Metadata Attribute

The Metadata attribute enables you to associate structured data with a resource. By adding a Metadata attribute to a resource, you can add data in JSON format to the resource declaration. In addition, you can use intrinsic functions (such as GetAtt and Ref), parameters, and pseudo parameters within the Metadata attribute to add those interpreted values.

You can retrieve this data using the cfn-describe-stack-resource command or the DescribeStackResource action.

{
   "AWSTemplateFormatVersion" : "2010-09-09",
   "Resources" : {
      "MyS3Bucket" : {
         "Type" : "AWS::S3::Bucket",
         "Metadata" : { "Object1" : "Location1",  "Object2" : "Location2" }
      }
   }
}