gobblin.compaction.HdfsIO.java Source code

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Here is the source code for gobblin.compaction.HdfsIO.java

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/* (c) 2015 LinkedIn Corp. All rights reserved.
 *
 * 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.
 */

package gobblin.compaction;

import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.Set;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.common.collect.ImmutableSet;

/**
 * Management for HDFS reads and writes.
 *
 * @author ziliu
 */
public abstract class HdfsIO {
    private static final Logger LOG = LoggerFactory.getLogger(HdfsIO.class);

    private static final String HDFS_URI = "hdfs.uri";
    private static final String HDFS_URI_DEFAULT = "hdfs://localhost:9000";
    private static final String HADOOP_CONFIGFILE_ = "hadoop.configfile.";
    private static final String HDFS_URI_HADOOP1 = "fs.default.name";
    private static final String HDFS_URI_HADOOP2 = "fs.defaultFS";
    private static final String HADOOP_VERSION = "hadoop.version";
    private static final String HADOOP_VERSION_DEFAULT = "2";
    private static final Set<Integer> VALID_HADOOP_VERSIONS = ImmutableSet.<Integer>builder().add(1).add(2).build();

    protected final String filePathInHdfs;
    protected final FileSystem fileSystem;

    public HdfsIO(String filePathInHdfs) throws IOException {
        this.filePathInHdfs = filePathInHdfs;
        this.fileSystem = getFileSystem();
    }

    private static String getHdfsUriHadoopPropertyName() {
        int hadoopVersion = getHadoopVersion();
        if (hadoopVersion == 1) {
            return HDFS_URI_HADOOP1;
        } else if (hadoopVersion == 2) {
            return HDFS_URI_HADOOP2;
        } else {
            String message = hadoopVersion + " is not a valid Hadoop version.";
            LOG.error(message);
            throw new RuntimeException(message);
        }
    }

    private static int getHadoopVersion() {
        int hadoopVersion = Integer
                .parseInt(CompactionRunner.properties.getProperty(HADOOP_VERSION, HADOOP_VERSION_DEFAULT));
        if (!VALID_HADOOP_VERSIONS.contains(hadoopVersion)) {
            String message = hadoopVersion + " is not a valid Hadoop version.";
            LOG.error(message);
            throw new RuntimeException(message);
        }
        return hadoopVersion;
    }

    protected static FileSystem getFileSystem() throws IOException {
        Configuration conf = getConfiguration();
        return FileSystem.get(conf);
    }

    protected static Configuration getConfiguration() throws FileNotFoundException {
        Configuration conf = new Configuration();
        addResourceToConf(conf);
        return conf;
    }

    private static void addResourceToConf(Configuration conf) {
        conf.setStrings(getHdfsUriHadoopPropertyName(), HDFS_URI_DEFAULT);
        addHadoopConfigPropertiesToConf(conf);
        if (CompactionRunner.properties.containsKey(HDFS_URI)) {
            conf.setStrings(getHdfsUriHadoopPropertyName(), CompactionRunner.properties.getProperty(HDFS_URI));
        }
    }

    private static void addHadoopConfigPropertiesToConf(Configuration conf) {
        Set<String> propertyNames = CompactionRunner.properties.stringPropertyNames();
        for (String propertyName : propertyNames) {
            if (propertyName.startsWith(HADOOP_CONFIGFILE_)) {
                String hadoopConfigFile = CompactionRunner.properties.getProperty(propertyName);
                conf.addResource(hadoopConfigFile);
                LOG.info("Added Hadoop Config File: " + hadoopConfigFile);
            }
        }
    }

    public static String getHdfsUri() {
        return CompactionRunner.properties.getProperty(HDFS_URI, HDFS_URI_DEFAULT);
    }
}