org.jclouds.azureblob.blobstore.strategy.AzureBlobBlockUploadStrategy.java Source code

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Here is the source code for org.jclouds.azureblob.blobstore.strategy.AzureBlobBlockUploadStrategy.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.jclouds.azureblob.blobstore.strategy;

import com.google.common.collect.Lists;
import com.google.common.hash.Hashing;
import com.google.common.io.BaseEncoding;
import com.google.inject.Inject;
import org.jclouds.azureblob.AzureBlobClient;
import org.jclouds.blobstore.domain.Blob;
import org.jclouds.blobstore.reference.BlobStoreConstants;
import org.jclouds.io.Payload;
import org.jclouds.io.PayloadSlicer;
import org.jclouds.logging.Logger;

import javax.annotation.Resource;
import javax.inject.Named;

import java.security.SecureRandom;
import java.util.List;

import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.base.Preconditions.checkState;

/**
 * Decomposes a blob into blocks for upload and assembly through PutBlock and PutBlockList
 */
public class AzureBlobBlockUploadStrategy implements MultipartUploadStrategy {
    @Resource
    @Named(BlobStoreConstants.BLOBSTORE_LOGGER)
    private Logger logger = Logger.NULL;

    private final AzureBlobClient client;
    private final PayloadSlicer slicer;

    @Inject
    public AzureBlobBlockUploadStrategy(AzureBlobClient client, PayloadSlicer slicer) {
        this.client = checkNotNull(client, "client");
        this.slicer = checkNotNull(slicer, "slicer");
    }

    @Override
    public String execute(String container, Blob blob) {
        String blobName = blob.getMetadata().getName();
        Payload payload = blob.getPayload();
        Long length = payload.getContentMetadata().getContentLength();
        checkNotNull(length,
                "please invoke payload.getContentMetadata().setContentLength(length) prior to azure block upload");
        checkArgument(length <= (MAX_NUMBER_OF_BLOCKS * MAX_BLOCK_SIZE));
        long offset = 0L;
        List<String> blockIds = Lists.newArrayList();
        int blockCount = 0;
        int totalBlocks = (int) Math.ceil(((double) length) / MAX_BLOCK_SIZE);
        long bytesWritten = 0;
        while (offset < length) {
            blockCount++;
            long chunkSize = MAX_BLOCK_SIZE;
            if (length - offset < MAX_BLOCK_SIZE) {
                chunkSize = length % MAX_BLOCK_SIZE;
            }
            bytesWritten += chunkSize;
            Payload block = slicer.slice(payload, offset, chunkSize);
            offset += MultipartUploadStrategy.MAX_BLOCK_SIZE;
            String blockName = blobName + "-" + offset + "-" + new SecureRandom().nextInt();
            byte blockIdBytes[] = Hashing.md5().hashBytes(blockName.getBytes()).asBytes();
            String blockId = BaseEncoding.base64().encode(blockIdBytes);
            blockIds.add(blockId);
            client.putBlock(container, blobName, blockId, block);
        }
        checkState(bytesWritten == length, "Wrote %s bytes, but we wanted to write %s bytes", bytesWritten, length);
        return client.putBlockList(container, blobName, blockIds);
    }
}