Policy enforcing S3 standard storage class

Question

Is there a way to define a S3 bucket policy to enforce standard storage class? I want to prevent users from creating objects with reduced redundancy storage class.

Answer 1

You can now use a condition in an S3 bucket policy to constrain the creation of S3 objects (using PutObject) to specific storage classes.

The current version of the AWS documentation has an example - Restrict object uploads to objects with a specific storage class.

Suppose Account A owns a bucket and the account administrator wants to restrict Dave, a user in Account A, to be able to only upload objects to the bucket that will be stored with the STANDARD_IA storage class. The Account A administrator can accomplish this by using the s3:x-amz-storage-class condition key as shown in the following example bucket policy.

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Sid": "statement1",
      "Effect": "Allow",
      "Principal": {
        "AWS": "arn:aws:iam::AccountA-ID:user/Dave"
      },
      "Action": "s3:PutObject",
      "Resource": [
        "arn:aws:s3:::examplebucket/*"
      ],
      "Condition": {
        "StringEquals": {
          "s3:x-amz-storage-class": [
            "STANDARD_IA"
          ]
        }
      }
    }
  ]
}

Your values for Principal and Resource would be specific to your users and S3 bucket(s). The Condition constraint would need to change to STANDARD.