[Azure Storage]使用Java上传文件到Storage并生成SAS签名

Azure官网提供了比较详细的文档，您可以参考：https://azure.microsoft.com/en-us/documentation/articles/storage-java-how-to-use-blob-storage/#download-a-blob

或者，请参考下面的步骤：

1. 下载Azure SDK for Java，地址为：https://azure.microsoft.com/en-us/documentation/articles/java-download-azure-sdk/
2. 将Azure SDK for Java的jar包导入到项目中
3. 参考本文最后附加的代码

代码说明如下：

• 本人不是Java方面的专家，因而代码的规范性上或许不如你专业，你可以酌情调整。此外，代码仅作测试用，请勿用于生产环境
• 测试附件中的代码的时候，需要在代码中替换你的：存储帐号名称、存储帐号密钥、容器名称、视频路径，如下图所示：

• 附加的代码中，提供了两个方法，UploadSmallSize和UploadLargeSize用于视频是上传。对于大文件（超过100M），需要先将文件分片而后上传。这种情况下，请使用UploadLargeSize。
• GetBlobUrl – 这个方法是用于返回Blob的URL。由于Blob在默认情况下无法直接通过URL访问，我们在这个方法中为Blob添加了SAS签名对Blob设置了权限，使得在一定时间范围内是可以访问的。关于SAS的更多内容，您可以参考：https://azure.microsoft.com/en-us/documentation/articles/storage-dotnet-shared-access-signature-part-2/

import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.net.URISyntaxException;
import java.security.InvalidKeyException;
import java.security.KeyManagementException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.security.cert.X509Certificate;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Date;
import java.util.EnumSet;
import java.util.GregorianCalendar;
import java.util.Random;
import java.util.TimeZone;

import javax.net.ssl.*;

import com.microsoft.azure.storage.CloudStorageAccount;
import com.microsoft.azure.storage.StorageCredentials;
import com.microsoft.azure.storage.StorageCredentialsAccountAndKey;
import com.microsoft.azure.storage.StorageException;
import com.microsoft.azure.storage.blob.BlobContainerPermissions;
import com.microsoft.azure.storage.blob.BlobContainerPublicAccessType;
import com.microsoft.azure.storage.blob.BlockEntry;
import com.microsoft.azure.storage.blob.BlockSearchMode;
import com.microsoft.azure.storage.blob.CloudBlobClient;
import com.microsoft.azure.storage.blob.CloudBlobContainer;
import com.microsoft.azure.storage.blob.CloudBlockBlob;
import com.microsoft.azure.storage.blob.SharedAccessBlobPermissions;
import com.microsoft.azure.storage.blob.SharedAccessBlobPolicy;


public class JavaStorageClient {

    static final String storageAccountName = "<Storage Account>";
    static final String storageAccountKey = "<Storage Key>";
    static final String containerName = "<Container Name>";
    static final String videoPath = "<>";
    //static final String videoPath = "D:\Training\all hands meeting-1.mp4";
    
    static CloudStorageAccount storageAccount = null;
    
    private static void Init() throws InvalidKeyException, URISyntaxException, NoSuchAlgorithmException, KeyManagementException{
        TrustManager[] trustAllCerts = new TrustManager[]{new X509TrustManager(){public X509Certificate[] getAcceptedIssuers(){return null;}
        public void checkClientTrusted(X509Certificate[] certs, String authType){}
        public void checkServerTrusted(X509Certificate[] certs, String authType){}}};
        SSLContext sc = SSLContext.getInstance("TLS");
        sc.init(null, trustAllCerts, new SecureRandom());
        HttpsURLConnection.setDefaultSSLSocketFactory(sc.getSocketFactory());

        
        StorageCredentials credentials = new StorageCredentialsAccountAndKey(storageAccountName, storageAccountKey);
        String connectionString = String.format("DefaultEndpointsProtocol=https;AccountName=%s;AccountKey=%s;EndpointSuffix=core.Chinacloudapi.cn", storageAccountName, storageAccountKey);
        storageAccount = CloudStorageAccount.parse(connectionString);
        
    }
    
    private static CloudBlobContainer GetContainer() throws URISyntaxException, StorageException{
        CloudBlobClient blobClient = storageAccount.createCloudBlobClient();
        CloudBlobContainer container;
        container = blobClient.getContainerReference(containerName);
        container.createIfNotExists();
        
        return container;
    }
    
    // For small size video, we can use this method.
    private static void UploadSmallSize() throws URISyntaxException, StorageException, FileNotFoundException, IOException, InvalidKeyException{
        System.out.println("===============Begin Uploading===============");
        File source  = new File(videoPath);
        String blobName = source.getName();
        CloudBlobContainer container = GetContainer();
        CloudBlockBlob blob = container.getBlockBlobReference(source .getName());
        
        blob.upload(new FileInputStream(source), source.length());
        System.out.println("===============Uploading Done===============");
        System.out.println("Blob URL: " + GetBlobUrl(container, blobName));
    }
    
    
    private static void UploadLargeSize() throws URISyntaxException, StorageException, IOException, InvalidKeyException{
        File source  = new File(videoPath);
        String blobName = source.getName();
        FileInputStream inputStream = new FileInputStream(source);
        final int blockLength = 1 * 1024*1024;
        byte[] bufferBytes = new byte[blockLength];
        int blockCount = (int)(source.length() / blockLength) + 1;
        System.out.println("Total block count："+blockCount+", Total size: "+source.length());
        int currentBlockSize = 0;
        
        CloudBlobContainer container = GetContainer();
        CloudBlockBlob blockBlobRef  = container.getBlockBlobReference(blobName);
        
        System.out.println("===============Begin Uploading===============");
        ArrayList<BlockEntry> blockList = new ArrayList<BlockEntry>();
        
        for (int i = 0; i < blockCount; i++) {
            //String blockID="OWM3MDhiMWEtODdhNS00YjE5LWE2NmEtYzAzMGJmZWIyYzli";//String.format("%09d", i);
            //blockID=getBASE64(blockID);//Base64.encode(blockID.getBytes());
            //String blockID="b"+String.valueOf(id);
            //String blockID =Base64.encode(sid.getBytes());
            //String.format("%08d", String.valueOf(10000+i));//String.valueOf(1000000+i);// Base64.encode(String.valueOf(1000000+i).getBytes());
           String blockID = String.format("%08d", i);
           currentBlockSize = blockLength;
           if (i == blockCount - 1){
               currentBlockSize = (int) (source.length() - blockLength * i);
               bufferBytes = new byte[currentBlockSize];
               }
           
           inputStream.read(bufferBytes, 0, currentBlockSize);
           blockBlobRef.uploadBlock(blockID, getRandomDataStream(blockLength), blockLength, null, null, null);
           blockList.add(new BlockEntry(blockID, BlockSearchMode.LATEST));
           System.out.println("Submitted block index：" + i + ", BlockIndex:" + blockID);
         }
         blockBlobRef.commitBlockList(blockList);
         System.out.println("===============Uploading Done===============");
         
         
         System.out.println("Blob URL: " + GetBlobUrl(container, blobName));
    }
    
    private static byte[] getRandomBuffer(int length) { 
        final Random randGenerator = new Random(); 
        final byte[] buff = new byte[length]; 
        randGenerator.nextBytes(buff); 
       return buff; 
    } 


    private static ByteArrayInputStream getRandomDataStream(int length) { 
        return new ByteArrayInputStream(getRandomBuffer(length)); 
    } 

    private static String GetBlobUrl(CloudBlobContainer container, String blobName) throws StorageException, InvalidKeyException, URISyntaxException{
        SharedAccessBlobPolicy policy = new SharedAccessBlobPolicy();
        GregorianCalendar calendar = new GregorianCalendar(TimeZone.getTimeZone("UTC"));
        calendar.setTime(new Date());
        
        // Immediately applicable
        policy.setSharedAccessStartTime(calendar.getTime());
        
        // Applicable time span is 1 hour
        calendar.add(Calendar.HOUR, 1);
        policy.setSharedAccessExpiryTime(calendar.getTime());
        
         // SAS grants READ access privileges
        policy.setPermissions(EnumSet.of(SharedAccessBlobPermissions.READ));
        BlobContainerPermissions containerPermissions = new BlobContainerPermissions();
        
        // Private blob-container with no access for anonymous users
        containerPermissions.setPublicAccess(BlobContainerPublicAccessType.OFF);
        container.uploadPermissions(containerPermissions);
        String sas = container.generateSharedAccessSignature(policy,null);
        
        CloudBlockBlob blob = container.getBlockBlobReference(blobName);
        String blobUri = blob.getUri().toString();
        
        return blobUri + "?"+ sas;
    }
    
    public static void main(String[] args) throws FileNotFoundException, URISyntaxException, StorageException, IOException, InvalidKeyException, KeyManagementException, NoSuchAlgorithmException {
        // TODO Auto-generated method stub
        Init();
        //UploadLargeSize();
        UploadSmallSize();
    }

}