問題描述

查看Java Storage SDK，想找一個 uploadWithResponse 的示例代碼，但是通過全網(wǎng)搜索，結(jié)果沒有任何有幫助的代碼。使用最近ChatGPT來尋求答案，得到非常有格式的內(nèi)容：

| 問：java azure storage account to use uploadWithResponse |
答：To use the uploadWithResponse method with the Azure Blob Storage client library for Java, follow these steps:

1. Add the Azure Storage Blob dependency to your project's build file. For Maven, add the following to your pom.xml:

<dependency>
  <groupId>com.azure</groupId>
  <artifactId>azure-storage-blob</artifactId>
  <version>12.14.2</version>
</dependency>

2. Import the necessary classes:

import com.azure.storage.blob.BlobClient; 
import com.azure.storage.blob.BlobContainerClient; 
import com.azure.storage.blob.BlobServiceClient; 
import com.azure.storage.blob.BlobServiceClientBuilder;

3. Create a BlobServiceClient instance using your storage account connection string:

String connectionString = "your_connection_string";
BlobServiceClient blobServiceClient = new BlobServiceClientBuilder().connectionString(connectionString).buildClient();

4. Get a reference to the container and the blob you want to upload:

String containerName = "your_container_name";
String blobName = "your_blob_name";
BlobContainerClient containerClient = blobServiceClient.getBlobContainerClient(containerName);
BlobClient blobClient = containerClient.getBlobClient(blobName);

5. Upload a file using the uploadWithResponse method:

import com.azure.storage.blob.models.BlobUploadFromFileOptions; 
import java.nio.file.Path; 
import java.nio.file.Paths;

Path filePath = Paths.get("path/to/your/file");
BlobUploadFromFileOptions options = new BlobUploadFromFileOptions(filePath);
blobClient.uploadWithResponse(options, null, null);

This will upload the file to the specified blob in the Azure Blob Storage container. Remember to replace the placeholders with your actual connection string, container name, blob name, and file path.

繼續(xù)追問：BlobParallelUploadOptions with string content

答：(前面4步的答案一樣，第五步的內(nèi)容為)

5. Convert the string content to an InputStream and set up BlobParallelUploadOptions:

String content = "your_string_content";
InputStream inputStream = new ByteArrayInputStream(content.getBytes(StandardCharsets.UTF_8)); 
long blockSize = 100 * 1024L; // 100 KB
int maxConcurrency = 5;
ParallelTransferOptions parallelTransferOptions = new ParallelTransferOptions(blockSize, maxConcurrency);
BlobParallelUploadOptions options = new BlobParallelUploadOptions(inputStream).setParallelTra 

*在繼續(xù)問：如何使用 “To avoid overwriting, pass "" to setIfNoneMatch(String ifNoneMatch). how to use the setifnonematch” **
| 答：(前面4步的答案一樣，第五步的內(nèi)容為)

5. Set up BlobUploadOptions with setIfNoneMatch:

BlobUploadOptions options = new BlobUploadOptions()
    .setInputStream(inputStream)
    .setLength((long) content.length())
    .setHttpHeaders(new BlobHttpHeaders().setContentType("text/plain"))
    .setRequestConditions(new BlobRequestConditions().setIfNoneMatch("*"));

6. Upload the string content using the uploadWithResponse method with BlobUploadOptions:

blobClient.uploadWithResponse(options, null, null);

This will upload the string content to the specified blob in the Azure Blob Storage container only if the blob does not already exist. If the blob exists, the upload will fail with a BlobStorageException due to the setIfNoneMatch("*") condition. Remember to replace the placeholders with your actual connection string, container name, blob name, and string content.

問題解答

根據(jù)ChatGPT提供的三部分信息，通過人力拼接和測試。得到了成功執(zhí)行的uploadWithResponse代碼：

uploadWithResponse示例代碼

            String storageConnectionString = "DefaultEndpointsProtocol=https;AccountName=***************";
      　　　　　　String containerName = "******************";
　　　　　　      String fileName = "******************";

                BlobServiceClient blobServiceClient = new BlobServiceClientBuilder()
                                .connectionString(storageConnectionString)
                                .buildClient();
                BlobContainerClient containerClient = blobServiceClient.createBlobContainer(containerName);
                BlobClient blobClient = containerClient.getBlobClient(fileName);

                //準備content并且初始化blob parallel upload options對象
 　             String content = "Test to append new content into exists blob! by blogs lu bian liang zhan deng ";
                InputStream inputStream = new ByteArrayInputStream(content.getBytes(StandardCharsets.UTF_8));
                BlobParallelUploadOptions options = new BlobParallelUploadOptions(inputStream, content.getBytes().length);
                options.setRequestConditions(new BlobRequestConditions().setIfNoneMatch("*"));
                Response<BlockBlobItem> rsp = blobClient.uploadWithResponse(options, null, null); if(rsp.getStatusCode()==201)
                {
                        System.out.println("append content successful........");                        
                }

說明：

1） content 中為需要寫入Blob的內(nèi)容

2） 把string轉(zhuǎn)換為以UTF_8編碼的input stream

3） 根據(jù) input stream來初始化 blob paralle upload options對象

4） 設(shè)置 Request Conditions，當(dāng)不需要重寫的時候，可以使用 setIfNoneMatch("*")。如果操作的文件存在，則會出現(xiàn) Status code 409, BlobAlreadyExistss 提示。

5） 調(diào)用upload with response方法，獲取返回值，如果 返回值得status code為 201，表示Storage Account接受了這次 blob 內(nèi)容的改動。

運行效果展示圖

blob upload with response.gif

參考資料

BlobClient Class：https://learn.microsoft.com/en-us/java/api/com.azure.storage.blob.BlobClient?view=azure-java-stable

BlobRequestConditions Class：https://learn.microsoft.com/en-us/java/api/com.azure.storage.blob.models.blobrequestconditions?view=azure-java-stable#com-azure-storage-blob-models-blobrequestconditions-setifnonematch(java-lang-string)

適用于 Java 的 Azure Blob 存儲客戶端庫 : https://docs.azure.cn/zh-cn/storage/blobs/storage-quickstart-blobs-java?tabs=powershell%2Cmanaged-identity%2Croles-azure-portal%2Csign-in-azure-cli#upload-blobs-to-a-container

當(dāng)在復(fù)雜的環(huán)境中面臨問題，格物之道需：濁而靜之徐清，安以動之徐生。 云中，恰是如此!