A Simple Example of “Lambda-backed Custom Resource” in AWS CloudFormation
The minimal working snippets of the custom resource function.
How to Use the CloudFormation Sub Function
Since I started using AWS CloudFormation 4 years ago, I have seen many people using the Fn::Join command to merge information such as static text and variables in their CloudFormation templates. While this works, it can get messy and difficult to understand when things get complicated. Fn::Sub helps simplify our template definitions.