/**
* 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.tajo.rpc;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.EventLoopGroup;
import io.netty.util.internal.logging.CommonsLoggerFactory;
import io.netty.util.internal.logging.InternalLoggerFactory;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import javax.annotation.concurrent.ThreadSafe;
import java.net.ConnectException;
import java.net.InetSocketAddress;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.Properties;
@ThreadSafe
public class RpcClientManager {
private static final Log LOG = LogFactory.getLog(RpcClientManager.class);
/* entries will be removed by ConnectionCloseFutureListener */
private static final Map<RpcConnectionKey, NettyClientBase>
clients = Collections.synchronizedMap(new HashMap<RpcConnectionKey, NettyClientBase>());
private static RpcClientManager instance;
static {
InternalLoggerFactory.setDefaultFactory(new CommonsLoggerFactory());
instance = new RpcClientManager();
}
private RpcClientManager() {
}
public static RpcClientManager getInstance() {
return instance;
}
private <T extends NettyClientBase> T makeClient(RpcConnectionKey rpcConnectionKey,
Properties rpcParams)
throws NoSuchMethodException, ConnectException, ClassNotFoundException {
return makeClient(NettyUtils.getDefaultEventLoopGroup(), rpcConnectionKey, rpcParams);
}
private <T extends NettyClientBase> T makeClient(EventLoopGroup eventLoopGroup,
RpcConnectionKey rpcConnectionKey,
Properties rpcParams)
throws NoSuchMethodException, ClassNotFoundException, ConnectException {
NettyClientBase client;
if (rpcConnectionKey.asyncMode) {
client = new AsyncRpcClient(eventLoopGroup, rpcConnectionKey, rpcParams);
} else {
client = new BlockingRpcClient(eventLoopGroup, rpcConnectionKey, rpcParams);
}
return (T) client;
}
/**
* Connect a {@link NettyClientBase} to the remote {@link NettyServerBase}, and returns rpc client by protocol.
* This client will be shared per protocol and address. Client is removed in shared map when a client is closed
*/
public <T extends NettyClientBase> T getClient(InetSocketAddress addr,
Class<?> protocolClass,
boolean asyncMode,
Properties rpcParams)
throws NoSuchMethodException, ClassNotFoundException, ConnectException {
RpcConnectionKey key = new RpcConnectionKey(addr, protocolClass, asyncMode);
NettyClientBase client;
synchronized (clients) {
client = clients.get(key);
if (client == null) {
clients.put(key, client = makeClient(key, rpcParams));
}
}
if (!client.isConnected()) {
final NettyClientBase target = client;
client.subscribeEvent(target.getKey(), new ChannelEventListener() {
@Override
public void channelRegistered(ChannelHandlerContext ctx) {
/* Register client to managed map */
clients.put(target.getKey(), target);
ctx.channel().closeFuture().addListener(new ClientCloseFutureListener(target.getKey()));
}
@Override
public void channelUnregistered(ChannelHandlerContext ctx) {
// nothing to do
}
});
}
client.connect();
assert client.isConnected();
return (T) client;
}
/**
* Connect a {@link NettyClientBase} to the remote {@link NettyServerBase}, and returns rpc client by protocol.
* This client does not managed. It should close.
*/
public <T extends NettyClientBase> T newClient(InetSocketAddress addr,
Class<?> protocolClass,
boolean asyncMode,
Properties rpcParams)
throws NoSuchMethodException, ClassNotFoundException, ConnectException {
return newClient(new RpcConnectionKey(addr, protocolClass, asyncMode), rpcParams);
}
/**
*
* @param key RpcConnectionKey
* @param <T> Rpc Protocol Class
* @return Rpc Client Class
* @throws NoSuchMethodException
* @throws ClassNotFoundException
* @throws ConnectException
*/
public synchronized <T extends NettyClientBase> T newClient(RpcConnectionKey key,
Properties connectionParameters)
throws NoSuchMethodException, ClassNotFoundException, ConnectException {
T client = makeClient(key, connectionParameters);
client.connect();
assert client.isConnected();
return client;
}
public synchronized <T extends NettyClientBase> T newBlockingClient(InetSocketAddress addr,
Class<?> protocolClass,
EventLoopGroup eventLoopGroup,
Properties rpcParams)
throws NoSuchMethodException, ClassNotFoundException, ConnectException {
T client = makeClient(eventLoopGroup, new RpcConnectionKey(addr, protocolClass, false), rpcParams);
client.connect();
assert client.isConnected();
return client;
}
/**
* Request to close this clients
* After it is closed, it is removed from clients map.
*/
public static void close() {
LOG.info("Closing RPC client manager");
synchronized (clients) {
for (NettyClientBase eachClient : clients.values()) {
try {
eachClient.close();
} catch (Exception e) {
LOG.error(e.getMessage(), e);
}
}
}
}
/**
* Close client manager and shutdown Netty RPC worker pool
* After it is shutdown it is not possible to reuse it again.
*/
public static void shutdown() {
NettyUtils.shutdownGracefully();
}
protected static boolean contains(RpcConnectionKey key) {
return clients.containsKey(key);
}
public static void cleanup(NettyClientBase... clients) {
for (NettyClientBase client : clients) {
if (client != null) {
try {
client.close();
} catch (Exception e) {
if (LOG.isDebugEnabled()) {
LOG.debug("Exception in closing " + client.getKey(), e);
}
}
}
}
}
static class ClientCloseFutureListener implements ChannelFutureListener {
private RpcConnectionKey key;
public ClientCloseFutureListener(RpcConnectionKey key) {
this.key = key;
}
@Override
public void operationComplete(ChannelFuture future) throws Exception {
clients.remove(key);
}
}
}