Object的分块上传
更新时间：2022-10-21
分块上传的场景
除了通过putObject()方法上传文件到BOS以外，BOS还提供了另外一种上传模式：分块上传（Multipart Upload）。用户可以在如下的应用场景内（但不仅限于此），使用分块上传模式，如：
- 需要支持断点上传。
- 上传超过5GB大小的文件。
- 网络条件较差，和BOS的服务器之间的连接经常断开。
- 需要流式地上传文件。
- 上传文件之前，无法确定上传文件的大小。
Multipart Upload分块上传流程
假设有一个文件，本地路径为 /path/to/file.zip ，由于文件比较大，使用分块上传其传输到BOS中。
基本流程：
- 初始化Multipart Upload。
- 上传分块。
- 完成分块上传。
初始化Multipart Upload
使用 initiateMultipartUpload 方法来初始化一个分块上传事件：
示例代码：
// 开始Multipart Upload
InitiateMultipartUploadRequest initiateMultipartUploadRequest =
new InitiateMultipartUploadRequest(<BucketName>, <ObjectKey>);
InitiateMultipartUploadResponse initiateMultipartUploadResponse =
client.initiateMultipartUpload(initiateMultipartUploadRequest);
// 打印UploadId
System.out.println("UploadId: " + initiateMultipartUploadResponse.getUploadId());说明：
initiateMultipartUpload的返回结果中含有UploadId，它是区分分块上传事件的唯一标识，在后面的操作中，我们将用到它。
上传分块
将文件分块上传。
示例代码：
// 设置每块为 5MB
final long partSize = 1024 * 1024 * 5L;
File partFile = new File("/path/to/file.zip");
// 计算分块数目
int partCount = (int) (partFile.length() / partSize);
if (partFile.length() % partSize != 0) {
partCount++;
}
// 新建一个List保存每个分块上传后的ETag和PartNumber
List<PartETag> partETags = new ArrayList<PartETag>();
// 获取文件流
FileInputStream fis = new FileInputStream(partFile);
for (int i = 0; i < partCount; i++) {
// 计算每个分块的大小
long skipBytes = partSize * i;
long size = partSize < partFile.length() - skipBytes ?
partSize : partFile.length() - skipBytes;
byte[] buf = new byte[(int)size];
int offset = 0;
while (true) {
int byteRead = fis.read(buf, offset, (int)size);
offset += byteRead;
if (byteRead < 0 || offset >= size) {
break;
}
}
ByteArrayInputStream bufStream = new ByteArrayInputStream(buf);
// 创建UploadPartRequest，上传分块
UploadPartRequest uploadPartRequest = new UploadPartRequest();
uploadPartRequest.setBucketName(bucketName);
uploadPartRequest.setKey(objectkey);
uploadPartRequest.setUploadId(initiateMultipartUploadResponse.getUploadId());
uploadPartRequest.setInputStream(bufStream);
uploadPartRequest.setPartSize(size);
uploadPartRequest.setPartNumber(i + 1);
// 上传进度回调
uploadPartRequest.setProgressCallback(new BosProgressCallback<UploadPartRequest>() {
@Override
public void onProgress(UploadPartRequest request, long currentSize, long totalSize) {
Log.e(currentSize + "", totalSize + "");
}
});
UploadPartResponse uploadPartResponse = client.uploadPart(uploadPartRequest);
// 将返回的PartETag保存到List中。
partETags.add(uploadPartResponse.getPartETag());
System.out.println(uploadPartResponse.getPartETag());
}
// 关闭文件
fis.close();注意：上面代码的核心是调用
UploadPart方法来上传每一个分块，但是要注意以下几点：
- UploadPart 方法要求Part大小是1MB的整数倍或大于5MB。但是Upload Part接口并不会立即校验上传Part的大小；只有当Complete Multipart Upload的时候才会校验。
- 为了保证数据在网络传输过程中不出现错误，建议您在
UploadPart后，使用每个分块BOS返回的Content-MD5值分别验证已上传分块数据的正确性。当所有分块数据合成一个Object后，不再含MD5值。- Part号码的范围是1~10000。如果超出这个范围，BOS将返回InvalidArgument的错误码。
- 每次上传Part时都要把流定位到此次上传块开头所对应的位置。
- 每次上传Part之后，BOS的返回结果会包含一个
PartETag对象，它是上传块的ETag与块编号（PartNumber）的组合，在后续完成分块上传的步骤中会用到它，因此需要将其保存起来。一般来讲这些PartETag对象将被保存到List中。- 进度回调接口的使用可以参考“获取上传进度”一章。
完成分块上传
示例代码
CompleteMultipartUploadRequest completeMultipartUploadRequest =
new CompleteMultipartUploadRequest(<BucketName>, <ObjectKey>,
initiateMultipartUploadResponse.getUploadId(), partETags);
// 完成分块上传
CompleteMultipartUploadResponse completeMultipartUploadResponse =
client.completeMultipartUpload(completeMultipartUploadRequest);
// 打印Object的ETag
System.out.println(completeMultipartUploadResponse.getETag());说明：上面代码中的
partETags是第二步中保存的partETag的列表，BOS收到用户提交的Part列表后，会逐一验证每个数据Part的有效性。当所有的数据Part验证通过后，BOS将把这些数据part组合成一个完整的Object。
完整示例
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import org.json.JSONException;
import android.app.Activity;
import android.os.Bundle;
import com.baidubce.BceClientException;
import com.baidubce.BceServiceException;
import com.baidubce.auth.DefaultBceCredentials;
import com.baidubce.demo.R;
import com.baidubce.services.bos.BosClient;
import com.baidubce.services.bos.BosClientConfiguration;
import com.baidubce.services.bos.model.CompleteMultipartUploadRequest;
import com.baidubce.services.bos.model.CompleteMultipartUploadResponse;
import com.baidubce.services.bos.model.InitiateMultipartUploadRequest;
import com.baidubce.services.bos.model.InitiateMultipartUploadResponse;
import com.baidubce.services.bos.model.PartETag;
import com.baidubce.services.bos.model.UploadPartRequest;
import com.baidubce.services.bos.model.UploadPartResponse;
public class ExampleActivity extends Activity {
private String bucketName = <BucketName>;
private String objectKey = <ObjectKey>;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
new Thread(new Runnable() {
@Override
public void run() {
try {
BosClientConfiguration config = new BosClientConfiguration();
config.setCredentials(new DefaultBceCredentials(<AccessKeyID>, <SecretAccessKey>));
config.setEndpoint(<EndPoint>);
BosClient client = new BosClient(config);
// 开始Multipart Upload
InitiateMultipartUploadRequest initiateMultipartUploadRequest = new InitiateMultipartUploadRequest(<BucketName>, <ObjectKey>);
InitiateMultipartUploadResponse initiateMultipartUploadResponse =
client.initiateMultipartUpload(initiateMultipartUploadRequest);
// 打印UploadId
System.out.println("UploadId: " + initiateMultipartUploadResponse.getUploadId());
// 设置每块为 5MB
final long partSize = 1024 * 1024 * 5L;
File partFile = new File("/path/to/file.zip");
// 计算分块数目
int partCount = (int) (partFile.length() / partSize);
if (partFile.length() % partSize != 0) {
partCount++;
}
// 新建一个List保存每个分块上传后的ETag和PartNumber
List<PartETag> partETags = new ArrayList<PartETag>();
// 获取文件流
FileInputStream fis = new FileInputStream(partFile);
for (int i = 0; i < partCount; i++) {
// 计算每个分块的大小
long skipBytes = partSize * i;
long size = partSize < partFile.length() - skipBytes ?
partSize : partFile.length() - skipBytes;
byte[] buf = new byte[(int)size];
int offset = 0;
while (true) {
int byteRead = fis.read(buf, offset, (int)size);
offset += byteRead;
if (byteRead < 0 || offset >= size) {
break;
}
}
ByteArrayInputStream bufStream = new ByteArrayInputStream(buf);
// 创建UploadPartRequest，上传分块
UploadPartRequest uploadPartRequest = new UploadPartRequest();
uploadPartRequest.setBucketName(<BucketName>);
uploadPartRequest.setKey(<ObjectKey>);
uploadPartRequest.setUploadId(initiateMultipartUploadResponse.getUploadId());
uploadPartRequest.setInputStream(fis);
uploadPartRequest.setPartSize(size);
uploadPartRequest.setPartNumber(i + 1);
UploadPartResponse uploadPartResponse = client.uploadPart(uploadPartRequest);
// 将返回的PartETag保存到List中。
partETags.add(uploadPartResponse.getPartETag());
System.out.println(uploadPartResponse.getPartETag());
}
// 关闭文件
fis.close();
CompleteMultipartUploadRequest completeMultipartUploadRequest = new CompleteMultipartUploadRequest(<BucketName>, <ObjectKey>, initiateMultipartUploadResponse.getUploadId(), partETags);
// 完成分块上传
CompleteMultipartUploadResponse completeMultipartUploadResponse =
client.completeMultipartUpload(completeMultipartUploadRequest);
// 打印Object的ETag
System.out.println(completeMultipartUploadResponse.getETag());
} catch (BceServiceException e) {
System.out.println("Error ErrorCode: " + e.getErrorCode());
System.out.println("Error RequestId: " + e.getRequestId());
System.out.println("Error StatusCode: " + e.getStatusCode());
System.out.println("Error Message: " + e.getMessage());
System.out.println("Error ErrorType: " + e.getErrorType());
} catch (BceClientException e) {
System.out.println("Error Message: " + e.getMessage());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}).start();
}}取消分块上传
用户可以使用abortMultipartUpload方法取消分块上传。
示例代码：
AbortMultipartUploadRequest abortMultipartUploadRequest =
new AbortMultipartUploadRequest(<BucketName>, <ObjectKey>, <UploadId>);
// 取消分块上传
client.abortMultipartUpload(abortMultipartUploadRequest);获取未完成的分块上传
用户可以使用 listMultipartUploads 方法获取Bucket内未完成的分块上传事件。
基本流程
- 创建listMultipartUploadsRequest类的实例,传入
<BucketName>参数。 - 创建BOSClient类的实例,执行BOSClient.listMultipartUploads( )方法。
- listMultipartUploads()返回所有已上传part的信息。
示例代码
ListMultipartUploadsRequest listMultipartUploadsRequest =
new ListMultipartUploadsRequest(<BucketName>);
// 获取Bucket内所有上传事件
ListMultipartUploadsResponse list = client.listMultipartUploads(listMultipartUploadsRequest);
// 遍历所有上传事件
for (MultipartUploadSummary multipartUpload : list.getMultipartUploads()) {
System.out.println("Key: " + multipartUpload.getKey() + " UploadId: " + multipartUpload.getUploadId());
}注意：
- 默认情况下，如果Bucket中的分块上传事件的数目大于1000，则只会返回1000个Object，并且返回结果中IsTruncated的值为True，同时返回NextKeyMarker作为下次读取的起点。
- 若想获取更多分块上传事件，可以使用KeyMarker参数分次读取。
完整示例
import android.app.Activity;
import android.os.Bundle;
import com.baidubce.BceClientException;
import com.baidubce.BceServiceException;
import com.baidubce.auth.DefaultBceCredentials;
import com.baidubce.demo.R;
import com.baidubce.services.bos.BosClient;
import com.baidubce.services.bos.BosClientConfiguration;
import com.baidubce.services.bos.model.ListMultipartUploadsRequest;
import com.baidubce.services.bos.model.ListMultipartUploadsResponse;
import com.baidubce.services.bos.model.MultipartUploadSummary;
public class ExampleActivity extends Activity {
private String bucketName = <BucketName>;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
new Thread(new Runnable() {
@Override
public void run() {
try {
BosClientConfiguration config = new BosClientConfiguration();
config.setCredentials(new DefaultBceCredentials(<AccessKeyID>, <SecretAccessKey>));
config.setEndpoint(<EndPoint>);
BosClient client = new BosClient(config);
ListMultipartUploadsRequest listMultipartUploadsRequest =
new ListMultipartUploadsRequest(<BucketName>);
// 获取Bucket内所有上传事件
ListMultipartUploadsResponse listing = client.listMultipartUploads(listMultipartUploadsRequest);
// 遍历所有上传事件
for (MultipartUploadSummary multipartUpload : listing.getMultipartUploads()) {
System.out.println("Key: " + multipartUpload.getKey() + " UploadId: " + multipartUpload.getUploadId());
}
} catch (BceServiceException e) {
System.out.println("Error ErrorCode: " + e.getErrorCode());
System.out.println("Error RequestId: " + e.getRequestId());
System.out.println("Error StatusCode: " + e.getStatusCode());
System.out.println("Error ErrorType: " + e.getErrorType());
System.out.println("Error Message: " + e.getMessage());
} catch (BceClientException e) {
System.out.println("Error Message: " + e.getMessage());
}
}
}).start();
}}获取所有已上传的分块信息
用户可以使用 listParts 方法获取某个上传事件中所有已上传的块。
基本流程
- 创建ListPartsRequest类的实例,传入
<BucketName>,<ObjectKey>,<UploadId>参数。 - 创建BOSClient类的实例,执行BOSClient.listParts( )方法。
- listParts()返回所有已上传part的信息。
示例代码
ListPartsRequest listPartsRequest = new ListPartsRequest(<BucketName>, <ObjectKey>, <UploadId>);
// 获取上传的所有Part信息
ListPartsResponse partListing = client.listParts(listPartsRequest);
// 遍历所有Part
for (PartSummary part : partListing.getParts()) {
System.out.println("PartNumber: " + part.getPartNumber() + " ETag: " + part.getETag());
}注意：
- 默认情况下，如果Bucket中的分块上传事件的数目大于1000，则只会返回1000个Object，并且返回结果中IsTruncated的值为True，同时返回NextPartNumberMarker作为下次读取的起点。
- 若想获取更多已上传的分块信息，可以使用PartNumberMarker参数分次读取。
完整示例
import android.app.Activity;
import android.os.Bundle;
import com.baidubce.BceClientException;
import com.baidubce.BceServiceException;
import com.baidubce.auth.DefaultBceCredentials;
import com.baidubce.demo.R;
import com.baidubce.services.bos.BosClient;
import com.baidubce.services.bos.BosClientConfiguration;
import com.baidubce.services.bos.model.ListPartsRequest;
import com.baidubce.services.bos.model.ListPartsResponse;
import com.baidubce.services.bos.model.PartSummary;
public class ExampleActivity extends Activity {
private String bucketName = <BucketName>;
private String objectKey = <ObjectKey>;
private String uploadId = <UploadId>;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
new Thread(new Runnable() {
@Override
public void run() {
try {
BosClientConfiguration config = new BosClientConfiguration();
config.setCredentials(new DefaultBceCredentials(<AccessKeyID>, <SecretAccessKey>));
config.setEndpoint(<EndPoint>);
BosClient client = new BosClient(config);
ListPartsRequest listPartsRequest = new ListPartsRequest(<BucketName>, <ObjectKey>, <UploadId>);
listPartsRequest.setMaxParts(100);
listPartsRequest.setPartNumberMarker(50);
// 获取上传的所有Part信息
ListPartsResponse partListing = client.listParts(listPartsRequest);
// 遍历所有Part
for (PartSummary part : partListing.getParts()) {
System.out.println("PartNumber: " + part.getPartNumber() + " ETag: " + part.getETag());
}
} catch (BceServiceException e) {
System.out.println("Error ErrorCode: " + e.getErrorCode());
System.out.println("Error RequestId: " + e.getRequestId());
System.out.println("Error StatusCode: " + e.getStatusCode());
System.out.println("Error ErrorType: " + e.getErrorType());
System.out.println("Error Message: " + e.getMessage());
} catch (BceClientException e) {
System.out.println("Error Message: " + e.getMessage());
}
}
}).start();
}}封装分块上传
在Android SDK中，Bos为用户提供了putSuperObjectFromFile接口，它对分块上传涉及到的initiateMultipartUpload、UploadPart、completeMultipartUpload三个方法进行封装，用户只需调用该接口即可完成分块上传，同时，支持进度同步回调。
-
简单示例:
File file = new File("/path/to/file.zip"); PutSuperObjectRequest request = new PutSuperObjectRequest(bucketName, objectKey, file); bosClient.putSuperObjectFromFile(request); -
示例：设置分块大小为2MB，线程数为4，并且每1024个byte同步进度回调
BosClientConfiguration config=new BosClientConfiguration(); config.setUploadSegmentPart(1024); File file = new File("/path/to/file.zip"); PutSuperObjectRequest request = new PutSuperObjectRequest(bucketName, objectKey, file, 1024 * 1024 * 2L, 4); request.setProgressCallback(new BosProgressCallback<PutSuperObjectRequest>() { @Override public void onProgress(PutSuperObjectRequest request, long currentSize, long totalSize) { Log.e(currentSize + "", totalSize + ""); } }); bosClient.putSuperObjectFromFile(request);
注意：
- 默认情况下，分块大小是5MB，线程数是5，进度回调周期是每2048个byte。
- 若一个大文件耗时很长，用户想结束分块上传，可调用PutSuperObjectRequest中的cancel()方法。