nl.surfsara.warcexamples.hdfs.Headers.java Source code

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Here is the source code for nl.surfsara.warcexamples.hdfs.Headers.java

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/**
 * Copyright 2014 SURFsara
 *
 * 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 nl.surfsara.warcexamples.hdfs;

import java.io.IOException;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.security.UserGroupInformation;

/**
 * Runnable class that uses an existing Kerberos tgt to read a specified warc,
 * wet or wat file from HDFS and dumps the headers for each WarcRecord.
 * 
 * @author mathijs.kattenberg@surfsara.nl
 */
public class Headers implements Runnable {
    private String path;

    public Headers(String path) {
        this.path = path;
    }

    @Override
    public void run() {
        // PropertyConfigurator.configure("log4jconfig.properties");
        final Configuration conf = new Configuration();
        // The core-site.xml and hdfs-site.xml are cluster specific. If you wish to use this on other clusters adapt the files as needed.
        conf.addResource(
                Headers.class.getResourceAsStream("/nl/surfsara/warcexamples/hdfs/resources/core-site.xml"));
        conf.addResource(
                Headers.class.getResourceAsStream("/nl/surfsara/warcexamples/hdfs/resources/hdfs-site.xml"));

        conf.set("hadoop.security.authentication", "kerberos");
        conf.set("hadoop.security.authorization", "true");

        System.setProperty("java.security.krb5.realm", "CUA.SURFSARA.NL");
        System.setProperty("java.security.krb5.kdc", "kdc.hathi.surfsara.nl");

        UserGroupInformation.setConfiguration(conf);

        UserGroupInformation loginUser;
        try {
            loginUser = UserGroupInformation.getLoginUser();
            System.out.println("Logged in as: " + loginUser.getUserName());
            PrintHeaders printHeaders = new PrintHeaders(conf, path);
            loginUser.doAs(printHeaders);
        } catch (IOException e) {
            // Just dump the error..
            e.printStackTrace();
        }
    }

}