org.apache.giraph.comm.netty.handler.ResponseClientHandler.java Source code

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Here is the source code for org.apache.giraph.comm.netty.handler.ResponseClientHandler.java

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/*
 * 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.giraph.comm.netty.handler;

import org.apache.hadoop.conf.Configuration;
import org.apache.log4j.Logger;

import java.util.concurrent.ConcurrentMap;

import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;
import io.netty.util.ReferenceCountUtil;

import static org.apache.giraph.conf.GiraphConstants.NETTY_SIMULATE_FIRST_RESPONSE_FAILED;

/**
 * Generic handler of responses.
 */
public class ResponseClientHandler extends ChannelInboundHandlerAdapter {
    /** Class logger */
    private static final Logger LOG = Logger.getLogger(ResponseClientHandler.class);
    /** Already dropped first response? (used if dropFirstResponse == true) */
    private static volatile boolean ALREADY_DROPPED_FIRST_RESPONSE = false;
    /** Drop first response (used for simulating failure) */
    private final boolean dropFirstResponse;
    /** Outstanding worker request map */
    private final ConcurrentMap<ClientRequestId, RequestInfo> workerIdOutstandingRequestMap;

    /**
     * Constructor.
     *
     * @param workerIdOutstandingRequestMap Map of worker ids to outstanding
     *                                      requests
     * @param conf Configuration
     */
    public ResponseClientHandler(ConcurrentMap<ClientRequestId, RequestInfo> workerIdOutstandingRequestMap,
            Configuration conf) {
        this.workerIdOutstandingRequestMap = workerIdOutstandingRequestMap;
        dropFirstResponse = NETTY_SIMULATE_FIRST_RESPONSE_FAILED.get(conf);
    }

    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
        if (!(msg instanceof ByteBuf)) {
            throw new IllegalStateException("messageReceived: Got a " + "non-ByteBuf message " + msg);
        }

        ByteBuf buf = (ByteBuf) msg;
        int senderId = -1;
        long requestId = -1;
        int response = -1;
        try {
            senderId = buf.readInt();
            requestId = buf.readLong();
            response = buf.readByte();
        } catch (IndexOutOfBoundsException e) {
            throw new IllegalStateException("channelRead: Got IndexOutOfBoundsException ", e);
        }
        ReferenceCountUtil.release(buf);

        // Simulate a failed response on the first response (if desired)
        if (dropFirstResponse && !ALREADY_DROPPED_FIRST_RESPONSE) {
            LOG.info("messageReceived: Simulating dropped response " + response + " for request " + requestId);
            setAlreadyDroppedFirstResponse();
            synchronized (workerIdOutstandingRequestMap) {
                workerIdOutstandingRequestMap.notifyAll();
            }
            return;
        }

        if (response == 1) {
            LOG.info("messageReceived: Already completed request (taskId = " + senderId + ", requestId = "
                    + requestId + ")");
        } else if (response != 0) {
            throw new IllegalStateException("messageReceived: Got illegal response " + response);
        }

        RequestInfo requestInfo = workerIdOutstandingRequestMap.remove(new ClientRequestId(senderId, requestId));
        if (requestInfo == null) {
            LOG.info("messageReceived: Already received response for (taskId = " + senderId + ", requestId = "
                    + requestId + ")");
        } else {
            if (LOG.isDebugEnabled()) {
                LOG.debug("messageReceived: Completed (taskId = " + senderId + ")" + requestInfo + ".  Waiting on "
                        + workerIdOutstandingRequestMap.size() + " requests");
            }
        }

        // Help NettyClient#waitSomeRequests() to finish faster
        synchronized (workerIdOutstandingRequestMap) {
            workerIdOutstandingRequestMap.notifyAll();
        }
    }

    /**
     * Set already dropped first response flag
     */
    private static void setAlreadyDroppedFirstResponse() {
        ALREADY_DROPPED_FIRST_RESPONSE = true;
    }

    @Override
    public void channelInactive(ChannelHandlerContext ctx) throws Exception {
        if (LOG.isDebugEnabled()) {
            LOG.debug("channelClosed: Closed the channel on " + ctx.channel().remoteAddress());
        }
        ctx.fireChannelInactive();
    }

    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        LOG.warn("exceptionCaught: Channel failed with " + "remote address " + ctx.channel().remoteAddress(),
                cause);
    }
}