org.apache.nutch.admin.GuiConfigUtil.java Source code

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Here is the source code for org.apache.nutch.admin.GuiConfigUtil.java

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/**
 * Copyright 2005 The Apache Software Foundation
 *
 * 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 org.apache.nutch.admin;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.conf.Configured;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.LocalFileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.nutch.util.NutchConfiguration;

/**
 * Bundles some methods to handle configuration files
 */
public class GuiConfigUtil {

    /**
     * Creates a new configuration, then writes the new configuration to the 
     * path
     * @param folder the path of the new configuration
     * @return fresh loaded configuration
     */
    public static Configuration loadNewConfiguration(Path folder) throws IOException {
        Configuration configuration = NutchConfiguration.create();
        configure(configuration, folder);
        return configuration;
    }

    /**
     * Creates a configuration folder and stores nutch's configuration files 
     * in this folder.
     * 
     * @param instanceFolder
     * @throws IOException
     */
    public static void createConfiguration(Path instanceFolder) throws IOException {
        Path confFolder = new Path(instanceFolder, "conf");
        FileSystem fs = FileSystem.get(NutchConfiguration.create());
        fs.mkdirs(confFolder);
        copyConfigurationFiles(confFolder);
    }

    private static void copyConfigurationFiles(Path target) throws FileNotFoundException, IOException {
        FileSystem fs = FileSystem.get(NutchConfiguration.create());

        InputStream in = AdministrationApp.class.getResourceAsStream("/nutch-default.xml");
        OutputStream out = new FileOutputStream(
                new File(new File(target.makeQualified(fs).toUri()), "nutch-default.xml"));
        copyContent(in, out);

        in = AdministrationApp.class.getResourceAsStream("/nutch-site.xml");
        out = new FileOutputStream(new File(new File(target.makeQualified(fs).toUri()), "nutch-site.xml"));
        copyContent(in, out);
    }

    private static void copyContent(InputStream in, OutputStream out) throws IOException {
        byte[] buf = new byte[1024];
        int len;
        while ((len = in.read(buf)) > 0) {
            out.write(buf, 0, len);
        }
        out.flush();
        in.close();
        out.close();
    }

    /**
     * Push nutch-(default|site).xml from a given  folder/conf 
     * into a configuration. 
     * 
     * @param configuration
     * @param folder
     */
    private static void configure(Configuration configuration, Path folder) throws IOException {
        FileSystem fs = FileSystem.get(NutchConfiguration.create());
        Path confFolder = new Path(folder, "conf");

        if (fs.exists(confFolder)) {
            Path defaultConf = new Path(confFolder, "nutch-default.xml");
            if (fs.exists(defaultConf)) {
                configuration.addResource(defaultConf.makeQualified(fs));
            }

            Path siteConf = new Path(confFolder, "nutch-site.xml");
            if (fs.exists(siteConf)) {
                configuration.addResource(siteConf.makeQualified(fs));
            }
        }
    }
}