org.apache.ambari.servicemonitor.utils.DFSUtils.java Source code

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Here is the source code for org.apache.ambari.servicemonitor.utils.DFSUtils.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.ambari.servicemonitor.utils;

import org.apache.ambari.servicemonitor.HadoopKeys;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.hdfs.DistributedFileSystem;
import org.apache.hadoop.hdfs.MiniDFSCluster;
import org.apache.hadoop.mapred.JobConf;
import org.apache.hadoop.mapred.MiniMRCluster;

import java.io.File;
import java.io.IOException;
import java.net.URI;
import java.util.Iterator;
import java.util.Map;
import java.util.TreeSet;

public final class DFSUtils {

    private static final Log LOG = LogFactory.getLog(DFSUtils.class);
    public static final String DFS_CLIENT_RETRY_POLICY_ENABLED = "dfs.client.retry.policy.enabled";
    public static final String IPC_CLIENT_CONNECT_MAX_RETRIES = "ipc.client.connect.max.retries";

    private DFSUtils() {
    }

    /**
     * Get an HDFS URI
     * @param conf configuration
     * @return the URI
     * @throws IOException
     */
    public static URI getHDFSUri(Configuration conf) throws IOException {
        URI uri = FileSystem.getDefaultUri(conf);
        if (!uri.getScheme().equals("hdfs")) {
            throw new IOException("Filesystem is not HDFS " + uri);
        }
        return uri;
    }

    /**
     * Create a DFS Instance that is not cached
     *
     * @param conf the configuration to work with
     * @return the DFS Instance
     * @throws IOException on any IO problem
     * @throws ExitMainException if the default FS isn't HDFS
     */
    public static DistributedFileSystem createUncachedDFS(Configuration conf) throws IOException {
        conf.setBoolean(HadoopKeys.FS_HDFS_IMPL_DISABLE_CACHE, true);
        FileSystem filesys = FileSystem.get(conf);
        URI fsURI = filesys.getUri();
        if (!(filesys instanceof DistributedFileSystem)) {
            throw new ExitMainException(-1, "Filesystem is not HDFS " + fsURI);
        }
        return (DistributedFileSystem) filesys;
    }

    /**
     * Take a configuration and add the parameters to make it blocking
     *
     * @param conf configuration to patch
     */
    public static void makeDfsCallsBlocking(Configuration conf) {
        conf.setBoolean(DFS_CLIENT_RETRY_POLICY_ENABLED, true);
    }

    /**
     * Take a configuration and add the parameters to make it blocking
     *
     * @param conf configuration to patch
     */
    public static void makeDfsCallsNonBlocking(Configuration conf) {
        conf.setBoolean(DFS_CLIENT_RETRY_POLICY_ENABLED, false);
        conf.setInt(IPC_CLIENT_CONNECT_MAX_RETRIES, 0);
    }

    /**
     * create a default cluster
     *
     * @return a cluster
     * @throws IOException
     */
    public static MiniDFSCluster createCluster() throws IOException {
        Configuration conf = new Configuration();
        int numDataNodes = 3;
        String testDataDirPath = "target/test/data" + System.currentTimeMillis();
        return createCluster(conf, testDataDirPath, numDataNodes);
    }

    public static MiniDFSCluster createCluster(Configuration conf, String dataDirPath, int numDataNodes)
            throws IOException {
        File testDataDir = new File(dataDirPath);
        System.setProperty("test.build.data", testDataDir.getAbsolutePath());
        return new MiniDFSCluster(conf, numDataNodes, true, null);
    }

    public static MiniDFSCluster destroyCluster(MiniDFSCluster dfsCluster) {
        if (dfsCluster != null) {
            try {
                dfsCluster.shutdown();
            } catch (Exception e) {
                LOG.warn("Exception when destroying cluster: " + e, e);
            }
        }
        return null;
    }

    public static MiniMRCluster createMRCluster(JobConf conf, String fsURI) throws IOException {
        String logdir = System.getProperty("java.io.tmpdir") + "/mrcluster/logs";
        System.setProperty("hadoop.log.dir", logdir);
        conf.set("hadoop.job.history.location", "file:///" + logdir + "/history");
        conf.set(FileSystem.FS_DEFAULT_NAME_KEY, fsURI);
        return new MiniMRCluster(3, fsURI, 1, null, null, conf);
    }

    public static MiniMRCluster destroyMRCluster(MiniMRCluster mrCluster) {
        if (mrCluster != null) {
            try {
                mrCluster.shutdown();
            } catch (Exception e) {
                LOG.warn("Exception when destroying cluster: " + e, e);
            }
        }
        return null;
    }

    /**
     * Close any non-null FS
     *
     * @param hdfs filesystem
     * @return null, always
     */
    public static DistributedFileSystem closeDFS(FileSystem hdfs) {
        if (hdfs != null) {
            try {
                hdfs.close();
            } catch (IOException ignore) {

            }
        }
        return null;
    }

    public static TreeSet<String> sortedConfigList(Configuration conf) {
        TreeSet<String> keys = new TreeSet<String>();
        Iterator<Map.Entry<String, String>> iterator = conf.iterator();
        while (iterator.hasNext()) {
            Map.Entry<String, String> next = iterator.next();
            keys.add(next.getKey());
        }
        return keys;
    }
}