从 Android 向 Azure Block Blob 添加一行文本

Question

我想从 Android 设备向现有的 Azure 云块 blob 附加一行文本。

在 VB.Net 中，我将 AcquireLease、getBlockBlobReference、DownloadToFile 添加到本地文件系统、UploadToFile、ReleaseLease 行。简单又安全，就是有点啰嗦。

在Android中，看起来有点棘手。目前，我最好的解决方案是：

                CloudBlockBlob blob1=container.getBlockBlobReference(chosenOne+".txt"); 

                String proposedLeaseId1 = UUID.randomUUID().toString(); 
                OperationContext operationContext1 = new OperationContext();
                blob1.acquireLease(15, proposedLeaseId1, null /*access condition*/,null/* BlobRequestOptions */, operationContext1);

                AccessCondition condition = new AccessCondition();
                condition.setLeaseID(proposedLeaseId1);

                BlobInputStream blobIn = blob1.openInputStream();

                blob1.downloadAttributes();
                long blobLengthToUse = blob1.getProperties().getLength();

                byte[] result = new byte[(int) blobLengthToUse];
                blob1.downloadToByteArray(result,0);

                blobIn.close();

                CloudBlockBlob blob1 = container.getBlockBlobReference(chosenOne+".txt");   

                String proposedLeaseId1 = UUID.randomUUID().toString(); 
                OperationContext operationContext1 = new OperationContext();
                blob1.acquireLease(15, proposedLeaseId1, null /*access condition*/,null/* BlobRequestOptions */, operationContext1);


                AccessCondition condition = new AccessCondition();
                condition.setLeaseID(proposedLeaseId1);

                BlobInputStream blobIn = blob1.openInputStream();

                blob1.downloadAttributes();
                long blobLengthToUse = blob1.getProperties().getLength();
                byte[] result = new byte[(int) blobLengthToUse];
                blob1.downloadToByteArray(result,0);

                blobIn.close();

                blob1.deleteIfExists(DeleteSnapshotsOption.NONE,condition, null, operationContext1);

                BlobOutputStream blobOut = blob1.openOutputStream(); 

                //this is a byte by byte write ...
                //which is fine ... but no use if you want to replace ...
                /*int next = blobIn.read();
                while (next != -1) {
                      blobOut.write(next);
                      next = blobIn.read();
                }*/

                blobOut.write(result);

                String strTemp="This is just a test string";

                blobOut.write(strTemp.getBytes());

                blobOut.close();

除了啰嗦之外，我担心一旦删除 blob，租约就会消失，我可能会遇到完整性问题。对于使此代码更简单和更安全的任何帮助，我将不胜感激。我知道 Microsoft 计划在 2015 年第 3 季度推出附加 blob，但我现在想实施它。

Answer 1

您可以调用PutBlock上传追加内容（每个块的最大大小为4MB，所以如果需要请将追加内容拆分成块），然后通过传入之前提交的块在这个blob上调用PutBlockList加上和新附加的块。

从 Android 向 Azure Block Blob 添加一行文本

Append line of text to Azure Block Blob from Android

android

azure-blob-storage