Este tópico descreve como fazer upload de objetos para um bucket com versionamento habilitado no Object Storage Service (OSS).
Observações de uso
Este tópico utiliza o endpoint público da região China (Hangzhou). Para acessar o OSS a partir de outros serviços da Alibaba Cloud na mesma região, use um endpoint interno. Para obter detalhes sobre as regiões e endpoints compatíveis, consulte Regiões e endpoints.
Neste exemplo, as credenciais de acesso são obtidas de variáveis de ambiente. Para mais informações, consulte Configurar credenciais de acesso.
Este tópico demonstra a criação de uma instância OSSClient com um endpoint do OSS. Para configurações alternativas, como uso de domínio personalizado ou autenticação com credenciais do Security Token Service (STS), consulte Configuração do cliente.
Para fazer upload de um objeto, você precisa da permissão
oss:PutObject. Para mais informações, consulte Conceder uma política personalizada.
Upload simples
Ao fazer upload de um objeto para um bucket com versionamento habilitado, o OSS gera um ID de versão exclusivo para o objeto e o inclui no cabeçalho de resposta x-oss-version-id. Se você fizer upload em um bucket com versionamento suspenso, o ID de versão gerado será null. Caso faça upload de um objeto com o mesmo nome de um objeto existente em um bucket com versionamento suspenso, o objeto existente será sobrescrito. Assim, cada objeto terá apenas uma única versão com ID null.
O código de exemplo a seguir mostra como fazer upload de um objeto para um bucket com versionamento habilitado usando upload simples:
import com.aliyun.oss.*;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.model.*;
import java.io.ByteArrayInputStream;
public class Demo {
public static void main(String[] args) throws Exception {
// In this example, the endpoint of the China (Hangzhou) region is used. Specify your actual endpoint.
String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
// Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured.
EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
// Specify the name of the bucket. Example: examplebucket.
String bucketName = "examplebucket";
// Specify the full path of the object. Do not include the bucket name in the full path.
String objectName = "exampledir/object";
// Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to cn-hangzhou.
String region = "cn-hangzhou";
// Create an OSSClient instance.
// Call the shutdown method to release resources when the OSSClient is no longer in use.
ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);
OSS ossClient = OSSClientBuilder.create()
.endpoint(endpoint)
.credentialsProvider(credentialsProvider)
.clientConfiguration(clientBuilderConfiguration)
.region(region)
.build();
try {
// In this example, a string is uploaded as an object.
String content = "Hello OSS";
PutObjectResult result = ossClient.putObject(bucketName, objectName, new ByteArrayInputStream(content.getBytes()));
// Display the version ID of the object.
System.out.println("result.versionid: " + result.getVersionId());
} catch (OSSException oe) {
System.out.println("Caught an OSSException, which means your request made it to OSS, "
+ "but was rejected with an error response for some reason.");
System.out.println("Error Message:" + oe.getErrorMessage());
System.out.println("Error Code:" + oe.getErrorCode());
System.out.println("Request ID:" + oe.getRequestId());
System.out.println("Host ID:" + oe.getHostId());
} catch (ClientException ce) {
System.out.println("Caught an ClientException, which means the client encountered "
+ "a serious internal problem while trying to communicate with OSS, "
+ "such as not being able to access the network.");
System.out.println("Error Message:" + ce.getMessage());
} finally {
if (ossClient != null) {
ossClient.shutdown();
}
}
}
}Upload por acréscimo
Em um bucket com versionamento habilitado, a operação AppendObject só pode ser executada na versão atual de um objeto anexável.
Nota
Ao executar a operação AppendObject na versão atual de um objeto anexável, o OSS não gera uma versão anterior para o objeto.
Quando você executa a operação PutObject ou DeleteObject na versão atual de um objeto anexável, o OSS salva o objeto anexável como uma versão anterior, que não pode mais receber acréscimos.
Não é possível executar a operação AppendObject na versão atual de um objeto não anexável, como um objeto normal ou um marcador de exclusão.
O código de exemplo a seguir mostra como fazer upload de um objeto usando upload por acréscimo:
import com.aliyun.oss.*;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.model.*;
import java.io.ByteArrayInputStream;
public class Demo {
public static void main(String[] args) throws Exception {
// In this example, the endpoint of the China (Hangzhou) region is used. Specify your actual endpoint.
String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
// Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured.
EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
// Specify the name of the bucket. Example: examplebucket.
String bucketName = "examplebucket";
// Specify the full path of the object. Do not include the bucket name in the full path.
String objectName = "exampledir/object";
String content1 = "Hello OSS A \n";
String content2 = "Hello OSS B \n";
String content3 = "Hello OSS C \n";
// Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to cn-hangzhou.
String region = "cn-hangzhou";
// Create an OSSClient instance.
// Call the shutdown method to release resources when the OSSClient is no longer in use.
ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);
OSS ossClient = OSSClientBuilder.create()
.endpoint(endpoint)
.credentialsProvider(credentialsProvider)
.clientConfiguration(clientBuilderConfiguration)
.region(region)
.build();
try {
ObjectMetadata meta = new ObjectMetadata();
// Specify the type of content to upload.
meta.setContentType("text/plain");
// Configure multiple parameters by using AppendObjectRequest.
AppendObjectRequest appendObjectRequest = new AppendObjectRequest(bucketName, objectName, new ByteArrayInputStream(content1.getBytes()),meta);
// Configure a single parameter by using AppendObjectRequest.
// Specify the name of the bucket.
//appendObjectRequest.setBucketName("<yourBucketName>");
// Specify the name of the object.
//appendObjectRequest.setKey("<yourObjectName>");
// Configure the type of the content that you want to append. Two content types are available: InputStream and File. The following code provides an example on how to specify the content of the InputStream type.
//appendObjectRequest.setInputStream(new ByteArrayInputStream(content1.getBytes()));
// Configure the type of the content that you want to append. Two content types are available: InputStream and File. The following code provides an example on how to specify the content of the File type.
//appendObjectRequest.setFile(new File("<yourLocalFile>"));
// Specify the metadata of the object. You can specify the metadata only when you perform the first append operation on the object.
//appendObjectRequest.setMetadata(meta);
// Perform the first append operation.
// Specify the position from which the append operation starts.
appendObjectRequest.setPosition(0L);
AppendObjectResult appendObjectResult = ossClient.appendObject(appendObjectRequest);
// Calculate the 64-bit CRC value of the object. The value is calculated based on the ECMA-182 standard.
System.out.println(appendObjectResult.getObjectCRC());
// Perform the second append operation.
// nextPosition indicates the position from which the next append operation starts. This is the current length of the object.
appendObjectRequest.setPosition(appendObjectResult.getNextPosition());
appendObjectRequest.setInputStream(new ByteArrayInputStream(content2.getBytes()));
appendObjectResult = ossClient.appendObject(appendObjectRequest);
// Perform the third append operation.
appendObjectRequest.setPosition(appendObjectResult.getNextPosition());
appendObjectRequest.setInputStream(new ByteArrayInputStream(content3.getBytes()));
appendObjectResult = ossClient.appendObject(appendObjectRequest);
} catch (OSSException oe) {
System.out.println("Caught an OSSException, which means your request made it to OSS, "
+ "but was rejected with an error response for some reason.");
System.out.println("Error Message:" + oe.getErrorMessage());
System.out.println("Error Code:" + oe.getErrorCode());
System.out.println("Request ID:" + oe.getRequestId());
System.out.println("Host ID:" + oe.getHostId());
} catch (ClientException ce) {
System.out.println("Caught an ClientException, which means the client encountered "
+ "a serious internal problem while trying to communicate with OSS, "
+ "such as not being able to access the network.");
System.out.println("Error Message:" + ce.getMessage());
} finally {
if (ossClient != null) {
ossClient.shutdown();
}
}
}
}Upload multipart
Ao chamar a operação CompleteMultipartUpload para concluir a tarefa de upload multipart de um objeto em um bucket com versionamento habilitado, o OSS gera um ID de versão exclusivo para o objeto e retorna esse ID como valor do cabeçalho x-oss-version-id na resposta.
O código a seguir exemplifica como fazer upload de um objeto para um bucket com versionamento habilitado usando upload multipart:
import com.aliyun.oss.*;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.model.*;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;
public class Demo {
public static void main(String[] args) throws Exception {
// In this example, the endpoint of the China (Hangzhou) region is used. Specify your actual endpoint.
String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
// Obtain access credentials from environment variables. Before you run the sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are configured.
EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
// Specify the name of the bucket. Example: examplebucket.
String bucketName = "examplebucket";
// Specify the full path of the object. Do not include the bucket name in the full path.
String objectName = "exampledir/object";
String localFile = "D://example.txt";
// Specify the region in which the bucket is located. For example, if the bucket is located in the China (Hangzhou) region, set the region to cn-hangzhou.
String region = "cn-hangzhou";
// Create an OSSClient instance.
// Call the shutdown method to release resources when the OSSClient is no longer in use.
ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);
OSS ossClient = OSSClientBuilder.create()
.endpoint(endpoint)
.credentialsProvider(credentialsProvider)
.clientConfiguration(clientBuilderConfiguration)
.region(region)
.build();
try {
/* Step 1: Initiate a multipart upload event.
*/
InitiateMultipartUploadRequest request = new InitiateMultipartUploadRequest(bucketName, objectName);
InitiateMultipartUploadResult upresult = ossClient.initiateMultipartUpload(request);
// Obtain an upload ID. The upload ID uniquely identifies the multipart upload task. You can use the upload ID to initiate related requests such as canceling and querying the multipart upload task.
String uploadId = upresult.getUploadId();
/* Step 2: Upload parts.
*/
// partETags is a set of PartETags. A PartETag consists of the part number and ETag of an uploaded part
List<PartETag> partETags = new ArrayList<PartETag>();
// Calculate the total number of parts.
final long partSize = 1 * 1024 * 1024L; // 1MB
final File sampleFile = new File(localFile);
long fileLength = sampleFile.length();
int partCount = (int) (fileLength / partSize);
if (fileLength % partSize != 0) {
partCount++;
}
// Upload all parts.
for (int i = 0; i < partCount; i++) {
long startPos = i * partSize;
long curPartSize = (i + 1 == partCount) ? (fileLength - startPos) : partSize;
InputStream instream = new FileInputStream(sampleFile);
// Skip parts that have been uploaded.
instream.skip(startPos);
UploadPartRequest uploadPartRequest = new UploadPartRequest();
uploadPartRequest.setBucketName(bucketName);
uploadPartRequest.setKey(objectName);
uploadPartRequest.setUploadId(uploadId);
uploadPartRequest.setInputStream(instream);
// Specify the size of each part. Each part except the last part must be equal to or greater than 100 KB in size.
uploadPartRequest.setPartSize(curPartSize);
// Configure part numbers. Each part is configured with a part number. The value ranges from 1 to 10000. If you configure a number beyond the range, OSS returns an InvalidArgument error code.
uploadPartRequest.setPartNumber( i + 1);
// Parts are not necessarily uploaded in order and can be uploaded from different OSS clients. OSS sorts the parts based on the part numbers and combines the parts into a complete object.
UploadPartResult uploadPartResult = ossClient.uploadPart(uploadPartRequest);
// After you upload a part, OSS returns a result that contains a PartETag. The PartETag is stored in partETags.
partETags.add(uploadPartResult.getPartETag());
}
/* Step 3: Complete multipart upload.
*/
// You must provide all valid PartETags when you perform this operation. OSS verifies the validity of all parts one by one after it receives the PartETags. After all parts are verified, OSS combines these parts into a complete object.
CompleteMultipartUploadRequest completeMultipartUploadRequest =
new CompleteMultipartUploadRequest(bucketName, objectName, uploadId, partETags);
CompleteMultipartUploadResult completeMultipartUploadResult = ossClient.completeMultipartUpload(completeMultipartUploadRequest);
// Query the version ID of the uploaded object.
System.out.println("restore object versionid: " + completeMultipartUploadResult.getVersionId());
} catch (OSSException oe) {
System.out.println("Caught an OSSException, which means your request made it to OSS, "
+ "but was rejected with an error response for some reason.");
System.out.println("Error Message:" + oe.getErrorMessage());
System.out.println("Error Code:" + oe.getErrorCode());
System.out.println("Request ID:" + oe.getRequestId());
System.out.println("Host ID:" + oe.getHostId());
} catch (ClientException ce) {
System.out.println("Caught an ClientException, which means the client encountered "
+ "a serious internal problem while trying to communicate with OSS, "
+ "such as not being able to access the network.");
System.out.println("Error Message:" + ce.getMessage());
} finally {
if (ossClient != null) {
ossClient.shutdown();
}
}
}
}Referências
Para mais informações sobre a operação de API de upload simples, consulte PutObject.
Para detalhes sobre a operação de API de upload por acréscimo, consulte AppendObject.
Para saber mais sobre a operação de API de conclusão de upload multipart, consulte CompleteMultipartUpload.