The google and google-beta split requires users to explicitly set the version of the Google provider for Terraform that they are using; see the Google Provider Versions page for more details.
This has complicated module creation as the schema between google and google-beta often differs; specifying a Beta feature with the google provider will give an error. This example module demonstrates how to create a “versioned” module that detects the necessary version for a resource based on the fields specified.
This example only solves the simple case of a single beta field in a single resource, but should give module developers the right ideas on how to develop more complex modules intermixing google and google-beta.