org.apache.hadoop.hive.ql.hooks.PostExecOrcFileDump.java Source code

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Here is the source code for org.apache.hadoop.hive.ql.hooks.PostExecOrcFileDump.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
 * <p/>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p/>
 * 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.hadoop.hive.ql.hooks;

import java.io.IOException;
import java.io.PrintStream;
import java.util.List;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.PathFilter;
import org.apache.hadoop.hive.conf.HiveConf;
import org.apache.hadoop.hive.ql.QueryPlan;
import org.apache.hadoop.hive.ql.exec.FetchTask;
import org.apache.hadoop.hive.ql.io.FileFormatException;
import org.apache.hadoop.hive.ql.io.orc.FileDump;
import org.apache.hadoop.hive.ql.io.orc.OrcFile;
import org.apache.hadoop.hive.ql.plan.FetchWork;
import org.apache.hadoop.hive.ql.session.SessionState;
import org.apache.hadoop.hive.shims.ShimLoader;

import com.google.common.collect.Lists;

/**
 * Post exec hook to print orc file dump for files that will be read by fetch task. The file dump
 * output will be printed before fetch task output. It also prints the row index for the 1st column
 * in the file just to verify the impact of bloom filter fpp.
 */
public class PostExecOrcFileDump implements ExecuteWithHookContext {
    private static final Log LOG = LogFactory.getLog(PostExecOrcFileDump.class.getName());

    private static final PathFilter hiddenFileFilter = new PathFilter() {
        public boolean accept(Path p) {
            String name = p.getName();
            return !name.startsWith("_") && !name.startsWith(".");
        }
    };

    @Override
    public void run(HookContext hookContext) throws Exception {
        assert (hookContext.getHookType() == HookContext.HookType.POST_EXEC_HOOK);
        HiveConf conf = hookContext.getConf();

        LOG.info("Executing post execution hook to print orc file dump..");
        QueryPlan plan = hookContext.getQueryPlan();
        if (plan == null) {
            return;
        }

        FetchTask fetchTask = plan.getFetchTask();
        if (fetchTask != null) {
            SessionState ss = SessionState.get();
            SessionState.LogHelper console = ss.getConsole();

            // file dump should write to session state console's error stream
            PrintStream old = System.out;
            System.setOut(console.getErrStream());

            FetchWork fetchWork = fetchTask.getWork();
            boolean partitionedTable = fetchWork.isPartitioned();
            List<Path> directories;
            if (partitionedTable) {
                LOG.info("Printing orc file dump for files from partitioned directory..");
                directories = fetchWork.getPartDir();
            } else {
                LOG.info("Printing orc file dump for files from table directory..");
                directories = Lists.newArrayList();
                directories.add(fetchWork.getTblDir());
            }

            for (Path dir : directories) {
                FileSystem fs = dir.getFileSystem(conf);
                List<FileStatus> fileList = ShimLoader.getHadoopShims().listLocatedStatus(fs, dir,
                        hiddenFileFilter);

                for (FileStatus fileStatus : fileList) {
                    LOG.info("Printing orc file dump for " + fileStatus.getPath());
                    if (fileStatus.getLen() > 0) {
                        try {
                            // just creating orc reader is going to do sanity checks to make sure its valid ORC file
                            OrcFile.createReader(fs, fileStatus.getPath());
                            console.printError("-- BEGIN ORC FILE DUMP --");
                            FileDump.main(new String[] { fileStatus.getPath().toString(), "--rowindex=1" });
                            console.printError("-- END ORC FILE DUMP --");
                        } catch (FileFormatException e) {
                            LOG.warn("File " + fileStatus.getPath() + " is not ORC. Skip printing orc file dump");
                        } catch (IOException e) {
                            LOG.warn("Skip printing orc file dump. Exception: " + e.getMessage());
                        }
                    } else {
                        LOG.warn("Zero length file encountered. Skip printing orc file dump.");
                    }
                }
            }

            // restore the old out stream
            System.out.flush();
            System.setOut(old);
        }
    }

}