org.apache.dubbo.remoting.zookeeper.AbstractZookeeperTransporter Maven / Gradle / Ivy
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/*
* 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 org.apache.dubbo.remoting.zookeeper;
import org.apache.dubbo.common.URL;
import org.apache.dubbo.common.constants.RemotingConstants;
import org.apache.dubbo.common.logger.Logger;
import org.apache.dubbo.common.logger.LoggerFactory;
import org.apache.dubbo.common.utils.StringUtils;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import static org.apache.dubbo.common.constants.CommonConstants.TIMEOUT_KEY;
/**
* AbstractZookeeperTransporter is abstract implements of ZookeeperTransporter.
*
* If you want to extends this, implements createZookeeperClient.
*/
public abstract class AbstractZookeeperTransporter implements ZookeeperTransporter {
private static final Logger logger = LoggerFactory.getLogger(ZookeeperTransporter.class);
private final Map zookeeperClientMap = new ConcurrentHashMap<>();
/**
* share connect for registry, metadata, etc..
*
* Make sure the connection is connected.
*
* @param url
* @return
*/
@Override
public ZookeeperClient connect(URL url) {
ZookeeperClient zookeeperClient;
// address format: {[username:password@]address}
List addressList = getURLBackupAddress(url);
// The field define the zookeeper server , including protocol, host, port, username, password
if ((zookeeperClient = fetchAndUpdateZookeeperClientCache(addressList)) != null && zookeeperClient.isConnected()) {
logger.info("find valid zookeeper client from the cache for address: " + url);
return zookeeperClient;
}
// avoid creating too many connections， so add lock
synchronized (zookeeperClientMap) {
if ((zookeeperClient = fetchAndUpdateZookeeperClientCache(addressList)) != null && zookeeperClient.isConnected()) {
logger.info("find valid zookeeper client from the cache for address: " + url);
return zookeeperClient;
}
zookeeperClient = createZookeeperClient(url);
logger.info("No valid zookeeper client found from cache, therefore create a new client for url. " + url);
writeToClientMap(addressList, zookeeperClient);
}
return zookeeperClient;
}
/**
* @param url the url that will create zookeeper connection .
* The url in AbstractZookeeperTransporter#connect parameter is rewritten by this one.
* such as: zookeeper://127.0.0.1:2181/org.apache.dubbo.remoting.zookeeper.ZookeeperTransporter
* @return
*/
protected abstract ZookeeperClient createZookeeperClient(URL url);
/**
* get the ZookeeperClient from cache, the ZookeeperClient must be connected.
*
* It is not private method for unit test.
*
* @param addressList
* @return
*/
public ZookeeperClient fetchAndUpdateZookeeperClientCache(List addressList) {
ZookeeperClient zookeeperClient = null;
for (String address : addressList) {
if ((zookeeperClient = zookeeperClientMap.get(address)) != null && zookeeperClient.isConnected()) {
break;
}
}
if (zookeeperClient != null && zookeeperClient.isConnected()) {
writeToClientMap(addressList, zookeeperClient);
}
return zookeeperClient;
}
/**
* get all zookeeper urls (such as :zookeeper://127.0.0.1:2181?127.0.0.1:8989,127.0.0.1:9999)
*
* @param url such as:zookeeper://127.0.0.1:2181?127.0.0.1:8989,127.0.0.1:9999
* @return such as 127.0.0.1:2181,127.0.0.1:8989,127.0.0.1:9999
*/
public List getURLBackupAddress(URL url) {
List addressList = new ArrayList();
addressList.add(url.getAddress());
addressList.addAll(url.getParameter(RemotingConstants.BACKUP_KEY, Collections.EMPTY_LIST));
String authPrefix = null;
if (StringUtils.isNotEmpty(url.getUsername())) {
StringBuilder buf = new StringBuilder();
buf.append(url.getUsername());
if (StringUtils.isNotEmpty(url.getPassword())) {
buf.append(":");
buf.append(url.getPassword());
}
buf.append("@");
authPrefix = buf.toString();
}
if (StringUtils.isNotEmpty(authPrefix)) {
List authedAddressList = new ArrayList<>(addressList.size());
for (String addr : addressList) {
authedAddressList.add(authPrefix + addr);
}
return authedAddressList;
}
return addressList;
}
/**
* write address-ZookeeperClient relationship to Map
*
* @param addressList
* @param zookeeperClient
*/
void writeToClientMap(List addressList, ZookeeperClient zookeeperClient) {
for (String address : addressList) {
zookeeperClientMap.put(address, zookeeperClient);
}
}
/**
* redefine the url for zookeeper. just keep protocol, username, password, host, port, and individual parameter.
*
* @param url
* @return
*/
URL toClientURL(URL url) {
Map parameterMap = new HashMap<>();
// for CuratorZookeeperClient
if (url.getParameter(TIMEOUT_KEY) != null) {
parameterMap.put(TIMEOUT_KEY, url.getParameter(TIMEOUT_KEY));
}
if (url.getParameter(RemotingConstants.BACKUP_KEY) != null) {
parameterMap.put(RemotingConstants.BACKUP_KEY, url.getParameter(RemotingConstants.BACKUP_KEY));
}
return new URL(url.getProtocol(), url.getUsername(), url.getPassword(), url.getHost(), url.getPort(),
ZookeeperTransporter.class.getName(), parameterMap);
}
/**
* for unit test
*
* @return
*/
public Map getZookeeperClientMap() {
return zookeeperClientMap;
}
}