Constant aws_iam::constants::AWS_SOURCE_ARN

pub const AWS_SOURCE_ARN: &str

Use this key to compare the source of the request with the Amazon Resource Name (ARN) that you specify in the policy.

For example, when an Amazon S3 bucket update triggers an Amazon SNS topic post, the Amazon S3 service invokes the sns:Publish API operation. The bucket is considered the source of the SNS request and the value of the key is the bucket's ARN. This key does not work with the ARN of the principal making the request. Instead, use aws:PrincipalArn.