/**
* 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.hedwig.server.netty;
import java.io.IOException;
import java.util.Map;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.channel.ChannelFuture;
import org.jboss.netty.channel.ChannelFutureListener;
import org.jboss.netty.channel.ChannelHandlerContext;
import org.jboss.netty.channel.ChannelPipelineCoverage;
import org.jboss.netty.channel.ChannelStateEvent;
import org.jboss.netty.channel.ExceptionEvent;
import org.jboss.netty.channel.MessageEvent;
import org.jboss.netty.channel.SimpleChannelHandler;
import org.jboss.netty.channel.group.ChannelGroup;
import org.jboss.netty.handler.codec.frame.CorruptedFrameException;
import org.jboss.netty.handler.codec.frame.TooLongFrameException;
import org.jboss.netty.handler.ssl.SslHandler;
import org.apache.hedwig.exceptions.PubSubException.MalformedRequestException;
import org.apache.hedwig.protocol.PubSubProtocol;
import org.apache.hedwig.protocol.PubSubProtocol.OperationType;
import org.apache.hedwig.protocol.PubSubProtocol.PubSubResponse;
import org.apache.hedwig.protoextensions.PubSubResponseUtils;
import org.apache.hedwig.server.handlers.ChannelDisconnectListener;
import org.apache.hedwig.server.handlers.Handler;
@ChannelPipelineCoverage("all")
public class UmbrellaHandler extends SimpleChannelHandler {
static Logger logger = LoggerFactory.getLogger(UmbrellaHandler.class);
private Map<OperationType, Handler> handlers;
private ChannelGroup allChannels;
private ChannelDisconnectListener subscribeHandler;
private boolean isSSLEnabled = false;
public UmbrellaHandler(ChannelGroup allChannels, Map<OperationType, Handler> handlers,
boolean isSSLEnabled) {
this.allChannels = allChannels;
this.isSSLEnabled = isSSLEnabled;
this.handlers = handlers;
subscribeHandler = (ChannelDisconnectListener) handlers.get(OperationType.SUBSCRIBE);
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e) throws Exception {
Throwable throwable = e.getCause();
// Add here if there are more exceptions we need to be able to tolerate.
// 1. IOException may be thrown when a channel is forcefully closed by
// the other end, or by the ProtobufDecoder when an invalid protobuf is
// received
// 2. TooLongFrameException is thrown by the LengthBasedDecoder if it
// receives a packet that is too big
// 3. CorruptedFramException is thrown by the LengthBasedDecoder when
// the length is negative etc.
if (throwable instanceof IOException || throwable instanceof TooLongFrameException
|| throwable instanceof CorruptedFrameException) {
e.getChannel().close();
if (logger.isDebugEnabled()) {
logger.debug("Uncaught exception", throwable);
}
} else {
// call our uncaught exception handler, which might decide to
// shutdown the system
Thread thread = Thread.currentThread();
thread.getUncaughtExceptionHandler().uncaughtException(thread, throwable);
}
}
@Override
public void channelOpen(ChannelHandlerContext ctx, ChannelStateEvent e) throws Exception {
// If SSL is NOT enabled, then we can add this channel to the
// ChannelGroup. Otherwise, that is done when the channel is connected
// and the SSL handshake has completed successfully.
if (!isSSLEnabled) {
allChannels.add(ctx.getChannel());
}
}
@Override
public void channelConnected(ChannelHandlerContext ctx, ChannelStateEvent e) throws Exception {
if (isSSLEnabled) {
ctx.getPipeline().get(SslHandler.class).handshake(e.getChannel()).addListener(new ChannelFutureListener() {
public void operationComplete(ChannelFuture future) throws Exception {
if (future.isSuccess()) {
if (logger.isDebugEnabled()) {
logger.debug("SSL handshake has completed successfully!");
}
allChannels.add(future.getChannel());
} else {
future.getChannel().close();
}
}
});
}
}
@Override
public void channelDisconnected(ChannelHandlerContext ctx, ChannelStateEvent e) throws Exception {
Channel channel = ctx.getChannel();
// subscribe handler needs to know about channel disconnects
subscribeHandler.channelDisconnected(channel);
channel.close();
}
public static void sendErrorResponseToMalformedRequest(Channel channel, long txnId, String msg) {
if (logger.isDebugEnabled()) {
logger.debug("Malformed request from " + channel.getRemoteAddress() + " msg, = " + msg);
}
MalformedRequestException mre = new MalformedRequestException(msg);
PubSubResponse response = PubSubResponseUtils.getResponseForException(mre, txnId);
channel.write(response);
}
@Override
public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) throws Exception {
if (!(e.getMessage() instanceof PubSubProtocol.PubSubRequest)) {
ctx.sendUpstream(e);
return;
}
PubSubProtocol.PubSubRequest request = (PubSubProtocol.PubSubRequest) e.getMessage();
Handler handler = handlers.get(request.getType());
Channel channel = ctx.getChannel();
long txnId = request.getTxnId();
if (handler == null) {
sendErrorResponseToMalformedRequest(channel, txnId, "Request type " + request.getType().getNumber()
+ " unknown");
return;
}
handler.handleRequest(request, channel);
}
}