How to use C# SDK V1 to set and get bucket ACLs (C# SDK V1) - Object Storage Service

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 from other Alibaba Cloud services in the same region as OSS, use an internal endpoint. For more information about OSS regions and endpoints, see Regions and endpoints.
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 Initialization.
To configure the ACL of a bucket, you must have the oss:PutBucketAcl permission. To query the ACL of a bucket, you must have the oss:GetBucketAcl permission. For more information, see Attach a custom policy to a RAM user.

Set 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 code shows how to set the ACL of a bucket:

using System;
using Aliyun.OSS;
using Aliyun.OSS.Common;

namespace Samples
{
    public class Program
    {
        public static void Main(string[] args)
        {
            // Specify the endpoint of the region where the bucket is located. For example, if the bucket is in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com.
            var 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.
            var accessKeyId = Environment.GetEnvironmentVariable("OSS_ACCESS_KEY_ID");
            var accessKeySecret = Environment.GetEnvironmentVariable("OSS_ACCESS_KEY_SECRET");
            // Specify the bucket name. Example: examplebucket.
            var bucketName = "examplebucket";
            // Specify the region where the bucket is located. For example, if the bucket is in the China (Hangzhou) region, set the region to cn-hangzhou.
            const string region = "cn-hangzhou";
            // Create a ClientConfiguration instance and modify the default parameters as needed.
            var conf = new ClientConfiguration();
            // Use Signature V4.
            conf.SignatureVersion = SignatureVersion.V4;

            // Create an OssClient instance.
            var client = new OssClient(endpoint, accessKeyId, accessKeySecret, conf);
            client.SetRegion(region);
            
            try
            {
                // Set the bucket ACL to public-read.
                client.SetBucketAcl(bucketName, CannedAccessControlList.PublicRead);
                Console.WriteLine("Set bucket ACL succeeded");
            }
            catch (Exception ex)
            {
                Console.WriteLine("Set bucket ACL failed. {0}", ex.Message);
            }
        }
    }
}

Obtain bucket access permissions

The following sample code provides an example on how to query the ACL of a bucket:

using System;
using Aliyun.OSS;
using Aliyun.OSS.Common;

namespace Samples
{
    public class Program
    {
        public static void Main(string[] args)
        {
            // Specify the endpoint of the region where the bucket is located. For example, if the bucket is in the China (Hangzhou) region, set the endpoint to https://oss-cn-hangzhou.aliyuncs.com.
            var 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.
            var accessKeyId = Environment.GetEnvironmentVariable("OSS_ACCESS_KEY_ID");
            var accessKeySecret = Environment.GetEnvironmentVariable("OSS_ACCESS_KEY_SECRET");
            // Specify the bucket name. Example: examplebucket.
            var bucketName = "examplebucket";
            // Specify the region where the bucket is located. For example, if the bucket is in the China (Hangzhou) region, set the region to cn-hangzhou.
            const string region = "cn-hangzhou";
            // Create a ClientConfiguration instance and modify the default parameters as needed.
            var conf = new ClientConfiguration();
            // Use Signature V4.
            conf.SignatureVersion = SignatureVersion.V4;

            // Create an OssClient instance.
            var client = new OssClient(endpoint, accessKeyId, accessKeySecret, conf);
            client.SetRegion(region);
            
            try
            {

                var acl = client.GetBucketAcl(bucketName);
                Console.WriteLine("Get bucket ACL success {0}", acl.ACL);
            }
            catch (Exception ex)
            {
                Console.WriteLine("Get bucket ACL failed. {0}", ex.Message);
            }
        }
    }
}

References

For the complete sample code that is used to set the ACL of a bucket, see the GitHub example.
For the complete sample code that is used to retrieve the ACL of a bucket, see the GitHub example.
For more information about the API operation that is used to set the ACL of a bucket, see PutBucketAcl.
For more information about the API operation that is used to retrieve the ACL of a bucket, see GetBucketAcl.