org.apache.accumulo.master.tableOps.create.ChooseDir.java Source code

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Here is the source code for org.apache.accumulo.master.tableOps.create.ChooseDir.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.accumulo.master.tableOps.create;

import java.io.IOException;
import java.util.SortedSet;
import java.util.TreeSet;

import org.apache.accumulo.core.Constants;
import org.apache.accumulo.fate.Repo;
import org.apache.accumulo.master.Master;
import org.apache.accumulo.master.tableOps.MasterRepo;
import org.apache.accumulo.master.tableOps.TableInfo;
import org.apache.accumulo.master.tableOps.Utils;
import org.apache.accumulo.server.ServerConstants;
import org.apache.accumulo.server.fs.VolumeChooserEnvironment;
import org.apache.accumulo.server.fs.VolumeChooserEnvironmentImpl;
import org.apache.accumulo.server.fs.VolumeManager;
import org.apache.accumulo.server.tablets.UniqueNameAllocator;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.io.Text;

class ChooseDir extends MasterRepo {
    private static final long serialVersionUID = 1L;

    private final TableInfo tableInfo;

    ChooseDir(TableInfo ti) {
        this.tableInfo = ti;
    }

    @Override
    public long isReady(long tid, Master environment) {
        return 0;
    }

    @Override
    public Repo<Master> call(long tid, Master master) throws Exception {
        // Constants.DEFAULT_TABLET_LOCATION has a leading slash prepended to it so we don't need to add
        // one here

        VolumeChooserEnvironment chooserEnv = new VolumeChooserEnvironmentImpl(tableInfo.getTableId(), null,
                master.getContext());

        String baseDir = master.getFileSystem().choose(chooserEnv, ServerConstants.getBaseUris(master.getContext()))
                + Constants.HDFS_TABLES_DIR + Path.SEPARATOR + tableInfo.getTableId();
        tableInfo.defaultTabletDir = baseDir + Constants.DEFAULT_TABLET_LOCATION;

        if (tableInfo.getInitialSplitSize() > 0) {
            createTableDirectoriesInfo(master, baseDir);
        }
        return new CreateDir(tableInfo);
    }

    @Override
    public void undo(long tid, Master master) throws Exception {
        VolumeManager fs = master.getFileSystem();
        fs.deleteRecursively(new Path(tableInfo.getSplitDirsFile()));
    }

    /**
     * Create unique table directory names that will be associated with split values. Then write these
     * to the file system for later use during this FATE operation.
     */
    private void createTableDirectoriesInfo(Master master, String baseDir) throws IOException {
        SortedSet<Text> splits = Utils.getSortedSetFromFile(master.getInputStream(tableInfo.getSplitFile()), true);
        SortedSet<Text> tabletDirectoryInfo = createTabletDirectoriesSet(master, splits.size(), baseDir);
        writeTabletDirectoriesToFileSystem(master, tabletDirectoryInfo);
    }

    /**
     * Create a set of unique table directories. These will be associated with splits in a follow-on
     * FATE step.
     */
    private SortedSet<Text> createTabletDirectoriesSet(Master master, int num, String baseDir) {
        String tabletDir;
        UniqueNameAllocator namer = master.getContext().getUniqueNameAllocator();
        SortedSet<Text> splitDirs = new TreeSet<>();
        for (int i = 0; i < num; i++) {
            tabletDir = "/" + Constants.GENERATED_TABLET_DIRECTORY_PREFIX + namer.getNextName();
            splitDirs.add(new Text(baseDir + "/" + new Path(tabletDir).getName()));
        }
        return splitDirs;
    }

    /**
     * Write the SortedSet of Tablet Directory names to the file system for use in the next phase of
     * the FATE operation.
     */
    private void writeTabletDirectoriesToFileSystem(Master master, SortedSet<Text> dirs) throws IOException {
        FileSystem fs = master.getFileSystem().getDefaultVolume().getFileSystem();
        if (fs.exists(new Path(tableInfo.getSplitDirsFile())))
            fs.delete(new Path(tableInfo.getSplitDirsFile()), true);
        try (FSDataOutputStream stream = master.getOutputStream(tableInfo.getSplitDirsFile())) {
            for (Text dir : dirs)
                stream.writeBytes(dir + "\n");
        }
    }

}