cloud.tianai.rpc.registry.zookeeper.ZookeeperRegistry Maven / Gradle / Ivy
package cloud.tianai.rpc.registry.zookeeper;
import cloud.tianai.rpc.common.Result;
import cloud.tianai.rpc.common.URL;
import cloud.tianai.rpc.common.util.CollectionUtils;
import cloud.tianai.rpc.registory.api.AbstractRegistry;
import cloud.tianai.rpc.registory.api.NotifyListener;
import cloud.tianai.rpc.registory.api.StatusListener;
import lombok.extern.slf4j.Slf4j;
import org.I0Itec.zkclient.IZkChildListener;
import org.I0Itec.zkclient.IZkStateListener;
import org.I0Itec.zkclient.ZkClient;
import org.I0Itec.zkclient.exception.ZkNoNodeException;
import org.I0Itec.zkclient.exception.ZkNodeExistsException;
import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.Watcher;
import java.util.*;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.CopyOnWriteArraySet;
/**
* @Author: 天爱有情
* @Date: 2020/01/23 12:08
* @Description: 基于zookeeper的注册器
*/
@Slf4j
public class ZookeeperRegistry extends AbstractRegistry {
public static final String PROTOCOL = "zookeeper";
/**
* 默认的根目录地址.
*/
private final static String DEFAULT_ROOT = "/tianai-rpc";
private final static String PATH_SEPARATOR = "/";
/**
* 存放自定义监听器和 zk监听器的绑定
* NotifyListener -> IZkDataListener
*/
private Map notifyListenerZkDataListenerMap = new HashMap<>(32);
/**
* zk集群时使用，暂时不用.
*/
public static final String GROUP_KEY = "group";
/**
* zookeeper客户端.
*/
private ZkClient zkClient;
/**
* 根目录.
*/
private String root;
private Map registryCache = new ConcurrentHashMap<>(16);
@Override
protected void doShutdown() {
if (zkClient != null) {
zkClient.close();
}
notifyListenerZkDataListenerMap.clear();
}
@Override
protected void doStart(URL url) {
try {
init();
} catch (Exception e) {
// 启动设置为false
throw e;
}
}
@Override
protected void innerRegister(URL url) {
try {
try {
String path = getPath(url);
create(path + PATH_SEPARATOR + URL.encode(url.toString()));
} catch (Exception e) {
throw new IllegalStateException(e.getMessage(), e);
}
} catch (ZkNoNodeException e) {
// 创建
throw new IllegalStateException(e.getMessage(), e);
}
}
@Override
protected void doSubscribe(StatusListener statusListener) {
}
private void init() {
// todo zookeeperRegistry 这是暂时先设置为单机版
String address = getRegistryUrl().getAddress();
int timeout = Integer.parseInt(getRegistryUrl().getParameter("timeout", String.valueOf(5000)));
zkClient = new ZkClient(address, timeout);
zkClient.subscribeStateChanges(new WatcherListener(getStatusListenerSet()));
this.root = getRegistryUrl().getParameter(GROUP_KEY, DEFAULT_ROOT);
// 判断根节点是否存在，如果不存在则创建， 创建类型必须是持久类型的
createNodeIfNecessary(this.root, CreateMode.PERSISTENT);
//todo 启动一个守护线程定时清除为空的持久数据
}
private void createNodeIfNecessary(String node, CreateMode createMode) {
if (zkClient.exists(node)) {
return;
}
zkClient.create(node, null, createMode);
}
private String getPath(URL url) {
return toRootPath() + PATH_SEPARATOR + url.getServiceInterface();
}
@Override
public Result> lookup(URL url) {
List urls = Collections.emptyList();
try {
List children = zkClient.getChildren(getPath(url));
if (CollectionUtils.isNotEmpty(children)) {
urls = new ArrayList<>(children.size());
for (String child : children) {
String decodeChild = URL.decode(child);
URL u = URL.valueOf(decodeChild);
urls.add(u);
}
}
return Result.ofSuccess(urls);
} catch (Exception e) {
e.printStackTrace();
return Result.ofError(e.getMessage());
}
}
@Override
public String getProtocol() {
return PROTOCOL;
}
@Override
public void subscribe(URL url, NotifyListener listener) {
String path = getPath(url);
// 判断是否存在
if (!zkClient.exists(path)) {
// 如果不存在，创建一个空的node
create(path + PATH_SEPARATOR + URL.encode(url.toString()));
}
ZkChildListenerAdapter zkChildListenerAdapter = new ZkChildListenerAdapter(listener);
zkClient.subscribeChildChanges(path, zkChildListenerAdapter);
notifyListenerZkDataListenerMap.put(listener, zkChildListenerAdapter);
}
@Override
public void unsubscribe(URL url, NotifyListener listener) {
IZkChildListener iZkChildListener = notifyListenerZkDataListenerMap.get(listener);
if (!Objects.isNull(iZkChildListener)) {
// 如果不为空，则删除该监听器
zkClient.unsubscribeChildChanges(getPath(url), iZkChildListener);
}
}
public void destroy() {
if (zkClient != null) {
try {
zkClient.close();
zkClient = null;
} catch (Exception e) {
log.error("the service zk close faild info={}", getRegistryUrl());
}
}
}
private String toRootPath() {
return root;
}
public void create(String path) {
int indexOf = path.lastIndexOf(PATH_SEPARATOR);
if (indexOf > 0) {
// 父节点必须创建持久类型的数据
createPersistent(path.substring(0, indexOf));
}
// 创建临时节点
createEphemeral(path);
}
private void createEphemeral(String path) {
try {
zkClient.createEphemeral(path);
} catch (ZkNodeExistsException e) {
// 如果node存在， 删除，重新创建
deleteNode(path);
createEphemeral(path);
}
}
private void deleteNode(String path) {
zkClient.delete(path);
}
private void createPersistent(String path) {
int i = path.lastIndexOf('/');
if (i > 0) {
createPersistent(path.substring(0, i));
}
if (!zkClient.exists(path)) {
try {
zkClient.createPersistent(path);
} catch (ZkNodeExistsException e) {
// 如果node已存在，不做任何处理
log.warn("ZNode " + path + " already exists.", e);
}
}
}
private class WatcherListener implements IZkStateListener {
private Set statusListenerSet;
public WatcherListener(Set statusListenerSet) {
this.statusListenerSet = statusListenerSet;
}
@Override
public void handleStateChanged(Watcher.Event.KeeperState state) {
log.info("handleStateChanged() ===> {}", state);
if (Watcher.Event.KeeperState.Expired == state || Watcher.Event.KeeperState.Disconnected == state) {
log.info("重连zookeeper ===> ");
reConnected();
}
}
@Override
public void handleNewSession() {
if (log.isInfoEnabled()) {
log.info("zookeeper new session ========-------->, 重新注册, addressCache=", ZookeeperRegistry.this.registryCache);
} else {
System.out.println("new session------------==============================>, addressCache=" + ZookeeperRegistry.this.registryCache);
}
// 重新注册
ZookeeperRegistry.this.reRegister();
}
@Override
public void handleSessionEstablishmentError(Throwable error) {
// 回话建立错误
log.warn("zookkper回话建立错误， e=", error);
reConnected();
}
private void reConnected() {
try {
System.out.println("执行reConnect");
ZookeeperRegistry.this.destroy();
try {
//wait for the zk server start success!
Thread.sleep(2000);
} catch (InterruptedException e) {
log.error(e.getMessage(), e);
}
ZookeeperRegistry.this.init();
} catch (Exception e) {
// 报错后重新连接
e.printStackTrace();
reConnected();
return;
}
// 重新注册
ZookeeperRegistry.this.reRegister();
for (StatusListener statusListener : statusListenerSet) {
statusListener.reConnected();
}
}
}
public static class ZkChildListenerAdapter implements IZkChildListener {
private NotifyListener notifyListener;
public ZkChildListenerAdapter(NotifyListener notifyListener) {
this.notifyListener = notifyListener;
}
@Override
public void handleChildChange(String parentPath, List currentChilds) {
if (CollectionUtils.isEmpty(currentChilds)) {
notifyListener.notify(Collections.emptyList());
} else {
List urls = new ArrayList<>(currentChilds.size());
for (String child : currentChilds) {
String urlDecode = URL.decode(child);
urls.add(URL.valueOf(urlDecode));
}
notifyListener.notify(urls);
}
}
}
}