/*
* Copyright 2014 Matthias Einwag
*
* The jawampa authors license 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 ws.wamp.jawampa.transport.netty;
import java.net.SocketAddress;
import java.net.URI;
import java.util.List;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.ThreadFactory;
import javax.net.ssl.SSLException;
import ws.wamp.jawampa.ApplicationError;
import ws.wamp.jawampa.WampMessages.WampMessage;
import ws.wamp.jawampa.connection.IPendingWampConnection;
import ws.wamp.jawampa.connection.IPendingWampConnectionListener;
import ws.wamp.jawampa.connection.IWampClientConnectionConfig;
import ws.wamp.jawampa.connection.IWampConnection;
import ws.wamp.jawampa.connection.IWampConnectionListener;
import ws.wamp.jawampa.connection.IWampConnectionPromise;
import ws.wamp.jawampa.connection.IWampConnector;
import ws.wamp.jawampa.connection.IWampConnectorProvider;
import ws.wamp.jawampa.WampSerialization;
import io.netty.bootstrap.Bootstrap;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandler;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.codec.http.DefaultHttpHeaders;
import io.netty.handler.codec.http.HttpClientCodec;
import io.netty.handler.codec.http.HttpObjectAggregator;
import io.netty.handler.codec.http.websocketx.WebSocketClientHandshaker;
import io.netty.handler.codec.http.websocketx.WebSocketClientHandshakerFactory;
import io.netty.handler.codec.http.websocketx.WebSocketClientProtocolHandler;
import io.netty.handler.codec.http.websocketx.WebSocketFrameAggregator;
import io.netty.handler.codec.http.websocketx.WebSocketVersion;
import io.netty.handler.proxy.Socks5ProxyHandler;
import io.netty.handler.ssl.SslContext;
import io.netty.handler.ssl.util.InsecureTrustManagerFactory;
import io.netty.resolver.NoopAddressResolverGroup;
/**
* Returns factory methods for the establishment of WAMP connections between
* clients and routers.<br>
*/
public class NettyWampClientConnectorProvider implements IWampConnectorProvider {
@Override
public ScheduledExecutorService createScheduler() {
NioEventLoopGroup scheduler = new NioEventLoopGroup(1, new ThreadFactory() {
@Override
public Thread newThread(Runnable r) {
Thread t = new Thread(r, "WampClientEventLoop");
t.setDaemon(true);
return t;
}
});
return scheduler;
}
@Override
public IWampConnector createConnector(final URI uri,
IWampClientConnectionConfig configuration,
List<WampSerialization> serializations,
final SocketAddress proxyAddress) throws Exception {
String scheme = uri.getScheme();
scheme = scheme != null ? scheme : "";
// Check if the configuration is a netty configuration.
// However null is an allowed value
final NettyWampConnectionConfig nettyConfig;
if (configuration instanceof NettyWampConnectionConfig) {
nettyConfig = (NettyWampConnectionConfig) configuration;
} else if (configuration != null) {
throw new ApplicationError(ApplicationError.INVALID_CONNECTION_CONFIGURATION);
} else {
nettyConfig = null;
}
if (scheme.equalsIgnoreCase("ws") || scheme.equalsIgnoreCase("wss")) {
// Check the host and port field for validity
if (uri.getHost() == null || uri.getPort() == 0) {
throw new ApplicationError(ApplicationError.INVALID_URI);
}
// Initialize SSL when required
final boolean needSsl = uri.getScheme().equalsIgnoreCase("wss");
final SslContext sslCtx0;
if (needSsl && (nettyConfig == null || nettyConfig.sslContext() == null)) {
// Create a default SslContext when we got none provided through the constructor
try {
sslCtx0 = SslContext.newClientContext(InsecureTrustManagerFactory.INSTANCE);
}
catch (SSLException e) {
throw e;
}
} else if (needSsl) {
sslCtx0 = nettyConfig.sslContext();
} else {
sslCtx0 = null;
}
final String subProtocols = WampSerialization.makeWebsocketSubprotocolList(serializations);
final int maxFramePayloadLength = (nettyConfig == null )? NettyWampConnectionConfig.DEFAULT_MAX_FRAME_PAYLOAD_LENGTH : nettyConfig.getMaxFramePayloadLength();
// Return a factory that creates a channel for websocket connections
return new IWampConnector() {
@Override
public IPendingWampConnection connect(final ScheduledExecutorService scheduler,
final IPendingWampConnectionListener connectListener,
final IWampConnectionListener connectionListener) {
// Use well-known ports if not explicitly specified
final int port;
if (uri.getPort() == -1) {
if (needSsl) port = 443;
else port = 80;
} else port = uri.getPort();
final WebSocketClientHandshaker handshaker = WebSocketClientHandshakerFactory.newHandshaker(
uri, WebSocketVersion.V13, subProtocols,
false, new DefaultHttpHeaders(), maxFramePayloadLength);
/**
* Netty handler for that receives and processes WampMessages and state
* events from the pipeline.
* A new instance of this is created for each connection attempt.
*/
final ChannelHandler connectionHandler = new SimpleChannelInboundHandler<WampMessage>() {
boolean connectionWasEstablished = false;
/** Guard to prevent forwarding events aftert the channel was closed */
boolean wasClosed = false;
@Override
public void channelInactive(ChannelHandlerContext ctx) throws Exception {
if (wasClosed) return;
wasClosed = true;
if (connectionWasEstablished) {
connectionListener.transportClosed();
} else {
// The transport closed before the websocket handshake was completed
connectListener.connectFailed(new ApplicationError(ApplicationError.TRANSPORT_CLOSED));
}
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
if (wasClosed) return;
wasClosed = true;
if (connectionWasEstablished) {
connectionListener.transportError(cause);
} else {
// The transport closed before the websocket handshake was completed
connectListener.connectFailed(cause);
}
super.exceptionCaught(ctx, cause);
}
@Override
public void userEventTriggered(final ChannelHandlerContext ctx, Object evt) throws Exception {
if (wasClosed) return;
if (evt instanceof ConnectionEstablishedEvent) {
ConnectionEstablishedEvent ev = (ConnectionEstablishedEvent)evt;
final WampSerialization serialization = ev.serialization();
IWampConnection connection = new IWampConnection() {
@Override
public WampSerialization serialization() {
return serialization;
}
@Override
public boolean isSingleWriteOnly() {
return false;
}
@Override
public void sendMessage(WampMessage message, final IWampConnectionPromise<Void> promise) {
ChannelFuture f = ctx.writeAndFlush(message);
f.addListener(new ChannelFutureListener() {
@Override
public void operationComplete(ChannelFuture future) throws Exception {
if (future.isSuccess() || future.isCancelled())
promise.fulfill(null);
else
promise.reject(future.cause());
}
});
}
@Override
public void close(boolean sendRemaining, final IWampConnectionPromise<Void> promise) {
// sendRemaining is ignored. Remaining data is always sent
ctx.writeAndFlush(Unpooled.EMPTY_BUFFER)
.addListener(new ChannelFutureListener() {
@Override
public void operationComplete(ChannelFuture future) throws Exception {
future.channel()
.close()
.addListener(new ChannelFutureListener() {
@Override
public void operationComplete(ChannelFuture future) throws Exception {
if (future.isSuccess() || future.isCancelled())
promise.fulfill(null);
else
promise.reject(future.cause());
}
});
}
});
}
};
connectionWasEstablished = true;
// Connection to the remote host was established
// However the WAMP session is not established until the handshake was finished
connectListener.connectSucceeded(connection);
}
}
@Override
protected void channelRead0(ChannelHandlerContext ctx, WampMessage msg) throws Exception {
if (wasClosed) return;
assert (connectionWasEstablished);
connectionListener.messageReceived(msg);
}
};
// If the assigned scheduler is a netty eventloop use this
final EventLoopGroup nettyEventLoop;
if (scheduler instanceof EventLoopGroup) {
nettyEventLoop = (EventLoopGroup)scheduler;
} else {
connectListener.connectFailed(new ApplicationError(ApplicationError.INCOMATIBLE_SCHEDULER));
return IPendingWampConnection.Dummy;
}
Bootstrap b = new Bootstrap();
// things should be resolved on via the socks5 proxy
if (proxyAddress != null)
b.resolver(NoopAddressResolverGroup.INSTANCE);
b.group(nettyEventLoop)
.channel(NioSocketChannel.class)
.handler(new ChannelInitializer<SocketChannel>() {
@Override
protected void initChannel(SocketChannel ch) {
ChannelPipeline p = ch.pipeline();
if (proxyAddress != null) {
p.addFirst("proxy", new Socks5ProxyHandler(proxyAddress));
}
if (sslCtx0 != null) {
p.addLast(sslCtx0.newHandler(ch.alloc(),
uri.getHost(),
port));
}
p.addLast(
new HttpClientCodec(),
new HttpObjectAggregator(8192),
new WebSocketClientProtocolHandler(handshaker, false),
new WebSocketFrameAggregator(WampHandlerConfiguration.MAX_WEBSOCKET_FRAME_SIZE),
new WampClientWebsocketHandler(handshaker),
connectionHandler);
}
});
final ChannelFuture connectFuture = b.connect(uri.getHost(), port);
connectFuture.addListener(new ChannelFutureListener() {
@Override
public void operationComplete(ChannelFuture future) throws Exception {
if (future.isSuccess()) {
// Do nothing. The connection is only successful when the websocket handshake succeeds
} else {
// Remark: Might be called directly in addListener
// Therefore addListener should be the last call
// Remark2: This branch will be taken upon cancellation.
// This is required by the contract.
connectListener.connectFailed(future.cause());
}
}
});
// Return the connection in progress with the ability for cancellation
return new IPendingWampConnection() {
@Override
public void cancelConnect() {
connectFuture.cancel(false);
}
};
}
};
}
throw new ApplicationError(ApplicationError.INVALID_URI);
}
}