com.ibm.stocator.fs.common.Utils.java Source code

Introduction

Here is the source code for com.ibm.stocator.fs.common.Utils.java

Source

/**
 * (C) Copyright IBM Corp. 2015, 2016
 *
 * 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 com.ibm.stocator.fs.common;

import java.io.IOException;
import java.net.URI;
import java.util.Properties;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.mapreduce.TaskAttemptID;

import static com.ibm.stocator.fs.common.Constants.HADOOP_ATTEMPT;

public class Utils {

    public static final String BAD_HOST = " hostname '%s' must be in the form container.service";

    /**
     * IOException if the host name is not comply with container.service
     *
     * @param hostname hostname
     * @return IOException
     */
    private static IOException badHostName(String hostname) {
        return new IOException(String.format(BAD_HOST, hostname));
    }

    /**
     * Extracts container name from the container.service
     *
     * @param hostname hostname to split
     * @return the container
     * @throws IOException
     */
    public static String getContainerName(String hostname) throws IOException {
        int i = hostname.indexOf(".");
        if (i <= 0) {
            throw badHostName(hostname);
        }
        return hostname.substring(0, i);
    }

    /**
     * Extracts service name from the container.service
     *
     * @param hostname hostname
     * @return the separated out service name
     * @throws IOException if the hostname was invalid
     */
    public static String getServiceName(String hostname) throws IOException {
        int i = hostname.indexOf(".");
        if (i <= 0) {
            throw badHostName(hostname);
        }
        String service = hostname.substring(i + 1);
        if (service.isEmpty() || service.contains(".")) {
            throw badHostName(hostname);
        }
        return service;
    }

    /**
     * Extract host name from the URI
     *
     * @param uri
     * @return host name
     */
    public static String getHost(URI uri) {
        String host = uri.getHost();
        if (host != null) {
            return host;
        }
        host = uri.toString();
        int sInd = host.indexOf("//") + 2;
        host = host.substring(sInd);
        int eInd = host.indexOf("/");
        host = host.substring(0, eInd);
        return host;
    }

    /**
     * Get a mandatory configuration option
     *
     * @param props property set
     * @param key key
     * @return value of the configuration
     * @throws IOException if there was no match for the key
     */
    public static String getOption(Properties props, String key) throws IOException {
        String val = props.getProperty(key);
        if (val == null) {
            throw new IOException("Undefined property: " + key);
        }
        return val;
    }

    /**
     * Read key from core-site.xml and parse it to Swift configuration
     *
     * @param conf source configuration
     * @param prefix configuration key prefix
     * @param key key in the configuration file
     * @param props destination property set
     * @param propsKey key in the property set
     * @param required if the key is mandatory
     * @throws IOException if there was no match for the key
     */

    public static void updateProperty(Configuration conf, String prefix, String key, Properties props,
            String propsKey, boolean required) throws IOException {
        String val = conf.get(prefix + key);
        if (required && val == null) {
            throw new IOException("Missing mandatory configuration: " + key);
        }
        if (val != null) {
            props.setProperty(propsKey, val.trim());
        }
    }

    /**
     * Extract Hadoop Task ID from path
     * @param path
     * @return task id
     */
    public static String extractTaskID(String path) {
        if (path.contains(HADOOP_ATTEMPT)) {
            String prf = path.substring(path.indexOf(HADOOP_ATTEMPT));
            if (prf.contains("/")) {
                return TaskAttemptID.forName(prf.substring(0, prf.indexOf("/"))).toString();
            }
            return TaskAttemptID.forName(prf).toString();
        }
        return null;
    }

}