Is it possible to use existing terraform modules with higher level programming languages running the CDK?
As an example we have our own internal re-usable modules, but have a particular project that is running on an automated schedule. The schedule is managed by a C# app. We do not want to have to re-write all the modules to use them in this app and am hoping there is a way to use the CDK to read existing *.tf & *.tfvar files.
You can use existing Terraform modules written in HCL in CDK for Terraform projects. You don’t have to rewrite them
But as you mentioned a C# app running on a schedule: While a CDKTF project is written in C#, invoking it (i.e. applying changes to infrastructure) requires the CDKTF CLI and currently there is no API to programmatically plan/apply changes. Here’s the open issue tracking this: API to interact with terraform cli · Issue #237 · hashicorp/terraform-cdk · GitHub