/*
* Licensed to Elasticsearch under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
* ownership. Elasticsearch 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.elasticsearch.transport.netty;
import org.elasticsearch.ElasticsearchIllegalStateException;
import org.elasticsearch.Version;
import org.elasticsearch.common.component.Lifecycle;
import org.elasticsearch.common.compress.Compressor;
import org.elasticsearch.common.compress.CompressorFactory;
import org.elasticsearch.common.io.ThrowableObjectInputStream;
import org.elasticsearch.common.io.stream.CachedStreamInput;
import org.elasticsearch.common.io.stream.StreamInput;
import org.elasticsearch.common.logging.ESLogger;
import org.elasticsearch.common.transport.InetSocketTransportAddress;
import org.elasticsearch.common.util.concurrent.AbstractRunnable;
import org.elasticsearch.threadpool.ThreadPool;
import org.elasticsearch.transport.*;
import org.elasticsearch.transport.support.TransportStatus;
import org.jboss.netty.buffer.ChannelBuffer;
import org.jboss.netty.channel.*;
import java.io.IOException;
import java.net.InetSocketAddress;
/**
* A handler (must be the last one!) that does size based frame decoding and forwards the actual message
* to the relevant action.
*/
public class MessageChannelHandler extends SimpleChannelUpstreamHandler {
protected final ESLogger logger;
protected final ThreadPool threadPool;
protected final TransportServiceAdapter transportServiceAdapter;
protected final NettyTransport transport;
public MessageChannelHandler(NettyTransport transport, ESLogger logger) {
this.threadPool = transport.threadPool();
this.transportServiceAdapter = transport.transportServiceAdapter();
this.transport = transport;
this.logger = logger;
}
@Override
public void writeComplete(ChannelHandlerContext ctx, WriteCompletionEvent e) throws Exception {
transportServiceAdapter.sent(e.getWrittenAmount());
super.writeComplete(ctx, e);
}
@Override
public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) throws Exception {
Object m = e.getMessage();
if (!(m instanceof ChannelBuffer)) {
ctx.sendUpstream(e);
return;
}
ChannelBuffer buffer = (ChannelBuffer) m;
int size = buffer.getInt(buffer.readerIndex() - 4);
transportServiceAdapter.received(size + 6);
// we have additional bytes to read, outside of the header
boolean hasMessageBytesToRead = (size - (NettyHeader.HEADER_SIZE - 6)) != 0;
int markedReaderIndex = buffer.readerIndex();
int expectedIndexReader = markedReaderIndex + size;
// netty always copies a buffer, either in NioWorker in its read handler, where it copies to a fresh
// buffer, or in the cumlation buffer, which is cleaned each time
StreamInput streamIn = ChannelBufferStreamInputFactory.create(buffer, size);
long requestId = buffer.readLong();
byte status = buffer.readByte();
Version version = Version.fromId(buffer.readInt());
StreamInput wrappedStream;
if (TransportStatus.isCompress(status) && hasMessageBytesToRead && buffer.readable()) {
Compressor compressor = CompressorFactory.compressor(buffer);
if (compressor == null) {
int maxToRead = Math.min(buffer.readableBytes(), 10);
int offset = buffer.readerIndex();
StringBuilder sb = new StringBuilder("stream marked as compressed, but no compressor found, first [").append(maxToRead).append("] content bytes out of [").append(buffer.readableBytes()).append("] readable bytes with message size [").append(size).append("] ").append("] are [");
for (int i = 0; i < maxToRead; i++) {
sb.append(buffer.getByte(offset + i)).append(",");
}
sb.append("]");
throw new ElasticsearchIllegalStateException(sb.toString());
}
wrappedStream = CachedStreamInput.cachedHandlesCompressed(compressor, streamIn);
} else {
wrappedStream = CachedStreamInput.cachedHandles(streamIn);
}
wrappedStream.setVersion(version);
if (TransportStatus.isRequest(status)) {
String action = handleRequest(ctx.getChannel(), wrappedStream, requestId, version);
if (buffer.readerIndex() != expectedIndexReader) {
if (buffer.readerIndex() < expectedIndexReader) {
logger.warn("Message not fully read (request) for [{}] and action [{}], resetting", requestId, action);
} else {
logger.warn("Message read past expected size (request) for [{}] and action [{}], resetting", requestId, action);
}
buffer.readerIndex(expectedIndexReader);
}
} else {
TransportResponseHandler handler = transportServiceAdapter.remove(requestId);
// ignore if its null, the adapter logs it
if (handler != null) {
if (TransportStatus.isError(status)) {
handlerResponseError(wrappedStream, handler);
} else {
handleResponse(ctx.getChannel(), wrappedStream, handler);
}
} else {
// if its null, skip those bytes
buffer.readerIndex(markedReaderIndex + size);
}
if (buffer.readerIndex() != expectedIndexReader) {
if (buffer.readerIndex() < expectedIndexReader) {
logger.warn("Message not fully read (response) for [{}] handler {}, error [{}], resetting", requestId, handler, TransportStatus.isError(status));
} else {
logger.warn("Message read past expected size (response) for [{}] handler {}, error [{}], resetting", requestId, handler, TransportStatus.isError(status));
}
buffer.readerIndex(expectedIndexReader);
}
}
wrappedStream.close();
}
protected void handleResponse(Channel channel, StreamInput buffer, final TransportResponseHandler handler) {
final TransportResponse response = handler.newInstance();
response.remoteAddress(new InetSocketTransportAddress((InetSocketAddress) channel.getRemoteAddress()));
response.remoteAddress();
try {
response.readFrom(buffer);
} catch (Throwable e) {
handleException(handler, new TransportSerializationException("Failed to deserialize response of type [" + response.getClass().getName() + "]", e));
return;
}
try {
if (handler.executor() == ThreadPool.Names.SAME) {
//noinspection unchecked
handler.handleResponse(response);
} else {
threadPool.executor(handler.executor()).execute(new ResponseHandler(handler, response));
}
} catch (Throwable e) {
handleException(handler, new ResponseHandlerFailureTransportException(e));
}
}
private void handlerResponseError(StreamInput buffer, final TransportResponseHandler handler) {
Throwable error;
try {
ThrowableObjectInputStream ois = new ThrowableObjectInputStream(buffer, transport.settings().getClassLoader());
error = (Throwable) ois.readObject();
} catch (Throwable e) {
error = new TransportSerializationException("Failed to deserialize exception response from stream", e);
}
handleException(handler, error);
}
private void handleException(final TransportResponseHandler handler, Throwable error) {
if (!(error instanceof RemoteTransportException)) {
error = new RemoteTransportException(error.getMessage(), error);
}
final RemoteTransportException rtx = (RemoteTransportException) error;
if (handler.executor() == ThreadPool.Names.SAME) {
try {
handler.handleException(rtx);
} catch (Throwable e) {
logger.error("failed to handle exception response [{}]", e, handler);
}
} else {
threadPool.executor(handler.executor()).execute(new Runnable() {
@Override
public void run() {
try {
handler.handleException(rtx);
} catch (Throwable e) {
logger.error("failed to handle exception response [{}]", e, handler);
}
}
});
}
}
protected String handleRequest(Channel channel, StreamInput buffer, long requestId, Version version) throws IOException {
final String action = buffer.readString();
final NettyTransportChannel transportChannel = new NettyTransportChannel(transport, action, channel, requestId, version);
try {
final TransportRequestHandler handler = transportServiceAdapter.handler(action, version);
if (handler == null) {
throw new ActionNotFoundTransportException(action);
}
final TransportRequest request = handler.newInstance();
request.remoteAddress(new InetSocketTransportAddress((InetSocketAddress) channel.getRemoteAddress()));
request.readFrom(buffer);
if (handler.executor() == ThreadPool.Names.SAME) {
//noinspection unchecked
handler.messageReceived(request, transportChannel);
} else {
threadPool.executor(handler.executor()).execute(new RequestHandler(handler, request, transportChannel, action));
}
} catch (Throwable e) {
try {
transportChannel.sendResponse(e);
} catch (IOException e1) {
logger.warn("Failed to send error message back to client for action [" + action + "]", e);
logger.warn("Actual Exception", e1);
}
}
return action;
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, ExceptionEvent e) throws Exception {
transport.exceptionCaught(ctx, e);
}
class ResponseHandler implements Runnable {
private final TransportResponseHandler handler;
private final TransportResponse response;
public ResponseHandler(TransportResponseHandler handler, TransportResponse response) {
this.handler = handler;
this.response = response;
}
@SuppressWarnings({"unchecked"})
@Override
public void run() {
try {
handler.handleResponse(response);
} catch (Throwable e) {
handleException(handler, new ResponseHandlerFailureTransportException(e));
}
}
}
class RequestHandler extends AbstractRunnable {
private final TransportRequestHandler handler;
private final TransportRequest request;
private final NettyTransportChannel transportChannel;
private final String action;
public RequestHandler(TransportRequestHandler handler, TransportRequest request, NettyTransportChannel transportChannel, String action) {
this.handler = handler;
this.request = request;
this.transportChannel = transportChannel;
this.action = action;
}
@SuppressWarnings({"unchecked"})
@Override
protected void doRun() throws Exception {
handler.messageReceived(request, transportChannel);
}
@Override
public boolean isForceExecution() {
return handler.isForceExecution();
}
@Override
public void onFailure(Throwable e) {
if (transport.lifecycleState() == Lifecycle.State.STARTED) {
// we can only send a response transport is started....
try {
transportChannel.sendResponse(e);
} catch (Throwable e1) {
logger.warn("Failed to send error message back to client for action [" + action + "]", e1);
logger.warn("Actual Exception", e);
}
}
}
}
}