/*
* Copyright (C) 2010-2101 Alibaba Group Holding Limited.
*
* Licensed 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.otter.shared.arbitrate.impl.setl.zookeeper;
import org.I0Itec.zkclient.exception.ZkException;
import org.I0Itec.zkclient.exception.ZkNoNodeException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.util.Assert;
import com.alibaba.otter.shared.arbitrate.exception.ArbitrateException;
import com.alibaba.otter.shared.arbitrate.impl.communication.ArbitrateCommmunicationClient;
import com.alibaba.otter.shared.arbitrate.impl.config.ArbitrateConfigUtils;
import com.alibaba.otter.shared.arbitrate.impl.manage.ChannelArbitrateEvent;
import com.alibaba.otter.shared.arbitrate.impl.setl.ArbitrateFactory;
import com.alibaba.otter.shared.arbitrate.impl.setl.TerminArbitrateEvent;
import com.alibaba.otter.shared.arbitrate.impl.setl.helper.StagePathUtils;
import com.alibaba.otter.shared.arbitrate.impl.setl.monitor.TerminMonitor;
import com.alibaba.otter.shared.arbitrate.impl.setl.zookeeper.termin.NormalTerminProcess;
import com.alibaba.otter.shared.arbitrate.impl.setl.zookeeper.termin.WarningTerminProcess;
import com.alibaba.otter.shared.arbitrate.impl.zookeeper.ZooKeeperClient;
import com.alibaba.otter.shared.arbitrate.model.TerminEventData;
import com.alibaba.otter.shared.arbitrate.model.TerminEventData.TerminType;
import com.alibaba.otter.shared.common.model.config.channel.Channel;
import com.alibaba.otter.shared.common.utils.JsonUtils;
import com.alibaba.otter.shared.common.utils.zookeeper.ZkClientx;
import com.alibaba.otter.shared.communication.model.arbitrate.StopChannelEvent;
/**
* 处理termin信号
*
* @author jianghang 2011-8-9 下午04:39:20
*/
public class TerminZooKeeperArbitrateEvent implements TerminArbitrateEvent {
private static final Logger logger = LoggerFactory.getLogger(TerminZooKeeperArbitrateEvent.class);
private ZkClientx zookeeper = ZooKeeperClient.getInstance();
private ArbitrateCommmunicationClient arbitrateCommmunicationClient;
private NormalTerminProcess normalTerminProcess;
private WarningTerminProcess warningTerminProcess;
private ChannelArbitrateEvent channelEvent;
/**
* <pre>
* 算法:
* 1. 开始阻塞获取符合条件的processId，获取对应的data数据直接返回
* </pre>
*/
public TerminEventData await(Long pipelineId) throws InterruptedException {
Assert.notNull(pipelineId);
TerminMonitor terminMonitor = ArbitrateFactory.getInstance(pipelineId, TerminMonitor.class);
Long processId = terminMonitor.waitForProcess(); // 符合条件的processId
if (logger.isDebugEnabled()) {
logger.debug("## await pipeline[{}] processId[{}] is termin", pipelineId, processId);
}
// 根据pipelineId+processId构造对应的path
String path = StagePathUtils.getTermin(pipelineId, processId);
try {
byte[] data = zookeeper.readData(path);
return JsonUtils.unmarshalFromByte(data, TerminEventData.class);
} catch (ZkNoNodeException e) {
logger.error("pipeline[{}] processId[{}] is process", pipelineId, processId);
terminMonitor.ack(processId); // modify for 2012-09-08, 发生主备切换时，await会进入死循环，针对NoNode后直接从内存队列中移除
return await(pipelineId); // 再取下一个节点
} catch (ZkException e) {
throw new ArbitrateException("Termin_await", e);
}
}
/**
* 消耗掉所有的termin信号
*/
public void exhaust(Long pipelineId) {
Assert.notNull(pipelineId);
TerminMonitor terminMonitor = ArbitrateFactory.getInstance(pipelineId, TerminMonitor.class);
int size = terminMonitor.size();
try {
for (int i = 0; i < size; i++) {
Long processId;
processId = terminMonitor.waitForProcess();
TerminEventData data = new TerminEventData();
data.setPipelineId(pipelineId);
data.setProcessId(processId);
ack(data);
}
} catch (InterruptedException e) {
throw new ArbitrateException(e);
}
}
/**
* <pre>
* 算法:
* 1. 客户端处理完成对应的termin事件后，反馈给仲裁器处理完成。仲裁器根据对应S.E.T.L的反馈情况，判断是否删除对应的termin信号
* </pre>
*/
public void ack(TerminEventData data) {
Assert.notNull(data);
// 目前只有select模块需要发送ack信号，这里一旦收到一个信号后就删除对应的termin节点，后续可扩展
// 删除termin节点
String path = StagePathUtils.getTermin(data.getPipelineId(), data.getProcessId());
try {
zookeeper.delete(path);
} catch (ZkNoNodeException e) {
// ignore,说明节点已经被删除
} catch (ZkException e) {
throw new ArbitrateException("Termin_ack", e);
}
TerminMonitor terminMonitor = ArbitrateFactory.getInstance(data.getPipelineId(), TerminMonitor.class);
terminMonitor.ack(data.getProcessId());
}
/**
* 查询当前待处理的termin信号的总数
*/
public int size(Long pipelineId) {
Assert.notNull(pipelineId);
TerminMonitor terminMonitor = ArbitrateFactory.getInstance(pipelineId, TerminMonitor.class);
return terminMonitor.size();
}
/**
* <pre>
* 算法:
* 1. 创建对应的termin节点,标志process为终结状态
* </pre>
*/
public void single(final TerminEventData data) {
// 正向处理
final TerminType type = data.getType();
if (type.isNormal()) {
Assert.notNull(data.getProcessId());
normalTerminProcess.process(data); // 单独处理
} else if (type.isWarning()) {
warningTerminProcess.process(data); // warn单独处理，不需要关闭相关的pipeline
} else {
Channel channel = ArbitrateConfigUtils.getChannel(data.getPipelineId());
if (data.getType().isRollback()) {
boolean paused = channelEvent.pause(channel.getId());
if (paused) {// 如果pause成功，则发送报警信息
warningTerminProcess.process(data);
}
} else if (data.getType().isShutdown()) {
boolean shutdowned = channelEvent.stop(channel.getId());
// 发送报警信息
if (shutdowned) {
warningTerminProcess.process(data);
}
// 发送关闭命令给manager
StopChannelEvent event = new StopChannelEvent();
event.setChannelId(channel.getId());
arbitrateCommmunicationClient.callManager(event);
} else if (data.getType().isRestart()) {
boolean restarted = channelEvent.restart(channel.getId());
// 发送报警信息
if (restarted) {
warningTerminProcess.process(data);
}
}
}
}
// ================== setter / getter ===================
public void setArbitrateCommmunicationClient(ArbitrateCommmunicationClient arbitrateCommmunicationClient) {
this.arbitrateCommmunicationClient = arbitrateCommmunicationClient;
}
public void setNormalTerminProcess(NormalTerminProcess normalTerminProcess) {
this.normalTerminProcess = normalTerminProcess;
}
public void setWarningTerminProcess(WarningTerminProcess warningTerminProcess) {
this.warningTerminProcess = warningTerminProcess;
}
public void setChannelEvent(ChannelArbitrateEvent channelEvent) {
this.channelEvent = channelEvent;
}
}