ApnProxyRemoteForwardHandler.java

/*
 * Copyright (c) 2014 The APN-PROXY Project
 *
 * The APN-PROXY Project 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 com.xx_dev.apn.proxy;

import com.xx_dev.apn.proxy.utils.LoggerUtil;
import io.netty.channel.*;
import io.netty.handler.codec.http.HttpHeaders;
import io.netty.handler.codec.http.HttpObject;
import io.netty.handler.codec.http.HttpResponse;
import org.apache.log4j.Logger;

/**
 * @author xmx
 * @version $Id: com.xx_dev.apn.proxy.ApnProxyRemoteForwardHandler 14-1-8 16:13 (xmx) Exp $
 */
public class ApnProxyRemoteForwardHandler extends ChannelInboundHandlerAdapter {

    private static final Logger logger = Logger.getLogger(ApnProxyRemoteForwardHandler.class);

    private static final Logger forwardRestLogger = Logger.getLogger("FORWARD_REST_LOGGER");

    public static final String HANDLER_NAME = "apnproxy.remote.forward";

    private Channel uaChannel;

    private RemoteChannelInactiveCallback remoteChannelInactiveCallback;

    private int remainMsgCount = 0;

    public ApnProxyRemoteForwardHandler(Channel uaChannel,
                                        RemoteChannelInactiveCallback remoteChannelInactiveCallback) {
        this.uaChannel = uaChannel;
        this.remoteChannelInactiveCallback = remoteChannelInactiveCallback;
    }

    @Override
    public void channelActive(ChannelHandlerContext remoteChannelCtx) throws Exception {
        LoggerUtil.debug(logger, uaChannel.attr(ApnProxyConnectionAttribute.ATTRIBUTE_KEY), "Remote channel active");
        remoteChannelCtx.read();
    }

    public void channelRead(final ChannelHandlerContext remoteChannelCtx, final Object msg) throws Exception {
        LoggerUtil.debug(logger, uaChannel.attr(ApnProxyConnectionAttribute.ATTRIBUTE_KEY), "Remote msg", msg);

        remainMsgCount++;

        if (remainMsgCount <= 5) {
            remoteChannelCtx.read();
        }


        HttpObject ho = (HttpObject) msg;


        if (ho instanceof HttpResponse) {
            HttpResponse httpResponse = (HttpResponse) ho;

            LoggerUtil.info(forwardRestLogger, uaChannel.attr(ApnProxyConnectionAttribute.ATTRIBUTE_KEY), httpResponse.getStatus(), httpResponse.getProtocolVersion());


            httpResponse.headers().set(HttpHeaders.Names.CONNECTION, HttpHeaders.Values.KEEP_ALIVE);
            httpResponse.headers().set("Proxy-Connection", HttpHeaders.Values.KEEP_ALIVE);
        }

        if (uaChannel.isActive()) {
            uaChannel.writeAndFlush(ho).addListener(new ChannelFutureListener() {
                @Override
                public void operationComplete(ChannelFuture future) throws Exception {
                    LoggerUtil.debug(logger, uaChannel.attr(ApnProxyConnectionAttribute.ATTRIBUTE_KEY), "Write to UA finished: " + future.isSuccess());
                    if (future.isSuccess()) {
                        remainMsgCount--;
                        remoteChannelCtx.read();
                        LoggerUtil.debug(logger, uaChannel.attr(ApnProxyConnectionAttribute.ATTRIBUTE_KEY), "Fire read again");
                    } else {
                        remoteChannelCtx.close();
                    }
                }
            });
        } else {
            remoteChannelCtx.close();
        }
    }

    @Override
    public void channelInactive(final ChannelHandlerContext remoteChannelCtx) throws Exception {
        LoggerUtil.debug(logger, uaChannel.attr(ApnProxyConnectionAttribute.ATTRIBUTE_KEY), "Remote channel inactive");

        final String remoteAddr = uaChannel.attr(ApnProxyConnectionAttribute.ATTRIBUTE_KEY).get().getRemote().getRemoteAddr();

        remoteChannelInactiveCallback.remoteChannelInactive(uaChannel, remoteAddr);

        remoteChannelCtx.fireChannelInactive();

    }

    @Override
    public void exceptionCaught(ChannelHandlerContext remoteChannelCtx, Throwable cause) throws Exception {
        logger.error(cause.getMessage() + uaChannel.attr(ApnProxyConnectionAttribute.ATTRIBUTE_KEY), cause);
        remoteChannelCtx.close();
    }

    public interface RemoteChannelInactiveCallback {
        public void remoteChannelInactive(Channel uaChannel,
                                          String remoeAddr) throws Exception;
    }

}