If the expiration is configured for the object (see PutBucketLifecycleConfiguration),
the response includes this header. It includes the expiry-date and rule-id
key-value pairs that provide information about object expiration. The value
of the rule-id is URL encoded.
If you specified server-side encryption either with an AWS KMS customer
master key (CMK) or Amazon S3-managed encryption key in your PUT request,
the response includes this header. It confirms the encryption algorithm that
Amazon S3 used to encrypt the object.
If server-side encryption with a customer-provided encryption key was
requested, the response will include this header confirming the encryption
algorithm used.
If server-side encryption with a customer-provided encryption key was
requested, the response will include this header to provide round-trip
message integrity verification of the customer-provided encryption key.
If present, specifies the AWS KMS Encryption Context to use for object
encryption. The value of this header is a base64-encoded UTF-8 string
holding JSON with the encryption context key-value pairs.
If x-amz-server-side-encryption is present and has the value of
aws:kms, this header specifies the ID of the AWS Key Management
Service (AWS KMS) symmetric customer managed customer master key (CMK) that
was used for the object.