Hello all!
Welcome to the next issue of the Tidy Cloud AWS newsletter! In this issue, I will cover a bit on fixing shortcomings in CloudFormation, at least for some specific use cases. Enjoy!
CloudFormation custom resource challenges
CloudFormation has had custom resources and custom resource types for a while now. There were examples of custom resources in the past as early as 2014; custom resource types arrived a few years later.. The features have not been adopted widely, even with vendors creating custom resources. AWS has difficulty with consistent coverage across its Console, APIs, CLI, and CloudFormation. Custom resources handling has still been too much of a hurdle to be widely adopted to address these shortcomings.
AWS CDK to help
AWS CDK (Cloud Development Kit) is a successful and convenient way to use custom resources with CloudFormation. AWS CDK has custom resources to help with CloudFormation rough edges for various services.
Mostly, you only see that there are custom resources in action when your AWS CDK deployments include more AWS Lambda functions than you have defined yourself. AWS CDK also includes convenience features to make your own custom resources much simpler to define, at least for some use cases.
Look at my article on overcoming CloudFormation shortcomings with AWS CDK, if you are interested in a concrete example.
From a convenience point of view, it approaches Pulumi dynamic providers, although the underlying implementation is quite different.
You can find the contents of this bulletin and older ones, and more at Cloudgnosis.org. You will also find other useful articles around AWS automation and infrastructure-as-software.
Until next time,
/Erik