org.apache.zookeeper.common.NettyUtils 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.zookeeper.common;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.epoll.Epoll;
import io.netty.channel.epoll.EpollEventLoopGroup;
import io.netty.channel.epoll.EpollServerSocketChannel;
import io.netty.channel.epoll.EpollSocketChannel;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.ServerSocketChannel;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;
import java.net.InetAddress;
import java.net.NetworkInterface;
import java.net.SocketException;
import java.util.Collections;
import java.util.Enumeration;
import java.util.HashSet;
import java.util.Set;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Helper methods for netty code.
*/
public class NettyUtils {
private static final Logger LOG = LoggerFactory.getLogger(NettyUtils.class);
private static final int DEFAULT_INET_ADDRESS_COUNT = 1;
/**
* If {@link Epoll#isAvailable()} == true, returns a new
* {@link EpollEventLoopGroup}, otherwise returns a new
* {@link NioEventLoopGroup}. Creates the event loop group using the
* default number of threads.
* @return a new {@link EventLoopGroup}.
*/
public static EventLoopGroup newNioOrEpollEventLoopGroup() {
if (Epoll.isAvailable()) {
return new EpollEventLoopGroup();
} else {
return new NioEventLoopGroup();
}
}
/**
* If {@link Epoll#isAvailable()} == true, returns a new
* {@link EpollEventLoopGroup}, otherwise returns a new
* {@link NioEventLoopGroup}. Creates the event loop group using the
* specified number of threads instead of the default.
* @param nThreads see {@link NioEventLoopGroup#NioEventLoopGroup(int)}.
* @return a new {@link EventLoopGroup}.
*/
public static EventLoopGroup newNioOrEpollEventLoopGroup(int nThreads) {
if (Epoll.isAvailable()) {
return new EpollEventLoopGroup(nThreads);
} else {
return new NioEventLoopGroup(nThreads);
}
}
/**
* If {@link Epoll#isAvailable()} == true, returns
* {@link EpollSocketChannel}, otherwise returns {@link NioSocketChannel}.
* @return a socket channel class.
*/
public static Class nioOrEpollSocketChannel() {
if (Epoll.isAvailable()) {
return EpollSocketChannel.class;
} else {
return NioSocketChannel.class;
}
}
/**
* If {@link Epoll#isAvailable()} == true, returns
* {@link EpollServerSocketChannel}, otherwise returns
* {@link NioServerSocketChannel}.
* @return a server socket channel class.
*/
public static Class nioOrEpollServerSocketChannel() {
if (Epoll.isAvailable()) {
return EpollServerSocketChannel.class;
} else {
return NioServerSocketChannel.class;
}
}
/**
* Attempts to detect and return the number of local network addresses that could be
* used by a client to reach this server. This means we exclude the following address types:
*
* - Multicast addresses. Zookeeper server sockets use TCP, thus cannot bind to a multicast address.
* - Link-local addresses. Routers don't forward traffic sent to a link-local address, so
* any realistic server deployment would not have clients using these.
* - Loopback addresses. These are typically only used for testing.
*
* Any remaining addresses are counted, and the total count is returned. This number is
* used to configure the number of threads for the "boss" event loop group, to make sure we have
* enough threads for each address in case the server is configured to listen on
* all available addresses.
* If listing the network interfaces fails, this method will return 1.
*
* @return the number of client-reachable local network addresses found, or
* 1 if listing the network interfaces fails.
*/
public static int getClientReachableLocalInetAddressCount() {
try {
Set validInetAddresses = new HashSet<>();
Enumeration allNetworkInterfaces = NetworkInterface.getNetworkInterfaces();
for (NetworkInterface networkInterface : Collections.list(allNetworkInterfaces)) {
for (InetAddress inetAddress : Collections.list(networkInterface.getInetAddresses())) {
if (inetAddress.isLinkLocalAddress()) {
LOG.debug("Ignoring link-local InetAddress {}", inetAddress);
continue;
}
if (inetAddress.isMulticastAddress()) {
LOG.debug("Ignoring multicast InetAddress {}", inetAddress);
continue;
}
if (inetAddress.isLoopbackAddress()) {
LOG.debug("Ignoring loopback InetAddress {}", inetAddress);
continue;
}
validInetAddresses.add(inetAddress);
}
}
LOG.debug("Detected {} local network addresses: {}", validInetAddresses.size(), validInetAddresses);
return validInetAddresses.size() > 0 ? validInetAddresses.size() : DEFAULT_INET_ADDRESS_COUNT;
} catch (SocketException ex) {
LOG.warn("Failed to list all network interfaces, assuming 1", ex);
return DEFAULT_INET_ADDRESS_COUNT;
}
}
}