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/** * Copyright (C) 2010-2013 Alibaba Group Holding Limited * * Licensed 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.alibaba.rocketmq.broker.processor; import io.netty.channel.ChannelFuture; import io.netty.channel.ChannelFutureListener; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.FileRegion; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.alibaba.rocketmq.broker.BrokerController; import com.alibaba.rocketmq.broker.pagecache.OneMessageTransfer; import com.alibaba.rocketmq.broker.pagecache.QueryMessageTransfer; import com.alibaba.rocketmq.common.constant.LoggerName; import com.alibaba.rocketmq.common.protocol.RequestCode; import com.alibaba.rocketmq.common.protocol.ResponseCode; import com.alibaba.rocketmq.common.protocol.header.QueryMessageRequestHeader; import com.alibaba.rocketmq.common.protocol.header.QueryMessageResponseHeader; import com.alibaba.rocketmq.common.protocol.header.ViewMessageRequestHeader; import com.alibaba.rocketmq.remoting.exception.RemotingCommandException; import com.alibaba.rocketmq.remoting.netty.NettyRequestProcessor; import com.alibaba.rocketmq.remoting.protocol.RemotingCommand; import com.alibaba.rocketmq.store.QueryMessageResult; import com.alibaba.rocketmq.store.SelectMapedBufferResult; /** * ?? * * @author shijia.wxr<vintage.wang@gmail.com> * @since 2013-7-26 */ public class QueryMessageProcessor implements NettyRequestProcessor { private static final Logger log = LoggerFactory.getLogger(LoggerName.BrokerLoggerName); private final BrokerController brokerController; public QueryMessageProcessor(final BrokerController brokerController) { this.brokerController = brokerController; } @Override public RemotingCommand processRequest(ChannelHandlerContext ctx, RemotingCommand request) throws RemotingCommandException { switch (request.getCode()) { case RequestCode.QUERY_MESSAGE: return this.queryMessage(ctx, request); case RequestCode.VIEW_MESSAGE_BY_ID: return this.viewMessageById(ctx, request); default: break; } return null; } public RemotingCommand queryMessage(ChannelHandlerContext ctx, RemotingCommand request) throws RemotingCommandException { final RemotingCommand response = RemotingCommand.createResponseCommand(QueryMessageResponseHeader.class); final QueryMessageResponseHeader responseHeader = (QueryMessageResponseHeader) response.readCustomHeader(); final QueryMessageRequestHeader requestHeader = (QueryMessageRequestHeader) request .decodeCommandCustomHeader(QueryMessageRequestHeader.class); // sendfile? response.setOpaque(request.getOpaque()); final QueryMessageResult queryMessageResult = this.brokerController.getMessageStore().queryMessage( requestHeader.getTopic(), requestHeader.getKey(), requestHeader.getMaxNum(), requestHeader.getBeginTimestamp(), requestHeader.getEndTimestamp()); assert queryMessageResult != null; responseHeader.setIndexLastUpdatePhyoffset(queryMessageResult.getIndexLastUpdatePhyoffset()); responseHeader.setIndexLastUpdateTimestamp(queryMessageResult.getIndexLastUpdateTimestamp()); // ? if (queryMessageResult.getBufferTotalSize() > 0) { response.setCode(ResponseCode.SUCCESS); response.setRemark(null); try { FileRegion fileRegion = new QueryMessageTransfer( response.encodeHeader(queryMessageResult.getBufferTotalSize()), queryMessageResult); ctx.channel().writeAndFlush(fileRegion).addListener(new ChannelFutureListener() { @Override public void operationComplete(ChannelFuture future) throws Exception { queryMessageResult.release(); if (!future.isSuccess()) { log.error("transfer query message by pagecache failed, ", future.cause()); } } }); } catch (Throwable e) { log.error("", e); queryMessageResult.release(); } return null; } response.setCode(ResponseCode.QUERY_NOT_FOUND); response.setRemark("can not find message, maybe time range not correct"); return response; } public RemotingCommand viewMessageById(ChannelHandlerContext ctx, RemotingCommand request) throws RemotingCommandException { final RemotingCommand response = RemotingCommand.createResponseCommand(null); final ViewMessageRequestHeader requestHeader = (ViewMessageRequestHeader) request .decodeCommandCustomHeader(ViewMessageRequestHeader.class); // sendfile? response.setOpaque(request.getOpaque()); final SelectMapedBufferResult selectMapedBufferResult = this.brokerController.getMessageStore() .selectOneMessageByOffset(requestHeader.getOffset()); if (selectMapedBufferResult != null) { response.setCode(ResponseCode.SUCCESS); response.setRemark(null); try { FileRegion fileRegion = new OneMessageTransfer( response.encodeHeader(selectMapedBufferResult.getSize()), selectMapedBufferResult); ctx.channel().writeAndFlush(fileRegion).addListener(new ChannelFutureListener() { @Override public void operationComplete(ChannelFuture future) throws Exception { selectMapedBufferResult.release(); if (!future.isSuccess()) { log.error("transfer one message by pagecache failed, ", future.cause()); } } }); } catch (Throwable e) { log.error("", e); selectMapedBufferResult.release(); } return null; } else { response.setCode(ResponseCode.SYSTEM_ERROR); response.setRemark("can not find message by the offset, " + requestHeader.getOffset()); } return response; } }