/**
* 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.zookeeper.admin;
import java.io.IOException;
import java.util.List;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.ZooDefs;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.KeeperException;
import org.apache.zookeeper.AsyncCallback.DataCallback;
import org.apache.zookeeper.client.ZKClientConfig;
import org.apache.zookeeper.common.StringUtils;
import org.apache.zookeeper.data.Stat;
import org.apache.zookeeper.proto.GetDataResponse;
import org.apache.zookeeper.proto.ReconfigRequest;
import org.apache.zookeeper.proto.ReplyHeader;
import org.apache.zookeeper.proto.RequestHeader;
import org.apache.zookeeper.server.DataTree;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* This is the main class for ZooKeeperAdmin client library.
* This library is used to perform cluster administration tasks,
* such as reconfigure cluster membership. The ZooKeeperAdmin class
* inherits ZooKeeper and has similar usage pattern as ZooKeeper class.
* Please check {@link ZooKeeper} class document for more details.
*
* @since 3.5.3
*/
// See ZooKeeper.java for an explanation of why we need @SuppressWarnings("try")
@SuppressWarnings("try")
public class ZooKeeperAdmin extends ZooKeeper {
private static final Logger LOG = LoggerFactory.getLogger(ZooKeeperAdmin.class);
/**
* Create a ZooKeeperAdmin object which is used to perform dynamic reconfiguration
* operations.
*
* @param connectString
* comma separated host:port pairs, each corresponding to a zk
* server. e.g. "127.0.0.1:3000,127.0.0.1:3001,127.0.0.1:3002" If
* the optional chroot suffix is used the example would look
* like: "127.0.0.1:3000,127.0.0.1:3001,127.0.0.1:3002/app/a"
* where the client would be rooted at "/app/a" and all paths
* would be relative to this root - ie getting/setting/etc...
* "/foo/bar" would result in operations being run on
* "/app/a/foo/bar" (from the server perspective).
* @param sessionTimeout
* session timeout in milliseconds
* @param watcher
* a watcher object which will be notified of state changes, may
* also be notified for node events
*
* @throws IOException
* in cases of network failure
* @throws IllegalArgumentException
* if an invalid chroot path is specified
*
* @see ZooKeeper#ZooKeeper(String, int, Watcher)
*
*/
public ZooKeeperAdmin(String connectString, int sessionTimeout, Watcher watcher)
throws IOException {
super(connectString, sessionTimeout, watcher);
}
/**
* Create a ZooKeeperAdmin object which is used to perform dynamic reconfiguration
* operations.
*
* @param connectString
* comma separated host:port pairs, each corresponding to a zk
* server. e.g. "127.0.0.1:3000,127.0.0.1:3001,127.0.0.1:3002" If
* the optional chroot suffix is used the example would look
* like: "127.0.0.1:3000,127.0.0.1:3001,127.0.0.1:3002/app/a"
* where the client would be rooted at "/app/a" and all paths
* would be relative to this root - ie getting/setting/etc...
* "/foo/bar" would result in operations being run on
* "/app/a/foo/bar" (from the server perspective).
* @param sessionTimeout
* session timeout in milliseconds
* @param watcher
* a watcher object which will be notified of state changes, may
* also be notified for node events
* @param conf
* passing this conf object gives each client the flexibility of
* configuring properties differently compared to other instances
*
* @throws IOException
* in cases of network failure
* @throws IllegalArgumentException
* if an invalid chroot path is specified
*
* @see ZooKeeper#ZooKeeper(String, int, Watcher, ZKClientConfig)
*/
public ZooKeeperAdmin(String connectString, int sessionTimeout, Watcher watcher,
ZKClientConfig conf) throws IOException {
super(connectString, sessionTimeout, watcher, conf);
}
/**
* Create a ZooKeeperAdmin object which is used to perform dynamic reconfiguration
* operations.
*
* @param connectString
* comma separated host:port pairs, each corresponding to a zk
* server. e.g. "127.0.0.1:3000,127.0.0.1:3001,127.0.0.1:3002" If
* the optional chroot suffix is used the example would look
* like: "127.0.0.1:3000,127.0.0.1:3001,127.0.0.1:3002/app/a"
* where the client would be rooted at "/app/a" and all paths
* would be relative to this root - ie getting/setting/etc...
* "/foo/bar" would result in operations being run on
* "/app/a/foo/bar" (from the server perspective).
* @param sessionTimeout
* session timeout in milliseconds
* @param watcher
* a watcher object which will be notified of state changes, may
* also be notified for node events
* @param canBeReadOnly
* whether the created client is allowed to go to
* read-only mode in case of partitioning. Read-only mode
* basically means that if the client can't find any majority
* servers but there's partitioned server it could reach, it
* connects to one in read-only mode, i.e. read requests are
* allowed while write requests are not. It continues seeking for
* majority in the background.
*
* @throws IOException
* in cases of network failure
* @throws IllegalArgumentException
* if an invalid chroot path is specified
*
* @see ZooKeeper#ZooKeeper(String, int, Watcher, boolean)
*/
public ZooKeeperAdmin(String connectString, int sessionTimeout, Watcher watcher,
boolean canBeReadOnly) throws IOException {
super(connectString, sessionTimeout, watcher, canBeReadOnly);
}
/**
* Reconfigure - add/remove servers. Return the new configuration.
* @param joiningServers
* a comma separated list of servers being added (incremental reconfiguration)
* @param leavingServers
* a comma separated list of servers being removed (incremental reconfiguration)
* @param newMembers
* a comma separated list of new membership (non-incremental reconfiguration)
* @param fromConfig
* version of the current configuration
* (optional - causes reconfiguration to throw an exception if configuration is no longer current)
* @param stat the stat of /zookeeper/config znode will be copied to this
* parameter if not null.
* @return new configuration
* @throws InterruptedException If the server transaction is interrupted.
* @throws KeeperException If the server signals an error with a non-zero error code.
*/
public byte[] reconfigure(String joiningServers, String leavingServers,
String newMembers, long fromConfig, Stat stat) throws KeeperException, InterruptedException {
RequestHeader h = new RequestHeader();
h.setType(ZooDefs.OpCode.reconfig);
ReconfigRequest request = new ReconfigRequest(joiningServers, leavingServers, newMembers, fromConfig);
GetDataResponse response = new GetDataResponse();
ReplyHeader r = cnxn.submitRequest(h, request, response, null);
if (r.getErr() != 0) {
throw KeeperException.create(KeeperException.Code.get(r.getErr()), "");
}
if (stat != null) {
DataTree.copyStat(response.getStat(), stat);
}
return response.getData();
}
/**
* Convenience wrapper around reconfig that takes Lists of strings instead of comma-separated servers.
*
* @see #reconfigure
*
*/
public byte[] reconfigure(List<String> joiningServers, List<String> leavingServers,
List<String> newMembers, long fromConfig,
Stat stat) throws KeeperException, InterruptedException {
return reconfigure(StringUtils.joinStrings(joiningServers, ","),
StringUtils.joinStrings(leavingServers, ","),
StringUtils.joinStrings(newMembers, ","),
fromConfig, stat);
}
/**
* The Asynchronous version of reconfig.
*
* @see #reconfigure
*
**/
public void reconfigure(String joiningServers, String leavingServers,
String newMembers, long fromConfig, DataCallback cb, Object ctx) {
RequestHeader h = new RequestHeader();
h.setType(ZooDefs.OpCode.reconfig);
ReconfigRequest request = new ReconfigRequest(joiningServers, leavingServers, newMembers, fromConfig);
GetDataResponse response = new GetDataResponse();
cnxn.queuePacket(h, new ReplyHeader(), request, response, cb,
ZooDefs.CONFIG_NODE, ZooDefs.CONFIG_NODE, ctx, null);
}
/**
* Convenience wrapper around asynchronous reconfig that takes Lists of strings instead of comma-separated servers.
*
* @see #reconfigure
*
*/
public void reconfigure(List<String> joiningServers,
List<String> leavingServers, List<String> newMembers, long fromConfig,
DataCallback cb, Object ctx) {
reconfigure(StringUtils.joinStrings(joiningServers, ","),
StringUtils.joinStrings(leavingServers, ","),
StringUtils.joinStrings(newMembers, ","),
fromConfig, cb, ctx);
}
/**
* String representation of this ZooKeeperAdmin client. Suitable for things
* like logging.
*
* Do NOT count on the format of this string, it may change without
* warning.
*
* @since 3.5.3
*/
@Override
public String toString() {
return super.toString();
}
}