/*
* JBoss, Home of Professional Open Source.
* Copyright 2011, Red Hat, Inc., and individual contributors
* as indicated by the @author tags. See the copyright.txt file in the
* distribution for a full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.as.protocol.mgmt;
import java.io.DataInput;
import java.io.DataInputStream;
import java.io.IOException;
import java.io.OutputStream;
import org.jboss.as.protocol.StreamUtils;
import org.jboss.as.protocol.logging.ProtocolLogger;
import org.jboss.remoting3.Channel;
import org.jboss.remoting3.MessageInputStream;
import org.jboss.remoting3.MessageOutputStream;
/**
* Base receiver class for the management protocol support.
*
* @author Emanuel Muckenhuber
*/
public final class ManagementChannelReceiver implements Channel.Receiver {
/**
* Create a {@code ManagementChannelReceiver} which delegates protocol messages to
* a {@code ManagementMessageHandler}.
*
* @param handler the handler
* @return the receiver
*/
public static ManagementChannelReceiver createDelegating(final ManagementMessageHandler handler) {
assert handler != null;
return new ManagementChannelReceiver(handler);
}
private final ManagementMessageHandler handler;
private volatile long lastMessageTime;
private ManagementChannelReceiver(final ManagementMessageHandler handler) {
this.handler = handler;
}
@Override
public void handleMessage(final Channel channel, final MessageInputStream message) {
try {
ProtocolLogger.ROOT_LOGGER.tracef("%s handling incoming data", this);
lastMessageTime = System.currentTimeMillis();
final DataInput input = new DataInputStream(message);
final ManagementProtocolHeader header = ManagementProtocolHeader.parse(input);
final byte type = header.getType();
try {
if (type == ManagementProtocol.TYPE_PING) {
// Handle legacy ping/pong directly
ProtocolLogger.ROOT_LOGGER.tracef("Received ping on %s", this);
handlePing(channel, header);
} else if (type == ManagementProtocol.TYPE_PONG) {
// Nothing to do here
ProtocolLogger.ROOT_LOGGER.tracef("Received pong on %s", this);
} else if (type == ManagementProtocol.TYPE_BYE_BYE) {
// This signal has been a no-op for years and years, maybe since AS 7.0.0.Final!
// JBoss Remoting deals with channel close itself; we don't do it at the
// management protocol level
ProtocolLogger.ROOT_LOGGER.tracef("Received bye bye on %s, ignoring", this);
} else {
// Handle a message
handler.handleMessage(channel, input, header);
}
} finally {
try {
//noinspection StatementWithEmptyBody
while (message.read() != -1) {
// drain the message to workaround a potential remoting buffer leak
}
} catch (IOException ignore) {
//
}
}
message.close();
} catch(IOException e) {
handleError(channel, e);
} catch (Exception e) {
handleError(channel, new IOException(e));
} finally {
StreamUtils.safeClose(message);
ProtocolLogger.ROOT_LOGGER.tracef("%s done handling incoming data", this);
}
channel.receiveMessage(this);
}
/**
* @return the time of the most recent invocation of {@link #handleMessage(Channel, MessageInputStream)}
*/
public long getLastMessageTime() {
return lastMessageTime;
}
@Override
public void handleError(final Channel channel, final IOException error) {
ProtocolLogger.ROOT_LOGGER.tracef(error, "%s error handling incoming data", this);
try {
channel.close();
} catch (IOException e) {
ProtocolLogger.ROOT_LOGGER.errorClosingChannel(e.getMessage());
}
}
@Override
public void handleEnd(final Channel channel) {
try {
channel.close();
} catch (IOException e) {
ProtocolLogger.ROOT_LOGGER.errorClosingChannel(e.getMessage());
}
}
/**
* Handle a simple ping request.
*
* @param channel the channel
* @param header the protocol header
* @throws IOException for any error
*/
private static void handlePing(final Channel channel, final ManagementProtocolHeader header) throws IOException {
final ManagementProtocolHeader response = new ManagementPongHeader(header.getVersion());
final MessageOutputStream output = channel.writeMessage();
try {
writeHeader(response, output);
output.close();
} finally {
StreamUtils.safeClose(output);
}
}
/**
* Write the management protocol header.
*
* @param header the mgmt protocol header
* @param os the output stream
* @throws IOException
*/
private static void writeHeader(final ManagementProtocolHeader header, final OutputStream os) throws IOException {
final FlushableDataOutput output = FlushableDataOutputImpl.create(os);
header.write(output);
}
}