A bucket is a container for objects stored in Object Storage Service (OSS). All objects in OSS are stored in buckets. This topic describes how to configure and query the access control list (ACL) of a bucket.
Usage notes
In this topic, the public endpoint of the China (Hangzhou) region is used. If you want to access OSS by using other Alibaba Cloud services in the same region as OSS, use an internal endpoint. For more information about the regions and endpoints supported by OSS, see Regions and endpoints.
In this topic, access credentials are obtained from environment variables. For more information about how to configure access credentials, see Configure access credentials.
In this topic, an OSSClient instance is created by using an OSS endpoint. If you want to create an OSSClient instance by using custom domain names or Security Token Service (STS), see Create an OSSClient instance.
To configure the ACL of a bucket, you must have the
oss:PutBucketAcl
permission. To query the ACL of a bucket, you must have theoss:GetBucketAcl
permission. For more information, see Common examples of RAM policies.
Configure the ACL of a bucket
The following table describes the bucket ACLs.
ACL | Description | Method |
Private | Only the bucket owner and authorized users have read and write permissions on objects in the bucket. Other users cannot access objects in the bucket. | CannedAccessControlList.Private |
Public-read | Only the bucket owner and authorized users have read and write permissions on objects in the bucket. Other users have only read permissions on objects in the bucket. Exercise caution when you set the bucket ACL to this value. | CannedAccessControlList.PublicRead |
Public-read-write | All users have read and write permissions on the objects in the bucket. Exercise caution when you set the bucket ACL to this value. | CannedAccessControlList.PublicReadWrite |
The following sample code provides an example on how to configure the ACL of a bucket:
import com.aliyun.oss.ClientException;
import com.aliyun.oss.OSS;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.OSSClientBuilder;
import com.aliyun.oss.OSSException;
import com.aliyun.oss.model.CannedAccessControlList;
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";
// Create an OSSClient instance.
OSS ossClient = new OSSClientBuilder().build(endpoint, credentialsProvider);
try {
// Specify the ACL of the bucket. In this example, the ACL of the examplebucket bucket is set to private.
ossClient.setBucketAcl(bucketName, CannedAccessControlList.Private);
} 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();
}
}
}
}
Query the ACL of a bucket
The following sample code provides an example on how to query the ACL of a bucket:
import com.aliyun.oss.ClientException;
import com.aliyun.oss.OSS;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.OSSClientBuilder;
import com.aliyun.oss.OSSException;
import com.aliyun.oss.model.AccessControlList;
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";
// Create an OSSClient instance.
OSS ossClient = new OSSClientBuilder().build(endpoint, credentialsProvider);
try {
// Query the ACL of the bucket.
AccessControlList acl = ossClient.getBucketAcl(bucketName);
System.out.println(acl.toString());
} 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();
}
}
}
}
References
For the complete sample code for managing the ACL of a bucket, visit GitHub.
For more information about the API operation for configuring the ACL of a bucket, see PutBucketAcl.
For more information about the API operation for querying the ACL of a bucket, see GetBucketAcl.