 seconds for master's /hbase/master zk node to go away after master aborts.
    for (int i = 0; i < 30; i++) {
        if (masterTracker.masterZKNodeWasDeleted == true) {
            break;
        }
        try {
            Thread.sleep(1000);
        } catch (InterruptedException e) {
            fail("InterruptedException while waiting for master zk node to " + "be deleted.");
        }
    }
    assertTrue("Master aborted on coprocessor exception, as expected.", masterTracker.masterZKNodeWasDeleted);
    createTableThread.interrupt();
    try {
        createTableThread.join(1000);
    } catch (InterruptedException e) {
        assertTrue("Ignoring InterruptedException while waiting for " + " createTableThread.join().", true);
    }
}

Example 39 with ZKWatcher

use of org.apache.hadoop.hbase.zookeeper.ZKWatcher in project hbase by apache.

the class VerifyReplication method getPeerQuorumConfig.

private static Pair<ReplicationPeerConfig, Configuration> getPeerQuorumConfig(final Configuration conf, String peerId) throws IOException {
    ZKWatcher localZKW = null;
    try {
        localZKW = new ZKWatcher(conf, "VerifyReplication", new Abortable() {

            @Override
            public void abort(String why, Throwable e) {
            }

            @Override
            public boolean isAborted() {
                return false;
            }
        });
        ReplicationPeerStorage storage = ReplicationStorageFactory.getReplicationPeerStorage(localZKW, conf);
        ReplicationPeerConfig peerConfig = storage.getPeerConfig(peerId);
        return Pair.newPair(peerConfig, ReplicationUtils.getPeerClusterConfiguration(peerConfig, conf));
    } catch (ReplicationException e) {
        throw new IOException("An error occurred while trying to connect to the remote peer cluster", e);
    } finally {
        if (localZKW != null) {
            localZKW.close();
        }
    }
}

Example 40 with ZKWatcher

use of org.apache.hadoop.hbase.zookeeper.ZKWatcher in project hbase by apache.

the class ZNodeClearer method clear.

/**
 * Delete the master znode if its content (ServerName string) is the same
 *  as the one in the znode file. (env: HBASE_ZNODE_FILE). I case of master-rs
 *  colloaction we extract ServerName string from rsZnode path.(HBASE-14861)
 * @return true on successful deletion, false otherwise.
 */
public static boolean clear(Configuration conf) {
    Configuration tempConf = new Configuration(conf);
    tempConf.setInt("zookeeper.recovery.retry", 0);
    ZKWatcher zkw;
    try {
        zkw = new ZKWatcher(tempConf, "clean znode for master", new Abortable() {

            @Override
            public void abort(String why, Throwable e) {
            }

            @Override
            public boolean isAborted() {
                return false;
            }
        });
    } catch (IOException e) {
        LOG.warn("Can't connect to zookeeper to read the master znode", e);
        return false;
    }
    String znodeFileContent;
    try {
        znodeFileContent = ZNodeClearer.readMyEphemeralNodeOnDisk();
        return MasterAddressTracker.deleteIfEquals(zkw, znodeFileContent);
    } catch (FileNotFoundException fnfe) {
        // If no file, just keep going -- return success.
        LOG.warn("Can't find the znode file; presume non-fatal", fnfe);
        return true;
    } catch (IOException e) {
        LOG.warn("Can't read the content of the znode file", e);
        return false;
    } finally {
        zkw.close();
    }
}