/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.alibaba.wasp.master;
import com.alibaba.wasp.EntityGroupInfo;
import com.alibaba.wasp.ServerName;
import com.alibaba.wasp.zookeeper.ZooKeeperWatcher;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.zookeeper.AsyncCallback.StringCallback;
import org.apache.zookeeper.KeeperException;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.data.Stat;
import java.util.Map;
import java.util.concurrent.atomic.AtomicInteger;
/**
* Callback handler for creating unassigned offline znodes used during bulk
* assign, async setting entityGroup to offline.
*/
public class OfflineCallback implements StringCallback {
private final Log LOG = LogFactory.getLog(OfflineCallback.class);
private final ExistCallback callBack;
private final ZooKeeperWatcher zkw;
private final ServerName destination;
private final AtomicInteger counter;
OfflineCallback(final ZooKeeperWatcher zkw, final ServerName destination,
final AtomicInteger counter,
final Map<String, Integer> offlineNodesVersions) {
this.callBack = new ExistCallback(destination, counter,
offlineNodesVersions);
this.destination = destination;
this.counter = counter;
this.zkw = zkw;
}
@Override
public void processResult(int rc, String path, Object ctx, String name) {
if (rc == KeeperException.Code.NODEEXISTS.intValue()) {
LOG.warn("Node for " + path + " already exists");
} else if (rc != 0) {
// This is result code. If non-zero, need to resubmit.
LOG.warn("rc != 0 for " + path + " -- retryable connectionloss -- "
+ "FIX see http://wiki.apache.org/hadoop/ZooKeeper/FAQ#A2");
this.counter.addAndGet(1);
return;
}
if (LOG.isDebugEnabled()) {
LOG.debug("rs=" + ctx + ", server=" + destination);
}
// Async exists to set a watcher so we'll get triggered when
// unassigned node changes.
ZooKeeper zk = this.zkw.getRecoverableZooKeeper().getZooKeeper();
zk.exists(path, this.zkw, callBack, ctx);
}
/**
* Callback handler for the exists call that sets watcher on unassigned
* znodes. Used during bulk assign on startup.
*/
static class ExistCallback implements StatCallback {
private final Log LOG = LogFactory.getLog(ExistCallback.class);
private final Map<String, Integer> offlineNodesVersions;
private final AtomicInteger counter;
private ServerName destination;
ExistCallback(final ServerName destination, final AtomicInteger counter,
final Map<String, Integer> offlineNodesVersions) {
this.offlineNodesVersions = offlineNodesVersions;
this.destination = destination;
this.counter = counter;
}
@Override
public void processResult(int rc, String path, Object ctx, Stat stat) {
if (rc != 0) {
// This is result code. If non-zero, need to resubmit.
LOG.warn("rc != 0 for " + path + " -- retryable connectionloss -- "
+ "FIX see http://wiki.apache.org/hadoop/ZooKeeper/FAQ#A2");
this.counter.addAndGet(1);
return;
}
if (LOG.isDebugEnabled()) {
LOG.debug("rs=" + ctx + ", server=" + destination);
}
EntityGroupInfo entityGroup = ((EntityGroupState) ctx).getEntityGroup();
offlineNodesVersions.put(entityGroup.getEncodedName(),
Integer.valueOf(stat.getVersion()));
this.counter.addAndGet(1);
}
}
}