gobblin.data.management.trash.AsyncTrash.java Source code

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Here is the source code for gobblin.data.management.trash.AsyncTrash.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 gobblin.data.management.trash;

import gobblin.util.Decorator;
import gobblin.util.ExecutorsUtils;
import gobblin.util.executors.ScalingThreadPoolExecutor;

import java.io.Closeable;
import java.io.IOException;
import java.util.Properties;
import java.util.concurrent.Callable;
import java.util.concurrent.TimeUnit;

import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.security.UserGroupInformation;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.common.base.Optional;
import com.google.common.util.concurrent.ListenableFuture;
import com.google.common.util.concurrent.ListeningExecutorService;
import com.google.common.util.concurrent.MoreExecutors;

/**
 * Implementation of {@link Trash} that deletes files asynchronously and in parallel.
 *
 * <p>
 *   This implementation is not built through {@link TrashFactory} because coder must be aware that the trash
 *   implementation is asynchronous. However, internally it uses {@link TrashFactory} to instantiate the trash
 *   implementation that will actually perform the deletes. This class acts as a {@link Decorator} of the
 *   inner trash.
 * </p>
 *
 * <p>
 *   Trash methods will always return true, regardless of success of the actual trash operation. However, additional
 *   methods are provided to get a future for the operation.
 * </p>
 */
public class AsyncTrash implements GobblinProxiedTrash, Closeable, Decorator {

    public static final String MAX_DELETING_THREADS_KEY = "gobblin.trash.async.max.deleting.threads";
    public static final int DEFAULT_MAX_DELETING_THREADS = 100;

    private static final Logger LOGGER = LoggerFactory.getLogger(AsyncTrash.class);

    private final ProxiedTrash innerTrash;
    private final ListeningExecutorService executor;

    public AsyncTrash(FileSystem fs, Properties properties) throws IOException {
        this(fs, properties, UserGroupInformation.getCurrentUser().getShortUserName());
    }

    public AsyncTrash(FileSystem fs, Properties properties, String user) throws IOException {

        int maxDeletingThreads = DEFAULT_MAX_DELETING_THREADS;
        if (properties.containsKey(MAX_DELETING_THREADS_KEY)) {
            maxDeletingThreads = Integer.parseInt(properties.getProperty(MAX_DELETING_THREADS_KEY));
        }
        this.innerTrash = TrashFactory.createProxiedTrash(fs, properties, user);
        this.executor = ExecutorsUtils.loggingDecorator(MoreExecutors.getExitingExecutorService(
                ScalingThreadPoolExecutor.newScalingThreadPool(0, maxDeletingThreads, 100, ExecutorsUtils
                        .newThreadFactory(Optional.of(LOGGER), Optional.of("Async-trash-delete-pool-%d")))));
    }

    @Override
    public boolean moveToTrashAsUser(Path path, String user) throws IOException {
        moveToTrashAsUserFuture(path, user);
        return true;
    }

    /**
     * Schedules a {@link ProxiedTrash#moveToTrashAsUser} and returns a future for this operation.
     * @param path {@link Path} to delete.
     * @param user User to execute the operation as.
     * @return true if operation succeeded.
     */
    public ListenableFuture<Boolean> moveToTrashAsUserFuture(final Path path, final String user) {
        return this.executor.submit(new Callable<Boolean>() {
            @Override
            public Boolean call() throws IOException {
                return AsyncTrash.this.innerTrash.moveToTrashAsUser(path, user);
            }
        });
    }

    public boolean moveToTrashAsOwner(Path path) {
        moveToTrashAsOwnerFuture(path);
        return true;
    }

    /**
     * Schedules a {@link ProxiedTrash#moveToTrashAsOwner} and returns a future for this operation.
     * @param path {@link Path} to delete.
     * @return true if operation succeeded.
     */
    public ListenableFuture<Boolean> moveToTrashAsOwnerFuture(final Path path) {
        return this.executor.submit(new Callable<Boolean>() {
            @Override
            public Boolean call() throws IOException {
                return AsyncTrash.this.innerTrash.moveToTrashAsOwner(path);
            }
        });
    }

    @Override
    public boolean moveToTrash(Path path) throws IOException {
        moveToTrashFuture(path);
        return true;
    }

    /**
     * Schedules a {@link ProxiedTrash#moveToTrash} and returns a future for this operation.
     * @param path {@link Path} to delete.
     * @return true if operation succeeded.
     */
    public ListenableFuture<Boolean> moveToTrashFuture(final Path path) {
        return this.executor.submit(new Callable<Boolean>() {
            @Override
            public Boolean call() throws IOException {
                return AsyncTrash.this.innerTrash.moveToTrash(path);
            }
        });
    }

    @Override
    public Object getDecoratedObject() {
        return this.innerTrash;
    }

    @Override
    public void close() throws IOException {
        try {
            this.executor.shutdown();
            this.executor.awaitTermination(5, TimeUnit.HOURS);
        } catch (InterruptedException ie) {
            this.executor.shutdownNow();
        }
    }
}