/*
* 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.activemq.transport.amqp.client.transport;
import java.io.IOException;
import java.net.URI;
import java.security.Principal;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicBoolean;
import org.apache.activemq.transport.amqp.client.util.IOExceptionSupport;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import io.netty.bootstrap.Bootstrap;
import io.netty.buffer.ByteBuf;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelOption;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.FixedRecvByteBufAllocator;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.logging.LoggingHandler;
import io.netty.handler.ssl.SslHandler;
import io.netty.util.concurrent.Future;
import io.netty.util.concurrent.GenericFutureListener;
/**
* TCP based transport that uses Netty as the underlying IO layer.
*/
public class NettyTcpTransport implements NettyTransport {
private static final Logger LOG = LoggerFactory.getLogger(NettyTcpTransport.class);
private static final int SHUTDOWN_TIMEOUT = 100;
protected Bootstrap bootstrap;
protected EventLoopGroup group;
protected Channel channel;
protected NettyTransportListener listener;
protected final NettyTransportOptions options;
protected final URI remote;
private final AtomicBoolean connected = new AtomicBoolean();
private final AtomicBoolean closed = new AtomicBoolean();
private final CountDownLatch connectLatch = new CountDownLatch(1);
private volatile IOException failureCause;
/**
* Create a new transport instance
*
* @param remoteLocation
* the URI that defines the remote resource to connect to.
* @param options
* the transport options used to configure the socket connection.
*/
public NettyTcpTransport(URI remoteLocation, NettyTransportOptions options) {
this(null, remoteLocation, options);
}
/**
* Create a new transport instance
*
* @param listener
* the TransportListener that will receive events from this Transport.
* @param remoteLocation
* the URI that defines the remote resource to connect to.
* @param options
* the transport options used to configure the socket connection.
*/
public NettyTcpTransport(NettyTransportListener listener, URI remoteLocation, NettyTransportOptions options) {
if (options == null) {
throw new IllegalArgumentException("Transport Options cannot be null");
}
if (remoteLocation == null) {
throw new IllegalArgumentException("Transport remote location cannot be null");
}
this.options = options;
this.listener = listener;
this.remote = remoteLocation;
}
@Override
public void connect() throws IOException {
if (listener == null) {
throw new IllegalStateException("A transport listener must be set before connection attempts.");
}
final SslHandler sslHandler;
if (isSSL()) {
try {
sslHandler = NettyTransportSupport.createSslHandler(getRemoteLocation(), getSslOptions());
} catch (Exception ex) {
// TODO: can we stop it throwing Exception?
throw IOExceptionSupport.create(ex);
}
} else {
sslHandler = null;
}
group = new NioEventLoopGroup(1);
bootstrap = new Bootstrap();
bootstrap.group(group);
bootstrap.channel(NioSocketChannel.class);
bootstrap.handler(new ChannelInitializer<Channel>() {
@Override
public void initChannel(Channel connectedChannel) throws Exception {
configureChannel(connectedChannel, sslHandler);
}
});
configureNetty(bootstrap, getTransportOptions());
ChannelFuture future = bootstrap.connect(getRemoteHost(), getRemotePort());
future.addListener(new ChannelFutureListener() {
@Override
public void operationComplete(ChannelFuture future) throws Exception {
if (!future.isSuccess()) {
handleException(future.channel(), IOExceptionSupport.create(future.cause()));
}
}
});
try {
connectLatch.await();
} catch (InterruptedException ex) {
LOG.debug("Transport connection was interrupted.");
Thread.interrupted();
failureCause = IOExceptionSupport.create(ex);
}
if (failureCause != null) {
// Close out any Netty resources now as they are no longer needed.
if (channel != null) {
channel.close().syncUninterruptibly();
channel = null;
}
if (group != null) {
Future<?> fut = group.shutdownGracefully(0, SHUTDOWN_TIMEOUT, TimeUnit.MILLISECONDS);
if (!fut.awaitUninterruptibly(2 * SHUTDOWN_TIMEOUT)) {
LOG.trace("Channel group shutdown failed to complete in allotted time");
}
group = null;
}
throw failureCause;
} else {
// Connected, allow any held async error to fire now and close the transport.
channel.eventLoop().execute(new Runnable() {
@Override
public void run() {
if (failureCause != null) {
channel.pipeline().fireExceptionCaught(failureCause);
}
}
});
}
}
@Override
public boolean isConnected() {
return connected.get();
}
@Override
public boolean isSSL() {
return options.isSSL();
}
@Override
public void close() throws IOException {
if (closed.compareAndSet(false, true)) {
connected.set(false);
try {
if (channel != null) {
channel.close().syncUninterruptibly();
}
} finally {
if (group != null) {
Future<?> fut = group.shutdownGracefully(0, SHUTDOWN_TIMEOUT, TimeUnit.MILLISECONDS);
if (!fut.awaitUninterruptibly(2 * SHUTDOWN_TIMEOUT)) {
LOG.trace("Channel group shutdown failed to complete in allotted time");
}
}
}
}
}
@Override
public ByteBuf allocateSendBuffer(int size) throws IOException {
checkConnected();
return channel.alloc().ioBuffer(size, size);
}
@Override
public void send(ByteBuf output) throws IOException {
checkConnected();
int length = output.readableBytes();
if (length == 0) {
return;
}
LOG.trace("Attempted write of: {} bytes", length);
channel.writeAndFlush(output);
}
@Override
public NettyTransportListener getTransportListener() {
return listener;
}
@Override
public void setTransportListener(NettyTransportListener listener) {
this.listener = listener;
}
@Override
public NettyTransportOptions getTransportOptions() {
return options;
}
@Override
public URI getRemoteLocation() {
return remote;
}
@Override
public Principal getLocalPrincipal() {
Principal result = null;
if (isSSL()) {
SslHandler sslHandler = channel.pipeline().get(SslHandler.class);
result = sslHandler.engine().getSession().getLocalPrincipal();
}
return result;
}
// ----- Internal implementation details, can be overridden as needed -----//
protected String getRemoteHost() {
return remote.getHost();
}
protected int getRemotePort() {
if (remote.getPort() != -1) {
return remote.getPort();
} else {
return isSSL() ? getSslOptions().getDefaultSslPort() : getTransportOptions().getDefaultTcpPort();
}
}
protected void addAdditionalHandlers(ChannelPipeline pipeline) {
}
protected ChannelInboundHandlerAdapter createChannelHandler() {
return new NettyTcpTransportHandler();
}
// ----- Event Handlers which can be overridden in subclasses -------------//
protected void handleConnected(Channel channel) throws Exception {
LOG.trace("Channel has become active! Channel is {}", channel);
connectionEstablished(channel);
}
protected void handleChannelInactive(Channel channel) throws Exception {
LOG.trace("Channel has gone inactive! Channel is {}", channel);
if (connected.compareAndSet(true, false) && !closed.get()) {
LOG.trace("Firing onTransportClosed listener");
listener.onTransportClosed();
}
}
protected void handleException(Channel channel, Throwable cause) throws Exception {
LOG.trace("Exception on channel! Channel is {}", channel);
if (connected.compareAndSet(true, false) && !closed.get()) {
LOG.trace("Firing onTransportError listener");
if (failureCause != null) {
listener.onTransportError(failureCause);
} else {
listener.onTransportError(cause);
}
} else {
// Hold the first failure for later dispatch if connect succeeds.
// This will then trigger disconnect using the first error reported.
if (failureCause == null) {
LOG.trace("Holding error until connect succeeds: {}", cause.getMessage());
failureCause = IOExceptionSupport.create(cause);
}
connectionFailed(channel, failureCause);
}
}
// ----- State change handlers and checks ---------------------------------//
protected final void checkConnected() throws IOException {
if (!connected.get()) {
throw new IOException("Cannot send to a non-connected transport.");
}
}
/*
* Called when the transport has successfully connected and is ready for use.
*/
private void connectionEstablished(Channel connectedChannel) {
channel = connectedChannel;
connected.set(true);
connectLatch.countDown();
}
/*
* Called when the transport connection failed and an error should be returned.
*/
private void connectionFailed(Channel failedChannel, IOException cause) {
failureCause = cause;
channel = failedChannel;
connected.set(false);
connectLatch.countDown();
}
private NettyTransportSslOptions getSslOptions() {
return (NettyTransportSslOptions) getTransportOptions();
}
private void configureNetty(Bootstrap bootstrap, NettyTransportOptions options) {
bootstrap.option(ChannelOption.TCP_NODELAY, options.isTcpNoDelay());
bootstrap.option(ChannelOption.CONNECT_TIMEOUT_MILLIS, options.getConnectTimeout());
bootstrap.option(ChannelOption.SO_KEEPALIVE, options.isTcpKeepAlive());
bootstrap.option(ChannelOption.SO_LINGER, options.getSoLinger());
if (options.getSendBufferSize() != -1) {
bootstrap.option(ChannelOption.SO_SNDBUF, options.getSendBufferSize());
}
if (options.getReceiveBufferSize() != -1) {
bootstrap.option(ChannelOption.SO_RCVBUF, options.getReceiveBufferSize());
bootstrap.option(ChannelOption.RCVBUF_ALLOCATOR, new FixedRecvByteBufAllocator(options.getReceiveBufferSize()));
}
if (options.getTrafficClass() != -1) {
bootstrap.option(ChannelOption.IP_TOS, options.getTrafficClass());
}
}
private void configureChannel(final Channel channel, final SslHandler sslHandler) throws Exception {
if (isSSL()) {
channel.pipeline().addLast(sslHandler);
}
if (getTransportOptions().isTraceBytes()) {
channel.pipeline().addLast("logger", new LoggingHandler(getClass()));
}
addAdditionalHandlers(channel.pipeline());
channel.pipeline().addLast(createChannelHandler());
}
// ----- Handle connection events -----------------------------------------//
protected abstract class NettyDefaultHandler<E> extends SimpleChannelInboundHandler<E> {
@Override
public void channelRegistered(ChannelHandlerContext context) throws Exception {
channel = context.channel();
}
@Override
public void channelActive(ChannelHandlerContext context) throws Exception {
// In the Secure case we need to let the handshake complete before we
// trigger the connected event.
if (!isSSL()) {
handleConnected(context.channel());
} else {
SslHandler sslHandler = context.pipeline().get(SslHandler.class);
sslHandler.handshakeFuture().addListener(new GenericFutureListener<Future<Channel>>() {
@Override
public void operationComplete(Future<Channel> future) throws Exception {
if (future.isSuccess()) {
LOG.trace("SSL Handshake has completed: {}", channel);
handleConnected(channel);
} else {
LOG.trace("SSL Handshake has failed: {}", channel);
handleException(channel, future.cause());
}
}
});
}
}
@Override
public void channelInactive(ChannelHandlerContext context) throws Exception {
handleChannelInactive(context.channel());
}
@Override
public void exceptionCaught(ChannelHandlerContext context, Throwable cause) throws Exception {
handleException(context.channel(), cause);
}
}
// ----- Handle Binary data from connection -------------------------------//
protected class NettyTcpTransportHandler extends NettyDefaultHandler<ByteBuf> {
@Override
protected void channelRead0(ChannelHandlerContext ctx, ByteBuf buffer) throws Exception {
LOG.trace("New data read: {} bytes incoming: {}", buffer.readableBytes(), buffer);
listener.onData(buffer);
}
}
}