alluxio.underfs.wasb.WasbUnderFileSystem.java Source code

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Here is the source code for alluxio.underfs.wasb.WasbUnderFileSystem.java

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/*
 * The Alluxio Open Foundation licenses this work under the Apache License, version 2.0
 * (the "License"). You may not use this work except in compliance with the License, which is
 * available at www.apache.org/licenses/LICENSE-2.0
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied, as more fully set forth in the License.
 *
 * See the NOTICE file distributed with this work for information regarding copyright ownership.
 */

package alluxio.underfs.wasb;

import alluxio.AlluxioURI;
import alluxio.conf.PropertyKey;
import alluxio.underfs.UnderFileSystem;
import alluxio.underfs.UnderFileSystemConfiguration;
import alluxio.underfs.hdfs.HdfsUnderFileSystem;
import alluxio.underfs.options.FileLocationOptions;

import org.apache.hadoop.conf.Configuration;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;
import java.util.List;
import java.util.Map;

import javax.annotation.concurrent.ThreadSafe;

/**
 * An {@link UnderFileSystem} uses the Microsoft Azure Blob Storage.
 */
@ThreadSafe
public class WasbUnderFileSystem extends HdfsUnderFileSystem {
    private static final Logger LOG = LoggerFactory.getLogger(WasbUnderFileSystem.class);

    /** Constant for the wasb URI scheme. */
    public static final String SCHEME = "wasb://";

    /**
     * Prepares the configuration for this Wasb as an HDFS configuration.
     *
     * @param conf the configuration for this UFS
     * @return the created configuration
     */
    public static Configuration createConfiguration(UnderFileSystemConfiguration conf) {
        Configuration wasbConf = HdfsUnderFileSystem.createConfiguration(conf);
        for (Map.Entry<String, String> entry : conf.toMap().entrySet()) {
            String key = entry.getKey();
            String value = entry.getValue();
            if (PropertyKey.Template.UNDERFS_AZURE_ACCOUNT_KEY.matches(key)) {
                wasbConf.set(key, value);
            }
        }
        wasbConf.set("fs.AbstractFileSystem.wasb.impl", "org.apache.hadoop.fs.azure.Wasb");
        wasbConf.set("fs.wasb.impl", "org.apache.hadoop.fs.azure.NativeAzureFileSystem");
        return wasbConf;
    }

    /**
     * Factory method to construct a new Wasb {@link UnderFileSystem}.
     *
     * @param uri the {@link AlluxioURI} for this UFS
     * @param conf the configuration for this UFS
     * @return a new Wasb {@link UnderFileSystem} instance
     */
    public static WasbUnderFileSystem createInstance(AlluxioURI uri, UnderFileSystemConfiguration conf) {
        Configuration wasbConf = createConfiguration(conf);
        return new WasbUnderFileSystem(uri, conf, wasbConf);
    }

    /**
     * Constructs a new Wasb {@link UnderFileSystem}.
     *
     * @param ufsUri the {@link AlluxioURI} for this UFS
     * @param conf the configuration for this UFS
     * @param wasbConf the configuration for this Wasb UFS
     */
    public WasbUnderFileSystem(AlluxioURI ufsUri, UnderFileSystemConfiguration conf, final Configuration wasbConf) {
        super(ufsUri, conf, wasbConf);
    }

    @Override
    public String getUnderFSType() {
        return "wasb";
    }

    @Override
    public long getBlockSizeByte(String path) throws IOException {
        // wasb is an object store, so use the default block size, like other object stores.
        return mUfsConf.getBytes(PropertyKey.USER_BLOCK_SIZE_BYTES_DEFAULT);
    }

    // Not supported
    @Override
    public List<String> getFileLocations(String path) throws IOException {
        LOG.debug("getFileLocations is not supported when using WasbUnderFileSystem.");
        return null;
    }

    // Not supported
    @Override
    public List<String> getFileLocations(String path, FileLocationOptions options) throws IOException {
        LOG.debug("getFileLocations is not supported when using WasbUnderFileSystem.");
        return null;
    }
}