org.apache.tajo.worker.dataserver.retriever.AdvancedDataRetriever.java Source code

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Here is the source code for org.apache.tajo.worker.dataserver.retriever.AdvancedDataRetriever.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.tajo.worker.dataserver.retriever;

import com.google.common.collect.Lists;
import com.google.common.collect.Maps;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.tajo.ExecutionBlockId;
import org.apache.tajo.TaskAttemptId;
import org.apache.tajo.TaskId;
import org.apache.tajo.util.TajoIdUtils;
import org.apache.tajo.worker.dataserver.FileAccessForbiddenException;
import org.jboss.netty.channel.ChannelHandlerContext;
import org.jboss.netty.handler.codec.http.HttpRequest;
import org.jboss.netty.handler.codec.http.QueryStringDecoder;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;

public class AdvancedDataRetriever implements DataRetriever {
    private final Log LOG = LogFactory.getLog(AdvancedDataRetriever.class);
    private final Map<String, RetrieverHandler> handlerMap = Maps.newConcurrentMap();

    public AdvancedDataRetriever() {
    }

    public void register(TaskAttemptId id, RetrieverHandler handler) {
        synchronized (handlerMap) {
            if (!handlerMap.containsKey(id.toString())) {
                handlerMap.put(id.toString(), handler);
            }
        }
    }

    public void unregister(TaskAttemptId id) {
        synchronized (handlerMap) {
            if (handlerMap.containsKey(id.toString())) {
                handlerMap.remove(id.toString());
            }
        }
    }

    /* (non-Javadoc)
     * @see org.apache.tajo.worker.dataserver.retriever.DataRetriever#handle(org.jboss.netty.channel.ChannelHandlerContext, org.jboss.netty.handler.codec.http.HttpRequest)
     */
    @Override
    public FileChunk[] handle(ChannelHandlerContext ctx, HttpRequest request) throws IOException {

        final Map<String, List<String>> params = new QueryStringDecoder(request.getUri()).getParameters();

        if (!params.containsKey("qid")) {
            throw new FileNotFoundException("No such qid: " + params.containsKey("qid"));
        }

        if (params.containsKey("sid")) {
            List<FileChunk> chunks = Lists.newArrayList();
            List<String> qids = splitMaps(params.get("qid"));
            for (String qid : qids) {
                String[] ids = qid.split("_");
                ExecutionBlockId suid = TajoIdUtils.createExecutionBlockId(params.get("sid").get(0));
                TaskId quid = new TaskId(suid, Integer.parseInt(ids[0]));
                TaskAttemptId attemptId = new TaskAttemptId(quid, Integer.parseInt(ids[1]));
                RetrieverHandler handler = handlerMap.get(attemptId.toString());
                FileChunk chunk = handler.get(params);
                chunks.add(chunk);
            }
            return chunks.toArray(new FileChunk[chunks.size()]);
        } else {
            RetrieverHandler handler = handlerMap.get(params.get("qid").get(0));
            FileChunk chunk = handler.get(params);
            if (chunk == null) {
                if (params.containsKey("qid")) { // if there is no content corresponding to the query
                    return null;
                } else { // if there is no
                    throw new FileNotFoundException("No such a file corresponding to " + params.get("qid"));
                }
            }

            File file = chunk.getFile();
            if (file.isHidden() || !file.exists()) {
                throw new FileNotFoundException("No such file: " + file.getAbsolutePath());
            }
            if (!file.isFile()) {
                throw new FileAccessForbiddenException(file.getAbsolutePath() + " is not file");
            }

            return new FileChunk[] { chunk };
        }
    }

    private List<String> splitMaps(List<String> qids) {
        if (null == qids) {
            LOG.error("QueryId is EMPTY");
            return null;
        }

        final List<String> ret = new ArrayList<String>();
        for (String qid : qids) {
            Collections.addAll(ret, qid.split(","));
        }
        return ret;
    }
}