This is a note-to-self about Fn:Transform in AWS CloudFormation. When combined with the macro AWS::Include, as of today, the included template is limit to these functions:

  • Fn::Base64
  • Fn::GetAtt
  • Fn::GetAZs
  • Fn::ImportValue
  • Fn::Join
  • Fn::Split
  • Fn::FindInMap
  • Fn::Select
  • Ref
  • Fn::Equals
  • Fn::If
  • Fn::Not
  • Condition
  • Fn::And
  • Fn::Or
  • Fn::Contains
  • Fn::EachMemberEquals
  • Fn::EachMemberIn
  • Fn::ValueOf
  • Fn::ValueOfAll
  • Fn::RefAll
  • Fn::Sub
  • Fn::Cidr

By the way, isn’t it amazing that only Ref and Condition are available in short form? Where’s the consistency, AWS?