How do you specify a tag of v1.0.0 when referencing a Git module?

To specify a tag of v1.0.0 when referencing a Git module in Terraform, using the argument ref=v1.0.0 is the correct approach. The ref argument allows you to define a specific version of the module you wish to use, whether it be a branch, tag, or commit hash. By setting ref to v1.0.0, Terraform will pull the module code associated with that specific tag from the Git repository.

This method ensures that your infrastructure configuration is consistent and reproducible by locking it to a known, stable version of the module, rather than relying on the latest commit from the repository, which may lead to unexpected changes and behaviors in your deployments.

Regarding the other options, appending IT to the URL, adding v1.0.0 after the repository name, or including version in the configuration file may not follow the standard syntax and semantics that Terraform expects when working with Git module sources. Thus, they would not effectively achieve the goal of accurately pinning to that specific version.